hello good morning good afternoon and good evening on behalf of petro and Military search Hub I'd like to welcome you all in our SE session of the summer internship program my name is my aror a senior gazm patro chemicals engineering student SP Egypt young professionals member and I'll be your moderator for today so before we store it please keep the chat box professional and ethical and don't forget to to drop your questions in the Q&A section below so without further Ado let's welcome Dr Ahmed gari who will give us a session on hydraulic fracturing operations and Earth modeling Dr Ahmed Rari is a distinguished professional with over 20 years of experience in the energy and petroleum industry specializing in production enhancement services Dr ahmed's expertise in includes acidizing hydraulic fracturing geome mechanics geothermal energy carbon capture alization and storage and hydrogen Technologies he has successfully LED Pro projects for major companies like Apache Chev BP shell and totel currently Dr Ahmed a research manager at milit research Hub Dr Ahmed has a proven track record in publishing research on machine learning applications in energy his academic tenure as an assistant professor at merita College under scores his deep knowledge in production enhancement petrophysics and well logging analysis Dr Ahmed holds a PhD and Masters in petroleum engineering from Texas Tech University has published over 30 research papers and and received the distinguished Achievement Award from SP International in 20 21 now let's give a warm welcome to Dr Ahmed thank you so much Dr Ahmed for coming today today and the mic is yours may thank you very much for the nice introduction today we'll have the second lecture in our course introduction to hydraulic fracturing and as we know this is part of the summer training of petal and medit research up I received some good questions um written uh below the video uh of the first lecture on YouTube uh one of them uh one of you asked why we need to keep the injection rate constant why we need to keep the uh injection rate constant in the first lecture I I mentioned it is better to do our best to keep the injection rate constant and I said if you want to know why please ask me at the end of the lecture so I was planning to explain this by details in the third uh lecture which is the coming Tuesday but quickly I can tell you um the mathematical model we developed to evaluate hydraulic fractioning after we do the job to calculate or to get an estimate for the closure pressure or the leak off all these things we have an assumption in our mathematical model that the the the injection rate is constant so if you fail to keep the injection rate constant it means the mathematical model you are using to me to calculate the closure pressure and the leak off will be wrong and will not give you uh a result Mak sense okay so I want to keep the injection rate constant because this is one of the assumptions we made when we developed a mathematical model to predict the closure pressure and leak off coefficient or the leak of behavior in general okay and I will explain this more uh on on the coming Tuesday okay so today I I'm planning to talk about operations and mechanical a modeling so some of mechanics related to hydraulic fraction so let's begin the lecture today we will talk about the uh equipments the equipments we use in hydraulic fracturing also we'll talk about the materials we are using in hydraulic fraction and I will introduce what is principle stresses and finally we will talk about mechanical a modeling okay so before I I start talking about operations and the equipment we are using I wanted to differentiate between two there is a conventional hydraulic fracturing we used to do in Egypt in Iraq in Algeria and Saudi in India and China everywhere okay we call it conventional hydraulic fraction and this is when we track a conventional Reservoir like Sandstone formation for example most likely I will have a vertical well or slanted well sometimes a horizontal well and I will inject cross link gel something like jello but this Frack fluid which is the jello we are injecting we put cross link gel and I will show you a video for that is totally different with the Frack fluid we are using with Shale when we frack Shale most likely we use something called slick water so a slick water simply it is uh just a fresh water with friction reducer and some little additive okay and Dr Ahmed G will explain this more in his lecture because he will give you a lecture uh about Frack fluids okay so let's go back to Conventional fracking uh let's assume we have a Sandstone Reservoir and we want to Frack it to improve or to enhance productivity I have a well and that will produce let's say 500 barrel of oil and I want to double this number I want to make it 1,000 I want to make it 800 so uh one of the recommendations I get is why don't you hydraulically hydraulic Frack this well okay so in this picture you see the equipments we are using look to the mouse please look to the mouse please okay you will see two rows of big trucks see this is one row and here is a second row and there is some tubes in the middle here and there is a big equipment in one side here I will tell you the names of everything just wait few seconds okay so these two rows are pumps each big truck of these is um a pump we sometimes you call tlex Pump based on the the type of the mechanical type of that pump and this pump maybe 2,000 horsepower maybe 1600 hor power maybe 2300 horsepower but in average we can say roughly it is something like 2,000 horsepower okay so if you want to measure how many horsepower we are using in this operation you can count how many pumps in the location 1 2 3 4 five 6 7 and in the other side there is seven leg them so um um so we we have 14 pumps let's say we are using 12 of them and we have two as a backup or we are using 13 of them and we have one as a backup so we have on average something like 26,000 horsepower assuming I'm using 13 uh pumps but if the pump is 2,000 horsepower I will not use all of that most likely during the operation if it is 2,000 I will use let's say 1,500 I will not take it to maximum so you can multiply 1500 horsepower times 13 pumps I'm using then you can calculate how many horsepower you are using okay if you have an operation and you are using more than 20,000 horsepower this is a big job in Egypt or in Saudi or in Kuwait most likely the job is like a 10,000 horsepower I need that just five pumps six pumps seven pumps and that's it okay so this is uh comparing this job with what we have in the Middle East this is like a big one okay so these two rows I told you these are uh pumps and for sure whenever you see this red color what is the company running this job right mean the chat write me in the chat what is this company most likely halberton yes whenever you see this color most likely it is H okay especially when you zoom in and the you know this monitoring truck or you know you will see that the name of the company okay what we have in the middle these pipes we call it manifold we call it manifold so I have two rows of pumps and in the middle we have a manifold okay in this side I have something we call blender and the blender this is the heart of the operation I will use the blender to mix the Frack fluid with the chemicals with propan then after I mix them I send them through the manifold to the pump the manifold has two level one level we call it low pressure part then the low pressure pipes will take the fra fluid mix it with propin with chemicals with everything from the um from the the blender take it to the pump then the pump return it back to the manifold as a high pressure then the high pressure line will go to the whe head the whe head is here look to the mouse here is the whe okay so the manifold has pipes low pressure and has another pipe's high pressure how you know them the low pressure pipe you will see the hes we are using to connect the blender with the uh with a manifold you will find it rubber made of strong rubber it means this is low pressure but the pipes connecting the the the the pumps with the manifold that has high pressure you will find it steel pipe so whenever you look is it a steel pipe it means high pressure is it a rubber tube or a rubber hose this is low pressure okay you will see a lot of Tanks here behind this tanks maybe for water sometimes we have a big open open uh bit for water sometimes we put the water in the T in tanks okay so these tanks maybe for the water maybe for the sand maybe for the chemical things like that okay and you will have something here called the monitoring truck look to the mouse this white van we call it monitoring truck sometimes we call it control truck sometimes we call it data van based on the company each company give it a different nickname but this this monitoring truck you will find the job supervisor you will find the Frack engineer maybe the company man maybe some other maybe the fluid tick the guy who go get samples from the F fluid and do a quick testing in a small lab inside this truck and confirm that we are meeting the recipe we are meeting the properties um we were planning to have for this F fluid okay and the job of the team in inside this monitoring truck is to monitor and supervise the job they have a a radio like microphones they are talking to the team in the location and the supervisor can tell the team when to start pumping when to start pumping when to change from a stage to a next stage and so on okay so we talked about pumps we talked about tanks we talked about the manifold there is something called Frack head I told you here is the WB the Christmas tree and we have the Frack head here at the top of the Christmas tree here what is connecting the manifold with the Christmas tree so we can inject the the frag fluid and the prop okay there is something we call tree saver tree here means a Christmas tree the tree saver I will use it to protect my Christmas tree this Christmas tree for example rated as 5K it can handle up to 5,000 PSI pressure but the surface pressure in this job May reach 7,000 or 8,000 or 9,000 so how the Christmas tree can handle 8,000 PSI and it is rated for a maximum pressure of 5,000 and for sure if it is 5,000 if it is 5 K 5K means 5,000 okay for safety I will not use it above 350 3,50 sorry 3,500 I will not use it above 3,500 or maybe 4,000 maximum why for safety reason we don't want to get any accident in the location okay so how I will I can use this Christmas tree to handle injection pressure surface pressure of 8,000 if the Christmas tree not ready for that I will use something called tree saver it is a long tube and I will open all the vales of the Christmas tree and I will put this tube the tree saver from the middle from the top then it has two rubber cups will seal below the case ing hanger and this tube this three saer can handle up to 10,000 or 12,000 based on the its type so I will use a three saer to avoid changing the Christmas tree during the job because I during the production the surface pressure will not exceed 2,000 PSI so why I go and buy expensive Christmas tree that can handle 8,000 PSI or 2,000 or 10,000 PSI there's no need for that okay I hope um the basic idea of having Tre saer is clear sometimes we call it isolator okay I used to ask my students do you see do you see a workover r there is no workover R here you see a crane so we call this job rless operation rless mean there is no workover rig in the location okay and also I ask my students do you see where's the whe head here is the whe head easily you can find the whe head look to the two rows of the pumps look to the blender and in the other side you will see the wheel head and the manifold for sure will be in the middle okay here is our cover EG our cover rig is like a similar to a drilling rig but is smaller one stand of our cover rig most likely two tubes two pipes two pipes connected together this is one stand if you have a drilling rig one stand will be three pipes if it is big one for offshore maybe you will find it one stand is four drilling pipes but in general most likely drilling rigs the one stand is uh three drilling pipes but for workover it is only two this is how I used to look like 11 years ago when I was a Frack engineer fora Apache in Egypt behind me there is a lot of uh pumps and here is a manifold and for sure whenever you see the steel pipes this is it has high pressure for sure I get the picture before starting the job so it was safe environment during the job we cannot take pictures like this it is not safe okay now I will talk about hydraulic fracturing uh materials the materials we are using and as I mentioned Dr Ahmed G he's a PhD from Texas ANM and work a long time for Baker Hughes and now he's working for British Petroleum for BP and he is expert in Frack fluid so he will kill it he will explain it by all details and you will enjoy his lecture um very much okay so this is also a picture for a big job this is company for sure it is the silver not red anymore and again you can count 1 2 3 4 five six 7 eight eight trucks and the other side there's eight trucks so this is like a uh 16 trucks if each one is 2,000 so this is like a 32,000 horsepower ready in the location but for sure I will not use all of them because I need to have one one or two as the backup pumps also I will not use the pumps to the maximum value if it can handle 2,000 I will use I will run it let's say for 1,600 or500 or something like that okay this is also a reg operation you see the crane here and here is the whe head and the other side for sure you will see the plender and in the back uh you will see um tanks for sand and chemicals most likely they get water from um uh they have a big open bed and they put a lot of fresh water in it and they get the water from from it not from the tank so these tanks most likely you will find it for sand sand means propen and hdic fracturing when we say sand it means propin and I will explain what is po very soon okay and the mon in truck should be here this is a monitoring truck if you look at the mouse this is a monitoring truck by the way the monitoring truck must be in a location that easily you can see the whe head by the way I don't like this location for the for the monitoring truck do you know why because I see the crane in the middle and if you look from the monitoring truck window maybe you will not see clearly the wheelhead monitoring truck should be in a location like here look to the mouse location should be here when you look from the window you need to see the whe head very uh clear why because if there's any accident happen if there's you need to see all the location so this will give you better communication with the team especially if there's any kind of accident happen you need to uh stop the operation immediately okay so for for sure we use a lot of fresh water a lot of fresh water and we use a lot of KCl the salt you know the salt we are eating is sodium chloride and this is potassium chloride so what we have what we use in hydrulic fracturing in the conventional hydraulic fracturing is KCl also we use it in killing fluid or work over fluids so P this salt we use it a lot and mainly we use it to inhibit um Clays Clays willing okay we we will use a lot of gu and gu is something similar to beans and when we uh grind it it will become something like Star when we mix it with water it will make something like um a Milky shape like a something like milk okay when you add to it something we call cross Linker it will become like Zello it will become light Jello okay also I will use a lot of propen and propen this is um we call it sand and propon is small balls we injected with a effect fluid so when you stop pumping the fracture will try to close so the propan will keep it open the propan will be in the middle so the propan will not let fractures to close so I can keep the Improvement um I did for the conductivity of that formation so the formation will be very conductive because of the fractures and the pop I injected I will use a lot of chemical like cross linkers Breakers and I will show you a bit a long list of uh chemicals is the next slide here is Dr Ahmed G and he will teach you two lectures one about Matrix acidizing and a second lecture about fra fluids okay so the fracturing fluids in general the conventional fracturing fluids in general more than 90% of it is just water fresh water if you live in a country and you don't have a lot of fresh water maybe you cannot Frack a lot of WS if you live in Libya for example or if you live in Algeria for example and there is a a big reserve of um oil shale in Libya for example and big reserve of um Shell Gas Shell gas in Algeria and Shell Oil in Libya but there is not enough fresh water in Algeria there is not enough fresh water in Le ibia to Frack these Shale plates also there's no fresh water in Egypt so in Egypt we we have the the Nile the the River Nile but still not enough to do massive activities of hydraulic fracturing for Shale in the western desert in Egypt so this is one of the big challenges that in when we develop Shale we need to use a lot of fresh water in the United States there is huge amount of fresh water it rains all the year and there's big lakes so there's no problem in fresh water in the United States there's no problem in fresh water in China and in Argentina this is why these three countries are walking heavily in uh sh okay so more than 90% water about 9% sand which is prop and less than 0.5% is chemicals these chemicals may be surfactant maybe K maybe jelling agent maybe scale Inhibitors maybe pH adjusting agent maybe breaker maybe cross Linker maybe iron control maybe corrosion inhibitor maybe biocide maybe acid maybe friction reducer so it is complex recipe it is complex recipe and there's a lot of signs behind having good fra fluid and I believe Dr G will explain these things by details and you will learn a lot from him look to this picture look to the maps this is something like milk right how we get that we get it from this beans this beans we call it gu we plant the GU in India and neighbor countries to India so India Bangladesh Pakistan all these countries are good place to plant uh gu and again is similar to beans and it is a good business there you can make a lot of money if you are planting this gu because it is not only used in hydraulic fracturing we use it a lot in food in in manufacturing food so if you go to buy a lot of foods for kids cookies or any kind of sweets and you check the ingredients most likely you'll find gu part of it okay so here is a beans we grind it it become we make it like a powder very similar to starch we mix it with water it makes this thing similar to milk if you add Co Linker to it it will be like this picture like jello cross Linker gel of the Cross Linker will make the molecules stick together and make longer and longer and longer molecules it become polymer okay it will become something like jello okay please watch this video this is effect fluid and this guy job we call it fluid Tech the technician work with the Frack team in the location to confirm that they are making the Frack fluid the right way this Frack fluid we are using in in the Middle East and India and many other countries and Africa for example but in United States because most of the activities we are fracking Shale so we use something else called slick water and slick water is just water and friction reducer so it is not that jell it is um light fluid okay after you pump the Frack fluid and you fracture the formation you will crack the formation the same like this picture in the bottom here okay but when you stop pumping the fracture will close again because you you you are applying a pressure and that pressure exceeded the resistance of the formation and you you parted the formation now the formation is broken you have a crack in the formation but when you stop pumping these fractures will close because there is a there is stresses in the earth and these stresses will close the fractures again right this is the function of propin to keep fracture open I will use propin to keep fracture open after I stop pumping you will have different shapes of propin and different sizes different shapes and different size see we call this size 40 70 it is a very small this is 3050 this is 2040 this one is 16 30 so different sizes and you see whenever we have a big number like 4070 the prop become smaller actually 4070 it means a range for uh two saves a save this is what you see in the picture in the middle this is what we call a save okay and and this number this is the number of how many holes per one square in so one in square including has 40 holes and I have a second ser and one in square has 70 holes so the one that has 70 holes for sure the holes are smaller right so the propen can go through the s that has 70 hole per one in square sorry it can go through the one that has 40 holes in one in square and cannot go through the one that has 70 holes which is the smaller one so I would have a range so 40 70 this is a range of prop size what about 2040 I have two sves one save has 20 holes in 1 in square which is big holes so the prop can go through it and cannot go through a sa that has 40 holes in one in square so this is 4 24 is it clear I hope so okay so what is a propin use for we use propen to keep fracture open after we startop pumping why different in sizes because the fractures we are having as different opening Mouse so the width of the fracture will be different if I have a very narrow fracture the fracture is very tiny very narrow I need to use a very small prop and this is I need to know exactly the mechanical properties of the formation especially the youngest modelist if I have a high youngest model let's say 10 million PSI youngest models or 8 million PSI youngest models I'm expecting a narrow fractures for example so I will recommend smaller propin and the propin itself most likely it need to be six times smaller the diameter of the of one propin should be six times smaller than the opening of the fraction so most likely when when we do modeling we model it like this six times of less smaller than the opening of faction okay think about the prop size and youngest modulus I already answered yes I told you whenever we have higher youngest modulus I need to use smaller prop okay also think about the settling sorry the prop strength the prop strength if we have minimum horizontal stress let's say 7,000 PSI and maximum horizontal stress 8,000 PSI and overburden 10,000 PSI for example okay and I have a prop will be crushed when you apply 5,000 PSI on it it means this is not a good propin this propin if you inject it will get crushed inside the formation and it become like a powder and it will plug the fractures you made very bad choice so you need to select a propin can resist the stresses in the formation and can stay uh in a good shape without any crushing for a long period of time so you need to apply a crushability test for the pent you are using and be sure that this pent can handle the high stes or theis in in that formation without getting crushed okay now I will introduce the principal stresses what is principal stresses and we will talk a little bit about uh some uh Rock mechanics Basics why this is important for us as a petroleum engines we drill horizontal Wells and we need to know what what should be the the best direction for the horizontal section we drill the horizontal section with the minimum horizontal St direction or with with the maximum the maximum horizontal Direction which one is better okay also I want to know if I will Hydra hydraulic fracture a horizontal well the fracture will grow to which direction so these directions of the the optimum horizontal well direction or the optimum hydraulic fracturing Direction I relate this to the direction of the minimum and maximum and we will see which one is better now I mean after this slide so first let me introduce what is principal stresses there is a lot of stresses inside the earth we are Drilling and we can summarize the stresses in the uh Reservoir or or in the earth we are drilling into three principal stresses they have 90 age with each other so think about something like X Y and Z and one of them is vertical because one of them is the overburden overburden is the weight of the Rock and this weight of the rock apply uh the weight will be perpendicular or pointing to the Center of the Earth the same like the weight of your body if I'm asking asking you how weight you are how how you know what is your weight you may tell me you are 8 80 kgam 70 kg 65 kg 75 Kg for example okay if I will ask you what is the direction of your weight because of gravity your weight will point to the center of earth right so over burden is the weight of the Rock at a specific depths so we know its direction it must be pointing to the Center of the Earth right right how to get the magnitude of the overburden you can integrate the density log when you get a class in will logging you will get something called density log and each one foot or each half foot I will measure the density of the rock I can integrate this density and get the weight and keep adding this weight together so I can get the weight at a specific depth and at that depth I will say the weight of the Rock at the depth this is the overburden stress magnitude this is the value and the direction is pointing to the Center of the Earth because it is weight okay and I have have two horizontal stresses most likely they don't have the same magnitude one of them will be a little bit bigger the bigger one I will call it the maximum horizontal stress and the smaller one I will call it the minimum horizontal stress so assuming I have a normal fault system I have a fault here if you get a class in geology you will understand this part easily and you see the right side of the fault will sled downward will move down why it is moving down because the overburden magnitude is greater than the minimum and the maximum horal stress so the faulting system here we will call it normal faulting system I will have a crack and the right part of the rock will move downward okay if if I have a fault and the minimum horizontal stress magnitude and the maximum horizontal stress magnitude both of them greater than the overburden magnitude the movement of the fold will be upward the right side will move upward why because the horizontal spaces are bigger and it will keep carrying the right part out of the Rock and pushing it up so I know that in this case the overburden is a smallest in magnitude okay I will call this thrust fold or reverse fold why reverse because this is the opposite of the normal fold what about if you have the over birden magnet itude not the largest and not the smallest just in between the magnitude of the minimum horizontal stress and the maximum horizontal stress so the movement will be the two parts will move parallel to each other we call it strike slip fold strike slip fold so these three different fold system this is that for sure there is more types more fting systems six or seven but this is the most common three and this is enough to explain what is overburden what is maximum horizontal stress what is minimum horizontal stress okay so for each one of these three stresses I need to know two things I need to know the magnitude I need to know the direction why because it is a vector guys let me ask you this question in the chat what is the difference between pressure and stress write me in the chat what is the difference between pressure and stress write me in the chat the difference between pressure and stress thank you very much much I get a perfect answer at the beginning who's this guy let me get his name arai Roy thank you very much pressure is scaler stress is a vector this is the right answer so we measure pressure by PSI pound per square inch per inch square PSI and we measure stress also by PSI so what is the difference pressure is a scaler I when you talk about pressure I need to know exactly the magnitude that's it I don't care about the direction because it is a scalar value I don't care about the direction I care only about the magnitude the value and most likely I will use pressure for fluids like liquids gases but stresses most likely we use it with solids but the the what is very important for stresses is it is a vector it needs two things it needs a magnitude a value and needs a direction magnitude and direction we call it vector so stress is a vector pressure is scaler and we measure both of them uh using the same unit which is a PSR so for each one of the minimum of the of the principal stresses The three principal stresses I need to know the direction and I need to know the magnitude okay so to get the direction of the minimum and maximum horal stress we agreed that the overburden is too easy we know the direction it is pointing to the Center of the Earth we know the magnitude just go and integrate the density log you have so I will focus now talking about the minimum and maximum horizontal stress because this is uh my challenge now so to get the direction I can use diol Sonic I can use a dipole Sonic log to to get the direction of the minimum maximum horizontal stress I can use the caliper log I can use the image log the FMI I can use a website called word first map you enter the location and they will give you a map like the one you have it in the middle here and it will show you all the folds near the region and from the direction of the fold you can get an idea about the direction of the minimum and maximum stress also I can do something called failure analysis you can say a break down and collapse in a will Bo and this is very helpful to um to get the magnitude of the maximum St because this is it is very uh difficult and complicated to get magnitude for maximum to get the magnitude for minimum or a good for the minimum horizontal stress is so easy and there's a lot of different ways but to get a good estimate for the maximum horizontal stress it is very very complex and challenging okay look to the specture this is a Bo and we use this during drilling if the mud weight or mud pressure very low you will get collapse you'll get break out and the break out look to the second picture from the left if you make a line a line on the two red SS here this is the direction of the minimum horizontal stress this is the direction of the minimum horizontal stress if you keep increasing the mud pressure or the mud weight you will get you will fracture the willb you will get lost circulation you will fracture the willb and this structure will be perpendicular to the minimum minimum horizontal St Direction I like to say perpendicular to the minimum horizontal stress this is more accurate than saying with the direction of the maximum horizontal stress okay so it is better to say the hydraulic fracturing go in a direction perpendicular to the minimum stress okay and and in the left you see this is the uh caliper log and here's a trajectory and here's the first the surface casing here is the second and in this world we have four casing not three we have four four level and whenever you see to the caliper log you can get an idea about the location that we have a lot of uh breakout so you can get an idea about um you know uh using the caliper you can get an idea about the direction of the minimum and maximum too it is better if you have um a lot of this information available to uh do it using different ways so you can confirm exactly the direction of the minimum and maximum it is better to use different ways to confirm uh the direction of both minimum and maximum of if you get one of them 90 Dee this is the second this is the other one please answer this question in the chat which one will be better in production if you drill a horizontal well with the direction of the maximum horizontal stress like the first one to the right and you drill the second one with the direction of the minimum horizontal stress which one will produce more the one you drill with the minimum horizontal stress or the one you will drill with the maximum okay so most of you get it right so whenever we dra the horizontal well or the horizontal section or the lateral with the direction of the minimum horizontal stress this will give you more production better production why because when you do multi-stage fracturing the fractures will be perpendicular to the direction so we will get nice fractures like this you can get as many as possible you can make 20 fractions 100 whatever you want and when you frag this way you will get more contact with the reservoir so you can produce more okay so which one so I will call look to the mouse so the world to the right I will call it one the well to the left I will call it two so this is one and this is two which one is easier to drill one or two which one is easier to drill drill will one or two some of you get it right some of you get it wrong so please remember this well number one the one to the right I can drill it easier the rate of penetration will be faster and higher because I'm drilling I'm pushing against the minimum horizontal stress I'm going in a direction perpendicular to the minimum so I'm pushing against it so it will be easier to drill but drilling is just two weeks three weeks of the world life okay so if I'm drill well number two was the direction of the minimum horizontal stress and I can handle some problem let's say I will get delay one or two days extra for example to drill it that way but the production time of the 12 will be 10 years or 15 years or 20 years so if you compare 20 years of production of better production with one or two days or one week more and drilling it is nothing so even we know that dilling with the direction of maximum horizontal St will be easier but we prefer to drill horizontal Wells with the direction of the minimum horal stress because later we will frag these uh uh laterals and we will get better production okay here is the same thing I will drill the horizontal well with the direction of the minimum horal stress and this is what we do everywhere finally I will talk about some mechanical properties and I will continue on Tuesday talking about mechanical model I will try to finish quickly so I give you more time to um ask questions so there is a company called GMI GMI uh it is a company uh founded by Dr Mark zubac and Dr Dan moose long time ago the the um Mark zubac is maybe the most famous guy working GE mechanics he's a professor at Stanford University he he already retired and then moose was one of his students and they established a company called gmr okay geomechanics internation later Baker Hughes bought that company so uh jmi now is part of use okay so to calculate the vertical stress to measure the vertical stress the overburden you can integrate the density log as I told you to get the P pressure you can use rft or DST or you know there's a lot of ways to do that to get estimate for least principle stress which is if it is normal f system it will be the minimum horizontal stress I can do uh leak of test or extended leak of test or mini Frack or I can you know check the loss circulation of ballooning all these things can give you an idea about um a good estimate for uh the least principal stress for the maximum horizontal stress I need to do something called willour failure analysis and this technique developed by Dr Dan moose long time ago it was his PhD at Stanford University like maybe 30 years ago or maybe 40 years ago and um what I can tell you this technique also very complex not easy not easy to do because you need a lot of data a lot of failure data uh willb failure data in the same location let's say hundreds of Wells or tens of wells and we most likely will not have this information so it is a good technique but most likely needs a lot of input so most likely you you cannot you will not have have these input so you cannot apply so we we used to give some estimate of what we call it like a [Music] um some estimat like I will assume the maximum horizontal stress is 1.1 minimum horal stress or 1.2 minimum 1.3 something like that so we call it like a sensitivity study we we we do some Sensi to get a good estimate for maximum oral stress and for work strength you need to take Coes and take it to the r mechanic lab and do some uh test there so I will use a lot po ratio and youngest modulus and minimum horizontal stress so poon ratio simply it is a lateral strain over the longitudinal strain look to this C look to this uh cylinder shape when you apply a force from the top and bottom a stress apply stress from the top and bottom okay so the length of the cylinder will change and the diameter of the of the cylinder will change when you divide the lateral strain over the longitudinal strain you will get something called poson ratio this is a name of a French scientist Liv in the 18 18th century it was a very famous French scientist at that time okay and the person ratio value must be something between 0 and5 remember this must be between 0 and .5 if someone told you person ratio is 7 or8 it means there's something wrong don't talk to this guy again he didn't know what he's talking about so it must be something between 0o and5 this is the range of RA okay I can use this equation to calculate the minimum or to estimate the minimum horizontal stress new this is not V this is new the Greek letter new and new it is the pation new over 1 minus new and here is the sigma V this is the overburden minus Alpha uh p p is this is the PO pressure and Alpha this is something we call it bio Conant bio also a name of a scientist French scientist and bio Conant most likely it will be something less than one so let's say 789 one and most likely they will provide this value to you they do some lab testing and they will provide this value to you okay and sigma T at the end this is something comp we call it h tectonic stress and most likely an expert will give you an estimate for that value too so this equation can give you a good estimate for minimum horizontal stress or you can go ahead and just do well testing you can do many Frack test where we check the extended L of test or the L of test you have during Drilling and we can uh get a good estimate for that here is the youngest models the youngest models when you apply stress on a material and you get a strain and you keep recording when you change the stress how much the strain you get and keep changing stress changing get 10 values for let's say applying different stresses and get the strain you can draw this shape so you can keep doing this until the material get broken and fail get fractioned so when you divide the stress when you get the stress over strain we call this youngest models so youngest models is a stress over strain strain is unitless strain has no unit because it is a lens over a lens a lens over a length millimeter over millimeter or ctim over ctim so it is unitless they will cancel out okay so the unit we use for youngest models it is the same unit we use for stress so youngest modulus we measure it by PSI the same unit we use for stress okay we have a big problem in hydraulic fraction ing not only in hyic fractioning in any Rock mechanics project or geome mechanics project we are doing and we need to do mechanical s model we have something we call Dynamic youngest models and static Yus models in oil and gas business most likely you will have the Sonic log the compressional wave and the shield wave and from them you will get Plus on the ratio and you will get youngest models Dynamic youngest models okay so the dynamic youngest models you are getting from the Sonic I would call it dynamic dynamic youngest models but this is not the youngest models I need to have in um my hydraulic fraction design when I design for a hydraulic FR job I need the static youngest model the value I receive from the rock mechanic lab when I give them from my formation then they do the testing in the lab and they give me the report hey here is your youngest models to the one I get from the RO mechanic lab when they test do the tri aial test on course we call this static youngest modelers but most likely you will not have this this is very expensive and most likely they will not core most of the wells you are working on so you will have the Sonic log and you will get only the dynamic models before finishing your work or to do your work your your frag design you need to convert the dynamic youngest models into static youngest models you will find hundreds or maybe thousands of different equations to convert Dynamic to static I listed here maybe 17 or 25 different equations to conver Dynamic to static English models which one of them is right I believe all of them are wrong why you need to develop your own local correlation for the field you are working on or for the area you are working on you need to develop your own local correlation to convert Dynamic to static engus models so you can get something you can trust maybe you have uh you your company qu some wells in the area this will be very valuable for you so you can use these values or maybe a neighbor company working in the same area they published a paper and they did De quote some wells and they uh publish the estimates they get for static models okay but anyway you need to convert Dynamic you need to find a good way to convert Dynamic English models to static models and you need some experience to do it right so please um when a project like this assigned to you you need to talk to an expert in your company like a supervisor so he can guide you what should be the right correlation to use to convert Dynamic to static K models it is very complicated you would get a lot of headache when you work on there but anyway whenever you get some experience you will know how to handle this okay are you already I have some questions for you let me check how to start guys there's five questions please go ahead and answer them so you should you should see five questions and your screen please go ahead and answer them I will give you like a minute then I will start answering the question with you okay so I will stop the I will end the uh poll now and let me answer the questions with you so the first question what is the primary cause of formation damage in petroleum reservoirs a excessive oil production Drilling and completion operations High Reservoir pressure D natural gas injection what do you think should be the right one so the first source of formation damage is drilling operations Drilling and completion operations this is the the most important reason for formation damage so the right answer is B Drilling and completion operations question number two which of the following is a common method to mitigate formation damage a increasing production rates B hydraulic fracturing c acidizing d using havior Drilling Fluids the right answer is acidizing guys hydraulic fracturing not fixing the formation damage hydrulic fracturing P pass pass ing the formation damage it is different by passing the formation damage means we are creating a new highway but the formation damage will stay as it is but acidizing when we use acids or acid treatments most likely we we we do this to dissolve the formation damage so acidizing we do it to remove the formation damage question number three in hydraulic fracturing what is the purpose of using propin I told you propin we use it to keep the fracture open to increase fluid viscosity no to prevent the fracture from closing yes to reduce formation pressure no to seal the will B no so the right answer is to prevent the fracture from closing question number four which type of acids which type of acid is commonly used in acidizing treatment to remove formation damage uh caused by carbonate scale I know that we did not explained this before but remember the most famous acid we use is HCl especially I have a carbonate scale so HCL can dissolve carbonate so hydrochloric acid this is the acid we are using Okay so the other choices soric acid acetic acid nitric acid HCL is the most common one for carbonate Scapes question number five and the last question what is the primary goal of hydraulic fracturing in unconventional reservoirs unconventional reservoirs like um Shell Gas sh oil like tight Sands like uh PID methane very tight carbonate if the permeability very very very small and we measure it by Nano we call this unconventional okay Choice number a to increase Water Production to enhance oil and gas recovery by creating fractures that increase permeability to reduce the porosity of the rock to stabilize the willbo the right answer is to is to enhance oil and gas recovery by creating fractures that increase permeability guys there is a mistake in this question it is not right to say to increase the permeability I'm increasing the conductivity of the formation not increasing permeability in hydraulic fracturing I am not increasing the permeability of the formation the propin has higher permeability and because of the propin and the fractures I am increasing the conductivity of the formation okay so uh please correct that okay so uh that's it for today I will check if there is any um you know questions I can answer I can take one of two questions then we can close so I will take just one question so if I have youngest modelers on already um well processed it static K modulus no no no no the the youngest models you get from the Sonic log this is dynamic why dynamic because I use the sonic wave and the sonic wave has high frequency and small magnitude we call this uh dynamic dynamic models but when I when you do the tri aial test in the RO mechanic lab you apply High magnitude and small frequency this is the opposite and this is similar to what we do in the real hydraulic fraction so what we need to have in in to design a hydraulic FL job is a staticus models but unfortunately most likely you will have only the dynamic Kus models because you have the Sonic plug and you don't have uh CES and you don't have a report from the mechanic lab after testing these CES so most likely you will have the dynamic models and you need to complete your design you need to find a way to convert Dynamic to static English model okay thank you very much uh we will continue talking about Hy fracturing on uh Tuesday please if you have any questions I did not answer today write it below the video on YouTube I go to the YouTube video after we post it and I read all the questions below the uh YouTube uh video so please if you have any questions we did not answer today leave me that question under the YouTube video thank you very much and see you Tuesday