EMES 101: Geoscience Vocabulary Flashcards

Vocabulary flashcards covering key terms from the lecture notes on geoscience, Earth structure, solar-system formation, and the scientific method.

Geoscience

The science that studies Earth's materials, processes, history, and changes to understand the planet and its resources.

Iterative scientific process

Science progresses through repeating steps: asking questions, gathering data, analyzing, testing hypotheses, and refining explanations.

Observation

Information gained by sensing or measuring the natural world directly.

Inference

Interpretation of observations using prior knowledge.

Data

Systematic observations or measurements collected to address questions.

Model

A representation used to test or illustrate ideas (diagrams, formulas, simulations, etc.).

Hypothesis

A testable explanation or educated guess that explains observations.

Prediction

A statement about what will happen if the hypothesis is correct (If/then).

Theory

A well-supported, broad explanation that organizes facts and explains why/how phenomena occur.

Law (in science)

A concise description of a pattern or relationship that is consistently observed; a reliable rule.

Inductive reasoning

Reasoning from specific observations to general conclusions.

Deductive reasoning

Reasoning from a general principle to specific predictions or observations.

Newton’s Law of Gravitation

F = G m1 m2 / r^2; gravitational force between two masses depends on their masses and the distance between them.

Newton’s Theory of Universal Gravitation

Gravity can cause orbital motion; gravitational force explains planetary and satellite orbits.

Nebular Model of Solar System Formation

The solar system formed from a collapsing nebula; gravity gathered matter; planets formed; denser elements closer to the Sun; collisions melted material.

Big Bang Theory

The universe began ~13.8 billion years ago in a massive expansion and has been expanding since.

Seismic waves

Elastic waves produced by earthquakes used to study Earth’s interior.

S-wave

Shear seismic wave that cannot travel through liquids; moves perpendicular to the direction of travel.

P-wave

Primary seismic wave; compressional; travels through solids and liquids; fastest seismic wave.

S-wave shadow zone

Regions on Earth’s surface where S-waves are not detected due to the liquid outer core.

P-wave shadow zone

Regions where P-waves are refracted by the core, creating gaps in arrival paths.

Crust

Earth’s outermost layer; divided into continental and oceanic crust.

Continental crust

Thicker, less dense crust rich in felsic minerals and silica (granitic composition).

Oceanic crust

Thinner, more dense crust rich in mafic minerals (basaltic composition).

Mantle

Region between crust and core; mostly silicate rocks; encompasses upper and lower mantle portions.

Lithosphere

Rigid outer shell consisting of the crust and upper mantle; broken into tectonic plates.

Asthenosphere

Weak, ductile layer beneath the lithosphere that flows slowly, allowing plate movement.

Mesosphere

Lower mantle region; more rigid portion beneath the asthenosphere.

Outer core

Liquid iron-nickel layer beneath the mantle; generates Earth’s magnetic field.

Inner core

Solid iron-nickel sphere at Earth's center under extreme pressure.

Felsic

Rocks rich in silica and oxygen; light-colored; high in alkali feldspars; typical of continental crust (e.g., granite).

Mafic

Rocks lower in silica; rich in iron and magnesium; darker and denser (e.g., basalt).

Ultramafic

Rocks very high in iron and magnesium with low silica (e.g., mantle peridotite).

Igneous rock

Rocks formed by cooling and solidification of molten magma or lava.

Intrusive (plutonic)

Igneous rocks that crystallize below the surface; coarse-grained due to slow cooling.

Extrusive (volcanic)

Igneous rocks that erupt at the surface; rapid cooling yields fine grains.

Sedimentary rock

Rocks formed from deposition, compaction, and cementation of sediments.

Metamorphic rock

Rocks formed by alteration of existing rocks due to heat, pressure, or chemical fluids.

Weathering

Breakdown of rocks at the Earth's surface by physical and chemical processes.

Erosion

Removal and transport of weathered material by water, wind, or ice.

Deposition

Settlement of transported sediments in layers.

Compaction

Burial squeezing of sediments, reducing pore space.

Cementation

Minerals precipitate to bind sediment grains together.

Unconformity

A gap in the rock record representing missing time due to erosion or non-deposition.

Superposition

In undeformed sedimentary sequences, older rocks are at the bottom and younger rocks on top.

Original horizontality

Sedimentary layers were originally deposited horizontally; tilting implies deformation.

Cross-cutting relationships

A fault or intrusion is younger than the rocks it cuts.

Inclusions

Fragments of one rock included within another rock; the inclusion is older than the host.

Kepler’s laws

Describes planetary motion: orbits are elliptical, equal areas are swept in equal times, and orbital periods relate to distance.