Earth Science Lecture Notes

Flashcards based on lecture notes about Earth Science topics including mapping, cosmology, the solar system, the Earth-Moon system, geologic history, plate tectonics, volcanoes, earthquakes, and tsunamis.

Topographic maps

Detailed maps showing all vertical land features including bodies of water, forests, deserts, and man-made features. Lines indicate elevation.

Contour Line

A line on a map connecting points of equal elevation; lines never cross.

Map Scale

The ratio between distances on a map and actual distances on Earth's surface.

Cartography

The study of map-making; uses images downloaded from satellites.

Latitude

Measures distance North or South of the Equator, with lines parallel to each other and values from 0-90.

Longitude

Measures distance East or West of the Prime Meridian, with curved lines that meet at the poles and values from 0-180.

Big Bang Theory

The accepted model for the universe's origin, estimating its age at 13.7 billion years.

Galaxies

Systems of stars, planets, gas, and dust; types include spiral, elliptical, and irregular.

Mercury

Small, dense, no atmosphere, extremely hot; a terrestrial planet.

Venus

Thick atmosphere, high pressure, retrograde rotation; a terrestrial planet.

Jupiter

Largest planet, many moons, strong bands of gas; a Jovian planet.

Geocentric

Earth at the center; an outdated solar system model.

Heliocentric

Sun at the center; the currently accepted solar system model.

Meteoroid

Small space rock.

Meteor

Meteoroid burning up in Earth's atmosphere.

Meteorite

Meteoroid that survives atmospheric entry and hits the Earth.

Nuclear Fusion

The process in stars where lighter elements fuse to form heavier elements, releasing energy.

Oblate Spheroid

Slightly flat at the poles and bulging in the middle.

Revolution

A body traveling around another object.

Rotation

A body turning on its imaginary axis.

Solstices

The two calendar dates when the sun appears to stop getting higher or lower in the sky at noon; sol means sun, and stice means to stop.

Equinoxes

The two calendar days in a year when day and night hours are equal; equi means equal, and nox means night.

Insolation

Incoming solar radiation.

Eclipse

To hide or cover.

Tides

Daily rise and fall of sea level along the coast.

Spring Tides

Highest high, lowest low, occurs during full and new moon, compounded gravitational pull.

Neap Tides

Highs and lows even out, occurs during 1st and 3rd quarter.

Strand Lines

Ocean debris deposited on the beach, marks highest tide level.

Highlands

Mountain regions with many craters.

Maria

Flat regions of cooled lava, dark in color.

Rilles

Meandering valley-like crack.

Waxing

Amount of the illuminated side seen increases daily, new to full moon.

Waning

Amount of the illuminated side seen decreases daily, full to new moon.

Umbra

Darkest inner part of a shadow.

Penumbra

Lighter outer part of a shadow.

Geologic History

A record of Earth's history from its origin 4.6 billion years ago to the present.

Differentiation

The process that separated heavy Earth material to form inner and outer core from lighter materials.

Uniformitarianism

The process occurring today have been occurring since Earth formed.

Relative Age Dating

Process of placing events and rock layers in sequence.

Inclusions

Particles of an older, weathered rock found in younger rock.

Fossils

Remains of once living.

Index Fossils

Fossils with widespread distribution and common for a relatively short period of time.

Miller and Urey Model

Explains how life could have originated from inorganic materials, simulated Precambrian conditions.

Stromatolites

Thick mat-like colonies of cyanobacteria, ancient single-celled organisms which thrive in warm shallow seas worldwide.

Absolute Age Dating

Method to determine actual age of a rock or a fossil using the chemical analysis.

Half-life

Amount of time required for ½ of the original quantity of a sample to decay.

Plate Tectonics

Revision of Wegener's continental drift theory, explains movement of tectonic plates on Earth's surface.

Continental Drift

Earth's continents once joined together as a single landmass broke into smaller masses.

Sonar

Sound Navigation Ranging, using sound waves and return echoes to 'see' underwater.

Seafloor Spreading

States new, hot magma breaks through the crust at MOR to create rock, cold, and old crust is pushed outward and is then melted and recycled at trenches.

Volcano

A mountain which has formed around an opening in earth's crust which releases lava from earth's interior.

Fissure Vents

Opening in earth's crust which allows magma to flow onto the surface.

Magma Chamber

A reservoir below Earth's surface that contains magma.

Crater

Bowl-shaped depression around a vent, usually 1 km > diameter.

Caldera

Very large crater, up to 50km, often forms when summit side collapse into magma chamber.

Magma

Molten and partially molten rock beneath surface.

Lava

Magma on surface, mixes with atmospheric gasses and surface materials.

Tephra

Rock fragments ejected from volcanic eruption.

Pahoehoe

Thicker, pasty lava with smooth, billowy, ropy texture; tends to form when lava discharge rate is low.

A'a

Lava with rough, jagged, clinkey texture; tends to form when lava discharge rate is high.

Shield Volcano

Mountain with broad, gentle sloping, sides nearly circular; formed by layer after layer of basaltic lava accumulating during non-explosive eruptions

Cinder Cone Volcano

Mountain with steep sides less than 500m high; formed when volcanic material is ejected high into the air and falls back to earth piling up around the vent.

Fissure Vent Volcano

Linear volcanic vent through which lava erupts; usually non-explosive, and difficult to identify.

Pyroclastic Flow

Huge cloud of gas, steam, and tephra rapidly flowing down a slope from a violent eruption.

Earthquakes

Movement of tectonic plates causes earthquakes most common at plate boundaries.

Earthquakes

Natural vibration of the ground caused by sudden movement of rock along fractures and at boundaries in crustal rocks.

Stress

When forces act on an area of material and exceed the strength of the material.

Focus

Actual location within the Earth where rocks break.

Epicenter

Point on Earth's surface directly above the focus.

P Waves

Primary body waves, 1st to arrive at seismic station, cause ground to compress and expand.

S-Waves

Secondary body waves, cause ground to oscillate up and down at right angles, do not travel through liquids.

L Waves

Surface waves, cause most damage visibly.

Seismograph

Instrument that detects and records the arrival time of seismic waves.

Tsunami

A series of waves created by an underwater earthquake.