Earth and Life Science: Habitable Planet and Rock Types

NUTRIENTS

Used to build and maintain organism's body function.

CARBON

Backbone of Life.

MAGNETIC FIELD

A planet requires a rapidly rotating magnetic field to protect it from flares from nearby stars and harmful radiation.

TROPOSPHERE

All weather phenomenon.

STRATOSPHERE

Ozone is located.

MESOSPHERE

Asteroids enter the atmosphere, they burn up, creating streaks of lights.

THERMOSPHERE

Layer where Aurora Borealis and satellites are revolving.

GEOSPHERE

Solid region of Earth.

CRUST

1% only with two types: Continental (70km) and Oceanic (7km).

MANTLE

82% of the Earth's volume.

LITHOSPHERE

The rigid outer part consisting of the crust and upper mantle.

ATHENOSPHERE

The upper layer of the Earth's mantle.

CORE

Made up of two divisions: Outer (2260km) and Inner (1216km).

CRYSTAL SOLID

The organized structure of a mineral.

CHEMICAL COMPOSITION

A mineral can be described by a chemical formula.

GENERALLY INORGANIC

Only a few organic substances are considered minerals; all other minerals are inorganic.

HYDROSPHERE

71% of the Earth's surface. A dynamic mass that interacts with Earth's spheres through the water cycle.

COLOR

Most minerals occur in many hues and generally cannot be distinguished by color alone.

STREAK

The color of the pulverized powder of a mineral. More consistent than color found by scraping a mineral against a porcelain plate.

LUSTER

The way a mineral's surface scatters light.

HARDNESS

The measure of a mineral's resistance to scratching. Represents the strength of bonds in the crystal lattice.

MOHS HARDNESS SCALE

Qualitative scale to measure a mineral's hardness.

SPECIFIC GRAVITY

The weight of a substance divided by the weight of an equal volume of water.

MINERALOGY

The study of minerals.

MINERAL

A homogeneous, naturally-occurring, solid, and generally inorganic substance with a definable chemical composition and an orderly internal arrangement of atoms.

CLEAVAGE

The tendency of a mineral to break along a plane of weakness in the crystal lattice.

FRACTURE

The mineral breaks in no consistent manner. Equal bond strength in all directions.

CONCHOIDAL FRACTURE

The tendency for a mineral to break along irregular scoop-shaped fractures that are not related to weaknesses in the crystal structure.

ROCK

A natural substance, a solid aggregate of one or more minerals or mineraloids.

AGENTS OF DENUDATION

The sediment was formed by weathering and erosion from the source area, and then transported to the place of deposition by water, wind, ice, mass movement or glaciers.

ROCK CYCLE

A set of processes that transform rocks from one type to another.

HABITABLE ZONE

A planet must have a certain distance from the star to achieve a temperature where water could exist in the liquid state, which also ensures that compounds like proteins and carbohydrates (in the case of carbon-based life forms) do not break down.

ATMOSPHERE

Traps heat, shields from harmful radiation and provides chemicals needed for life.

WATER

Dissolves & transports chemicals within and to and from a cell. Water is an essential ingredient for transporting nutrients and chemicals between cells.

ENERGY

Organisms use light or chemical energy to survive. Cells can run the chemical reaction with a steady input of light and chemical energy.

WEATHERING

Process of breaking down rocks physically or chemically.

IGNEOUS ROCKS

Formed through the cooling and solidification of magma or lava.

EROSION

Process of eating away rocks from their source with the help of gravity, water, wind, or organisms.

MELTING

Caused by one or more of three processes: an increase in temperature, a decrease in pressure (decompression), or a change in composition.

DEPOSITION

The settling of the sediments in an area before they are finally lithified to form sedimentary rocks.

INTRUSIVE ROCKS

Rocks formed below the surface (Plutonic).

EXTRUSIVE ROCKS

Rocks formed on the surface (Volcanic).

DIAGENESIS

A group of processes responsible for the transformation of sediments into sedimentary rocks.

COMPACTION

Soil and sediment mass losses pore space in response to the increasing weight of overlying material.

CEMENTATION

The precipitation of a binding material around minerals or grains in rocks.

RECRYSTALLIZATION

The process that alters the mineral composition and texture of the rock when subjected to high temperature and pressure within the earth.

METAMORPHIC ROCKS

Arise from the transformation of existing rock types in a process called metamorphism.

SEDIMENTARY ROCKS

Formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water.

AGENTS OF METAMORPHISM

Heat, pressure or stress due to confining pressure and differential stress during mountain building, and chemically active fluids (mainly water and other volatiles) which promote recrystallization by enhancing ion migration.

LOW-GRADE METAMORPHISM

Slight changes in the original features of the rock.

HIGH-GRADE METAMORPHISM

Substantial changes that cause the original features to be obliterated.

Metamorphic Setting

Conditions under which metamorphic rocks form.

Contact Metamorphism

Occurs when magma intrudes surrounding rock.

Regional Metamorphism

Large-scale metamorphism due to heat and pressure.

Foliated Texture

Mineral alignment perpendicular to compressional force.

Non-Foliated Texture

Contains equidimensional crystals, resembles igneous rock.

Slate

Finely grained rock from low-grade shale metamorphism.

Schist

Strongly foliated rock with platy crystal structure.

Gneiss

Banded texture with strong mineral segregation.

Marble

Metamorphosed limestone, often used in sculpture.

Quartzite

Forms from the metamorphism of quartz sandstone.

Continental Drift Theory

Explains how continents shift positions over time.

Paleontological Evidence

Study of ancient life through fossils.

Alfred Wegener

Proposed the Continental Drift Theory in 1912.

Seafloor Spreading

Occurs at mid-ocean ridges as plates diverge.

Tension Stress

Occurs when plates pull apart, stretching rock.

Compression Stress

Occurs when plates push together, squeezing rock.

Shear Stress

Pushes rock masses in opposite sideways directions.

Normal Fault

Hanging wall moves downward relative to footwall.

Reverse Fault

Hanging wall moves upward due to compression.

Strike-Slip Fault

Walls move sideways along the fault line.

Plate Tectonics

Earth's crust divided into moving tectonic plates.

Divergent Boundary

Plates pull apart, forming mid-ocean ridges.

Convergent Boundary

Plates collide, forming trenches and mountains.

Subduction Zone

Denser oceanic plate sinks beneath continental plate.