INDI OCEAN Google Maps AUSTRALIA DIAMANTINA TRENCH Perth 1,460 MILES
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
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
Convection cells = force behind drifting of continents Ridge Push Lithosphere Mantle Convection Cell Convection Cell Outer core Inner core
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
Rifting makes oceans widen Continental plate 20mm/year Rising material
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.
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.
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.
TH AMER PLATE EURASIAN PLATE EURASIAN PLATE JUAN DE PLATE CARIBBEAN PHILIPPINE PLATE /PLATE ARABIAN PLATE cocos PLATE PLATE EGUATOR AFRICAN TE PACIFIC PLATE NAZCA PLATE AUSTRALI PLAT SOUTH AMERICAN PLATE AUST PLATE OTIA PLATE ANTARCTIC PLATE
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
Divergent Plate Boundary Ascending limb of convection current - can be below Ocean or Continent. PlatePlate If Below ocean -> formation of MOR If Below continent ->rift valley, nascent sea
Phases of Divergent continental crust Rift valley Basalt oruptions Continental- crust Mantle Rift valley Seawat River Fault -.. .. blocks Continental shelf Rift valley Sea level
Mediterranean Sea EGYPT SUDAN SOUTH SUDAN ETHIOPIA UGANDA Lake Victoria INDIAN OCEAN
hungking Ryukyu 4 Islands Henchow BONIN INDI CHINA ISLANDS ap. iwan Hano URM Br) Hong Kong (Br) FRENCEH unan IN CIINA SOUTH PACIFIC Sharri Thailand CHINA Lu PHILIPPINE OCEAN nruhn SEA Manilli Bangkok ISLANDS , ADAMAN SEA Bay Saigo GUL Palawar SIAM Mindanao o Caroline Palau Islands ota Bharu Jap.) (Br) dakan Mekgn MALAYA Lumpur Farakan (Br) Man Singapore Halmahera Sumatra endari Amb JAVA SEA Maka Oosthaten. Ne INDIAN Vet BANDA SEA va e FLORES SEA OCEAN aba limor ARAFURA SEA Christmas Island OKubang TIMOR SEA
made of Continental volcanic arc Oceanic Crust Basalt. Trench Continental Crust Granite. Oceanic crust O So Oceanic crust is heavier and so it subducts under Continental Crust. And then it melts and then conversion of these Basalt rocks into Andesite and then it comes out via a explosive volcanoes. A volcanic mountain Chain will be formed on the Margin of that continental crust. ducting oceanic lit Continental lithosphere anic lithosphere t Metting Asthenosphere
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
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ARCTIC OCEAN Mountain Ranges of the World ASIA NORTH AMERICA EUROPE PACTFIC ATLANTIC 1. Arts OCEAN s OCEAN AFRICA PACIFTC OCEAN SOUTH AMERICA INDIAN OCEAN AUSTRALIA Great viding ATLANTIC OCEAN 1,000 2 ANTARCTICA
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
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ARCTIC OCEAN ATLANTIC OCEANv ASIA A EUROPE Black Sea Caspian Sea Mediterranean Sea
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Kaliosh TIBETA CHINA PLATEAU ung Tsang angtse BHUTAN rahmo BANGLADE BURMA (MYANMAR) VIETNAM BAY OF AOS BENGAL SOUTH CHINA SEA THAILAND VERS CAMBODIA TIBET Michoel Buckley ANDAMAN SEA A N
Intrusive Landforms *Intrusion of Magma in sedimentary rocks Sills (Horizontal) * Dyke (Vertical) Laccolith-magma which could not come out &Lopolith - saucer-shaped Phacolith-shape like waves Batholith-intrusive granitic rock
Shield/ dome Cinder Highly fluid ss fluid /highly F Silent flovw Gentle slope Steep slope Composite Fluid viscous viscous Violent eruption Multiple and violent eruption Highest volcanoes Small volcanoes Small volcanoes Large volcanoes
Limitations of geo-thermal energy *Difficult to locate a good source of geothermal reservoir with current technology * Difficult to dig a deep well with hard and hot bedrock Harmful gases can escape from the earth interior while exploration - GHG gases and dissolved toxic elements.
How a tsunami occurs An earthquake- rocks the ocean floor 2 Displaces volume of water, pushing it up 3 Sets off an oscillation, which develops underwater at great speed 4Sea water is sucked back from the shore Waves get bigger as water gets shallower
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