ESSC 101 Exam 2 Bruce Sherman

Batholith

one or more contiguous plutons. Multiple magmas emplaced over long period of time.

List of Physical Properties of minerals

Crystal Form, Luster, Color, Streak, hardness, Cleavage, Fracture, Specific gravity

Silica Tetrahedron makeup

Crystalize from molten material. Minerals are divided by how the silica tetrahedra are arranged.

What happens in an Oceanic- Continental Plate Boundary?

Denser oceanic slab sinks into the asthenosphere. Pockets of magma develop and rise. Continental volcanic arcs form.

Plutonic

Intrusive- formed below surface

Transform faults

Join two segments of a mid- ocean ridge. Aids the movement of oceanic crustal material.

Active continental margins

Subduction zone forms. Deformation process begins.

phaneritic texture

"Coarse-grained" Mineral crystals large enough to see with the unaided eye SLOW crystallization inside crust (Like oatmeal cookies)

Aphanetic Texture

"Fine-grained" Mineral crystals too small to see without aid of microscope or hand lens. Fast crystallization at the surface. (Sugar cookie)

Tranform Boundary

Slide Past one another.

What determines the violence of an eruption?

- composition of the magma - temperature of the magma - dissolved gases in the magma

What is a Mineral?

- natural - inorganic - Solid- crystalline - have a definite chemical composition - unique set of physical properties.

Main elements in the Universe

1. Hydrogen 2. Helium (The sun takes hydrogen and crushes it into helium)

Main elements in the Entire Earth.

1. Iron 2. Oxygen 3. Silicon

What are the 3 types of Plate Boundaries?

1. Oceanic - continental 2. Oceanic - Oceanic 3. Continental- Continental

Main elements in Earth's crust

1. Oxygen 2. Silicone 3. Aluminum

What are hot spots?

Caused by rising plumes of mantle material. Volcanoes can form over them. They move.

Isostacy

Concept of a floating crust in gravitational balance

3 types of igneous intrusions

Dikes, Sills, Batholith

volcanic

Extrusive- formed at the surface

How do volcanic bombs originate?

From pyroclastic material ejected as hot lava.

Related rocks

Granite and Rhyolite Diorite and andesite Gabbro and Basalt

Cooling and Crystallizing

Magma changes to igneous rock by cooling of molton rock.

porphyritic texture

Mixed coarse and fine grained material. (Chocolate Chip Cookies)

What are the lines of evidence for plate tectonics?

Ocean drilling

Orogenesis

Processes that collectively produce a mountain belt

Continental Accretion

Small crustal fragments collide with and accrete to continental margins. (Pieces squished into continental margins)

obsidian and pumice

Two examples of volcanic glass are ____.

What happens in an Oceanic- Oceanic Plate Boundary?

Two oceanic slabs converge and one descends beneath the other. Often forms volcanoes on the ocean floor. Volcanic arcs forms as volcanoes emerge from the sea.

What are the two major gasses expelled from a volcanic eruption?

Water vapor and carbon dioxide

What happens in Continental- Continental plate boundary?

When sub-ducting plates contain continental material, two continents collide. Can produce new mountain ranges such as the Himalayas.

Continental collisions

Where two plates with continental crust converge.

What drives an eruption

how easily gases escape from magma. Viscous magma produces a more violent eruption.

Phenocrysts

large crystals

Why is viscosity important?

more viscous: difficult to flow and traps gas. Less viscous: flows easier and gas can escape.

Andean- type Mountain building

oceanic-continental crust convergence, example is Andes Mountains.

Parts of an atom

protons, neutrons, electrons

What is viscosity?

resistance to flow

Dikes and Sills

sheet of rock that formed in a fracture in a pre-existing rock body.

Two largest mineral groups

silicates and carbonates

Matrix or groundmass

small crystals

Sills

tabular sheet of igneous rock intruded between and parallel with the existing strata.

What is Bowen's reaction series?

the order in which specific minerals cool and form within melted magma, from hottest to coolest

accretionary wedge

triangular shaped structure of folded up rock.

How are magmas generated?

•Mantle plume spreads out along the boundary, causing melting of overlying lithosphere •In oceans, hot spots may form oceanic islands •On continents, mafic magma erupts as basalt •On continents, hot spots erupt explosively if composition is felsic or intermediate

Mixing

•Mixing produces a magma that has a composition intermediate between the two magmas