Untitled Flashcards Set

15.15 Volcanoes

A. Volcano: opening in the earth’s crust from which molten rock pours.

   1. Magma: molten rock under the surface

   2. Lava: molten rock above the surface

   3. Volcanoes have conical shapes   ( What type of rock doesn’t take chemical weathering? ) What two countries are more likely to have earthquakes? Japan, turkey, new York, )

  4. Crater: depression at the summit

B. Volcanic ash can effect the earth’s climate

   Gas and ash are the deadliest product of a volcano

C. Factors affecting volcanic violence

    1. Viscosity: the thickness of the lava – lava contain large amount of silica will become sticky, if the lava doesn’t have silica, it will be runny

    2. Dissolved gases

    3. Increasing viscosity and gas content increases the violence of the eruption

D. notable volcanoes

   1. Mt. St. Helens, mt st helens is growing up, still an active volcano

   2. Yellowstone- a super volcano, still active, has magma beneath the surface

E. Volcanic rocks

    1. Fine grained

    2. Basalt: most common volcanic rock

    3. Pumice: Light porous igneous rock

F. Volcanic regions

  1.” Ring of fire”, Iceland, mediterranean, and East Africa  

  2. 530 Active volcanoes in the world today

  3. on average,50 eruptions per year

15.16 Intrusive rocks- igneous rock

A. Plutons: bodies of solidified magma

   1. cooled slowly- coarse grained rock

   2. coarse grained

   3. Granite- form from solidified magma

B. Evidence granite was once molten

    1. Same mineral composition and pattern, the only extension is size of crystals

    2, smooth transitions into volcanic rock

    3. Intrusions into sedimentary rock

    4. Evidence that intruded sedimentary rock experience heat

C. Types of Plutons

  1. Batholiths - Large, intrusive igneous rock bodies that form moutain ranges.

  2. laccoliths - Smaller than batholiths, intrustions that push overlyimg crust upward.

  3. Sills - Horizontal intrusions between layers

  4. Dikes - wall of igneous rocks across existing rock layers

The Rock Cycle

A. Minerals can be rearranged to form the different types of rocks.

Chapter 16 The Evolving Earth

Types of deformarion

A. Fault

  1. a fracture surface which has had motion

  2. abrupt ending and bending of sediments

B. Types of faults

  1. Normal: Rock mass slipping downward

  2. reverse: rock mass moving over another one

  3. strike slip: rock masses moving horizontally

C. Fault Scaraps: Cliffs along normal or reverse faults

D. Folding: caused by slow, continuous movement

  1. Syncline: trough fold downward

  2. anticline: arch fold upward

Moutain Building

A. Volcanic mountains

  1. Made of cone produced by volcanic deposits

  2. Mona Kea- Largest mountain of Hawaii

B. Fault Block mountains

  1. formed by reverse faults

  2. teton mountains

C. Folded Mountains

  1. folding of continental plates

  2. himalayas

Continental Drift

A. Shape of plates and sediments indicates there was a supercontinent, pangea

B. Pangea broke apart into Laurasia and Gondwana

C. These changes most likely occured during the flood.

Lithosphere and Astenosphere

A. Lithosphere

  1. Crust and outermost part of the mantle

  2. rigid layer of rock

B. Astenosphere

  1. Soft rock velow the lithosphere in the upper mantle

  2. solid rock that flows

The Ocean Floors

A. Very young (formed during the flood)

B. Features that indicate floors have spread out

  1. Mid ocean ridges

  2. trenches

  3. island arcs

  4. magnetic ridges

C. Plate Collisons

  1. oceanic-continental plate collisions

    subduction zones

  2. oceanic-oceanic plate collision

    island arcs

  3. continental-continental plate collisons

    Folded mountains