Transcript for:
Notes on Webinar: Production Logging Tools

good afternoon everyone and Welcome to our webinar thank you for joining us this afternoon my name is Jama Tarn dzic I'm studying for a master's degree in petroleum engineering at University of Houston and I will be your moderator this afternoon today we're pleased to welcome engineer Maria Laticia Vasquez a very special guest from Mexico engineer Maria has a BSC mechanical engineering and has been working in sjer for 19 years within the W line organization Maria has per performed three different major roles in the Wireline uh case toll business in Egypt om man Scotland and Sudan a field engineer casole logging instructor and domain Champion for well Integrity production logging and perforation and today she will be sharing with us her expert opinion on production logging tools please feel free to send your questions in the chat box and we'll answer as many questions as possible with that I ask ask you to give your full attention to engineer Maria and help me in welcoming her please welcome engineer Maria hi engineer Maria thanks for joining us today thank you very much for the great invitation so my name is Maria Vasquez and today we are going to talk about production logging and basically production logging something that we have to consider is that it is a wellb measurement in general and the most important ER part about production logging is to understand how much is my well delivering from where is coming the oil from where is coming the water from where is coming the gas into the well so as you can see over here in the picture that that you have in the slide H the first thing that we have is a here we you you can see is two wells in the well in the left we see that there is Water Production from the Zone number three from the most bottom perforation P3 and then we have that zone number two P2 is taking some of this water and this can happen because the pressure in the zone number three is higher than the pressure in the zone number two and then we see that some of the water is being produced and Zone number one is basically producing only hydrocarbon so this is one of the type of problems that we would like to identify with production logging in the well in the right we can see that there is a poor cement H behind the casing so we can see that the water is going through the channeling through the cement and even though our h z is just hydrocarbon beaing we have actually water entry due to the poor cement in behind the casing so this is what we call Water Production through channeling and of course that is is going to affect the performance of the well so basically this is just a brief introduction but why is production logging perform so again as I mentioned before we need to know how much of what is coming from where so basically we are going to measure the parameters of the well Zone by Zone to be able to understand how the fluids are moving in the wello we can also see some to some extent movement of fluids behind the casing but our main interest is going to be the wello so over here in this picture that I have in this slide we can see the Schlumberger truck or any truck from any service company and we see over here the rig up on the on the on the on the on the wellhe head yeah in this case this the Christmas tree most of the production loing surveys are done rigless meaning that the rig is not in place yeah we can we also do surveys with the rig in place but most of this kind of work is done rigless and already with the completion in place so you will have over here the Christmas tree yeah and then you lower your H Production Tool with the warline cable and you can actually ER see over here every Zone how much is every Zone producing yeah you so basically this is the idea to understand how much h of what is coming from where and we can see over here just a small example of the measurements that are done but we will describe one by one all these measurements so talking about problems that production log in can identify so the main core of production loing will be number one evaluation so we want to see the production profile distribution and the zal productivity this could be even a baseline log once you uh have already your completion in place and you already or even along with the testing you can actually do production logging and understand the status of the Well when the well is actually new yeah and understand which zones are producing which type of fluids are entering from every zone so this will be for evaluation Next Step will be monitoring so with the time also the production profile is going to change many times we do production logging several times through the history of the well to understand how the production profile is changing and also to understand if there is any remedial that we should do to be able to stop producing un unwanted fluids this could be water or this could be gas so we can identify water break through gas break through in case we don't want to produce gas for example but we want only to produce oil and also Al for diagnosis so basically what is the zone of a high G or a high water cut and also to detect if we have presence of cross flow H we can see over here in the in the picture that is on my down right side you can see the example for example of a thief zone so Thief Zone again is whenever the pressure of the of of one of the zones is higher than the pressure of the other Zone and then the fluid is being taken by the Press by The Zone with low pressure so this also what we call cross flow also whenever we want to do any production enhancement so H to be able to understand ER so some data to be able to enhance to plan for our workover to to be able to plan for any change in completion as well because sometimes we have leaks so for example in the in in the top left side we can see the example of a a packer leak and we can see also a leak in the tubing so these are things that we would like to understand to see what will be the remedial to be applied for example we might need to retrieve the completion and be able to change this tubing that is having leak that is having already holes by a new completion yeah and also the Packers so so it can also help us to understand the status of the well and plan for workover operations so now we are going to see which are the sensors that are available typically in a production logging string okay so which are our needs in production logging our needs are to understand quantity of oil quantity of gas and quantity of water and we know that the flow rate is equal to Velocity times area and the measurements that we would like to do are the velocity of fluid how are we going to measure the velocity of the fluid we will do that with what we call a spinner so you also will hear the name as flow meter and another way of understanding the velocity of fluid can be through a nuclear measurement called water flow log H we need to know the diameter of the casing because at the end of the day we say that flow rate is equal to Velocity times area so the diameter of the casing we can know it by a caliper so we can have you know s production loging string a caliper hold up we can measure it with different type of sensors one of them will be the density sensor we have in a schlomer also what we call the electrical probe and we have also a gas hold up sensor called the optical Pro if we need to measure temperature we have an RTD and if we want to measure pressure we can do it with a pressure gauge some Sapphire gauge or quartz gauge so over here I have a picture of the production logging sensors and we can see over here the basic sensor that contains typically temperature pressure gamma ray and CCL for correlation and we can see over here the spinner flow meter this is what we call a full board spinner yeah so the spinner is basically enclosed in a cage in this case this cage is also going to act as a caliper and we can see over here the electrical probe the electrical probe will help us to understand the water hold up presence we can see the optical probe that will help us to understand the gas hold up presence we have the gradi manometer tool that will measure the wellber fluid density and we have as well nuclear tools that could help help us to understand saturation and also water movement H what we call the water flow log measurement yeah now the basic the very basic PLT string will be the pressure temperature gamma a spinner and caliper this will be our very basic PLT string now production logging is not done in the same way any other logging is performed normally whenever you log you go down to your target logging bottom log interval and then you go up by recording whatever you need to record okay in production logging the program is a little bit different so basically the production loging program typically there might be variations to this but typically is divided in shoting condition and flowing condition so in shoting condition the well is static and what we are going to do is that we are going to to perform several passes at different speeds and we have to maintain through the logging interval the speed constant this is to be able to perform what we call a spinner calibration now when I perform when I the spinner whenever it provides the measurement the spinner is going to provide the measurement in RPS revolutions per second the spinner rotates but in reality I do not need revolutions per second I need a linear velocity so the spinner calibration will help me to transl that rotational velocity into a linear velocity and at the end of the day what we are going to obtain or what we need to obtain is the velocity of the flow then H the shoting condition also help us to determine fluid levels so for example where are the segregation between water oil gas in the wo and also is going to be the main condition in which we can detect cross flow so for example we can detect if a pressure so is what I mentioned before a zone that is having a higher pressure that is feeding into a Zone with lower pressure also that is going to be mainly observed in the shoting condition now once we open the well to production we need to wait for the for the flow to be a stable flow and typically we understand that by looking at our pressure sensor also the spinner temperature density we see that our pressure is constant and then we can start to perform passes op down passes at different speeds across the loging interval and in this case also this the purpose of this passes is to identify the flow profile to identify the fluid entries and again also to help us with the spinner calibration and typically we also do stations and these stations are very important because they will confirm Whenever there is a flow coming from a particular Zone it is going to be a confirmation yeah we can see over here the the well how it's producing yeah so now for production Lo interpretation what are the facts so what are the things that we can determine and interpret if I have a single phase scenario I can determine the downhall profile and H the interpretation is be really straightforward I just need my spinner I just need pressure temperature gamare and CCL for that if I have a multi flow meaning I have a oil produced with water or I have gas produced with oil or I have gas water and oil the three of them of them produce at the same time then we need also H this interpretation we will need to know the hold basically so how much space is going to be occupied by every phase in the wello and we also need to determine something called slipage velocity so all this will complicate the way the spinner is going to rotate so it's very important that we have hold of sensors in this case and our interpretation model will have what we call slipage correlations that will help us to be able to reach a conclusion so the the the hold up is basically a major importance in the multiphase flow production loging interpretation now something that is very important and we insist the a lot to our customers whenever we are going to plan for a production loging job is that they provide us as accurate as possible PBT data and the reason is because any some failures to provide an accurate P data can induce errors in the calculations that are going to be done by the production logging and in the interpretation now something that can reduce the error of inaccuracy on the PBT data is to have hold up sensors that can directly measure the hold up of water and the hold up of gas but if we are going to work traditionally with a density measurement like the gradi manometer tool it is very important that we know accurately the downhall density of every phase it is something important for the proper and accurate interpretation of the production logging H ER log okay so for example when I have my electrical probe or my Optical probe that that that identifies the water hold up and the gas hold up then I can eliminate many of the errors that are induced by the PBT H data in the interpretation now we are going to talk a little bit basic very basic understanding on Flow regimes so flow regimes typically we will have what we call the laminar flow and we will have the turbulent flow and how are we going to Define laminar flow to turbulent from turbulent flow in this case for example in the laminar flow something that we have to understand is that the spinner is actually centralized in the casing yeah so the spinner is centralizing the casing so if I am in the presence of a laminar flow I will have the spinner reading maximum velocity and in laminar flow velocity average which is what I actually would like to measure is equal to the velocity maximum divided by two okay this is in the case of linar flow but in reality in oil field we don't really deal with laminar flow we deal with turbulent and transition flow we we don't deal really with the laminar flow so in the case of turbulent flow the velocity average okay is the the relationship between the velocity maximum and the velocity average is going to be given by something called velocity profile correction factor now how we know that the flow is going to be laminar or turbulent this is based on something called rains number okay whenever rains number is less than 2,000 then this considered a laminar flow whenever the rain number is more than 2,000 we consider this as a turbulent flow and again polyphasic flow is always turbulent or transition so H the inputs to a to rinal number things that we have to consider and that are inputs to rain's number is going to be number one the diameter of the pipe the fluid velocity the fluid density and the fluid viscosity yeah so our Prof velocity profile correction factor at the end is dependent on the rainor number and the input of these values is actually need to be correct now H we are typically whenever I give this presentation we do an spinner exercise but in this case we don't really have time for the spinner exercise but we are going to do I will explain to you now about the spinner sensor itself so as you can see over here the spinner is centralized okay we have basically the caliper is going to help us to measure the area or or basically measure the diameter and then we will be able to calculate the area and then we have the spinner that the end of the day our our output that we require is the velocity of the mixture but as I as I said our final answer that we want is the flow rate and for that we need the velocity of the mixture in a linear velocity not in a rotational velocity and the spinner as you can see is always to be centralized inside the casing now something here that we have whenever we H look at the spinner response we are going to be in a in the presence of two factors two variables number one the velocity of the flow and number two the velocity of the cable because the passes that we are going to be doing up and down at different cable speeds we are going to basically be moving the tool we are going to be moving the cable but at the same time we have the velocity of the flow either if it is injection or if it is production so basically at the end what we want to understand is the relative fluid velocity to to to to Tool velocity so we can see over here how whenever I take all my passes all my up and down passes what we do is that we merge these passes into a produ into a format Yeah so basically into a picture in this case so this is the log this a representation of the production log the spinner in this case so you can see in the left side the different cable velocities and something very important is that we should always keep the cable velocity constant then H this shaded area is the perforation and then on the left side you will see the spinner response in RPS Revolution per second So Below the perforation nothing is moving I have no flow coming from below the perforation unless I have old perforations that have been isolated by a plug for example and are leaking and the plug is leaking in this case let's say that no there is no leak of any kind and I have just this perforation Zone and there is no flow coming from the bottom so the first Zone highlighted in purple in the bottom is what I will call zero flow region no flow is H inter making the spinner rotate in this case inste of low region all the rotation of the spinner is dependent on the cable velocity then I see that over here my spinner is increasing in magnitude this is because now I have production entering from the perforation I have flow entering from the perforation my perforation is producing so in this case I have the cable velocity plus the velocity of the flow that is entering inside the WBO through the perforation and then at the top region I will also select a Zone in in purple as well and this will be my flow region okay so so like this we can understand H basically what is a zero flow region and what is a flowing region okay and again cable speed is very important to maintain con constant whenever I merge H my passes my spinner response has to be repeating so for examp I I should not have a different shape from one pass to another pass this is part of the quality control that we need to do to the spinner passes all the shape of our spinner ER passes have to be the same depend independent on the velocity at which we are acquiring them now a convention in production logging whenever you are either a logging engineer on our interpreter so for us positive cable velocity is going to be given even whenever you are going down you are making a down pass so how we actually consider it or memorize it is we consider that whenever you are going down your depth is increasing yeah so then the velocity of the spinner the rotational velocity of the spinner we consider it positive let's say that the well is in a static condition there is no production there is no fluid movement but I am just moving the cable and I am going down when I am going down with the cable in static condition with a well in a static condition only moving the cable my spinner is going to be rotating with a positive sign now let's say I'm going up also the well is completely static condition I am not I am not having any production or injection no Dynamics I am just moving the cable up my spinner in this case is going to be rotating negative so you will have that the spinner the sensor in the spinner can tell us okay a spinner is rotating positive or spinner is rotating negative now consider that I am having a perforation that is producing and I am not moving the cable at all any fluid that is coming from bottom to top in this case production for example is going to make the spinner rotate positive and whenever I have any fluid coming from top to bottom for example in the case of injectors wells in the case of injection the spinner is going to be rotating negative so for example let's say I have a producer well and I am moving my cable down whenever I am below the perforation the spinner is going to be rotating positive but whenever I am in front of the producing Zone my spinner is going to rotate now more positive okay because production makes the spinner rotate positive and moving the cable downwards make the spinner to rotate positive okay now whenever we are going to do the spinner calibration basically those passes that you that you saw we are going to plot them together okay we are going to have here the tool velocity and we are going to have here the spinner RPS so these points these green points that you see in this plot are basically the tool velocity let's say I am moving my cable at 30 feet per minute what is the RPS that I was reading when moving the cable at 30 ft per minute and I will actually plot my point then I was moving the cable at a let's consider this that this is the zero flow Zone that we saw in the previous slide yeah I am moving my cable at H 60 feet per minute so what is the RPS that my spinner is reading at 60 feet per minute and so on with all the different cable velocities and then we are going to trace or the software actually or you can do it by hand we will Trace here A A best feet calibration line now in reality okay if we were having an instrument that doesn't suffer from friction okay our our line should start from zero but in reality the spinner is a mechanical instrument that will suffer from friction the spinner will not start to rotate immediately it will rotate with certain when exposed to certain flow certain amount of of of of flow or velocity of the cable another thing that will make an impact on the spinner calibration the fluid is viscous so the the more viscosity of the fluid also the more lag for the spinner to start rotating so this distance from the time in which I start moving to or or the fluid start passing through the spinner until the spinner will start is Rota is what we call threshold velocity and whenever we have wells especially Wells that are not producing with very high rates this threshold velocity is going to be very important during the interpretation and during the spinner calibration but if we have a well that is producing millions of a standard cubic feet of gas for example or or very high amount of barrels per day then the threshold velocity becomes really a we don't really consider it that much in the interpretation yeah so you can see over here again the same example that I show you before you have your zero flow region so the points that you see in the previous slide I could take them from this zero flow region then if I want to trace my flowing line I will take the points from this flowing region yeah so now you see this points in blue I took them from my readings in this flowing region yeah so I said okay my spinner rotating at 30 ft per minute how much how many RPS I am seeing in my flowing region yeah now to select the regions or what we call also calibration zones we have to make sure that the spinner is constant yeah I cannot select a a a flowing a calibration Zone when the spinner is changing very important to select the calibration zones where the spinner is already constant so then what I do is that I will take my H points and I will Trace them yeah I will Trace over here okay this is 30 feet per minute how much is the spinner rotating UH 60 feet per minute this is the RPS with 60 fet per minute and this is the RPS with 90 ft per minute and so on now the distance between my zero flow line and my flowing line is basically the fluid velocity this is the velocity of the fluid in the wello okay and as you can see the velocity of the threshold velocity is important and you can this is important for the calibration when you do it by hand or you do it by software but at the end of the day graphically the distance between the Z flow line that I trace with the from the log compared to the flowing line that they trace also from the log this distance is the fluid velocity okay so we can see over here this is another way of putting it velocity of the mixture is equal to The Intercept in X Plus threshold velocity and the the multiply by 0.83 but in this case this is a generalization this is a simplification of the of of the mixure Velocity from a spinner in this number is very common to appear in ler especially in books that are old but this is what we call the velocity profile correction factor the interpretation softwares and are taking the velocity profile correction factor based in rainolds number yeah and as we saw rain's number has several variables that we are also taking from measurements and from inputs so in reality you will not have always this 0.83 0.83 Legacy number yeah Saudi Arabia yeah during production LS in Saudi Arabia very long time ago and at the end mixture velocity will be equal to velocity of the mix times the area and the area we're getting it after calculating from the diameter measurement from the caliper now there are some [Music] compliations that will affect how the spinner will rotate and the complication start as your well start becoming deviated why because as we see over here in the picture we have over here an oil entry and we have water coming from the bottom yeah so the main body of water is coming upwards but then the velocity the the oil starts segregating okay and as the oil starts segregating we start getting that the oil velocity is going to increase due to buoyancy and as the velocity of the oil starts to increase some of the water is going to be displaced downwards and this is what we call recirculation okay we can see over here more clearly with numerical simulation okay what you see over here in hold up map represented over here oil hold up basically oil hold up is zero is the blue color and as as the color becomes more hot this is a higher oil hold up or or this is the layer of oil basically you can see that it's occupying the least amount of the pipe yeah you can see that the mainly water is occupying the the the pipe in this case yeah in a 45 degree deviation H you can see over here in the velocity map that the oil velocity is very high while the water veloc is low and negative okay so we will have over here basically water recirculation yeah of course this water recirculation is going to be dependent on the mainly on the velocity of the flow it's going to be dependent on the heavy face itself the the also is going to be dependent on the diameter of the pipe so typically recirculation is going to be more obvious whenever you have large Pipes big size of pipe and you have low velocity in the wello yeah in Wells for example that have low prod production and you have a big casing it is very common to see recirculation effect now ER to complete the spinner application so what the spinner is going to do for us in production logging the spinner will be sensitive to any fluid entry it will help us to determine the a a quantitative mass flow rate H we will use to be able to obtain the velocity of the mix what we call multipass technique as you can see over here there is the log okay this is the production log and you can see all my spinner passes merged into one log yeah I can see here my down passes and my H up passes merge together and you can see that the the profile that the spinner of the spinner response is repeating yeah it is very important as a quality control by cable speeds have to be constant and my velocity my spinner profiles have to be repeating yeah so we can over here this is a single phas well and we can see over here the at the end our output should be the the velocity the the flow rate yeah is what we need to obtain at the end of the interpretation now we are going to look into a very important sensor also in production Ling which is the temperature so we have over here what we call an RTD and this is basically a sensor that is going to change its temperature his resistance based on temperature okay this is what an RTD is okay so what we why whenever we look into a well yeah we will have what we call a geothermal gradient okay and any entry or exit of fluid okay is going to alter this geothermal gradient okay it's going to change the geothermal gradient it's going to vary from the geothermal gradient so for example over here in the dotted line I have the geothermal gradient okay and I see over here first entry of fluid okay second entry of fluid and third entry of fluid and I see that my temperature is separating from the geothermal gradient okay so for example over here I have here a fluid entry okay at the entry okay the temperature start traveling upwards if I don't see any other temperature any other entry fluid entry my temperature tends to remain a parallel to the geothermal gradient and eventually it is going to come back to the geothermal gradient response after some time as it loses Heat so this is just a example of a temperature log is just a diagram okay and we can see over here again how the temperature separating from geothermal gradient yeah as we have any entry now for example here what are some examples of non- geothermal entries let's say I have channeling behind casing especially if it is water temperature will increase from your thermal gradient let's say I have a gas entry initially the temperature will decrease whenever I have the gas entry let's say there is High Rock friction okay in this case with with the production this tends to increase the temperature and away from the geothermal gradient so these are just some examples yeah over here I have some examples again so I have here an entry of water I see my spinner is responding also to the entry of water and my temperature is showing an increase I have an entry of gas again the spinner is responding to the entry of gas into the wello but immediately after the gas enters into the wello it happens expansion and this is what we call the jonome effect and as it happens expansion then we will have cooling effect so you can see that you have a sharp decrease in temperature initially whenever you have a gas entry now we have here another example let's say I have channeling of water behind the casing so over here my spinner is only indicating when the water already enters into the WBO but as you can see the temperature is already increasing when the water enters into the channel so this is one of the ways in which we can understand if there is channeling happening due to that cement in the case of gas again we have the same scenario a channel below the perforation and the gas is entering first into the channel so I will see a first cooling effect as expansion of gas happens inside the channel and then the gas enters into the wbor and I will see a second cooling effect so again we can understand here that I have gas flowing behind the casing okay so what are the temperature applications the temperature applications is basically you use it for Corrections on of the sensors that are present on your H production loging tool you use them also for fluid conversions okay you require the downhall temperature data for that H you use it to analyze if there is presence of flow behind the pipe also it can indicate what type of Entry which kind of fluid entry goes inside the wello as we can see where is different from gas entering into the wber from water or fluid liquid entering into the wber and in some conditions you could utilize temperature def flexion to calculate mass flow rate yeah but that's not a very simple as it depends on many factors but it can also be done okay so now we will go now to the pressure sensor so we can see over here a a pressure gradient in an static well yeah let's say we have segregation so I will see in the wellb a oil gradient and a gas gradient like in this example or if there is there is water as well segregating I could see in a wellb gradient when the well is in a static condition corresponding to water okay so the the pressure will help me to understand changes as well in the condition of the well yeah when I put the well to flow the temp the pressure is also going to start changing yeah so it's going to start decreasing compared to the static condition another thing that we do is that we merge all the passes of temperature that we did during the production log and we see if there is any variation of pressure every time I record a pass I don't want to have any pressure variations when I'm doing my logging survey I want that every time I do a pass up and down at different speeds my pressure remains constant because if the pressure is changing that is also indicating that the the wello Dynamics are changing so my response from the spinner is not going to be really representative of what is happening down so the pressure applications will be to understand the well is stable understand if maybe I have leaks in the two tubulars H to understand the gradients in the wellb in static condition due to segregation to be able also to be an input for my fluid properties at downhall condition so it will be also an input to the interpretation yeah my interpretation software and also we can understand some well operating parameters like we can do production logging for testing and in this case we can understand bubble point pressure and we can understand as well some factors we can derive some factors such as permeability and schin okay so we can do what we call multi-layer testing with production logging which is an advanced type of application from production logging fine now to enter into a well that is going to be producing multiphase we need to see some basic concepts okay so number one hold up what is the hold up holdup is basically the area fraction of the pipe that will be occupied by a phase of interest at any particular point in time okay then what is the water cut the water cut is going to be a surface measurement basically so the water cut will be whenever I have my total production at surface and I see what is the the percentage of of production of water from the total that I collected at surface okay this is the water cut so we should never ER confuse water hold up with water cut because they are completely different concepts and it is very common that people will confuse them and try to inter and this will lead to misleading interpretation of the production losss then we have what we call superficial velocity so superficial velocity is basically the velocity of a single phase flowing alone in the pipe then we have the mean velocity which will be basically the summation of all the superficial velocities especi when we have multiphase we will not be having just a single phase flowing in the pipe now very important we will have the Sleep velocity or a slipage velocity and basically this is the difference between phases flowing together so typically this is going to be the difference yeah so the this is a very important the slipage velocity is a very important concept then you have the singlephase flow rate which is going to be calculated by the average velocity times the area and the multiphase flow rate that is going to be phase velocity times the face area okay and the face area as we mentioned hold up is the area fraction occupi by the phase of interest in the pipe so face area is equal to the total area times the phase hold up so again water cut not equal to hold up and again percentage of Water by volume produced at surface from a well hold up as you can see in this diagram yeah so I see this diagram and I have water oil and gas flowing together if I take just a slice from my well downhole from my pipe I take a slice I an Analyze This slice okay and then I see how much of this circle is occupied by water how much is occupied by gas and is occupied by oil downhole then this is what we call gas hold up oil hold up and water hold up in this particular example we have that the oil hold up is 81% the gas hold up is 4% and the water hold up is 15% now it's very important then to understand that water hold up plus oil hold up plus gas hold up is going to be equal to one okay so 100 % and this is a downhall measurement we should never confuse with surface measurement okay now a slipage velocity basically a slipage velocity the phase different phase are going to be moving and different velocities so typically the light phase will be moving faster than the heavy phase due to density difference between these two pH so for example in this diagram we can see that the velocity of oil is equal to the velocity of water plus the slipage velocity okay and if we actually apply our equations we can see that the hold up of water is going to be equal to density of the mix minus density of oil divided by the density of water minus the density of oil okay the density of the mix is something that we are measuring the density of the oil and the density of the water downold densities is something that you get from PV data yeah from customer now slipage correlations there are many slipage correlations and different type of flow regimes and these LePage correlations were mainly derived by several people through experiments and empirical equations okay and basically over here the determination of a sleep as we mentioned before is going to be the difference of the velocity of phase light phas minus the heavy face so for example here if I have water and oil the slipage velocity is going to be equal to the velocity of oil minus the velocity of water okay so to be able to get the velocity of oil and the velocity of water we need to use the slipage correlations okay so you can see over here hold up is also going to be a affected by a slipage so if there was no slipage the velocity the hold up of of of the heavy phase is going to be linearly dependent to the velocity of the mix but in reality this is not what happens due to a slipage we don't have a linear relationship between the velocity of the mix and the hold up of the heavy face okay so for example if the oil is moving at a high velocity than the water in a pipe which is the phase that is expected to occupy more of this pipe a higher percentage of this pipe so in this case the the the phase that is going to be occupying a higher percentage of the pipe is going to be the water as the oil is Flowing at a higher velocity okay so this is just to show you a slipage velocity compared to density difference okay so this is also we say that the this is directly related to the the density difference but also H it will be a studied in flow Loops we will have another variations and contribution of conditions like the deviation like flow rates this is also very important whenever the sleep correlations are derived so here we have an example of one of these slipage models and this is what the doler model yeah so we have duckler H doler model usually is used for gas and liquid it's a gas and liquid liquid slipage model and we can see over here different type of flows considered by duckler yeah we have over here the oil and water superficial velocity plotted against the gas superficial velocity and depending on the velocity of every phase you will have a different type of flow regime for example let's say that my velocity of the gas is low and my velocity of the oil and water is also low then I will have what we call Bubble flow and this is the most easier to interpret let's say that now I have a relatively low gas velocity okay is increasing my gas velocity is increasing sorry and I have a relatively low ER water velocity then I can derive something called I can get into my well something called a slog flow and when I we have a well slogging is one of the most challenging things that we might need to interpret with production logging it's not going to be a straightforward interpretation then we might have a very high velocity of the gas and a very um medium to high velocity of oil and water and then we can start having something called me flow in which the bubble of gas are going to become very tiny and this might become a challenge for some of our hold up sensors now another very common and very used model during interpretation apart from Docker is Chet Chet is basically an oil and water slipage model yeah now there are many correlations same as I mentioned this is just in this H in this slide I am showing several correlations existing by liquid and gas and another correlations is liquid by liquid and liquid yeah and every interpretation software will have different correlations built in and you will decide as well which is the the best correlation that applies to a particular scenario that you have to interpret okay so now we are going to go to the hold of sensors the first hold of sensor that we are going to look into is what we call the gradio manometer to so what is a gradi manometer a gradi manometer is basically a differential pressure sensor over here I have a diagram of the gradi manometer sensor very simplified very very simplified so in the middle of my gradi manometer sensor this is where the sensor is going to be my differential pressure sensor okay and I have I will have a Bellow a v d will deflect with pressure yeah so in the bottom I can see that in one side of my h differential pressure sensor I have pressure two and in the other side of my differential pressure sensor I have pressure one and what I want is the differential between pressure two and pressure one okay this is what my sensor is looking at okay now who is pressure two pressure two now my sensor just to to to to complete my sensor is connected to a pipe internally in the tool yeah and this pipe is filled by a special silicone oil which we know its density this density is known okay and this is just a special type of silicone oil we cannot change it by another type okay it's just a particular type of silicone oil that we fill our tool with okay so then what who is pressure two pressure two we have in our in our tool we will have two ports that are going to be exposed to the wellbore yeah two openings in the tool exposed to the wello so pressure two is going to be equal to the pressure in Port a okay plus the column of fluid okay the column of fluid is given by density of the fluid in the wellb times gravity times the height and cosine of the angle yeah of the angle in this case this is a deviated well yeah plus the Delta P Co by the friction of the flow with the tool across the ports okay then we have that pressure one is equal to the pressure in the port a the top Port plus the density of the silicone oil okay this is pressure one times the gravity times the height of the pipe that contains the silicone oil cosine of the angle okay plus in this this this is pressure in one so then if I want to do my Delta P pressure in two minus pressure in one okay I will end up that this is will will be given by the density of the fluid minus the density of the silicone oil multiply by gravity the height okay between the ports cosine of the angle plus the Delta P due to friction at the end of the day what we want to obtain from the grum manometer what we want to obtain from the Gadi manometer and that we will use for interpretation will be the density of the fluid in the wbor the density of the fluid that is around the tool so in this case the density of the fluid is going to be given by the density that is read by the tool minus the density due to the friction the that we have with the the the the Delta P due to friction between the fluid than the to okay so this is basically the density of fluid at the [Music] end okay this is just exactly the same but put into another another form the equation and there are the the gradi manometer is going to be affected by several things that can happen to the gradi manometer measurement it can be affected by jetting something we call jetting effect it can be affected by something called kinetic effect and it can be affected by friction effect okay now G is going to change whenever the tool accelerates so that's why we will have that this fluid dynamics can affect the final output of the gradi manometer tool that will be the wello fluid density value another thing is let's say I have for example a very big amount amount of water and a very small amount of oil entering into the wello at the end this tool is giving me the total of the density of the wbor fluid so if I have a very very very small amount of one phase into a very big amount of the other phase for example very small amount of oil in a very big amount of water the density that my tool is going to be reading is going to be very close to the downfall dens it of water so if there is some error already in the measurement my the accuracy of the measurement is going to be low okay another thing that will affect the accuracy of the gradi manometer tool is deviation so as your well becomes more deviated the accuracy of the of the gradum manometer tool is reduced so at 62 Dees the accuracy of the gradi manometer tool is reduced by half okay so typically it the gradi manometer is not the best tool to measure hold up to derive hold up in highly deviated Wells this is just an example of jetting effect so jetting effect happens whenever you have like a very a perforation that is producing with a very high rate and you have one of the ports of your gradi manometer in front of this very high rate rate and yeah so you basically derive a very high turbulence acting on one of the of the ports of your tool so you will see a spike in your density measurement yeah you see over here a big spike on the density measurement then you might have the friction effect and the friction effect basically it is going to be caused by a s suction due to the fluids moving across your tool okay and in this case due to friction your density is going to be reading slightly more than the true density of the fluid but this effects some of them you can correct for because you will your tool will contain something called accelerometer so some of these effects can be corrected by the accelerometer and some other can be corrected as well by correlations yeah so now what are the graad manometer applications you want to understand what is the density of the fluid in the wbor okay you can identify entry of a light face into a heavy face or the opposite entry of a heavy face into a light face why because you will see a change on density okay wellber fluid density and at the end the the density of the mixture you can use it to derive hold up okay so for example I have over here you will I have over here my gradi manometer density and I have here water hold up okay in the y axis I have here a point that corresponds to having 100% oil okay now in this point I have zero water hold up because everything is oil and the density that I am plot using to plot this point is the downhall density of oil who provides this downhall density of oil this comes with the PBT data that my customer provided okay then I have the density of water my point the yellow point is basically 100% water Point why because I have 100% water hold up and this is the downold density of water again where this downold density of water is coming from is coming again from PBT data okay if I know the salinity and I know the the the downall density the downhall temperature that I am actually measuring with my tools I can derive what is the downhall density of water yeah then the Black Point is basically the what am I measuring this density in pink is the density that I'm measuring with my tool okay if I actually intersect the line that I have between my 100% oil point and my 100% water point I intercept it okay with the density that I am measuring with my tool and then intercept this point with the y axis this is basically the hold up of water in that particular depth so I already calculated hold up so I will be able to understand how much rate of a particular phas I will be having from that perforation okay now as I mentioned sometimes we need more advanced hold up sensors so one of the hold up Advanced hold up sensors that we have is what we call electrical prob how this electrical prob is going to work so basically you see over here there is the probe you will have like a little needle in this probe and you have the prob is actually attached to the tool in the case of our tools we will have four props okay attached to the caliper of the spinner okay for pro so you to have a good cover of the of the of the casing yeah now how does it works my tool is going to be conducting an electric current let's say I'm in water if I'm in water and this is water is salign then this current is going to continue as a closed circuit okay let's say a bubble of hydrocarbon comes to the prop what will happen with the current that is been conducted this current this is going to create an open circuit so what I will be counting is the bubbles of hydrocarbon approaching the probe okay in the case of hydrocarbon present in the wbor but I have no current being conducted in my tool through my prob and the body of the tool but let's say that a bubble of water comes into the into the ground of the prop and the and the tip of the prope I will have then a close circuit so the idea is that to be able to determine the water hold up I will calculate the amount of time that I have my tool in short circuit my prob in short circuit divided by the total time in which I am performing my measurement so basically I can count the bubbles of non-continuous phas and I can derive directly a measurement of water hold up okay so this is the idea of the electrical prop so what are the the benefits of this prop so basically that you can detect very small entries of non-continuous phase but again the only discrimination that you can do will be water from hydrocarbon that will be the Discrimination that this probe is going to do at this point this probe cannot tell you gas and oil yeah it will tell you just water from hydrocarbon okay so this is the other thing that this h a benefit from these props is that they are very close to the spinner measurement so the closer your sensors together the more representative that is going to be your measurement okay now the next tool that you have for hold up measurement is what we call the gas hold up Optical sensor tool so this tool is going to base on optical principle it's a very very what you can see over here in the screen is the prob also is going to be mounted in a centralizer we are going to be having four of these props so to have a radial coverage of the casing okay and the tip is really really very very very small the sensing diameter is around 0.4 inch okay very very tiny H needle that is going to be sensing this is made of sapphire crystal yeah and is having the shape of a cone in this case biconical two cones okay very you cannot really observe here because it's really a tiny very tiny yeah so now what is the principle the principle basically is related to Optics okay so if I have let's say I have in this case my tool is going to contain two items inside internally in the tool it's going to contain what we call photo diode and it's going to contain an LED basically a lamp small lamp a small lamp Okay light source these two are going to be connected to the probe to the optical probe the one that is actually facing the WBO by fiber optics and what I'm going to be doing with the LED is that I'm going to be shining a light through the fiber optics and this light is going to be present in the probe okay now depending on the type of fluid that is going to be around the probe the amount of light that can be reflected back to the fiber optics and arrive to the photo diode so if when we are in the presence of gas the gas is having in this case a refractive index of 1.1 and the a having a refractive index of one okay so if my light if the the the light that is in the probe is the probe is around gas I will have most of the light reflected back to my photo diode that is inside the through the fiber optic if I am in water less light is going to be reflected back to the photo diode and if I am in oil no light is going to be reflected back to the photo diode so again in this case what we do with this tool is discriminate the presence of gas from liquid okay I want to see gas hold up compared to liquid hold up okay so how am I going to determine the gas hold up the time that I have 100% of light coming back to my photo diode divided by the total time of my measurement okay this is what we call gas hold up and this is so now we have a measurement for water hold up and a measurement for gas hold up and we have an equation that told us gas hold up plus water hold up plus oil hold up is equal to one so now I can sort for a multiphase three-phase condition if I want yeah if I have a well with the three-phase condition okay this is just an example so I have over here basically my my Optical Optical tool can provide a waveform okay this is raw signal of my Optical tool and I see in the W for the point okay the points in which liquid drops it start basically hitting the probe yeah so in Iraq actually they used at the time of the of of the war they lost a lot of information okay and they needed to understand or to have some estimation of the bubble point of the wells okay so what they did this is an example of of some of this work that was done in Iraq they actually put the the go and they see at which basically at which pressure did they start observing bubbles of liquid okay so you can see over here when you can start seeing bubbles yeah so then you you you you you start getting basically bubbles of gas sorry so you can start seeing the the point at at which you're ER your oil starts at which pressure the oil starts liberating gas yeah at which pressure and then they manage to estimate bubble point pressure yeah now we are going to do go very quickly about what the interpretation software what are the inputs and what the interpretation software will give you as an output yeah so what are you going to require to make a good interpretation PLT interpretation you will require as much data as possible that you have from history of the well okay you want to for have for example the production the production rates you want to have production history you like to have cement bond logs to understand if the cement maybe is poor behind the casing you want to have good PBT data okay why because at the end of the day it is not just about the log acquired but you need to have a full scenario of what is happening with this way you need to understand ER all the history of the well so you can do a better interpretation of your tool okay so let's say in the case of a well that is producing two facee so what will be the inputs so you number one you are going to a d to to to have a production logging program very important to understand what is the objective to achieve with this production log yeah when we see the objectives is really to understand what are the entries from the perforations or or you want to identify a leak or you want to identify a cross flow you you want to understand what is exactly the objective from this production log you want to get as much well information as possible very important to get your production your wellb sketch and your completion sketch you if possible you want to understand some Reservoir information yeah whenever you see a cross flow and you have some Reser information from the reservoir you can understand why the cross flow is looking like that or why some a particular zone is producing more than another Zone and of course you want to have the pvt data okay so then you will acquire your logs your engineer loging engineer will acquire the logs and you as an interpreter and also the loging engineer are going to do a log log quality control okay this is number one once your log is having a good quality control and normally the quality control for example myself whenever the Schlumberger engineer is acquiring a l I do the L quality control real time while the engineer is acquiring the log okay so whenever he delivered the product already we have a good quality control on the log and I can tell him for example repeat a pass ER or make a station an extra station and so on another thing we need for the interpretation model my perforations and the calibration zones that I selected once I merged my spinner passes I have to check if I have a Zone with zero flow if you did a static H condition if you did a static measurement you will have zero flow okay also if in the case that you couldn't do a a measurement while the well was static you could you could consider sometimes the region below all your perforations okay although this is not very ideal then you are going to build your calibration plot okay you build your calibration plot and from there you get your threshold and the slope of your calibration line and once you do your calibration you will derive same as we saw in the spinner section your velocity of the mix so this is what the software is doing yeah and these are the steps even if you do it by hand with the help of excel these are the steps that you will follow the next step the selection of your model OKAY the selection of the model choice so the input from hold up okay do I have a the hold up tool is going to e either give me as we saw with the props a count or the gradiometer is going to give me the density of the mix okay and from the bubble count and density of the mix either either of of of of these two measurements I will obtain hold up okay once I obtain hold up and I add the slipage velocity okay and notice that hold up is an input also to a slipage velocity I will be able to obtain my downhall flow rates okay I already had velocity of the mix okay and of course I have to do a quality control of my interpretation and the quality control that we typically follow is that once we obtain from the interpretation our surface rates if there is available measurement of the surface rates real time we actually compare the surface rates that are being measured at Wellhead with the surface rates that we are obtaining from the interpretation and a good match is a a an indication that you have a good quality interpretation product okay and then if there is any discrepancy you can investigate what is the reason that you have a difference between surface rates being measured at Wellhead with the surface rates that you are getting from your interpretation okay so this is with traditional production loging let's say now what happened in horizontal Wells what are the challenges when you have a horizontal well so there are many challenges that you will find out whenever you deal with horizontal Wells you will have water that is going to be encroaching through fractures you might have a stagnant water or a stagnant gas presence Coatings okay your pipe your your your your well is not going to be perfectly straight horizontal you might have basically dips and and increases on the the deviation okay so it is very challenging environment for a production low not only that once you're well you start increasing in deviation your deviation increases and near to horizontal you will start getting fluid segregation okay so another another thing that is going to be challenging in a deviated well highly deviated well the the method of conance of your tool is going to be different to be able to to to drive the tool to the bottom of your loging interval you will require either Coil Tubing okay or you will require a tractor attractor is a tool that drives your loging tools okay to the bottom log interval okay now I want to show you something this is an example of how deviation will affect the flow so you have over here in blue colored blue this is these examples were obtained from something we call Flow Loop in our re Research Center yeah and you can see in the example of 90° this deviation you see that in this case so perfectly horizontal well you have that the velocity of the water is very similar to the velocity of the oil okay and you have a very nice stratification between the oil and the water the water water in blue the oil in red okay now if I have my well tilted at 88 degrees who is occupying the most of the pipe in this case if if if I have my well going uphill if my well is going uphill as indicated in our experiments in the floor Loop the oil is going to be moving as a very thin layer on the top of the well at a very high velocity and the water as it is moving at a very slow velocity is going to be occupying most of the pipe most of the area of the pipe okay now let's say now my my pipe is tilted down down hill as my pipe is tinted downhill like in the 92 degrees case we can see that the phase that is occupying most of the pipe in this case is going to be the oil and the face that is occupying the little area of the pipe is going to be the water as it is a heavy phase is going to flow Faster by gravity okay so the pipe is mainly occupy in this case or by oil so that means that oil hold up is going to be higher than water hold up so to be able to understand this type of segregation we cannot measure that with a normal spinner why because the spinner will be affected either by by the high moving oil or the slow moving water it's not really going to give us a representative measurement from the flow in the wellow okay because it's going to be highly dependent on the type of phas that is going to be moving and how how fast is going to be moving so in this case we have another tool this tool is what we call Flow scan imager okay and this this tool is going to contain mini Spinners these mini Spinners are going to be located at different levels in the wellb and it's going to contain also a different levels of the wello it's going to contain a water hold up measurement and a gas hold up measurement so we'll be able to localize our measurements in the different segregations that we have in the well so this is a real time information we get when we look this tool at different deviations and you can see for example that the at the 45 degrees we say that these big circles are my mini Spinners and the white dots is the position of my hold up water hold up and gas hold up sensors at different levels and I can see at 45 degrees I I I have a still sort of a bubble flow but I have my water suffering from recirculation yeah you can see the water moving down then if I am at the 90° condition I see that I have a nice segregation and basically you can see that the faces moving to at the edges of the pipe are are moving a little bit slower than whatever is moving at the center of the pipe but I have a perfectly segregated phase now the same examples as the flow Loop that we just saw in the previous slide let's say the 92 degrees 92 degrees down downhill we see that the water the heavy phase is moving faster and the light phase in this case gas is moving slower and is occupying mainly the most of the area of the pipe so gas hold up is bigger than all oil hold up and water hold up and this is real measurement Real Time by our [Music] tool so just to show you here so you can see over here the spinner being a conventional spinner is going to be affected by whatever phe is flowing in the world but H with this Advanced tool we can have a a spinner H located in the different part points of segregation of fluids yeah so this is the idea of this Advanced tool fine now that I show you or give you a taste of what is production logging I will show you some examples of real logs so we say that we can apply production logging also for Diagnostic in this case this customer wanted to understand which gas lift mandrels are active so to understand this which tools do you think that we used to be able to understand which gas lift bands are active so number one we want to correlate right so to correlate of course we will need a gamar and a CCL yeah at least a CCL has to be there now to understand if we have a a change in in in the velocity of the flow we will need a spinner the spinner can indicate some change in the in the flow but mainly which are going to be the sensors that are going to be the most sensitive to an entry of gas temperature because once there is an entry we have a cooling effect and press sorry density because as I have a bigger entry of of gas my density is going to decrease and the gas hold up can also help us into this measurement yeah if I have the gas hold up probe the optical probe I could actually see the bubbles of gas entering into the W so if we look at the L okay first I have my completion sketch very important in this Sky of analysis that I have a very nice description of my completion sketch against depth if you are going to interpret this is very basic okay you have to put it on your on your display second I have my spinner so I see that inside the tubing in this case the spinner is not rotating okay I see some spikes but this but in reality the choice of whoever did this log they selected a a full board spinner and typically the full board spinner unless you are using a turbine is closed inside the tubing okay other so so to be able to pull out out of the tubing so we will not depend here in this particular log on the spinner 100% although we see some spikes in gas lift Mandel in some of the gas Leaf mandrels but these spikes are mainly due to the change of the caliper on the on the gas leaf mandrel geometry okay but in this case the spinner is actually closed it's not rotating so forget about the spinner then I will look at the temperature so what is happening in gas lift Mandel number four and gas lift Mandel number three my temperature is just decreasing as I change depths okay but what happens in gas lift mandrel number two in gas lift Mand mandrel number two I observe some a slight cooling effect okay a slight change in temperature droping temperature then I continue to gas lift mandrel number one and I see a sharp decrease in temperature now if I look at the gradi manometer density mix okay the scale notice that is from zero the blue line to 1.2 so I'm reading close to one across all the gas lift banders number four and number three and the bottom in the wellb and then I see a drop in gas lift mandr number two a drop in the density so that means that something lighter is entering from gas lift mandrel number two then I see a sharp change in gas lift mandrel number one so my density is dropping a lot and is getting closer to zero yeah and then I look at my gas hold up measurement at the image from my gas hold up measurement I see in red bubbles of gas so my hold up over here in red this is gas entering into the WBO and then I see a very high amount of gas at the top whenever I have gas lifa mandrel number one okay and I don't see any other anomalies in the in the temperature so I don't think there is any other there is any leak in the tubing and I can knowe that gas LIF Mandel three and four are not active yeah they are inactive only gas lift mandrel number one and gas lift mandrel number two are active and gas lift mandrel number one is actually the one that has the highest injection H seen in this completion so this is one application of the production tools okay now this is another application for the Production Tool so this is basically to determine the entry of fluids from the perforations so this is a a a two-phase condition yeah so we have over here in red what you see in red these are the perforation intervals yeah this these tiny squares in red what you see in yellow is what we call calibration zones calibration zones Okay C for for my spinner calibration okay I didn't plot here the cable velocity but I have plot all my spinner passes yeah at different cable speeds when I plotted my sensors together I could identify that my spinner is increasing only in some perforations not in all of them okay so I see that I see an increase in the most bottom perforation okay now this well at the bottom of this well there was a plug and this plug is leaking so I can see that water is already coming from the bottom okay anyways I see that my first contribution comes from the apart from whatever is coming from the leak from the plug in the bottom I see that my first my most bottom perforation is making the spinner increase so I have here an entry of fluid okay then I see this the spinner remains constant until I go to this other perforation at around 13,050 okay this one and the one above it are showing increase in the spinner you can see that the one exactly at around 13,000 20 is showing the biggest spinner increase okay so we will think that this is the perforation that is contributing with most of the flow then I see that again my spinner remains constant okay across the other top perforations meaning that these perforations are not contributing at all so we have actually in total one two three perforations contributing in this well the rest of the perforations are not contributing are inactive then let's look at the wellber fluid density what is happening with the FL wellber fluid density first is close to one meaning that there is no hydrocarbon moving from bottom what whatever is leaking from the plug is water okay how I know that this water my customer already told me what is the salinity of the water in in in this formation okay I already know the temperature because I'm measuring the temperature with my PLT string so I also know I already know the temperature I also can can if I know the salinity and the ter temperature I can determine what is the downhall density of water and I compare with whatever my tool is reading okay so this is a quality control then I see that the density is dropping in front of this perforation that shows the first spinner movement so what will that mean if the density is dropping that means that I don't have only water anymore I have now presence of hydrocarbon entering to the system then I go to the next perforations and I can see that now my drop of density is higher so that means that I have more entry of light face into the system more hydrocarbon entry into the system okay when we do the interpretation we do what we call a we obtain what we call apparent velocity from the spinner yeah so this is my my velocity already this is a RPS and once the spinner calibration is done we will obtain the velocity of the mix so this is basically the velocity of the mix we have the density so with the density of the mix We and the downold densi is provided by the customer we can obtain hold up of water okay and we have as well over here our electrical probe our electrical probe is giving us directly the measurement of water hold up yeah we can see that below all the perforations water hold up is equal to one and we can so see that the hold up ER once we pass this the two other perforations that are producing it is around the the water hold up around let's say around a thir yeah and we see over here bubbles bubbles of hydrocarbon entering into the system and mainly the hydrocarbon entering from the oil entering from the two these two perforations at around 13,50 yeah so we have our water hold up and also the gradum manometer showing us the mixture fluid density so the conclusion is for this interpretation we have water coming leaking from the bridge plug we have hydrocarbon also entering from the bottom perforation and we have only hydrocarbon entering from the top these two active perforations so then you can take a decision of what you're going to do with this well so what you would if the cement is good behind the casing something that you would like to do is basically to set another Bridge plug and you will get rid of most of the water yeah still you want to evaluate if the hydrocarbon you're getting from the most bottom perforation is economic for you but let's say that I have no channeling behind casing my well is producing just water coming from the bridge plug and the water entering from this bottom interval but the bottom interval is still producing hydrocarbon so I will go and set another plug to be able to isolate that plug that is already leaking yeah so I will reduce most of the water basically in this case as you can see the the the the water hold up will be reduced yeah okay so I will show you just a another quick example of three-phase condition so again H what we see over here is the gamma aay to be able at the left the very left we have the gamma aay so to be able to put our log on depths okay we have in Black the perforations then we have the CCL we also use the CCL to put our log on depths as well then we have the caliper in green next next to the CCL and blue so we can see for example that in the casing color we have a different the caliper is showing the difference yeah in front of the perforation also we can see that the caliper is increasing a little bit and then we have the cable speed for this particular pass yeah here is the cable speed in red then we see an image this is an image of of the water hold up water hold up measurement coming from who water hold up measurement coming from my electrical prob so I can see sorry oops I'm very sorry for some reason I oops okay screen sharing has a stop why screen sharing has a stop share [Music] screen okay sh sorry I press something by mistake so you can see that the hold up is showing you a darker blue color wherever the water is the most also you will see a green line next to it that says water hold up okay this water hold up line is over there then you have the gradi manometer also indicating the wbor fluid density yeah the density of the mix so you can see that whenever the water hold up is decreasing Al also the density read by the or calculated by the gradi manometer is also decreasing so what does that means that means that I have hydrocarbon entries below all my perforation there there was only water yeah below all the perforations then I see that from the bottom starting from the bottom of my most bottom perforation I have the spinner increases okay and I have as well the the that the density decreases and the water hold up decrease the image that you see in brown is bubble count so basically when the image starts getting darker that means that you have a higher count of bubbles of the non-continuous phas so basically you have more bubbles of hydrocarbon entering into the system so I can see something very important here if I I look at my top perforation my top perforation is not active 100% I have that only part of my top perforation is active if I look at the track again why why is disconnected fine so what I was telling you let me just expand this okay this is fine the spinner which is this red the red curve that that is over here you can see that the top perforation is only producing from a very small interval and also you can see that most of the hydrocarbon coming from this H part okay how do I know that most of the hydrocarbon coming from that top small part of the top perforation because I see that my water hold up decreases to the maximum I can see that my density also decreases the most at this point and I can see that the spner as well increases H the most to this point yeah so H in this case so for this particular interpretation what was found out is that my top my top interval is producing mostly hydrocarbon okay if you can see the percentage of water Remains the Same starting from the bottom perforation yeah from the very bottom and the bottom perforation so there is no really input of of what water from the top perforation but mainly from the bottom perforation itself yeah you have some water entering into the system in the from the bottom perforation and some hydrocarbon as well entering from the bottom perforation but the top perforation is your main source of hydrocarbon and only part of the top of the top perforation so what do you think could be a a remedial in this well I would say that maybe a remedial could be if we do a reservoir saturation log that can actually see the formation if already if we still have behind perforation top perforation some oil presence we could actually go ahead and rep perforate okay and then we might be able to obtain a better production from the well now from the from the bottom entry you know that we have just a very small amount of water entering ER from from this uh perforation yeah producing 800 barrels of water compared to 150 barrels of oil I mean that will depend based on the on criteria that you have for your well yeah if you might want to isolate the bottom perforation or not well so this is all from my presentation I hope that it has been useful for you and H if H we can go now to the question and answer section please thank you engineer Maria for this inlining session now we'll move to answering some questions we have here seems like our audience is very interested to know your start in your career in the oil and gas industry would you like to tell us more about that H yeah so I am a mechanical engineer by career ER I specialize basically in cars I was supposed to work in the in the car manufacturing industry in my country but I joined slumberger I made my I went through a recruiting in my University forberger and I got selected as a field engineer I started my career as a warline field engineer in Egypt and I worked in the field in Egypt for four years and then I got transferred also as a field engineer to the south of Oman and then after that I left Oman after almost a year there and I I went to teach in the British training center in Scotland for three years and a half then after that I went to Sudan as a what we call Production Services domain Champion which is the same position that o right now is just that at that point I was a a what we call a guest or a junior domain champion in Sudan and now I am a what we call Senior three after senior it becomes Prin principal and after principal it becomes fellow okay so I am now a senior three Production Services domain champion and basically my I advise regarding case Hall logs in general yeah and perforation as well this is this is about my career wow that's very impressive okay moving on to the next question someone says um if velocity is an output and its measurement depends on ral's number which has velocity as an input uh then how is the parameter an output and an input in the same time okay so for Ros number what we have as an input is the velocity okay the velocity will be an output from the calibration of the spinner okay what we need to derive the the average velocity is what we call velocity profile correction factor so how do we derive the velocity profile correction factor first we are going to H obtain the velocity of the mix from the spinner calibration okay in which we convert the rotation rotational spinner the rotational velocity of the spinner into a linear velocity so the velocity of the mix is what is going to be an input to be able to calculate the velocity profile correction factor which is going to be dependent on the rain number okay okay uh that's about it for the questions today it was a pleasure having you um engineer Maria latisia Vasquez thank you for joining us this was definitely a very insightful session and thank you everyone for tuning in with us today engineer Maria would love to have you back thanks again welcome and anytime you have more questions you can direct them to a to Ahmed Mara and I will be very pleased to answer any questions you might have