Geological and Biological Processes

These flashcards encompass key vocabulary terms and their definitions from the lecture on geological and biological processes.

Saltation

Movement of sediment particles in a series of short jumps.

Surface creep

Movement of sediment particles along the ground caused by wind.

Primary atmosphere

The Earth's initial atmosphere consisting of nitrogen, argon, hydrogen, and helium.

Secondary atmosphere

Atmosphere produced by volcanic outgassing of water vapor, nitrogen, and carbon dioxide.

Photosynthesis

Process that added oxygen to Earth's atmosphere.

Prokaryote

A single-celled organism with no distinct nucleus.

Eukaryote

A single-celled organism that has a nucleus.

Ediacaran fauna

The first abundant multicellular organisms that formed in the Ediacaran period.

Punctuated equilibrium

Theory stating that species experience long periods of stasis followed by rapid change.

Coprolite

Fossilized fecal droppings.

Cambrian period

Period during which animals with shells first evolved.

Arthropods

The first animals to inhabit land.

Trilobite

A common member of early sea life in the group that includes arthropods.

Gymnosperm

The first plants that produced seeds.

Crossopterygii

The first fish to venture onto land.

Angiosperm

Flowering plants that evolved later.

Archaeopteryx

An early bird that lived during the Mesozoic era.

Australopithecus

The first bipedal hominid.

Homo erectus

Probable first species of the human genus.

Permian extinction

The largest mass extinction event in Earth's history.

Chicxulub crater

The crater linked to the extinction of the dinosaurs.

Cretaceous extinction

The extinction event that occurred at the end of the Cretaceous period.

Flood basalts

Volcanic eruptions that may have contributed to the extinction of the dinosaurs.

Subtropical deserts

Deserts associated with low rainfall at 30°N and 30°S.

Rainshadow deserts

Deserts located on the continental side of mountain ranges.

Ventifact

A rock abraded by windblown sand.

Deflation

The removal of loose particles from the ground by wind erosion.

Desert pavement

A surface layer formed by continued wind erosion of fine material.

Angle of repose

The angle at which sliding sand comes to rest on a dune.

Arroyo

Dry river valleys present in deserts for most of the year.

Alluvial fan

A sediment deposit created when rivers drain from mountains onto flat desert floors.

Bajada

Formed when alluvial fans coalesce.

Temperate glacier

A glacier with internal ice near its melting point.

Ablation

The loss of ice from a glacier.

Internal creep

The process by which ice within a glacier moves.

Glacial striation

Scratches in bedrock produced by glaciers.

Cirque

Bowl-shaped areas where valley glaciers form.

Arete

A ridge formed between two glaciers.

Horn

A mountain peak formed between three or more glaciers.

Till

Sediment that has been glacially deposited.

Esker

Ridges formed by the deposition of sand and gravel in glacial river tunnels.

Lateral moraine

Sediments deposited along the edges of valley glaciers.

Terminal moraine

A ridge of sediment deposited at the furthest advance of a glacier.

Kettle lakes

Lakes formed in depressions made by melting blocks of ice in glacial sediment.

Periglacial

Areas located near glacial ice.

Tundra

The most common type of environment in periglacial areas.

Ice wedge

Large cracks in the ground found in cold areas.

Pattern ground

A type of terrain formed when ice wedges join together.

Paleosol

Ancient soil horizons.

Milankovitch cycles

Astronomical variations that may trigger glacial periods.

Anthropogenic

Effects produced by human activity.

Ice core

Cylinders of ice used to study past climate conditions over 200,000 years.

Peat

Plant remains in bogs that transform over time.

Coal

Material formed from peat under heat and pressure.

Oil

Substance formed from oceanic plankton.

Photovoltaic cells

Devices used to convert sunlight into energy.

Biomass energy

Energy derived from burning organic materials.

Hydrothermal deposits

Mineral deposits formed from hot water.

Placer deposits

Mineral deposits found in rivers.

Residual deposits

Mineral deposits left behind after chemical weathering.

Fractional crystallization

A process that produces magmatic mineral deposits.

Nuclear energy

The only alternative energy source that could fully replace fossil fuels.

Geothermal energy

Energy derived from the Earth's internal heat.

Hydroelectric energy

The most important source of renewable energy in Canada.

Banded iron formations

Deposits formed in the oceans due to oxygen accumulation approximately 2 billion years ago.