[Music] hello everyone welcome in this video we will describe and relate the distribution of active volcanoes earthquake epicenters and major mounting belts of the plate tectonic earring [Music] previously you learned that the earth's crust is divided into segments of landmasses gold plates and these plates move constantly in various ways known as play tectonics now what are the bases of scientists in dividing the earth's lithosphere into plates now let's take a look at these lessons let's start with lesson one distribution of earthquake epicenters in the world [Music] earthquakes are vibrations caused by rock breaking under stress every day millions of tiny earthquakes happen but we can only feel those who are strong enough now how are earthquakes distributed in the world and how are they related with plate tectonics let's take a look at this picture showing the distribution of earthquakes around the world the red dots represent the location of earthquakes epicenters what do you notice before we discuss this let's ponder on this simple activity and try to answer the questions that follow if we have the map of the lithospheric plates and place the map of earthquake epicenters on it what do you observe now pause the video for a moment get a paper and try to answer the following questions [Music] one how are earthquakes distributed in the world [Music] number two where are they located [Music] and number three why is it important for us to identify areas which are prone to earthquakes one of the evidences of plate tectonics is the distribution of earthquake epicenters in the world in here the yellow dots represent the earthquakes as you can see earthquakes are not randomly distributed in the world they tend to occur in the boundaries of each lithospheric plates countries along the blade boundaries experience over a thousand earthquakes yearly philippines for example is located in one of the most active tectonic settings in asia earthquakes in the philippines occur along the philippine trench the manila trench the philippine fold zone and the valley fold system the philippine trench the primary source of earthquakes was built by subduction of the western edge of the philippine plate beneath the eurasian plate this trench extends from south of the mindanao island to the luzon island in the north several numbers of destructive earthquakes have occurred in every part of the country the central luzon earthquake in 1990 with a magnitude of 7.6 was the largest seismic event in the philippines not all earthquakes occur at plate boundaries there are interplayed earthquakes that occur because of the stress in rocks being released this is what caused the 1968 meccaring earthquake that happens in western australia which has a magnitude of 6.8 this caused major damage in structure and infrastructures scientists are researching on ways to predict the occurrence of earthquakes but until now there are no devices that can measure when or where an earthquake may occur and that's the end of lesson one congratulations now let's discuss lesson two distribution of active volcanoes in the world a volcano is an opening in the earth's crust through which lava volcanic ash and gas escape beneath a volcano liquid magma containing dissolved gases rises through cracks in the earth's crust now where are most of the volcanoes in the world located now let's take a look at this picture showing the map of active volcanoes in the road areas shaded with red are places on earth where most number of active volcanoes are located what do you notice before we discuss this let's ponder on this simple activity and try to answer the questions that follow let's say we have the map of the lithospheric plates and place the map of active volcanoes on it pause again the video and try to answer the following questions number one how are volcanoes distributed [Music] number two where are they located and number three based on the map mention a country that is unlikely to experience a volcanic eruption [Music] volcanoes are produced by plate tectonics as you can see in the illustration the places on earth where most of the volcanoes were formed mark the boundaries of each lithospheric blades most of the number of volcanoes can be seen on the plate boundaries this happens during collision of two plates if you are also going to notice most of the active volcanoes are located on the pacific rim of fire it traces boundaries between the plates like the pacific philippines juan de fuca cocos and the nazca planes countries lying near the plate boundaries are prone to some geologic events like earthquakes and volcanic eruptions caused by the continuous movement of the plates philippines which lies on the ring of fire also has experienced volcanic eruptions that causes destruction to the lives of the people and even to its environment countries lying far from the blade boundaries do not have volcanoes therefore never experienced a volcanic eruption and that's the end of lesson two now let's discuss lesson three distribution of major mounting belts in the world mountain range is a group or chain of mountains located close together mounting belts often share the same geological origins mounting ranges have similar form size and age the process of mountain building is called origini this comes from the word auros which means mountain in genesis means creation now let's study this illustration showing the map of the major mountain belts in the world areas shaded with red are places on earth where mountain ranges are located what do you notice before we discuss this let's ponder on this simple activity and try to answer the questions that follow let's have first the map of the lithospheric plates and place the map of the major mounting belts on it study the map carefully and answer the following questions number one what can you say about the location of the mountain ranges and number two how will you relate the distribution of mounting ranges with the distribution of earthquakes and volcanoes [Music] the earth's major orogenic belts are the circum pacific and the alpine himalayan orogenic belts these are the major mountain building belts in the world mountain ranges are formed by a variety of geological processes but most of the significant ones on earth are the result of plate tectonics most mountain ranges have been formed at convergent boundaries where two plates move towards each other [Music] formation of major mountain belts in the world let's start with the formation of the himalayan mountains the himalayas were formed when two continental plates collided in gen plate moved towards the rest of eurasian plate during the last 70 million years the leading edge of the indian plate have been thrust beneath the edge of the asian continent in the coalition zone the asia overrides india and is therefore uplifted and folded to form mountains mount everest of the himalayan mountain is the tallest mountain in the world at a height of 8 848 meters up to this day indian plate is still moving and himalayas are still growing formation of andes mountains the undeaths were formed when the nazca oceanic plate moved towards and subducted on the west part of the south american plate and this mountain is also considered as the world's longest mounting ranges now let's compare the location of earthquake epicenters active volcanoes and mountain ranges as you can see these geologic features and processes are all products of moving lithospheric plates when lithospheric blades interact earthquakes volcanoes and mounting belts are produced [Music] and that ends our lesson i hope you learned something today thank you for watching [Music] bye