earth sci minerals, plate tectonics, volcanism

MINERALS

 naturally occurring inorganic solid material that possesses an orderly crystalline structure and a definite chemical composition

Silicates

 most common group of minerals, contain

–SO2 groups that have a tetrahedral crystal shape

Ore

– naturally occurring concentration of mineral

deposits that can be mined

ROCKS

• consolidated mixtures of mineral

Igneous

• formed from cooled magma that solidified through

crystallization

Intrusive

– large crystals formed from slow cooling of

magma below Earth’s surface (e.g. Granite)

Extrusive

– small crystals formed from quick cooling of

lava at the Earth’s surface (e.g. Basalt)

Sedimentary

▪ formed from the lithification (compaction) of sediment

Chemical sediment

– originate from soluble materials produced by chemical weathering (e.g., Limestone, Chert)

3. Metamorphic

• formed from previous rocks that were subjected to extreme pressure and heat

Metamorphism

 rocks are subjected to extreme heat and pressure

PLATE TECTONICS

attempts to explain how major landforms are formed

from the movements of Earth’s crust

Convergent Boundary

• Plates move towards each other

• Results in subduction of oceanic

lithosphere

• Associated with the formation of

volcanic arcs and the formation

of mountain ranges

• Example: Himalayas

Oceanic-Oceanic:

: one of the oceanic plates will go under the other, producing magma chambers that produce volcanic island chains, trenches

Continental-Continental:

produces compressed rocks, which form mountain ranges

Oceanic-Continental

 the oceanic plate will go under the continental plate, producing magma chambers that produce volcanoes, mountain ranges such as the Andes

Divergent Boundary

• Plates move apart from each other

• Results in upwelling of magma

• Associated with seafloor spreading

• Example: Mid-Atlantic Ridge

Transform Boundary

• Plates grind against each other

• No lithosphere is created nor destroyed

• Can be sites for earthquake

Continental Drift

hypothesis proposed by Alfred Wegener of the breaking apart of a supercontinent (Pangaea) into smaller continents, then drifting into their current positions;

Plate Tectonics

provides the mechanism for the continental drift hypothesis; proposes that the Earth is divided into a solid and liquid layer

 Lithosphere

the rigid outer layer of the Earth, consisting of the crust and the upper mantle, which is divided into tectonic plates.

 outer solid layer of the Earth, divided into segments called plates; plates move uniformly and are deformed across their boundaries

Asthenosphere

located beneath the lithosphere, allowing tectonic plates to move.

weaker inner liquid layer of the Earth

Earthquake

rapid vibration of Earth due to the release of energy from rocks that were subjected to extreme pressure; happens in faults, which are associated with plate boundaries

Paleomagnetism

evidences of the changing location of the magnetic north pole

study of magnetic rocks

1. There is a place near the Pacific Ocean where 90% of earthquakes

occur and where 75% of volcanoes are found. What place is this?

Pacific ring of fire

What folds are found at a convergent boundary?

Rocks bent into arches

fold

 is defined as a bend in a rock.

anticline,

The upward arching is called an

syncline.

The downward arching

limbs

The sides of a fold are called .

dome

is a circular or elliptical anticline in which the limbs dip away in all directions.

Basin

is a circular or elliptical syncline in which the limbs dip toward the center.

fault

is a fracture in rocks that occurs when there is too much stress.

Composite volcano

-symmetrical cones with structures of interbedded lava and pyroclastic material

-haa small vent

Cinder cone volcano

have steep slopes made up of pyroclastic material

shield volcano

broad, domed volcanoes composed of basaltic lava

mountain ranges

are formed near boundaries of major tectonic plates.

active volcano

is a volcano which erupted within historical times (within the last 600 years),

potentially inactive volcanoes

 are the type of volcanoes which are morphologically young-looking but with no historical record of eruption.

Inactive or dormant volcanoes

have no record of eruptions and their physical form is changed by weathering and erosion

Core

the center of the earth,

is a region of dense liquid material (outer core) and solid material (inner core) composed of iron and nickel.

Crust

thin outer layer of the earth

is a solid low-density layer made of rocks that is mainly composed of silicates.

Mantle

Below the crust

is a region of the earth that is made up of hot but not quite molten rock.

Moho or the Mohorovičić Discontinuity

is the boundary between the crust and the mantle and cannot be made of dense liquid.

Geothermal

What kind of power plants harnesses the energy of volcanoes?

Composite volcano

1. kilala ang Bulkang Pinatubo sa pagkakaroon nito ng magandang hugis ng cone, matarik na slope, at maliit na vent. Anong klaseng bulkan ang Pinatubo?

caldera

is formed when the vent collapses after a violent eruption.

Cinder cone volcanoes

 rarely grow larger than about 1,000 feet above their surroundings. They form a circular oval-shaped cone, with a bowl-shaped crater at the top.

Shield volcanoes

are built entirely from fluid lava flows

Convection currents

What  cause plates to move?

Lithosphere

is the outermost solid layer of the Earth. It includes:

The crust (where we live), and

The upper part of the mantle (the hard, rigid part).

Weathering

- disintegration and decomposition of rock near the surface

Mass-wasting

- transfer of rock material down a slope due to gravity

Erosion

 incorporation and transportation of material by mobile agent such as water or wind

Movement of tectonic plates

Can result in earthquakes and the formation of

volcanoes, mountains, rift valleys, trenches,

mid-oceanic ridges, and islands