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Session 51 : July 2018 Mock Test
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Sumant Kumar
B.Tech NIT Allahabad. Scored 136 & 120 consecutively in UPSC Prelims. YouTube Channel "Crackers' IAS Academy". Telegram - "CrackersIAS"

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thanks for these awesome lectures, Sir
  1. A McKinley (6,194 m)t A Elbrus (4,810 m) A Everest (8,848 m) (4,884 m) KosciuszkO A Kilimanjaro A (5,895 m) Puncak Jaya A AconcaguaA (6,961 m) (2,228 m) Vinson (4,892 m)

  2. At trench Ocean floor destroyed - melted in mantle Oceanic crust heavier than continental crust *Ocean floor act like conveyor belt Ocean floor - cyclic process 300 ml years Mid-oceanic ridge Trench Ocean Subduction Continental ithosphere Oceanic lithosphere Cold Convection cell pwelling Hot Outer core Mantle Inner core

  3. In which one of the following oceans the Diamantina Trench is located? a) Pacific Ocean b) Atlantic Ocean c) Indian Ocean d) Arctic Ocean Pacifle Ocean MARIANA TRENCH NORTH MARIANA ISLANDS DEEPEST , POINT PHILIPPINES AUSTRALIA


  5. Palaeo-Magentism *Magnetism of rocks along MOR Magnetometer -Magnetic parallel stripes- normal and reverse magnetic profile * 1St Carlsberg ridge - Indian ocean Mid-oceanic ridge Oceanic crust Mantle

  6. Molten lava get polarity geomagnetic field of that period-Solidify Ocean floor-magnetic tape Magma A. Period of normal magnetism Magma B. Period of reverse magnetismm Magma C. Period of normal magnetism

  7. Convection cells = force behind drifting of continents Ridge Push Lithosphere Mantle Convection Cell Convection Cell Outer core Inner core

  8. the Ocearn Floor Volcanic Island When volcanoes on the ocean floor erupt, they can create mountains so high that their peaks break the surface of the ocean. As the lava cools and hardens, an island forms Mid-Ocean ridge The mid-ocean ridge consists of many peaks along both sides of a central valley. This chain of undersea mountains runs all around the world. Continental slope A steady indine marks the continental slope. Continental slopes in the Pacific Ocean are Continental shelf This gradually sloping area width varies from just a few 1,300 kilometers from shore. borders each arth's oceans are thousands of kilometers wide. To show the width of the ocean floor in this illustration, the vertical and horizontal steeper than those in the Atlantic Ocean. Note: Because the kilmeters to as much as vertical scale is exaggerated, the continental slope in this illustration appears steeper than it realy is scales are not the same. The vertical scale, showing depth, has been stretched. The horizontal scale, showing distances, has been squeezed. Continental shelf Continental slope Mountains whose peaks do not break the surface of the ocean 6 water above them are E called seamounts Abyssal plain Thick layers of sediment, formed by the sunken remains of dead organisms from the surface cover these vast, flat plains These canyons in- clude the deepest spots on Earth. The Mariana Trench in the Pacific is 11 kilometers deep. Width of ocean: thousands of kilometers

  9. Rifting makes oceans widen Continental plate 20mm/year Rising material

  10. MOR Mid Oceanic Ridge *Rising limb of current breaks the Ocean crust * Basaltic eruption * Accumulation of lava - ridge-> PlatePlate MOR *New Oceanic crust **Divergent limb - expansion of ocean crust. Oceanic ridges are underwater mountain ranges that contain a rift down their center where magma seeps up, forming new oceanic crust.

  11. PaleoMagnetism is the study of the record of the Earth's magnetic field in rocks, sediment, or archeological materials. Certain minerals in rocks lock-in a record of the direction and intensity of the magnetic field when they form. O This record provides information on the past behavior of Earth's magnetic field and the past location of tectonic plates.

  12. Oceanic ridges are underwater mountain ranges that contain a rift down their center where magma seeps up, forming new oceanic crust. The rocks formed from this underwater volcanic activity were mainly basalt, which is an iron-rich, volcanic rock that makes up most of the ocean floor. Basalt contains magnetic minerals and as the rock is solidifying, these minerals align themselves in the direction of the magnetic field. This basically locks in a record of which way the magnetic field was positioned at the time that part of the ocean floor was created. Scientists took a look at the ocean floor going out away from oceanic ridges, they found magnetic stripes that were flipped so that one stripe would be normal polarity and the next reversed. Reason: these oceanic ridges were actually boundaries with tectonic plates pulling apart. This movement of the plates allowed the magma to rise up and harden into new rock. As the new rock was formed near the ridge, older rock, which formed millions of years ago when the magnetic field was reversed, got pushed farther away, resulting in this magnetic striping.

  13. Location of rocks Example Property Mantle Olivine Highly fluid; Heaviest BasaltFluid; Heavy Andesite Less mobile; Lighter Granite Least mobile; Lightest Oceanic crust Continental crust Continental crust

  14. Divergent Plate Boundary Continental crust Oceanic crust - MOR Divo Cont Rilting A Upwarping New rock added to eachside of the mid-ocean ridge Continental Crust Mogma B. Rift valley ormed C. inear Sea Mid ocean Ridge Molten material Oceanic crust Oceanic Crust

  15. Phases of Divergent continental crust Rift valley Basalt oruptions Continental- crust Mantle Rift valley Seawat River Fault -.. .. blocks Continental shelf Rift valley Sea level


  17. IRAQ IRAN Prelims 2000 Which one of the following lakes form an international boundary between Tanzania and Uganda? a) Chad b) Malawi c) Victoria d) Zambezi Cairo LIBYA | EGYPT SAUDI A RA BIA CHAD SUDA/N ERITREA YEMEN Khartoum Grand Addis Ababa SOUTHMillennium Dam SUDAN) c. A. RN ETHIOPIA. UGANDA KENYA RWANDA BURUNDI INDIAN OCEAN 1,000 km ak Victoria TANZANIA

  18. Ocean-Ocean Convergence Oceanic-Oceanic Boundary crust 100 km 200 km O-O convergence : Heavier Oceanic plate will subduct under the lighter one and will melt. Melted basaltic rocks transforms into Andesitic(which is lighter than mantel elements(olivine) and crustal elements(basalt)) and so it will move upwards and will accumulate and form island chains(Volcanic Island Arcs)-> Andesitic Volcanism

  19. O F Chait n Peru-Chile Trench and subduction Zone Pampas Andes Mountains (folded up) Aleutian trench Kurile trench e- Japan trench Izu Bonin trench South Atlantic Ocean-B Ryukyy trench Pacific Puerto Rico trench A Pacific Ocean Philippine emch Marianes trench Ocean widk America Nazca PlateBatholiths Batholths South American Plate form in interior Bougainville trench -Equaton trench Java (Sunda trench Peru-Chile trench Tonga trench Calbuco Volcano Convection Currents Drive the plates TOGETHER Mantle Why are the world's fold mountain systems located along the margins of continents? Bring out the association between global distribution of fold -mountains and earthquakes and volcanoes (10) Mains2014

  20. C-C convergence Continental-Continental Boundary Diverging limbs on Convection Cell C-C conversion. Both are Continental plates so no one will subduct. Continental plates ka subduction nahi hota Contnental O If there is intense collision bcz of the 100 ln descending limb of the convection cell then One plate will climb over other plate but the plate jo niche hai wo kabhi subduct nahi hogi. Ab jab subduct nahi hogi toh melt nahi hogi and so NO Volcanism No Volcanic activity when C-C convergence. Oceanio plae 200 Volcanic mountain ranges of Continents On the margin O Sediments, soils, rocks whatever there in Non volcanic ranges like Himalaya on the b/w of Continents. on the convergence boundary, will be crushed and will rise and will form fold mountains. Eg. Himalayan mountains, Alps.

  21. Ocean ndia india

  22. Importance of mountain building process Understanding of the origin and evolution of earth's crust. At the time of the formation of the earth crust, first basaltic crust of ocean - breaking and melting - a lighter continental crust developed Collide with one another a larger land mass. The joints - fold-mountains.

  23. Fault-block mountains Block mountains Due to forces within interior of the earth graben horst.Uplifted part horst .Depressed part- Grabben Horst->block mountains . Grabben > rift valley HORST AND GRABEN

  24. Mediserr ranean Sea Tibesti a Nubiarn Niger Guit of Hi Congo Co n itoriaIndian Ocean of Lake Tanganyik A t la nti Lake Malaw Plateau O c e a n Kalahari

  25. Me ORU MTS ENS Gan 0 Plain ngeS rahmaputr Narmada E Deccan odi Mahanao Arabian Sea Gulfof


  27. Basaltic eruption Andesitic eruption JOccur at mid-oceanic Volcanic arcs, volcanic mountains ridge and hot spot volcanism Basalt highly fluid- mobile JAndesite - less fluid less mobile Solidifies at short distance- intense pressure develop inside explosive Spread across easily Quite eruption

  28. Hot Spring Water reach deep enough heated by interior Locate any part of the world

  29. Difference between geyser and HotSpring geyser *Geyser - Groundwater heated by hot spring shallow magma source *Hot spring - g/w heated by either magma source or heated rocks Geyser chamber in interior + pressure>comes out like fountain steam groundwater porou roc superheated water *Hot-spring - quite porous rock eat magma

  30. Geyser Hot spring Found anywhere u Geysers are rare O Hot water dissolved with They gets different colors silica accumulated on surface - gives different colours from heat-loving bacteria, like cyanobacteria Medicinal values J USA, Yellowstone park Can be helpful in harness geo-thermal energy