CATEGORY 1: SHAKE, RATTLE & ROLL (Earthquakes)
This is the point on Earth's surface directly above where an earthquake's fault slip occurs.
Epicenter
In a normal fault, the hanging wall moves in this direction relative to the footwall.
Down
This principle states that "the present is the key to the past" — processes happening today also happened in the geologic past. Bonus: who proposed it?
Uniformitarianism, proposed by James Hutton
This soft, brown, low-grade coal is the second stage of coal formation, right after peat.
Lignite
Metamorphic rocks form from a pre-existing rock called this
Protolith
P-waves and S-waves both travel through Earth's interior, but only one of them can travel through liquids. Which one?
P-waves
This type of stress squeezes rocks and is most associated with reverse faults and folds. (Think: two continents colliding.)
Compression (or compressive stress)
In an undeformed sequence of sedimentary rocks, this principle tells us that the bottom layer is oldest and the top layer is youngest.
Principle of Superposition
Open pore space within a sedimentary rock is called this. The ease with which fluid flows through those connected pores is called this.
Porosity (open pore space) and Permeability (fluid flow)
The planar fabric created when platy minerals (like micas) align under directed stress is called this.
Foliation
The Modified Mercalli scale measures this aspect of an earthquake, while the Richter scale measures this other aspect.
Intensity (Mercalli) and Magnitude (Richter)
An upward-arching fold where the oldest rocks are in the center is called this. Its downward-arching cousin, where the youngest rocks are in the center, is called this.
Anticline (up-arch) and Syncline (down-arch)
A dark igneous dike cuts across several sedimentary layers. Which is younger — the dike or the sedimentary layers? And which principle tells you that?
The dike is younger, by the Principle of Cross-Cutting Relations
Why is wood NOT considered a fossil fuel, even though it's organic and burns to release energy?
Fossil fuels require millions of years of heat and pressure to form from ancient organisms. Wood is recently grown plant material — it's a biofuel, not a fossil fuel.
The protolith of marble is this. The protolith of quartzite is this.
Limestone (or dolostone) → Marble; Sandstone → Quartzite
A magnitude 7.0 earthquake produces how many times more ground motion than a magnitude 5.0 earthquake?
100 times (each whole number = 10x ground motion, so 10 × 10 = 100)
The San Andreas Fault is famous for this type of motion, where blocks slide past each other horizontally. What stress causes it?
Strike-slip motion, caused by shear stress
This is a gap in the rock record caused by erosion or non-deposition. Name the term, and name the specific type that occurs when tilted older rocks are overlain by horizontal younger rocks.
Unconformity (general term); Angular unconformity (the tilted-then-horizontal type)
Name the five essential ingredients required for a working petroleum system.
Source rock, migration pathway, reservoir rock, seal (cap rock), and trap
Arrange these foliated metamorphic rocks from lowest to highest grade: Schist, Gneiss, Slate, Phyllite.
Slate → Phyllite → Schist → Gneiss
During an earthquake, water-saturated soil can suddenly lose strength and behave like a liquid, causing buildings to sink or tilt. Name this phenomenon and the type of ground most vulnerable to it.
Liquefaction, occurring in loose, water-saturated soils (like sandy or silty ground near coasts/rivers)
You're standing in a deformed mountain range. Near the surface, rocks are cracked and faulted. Deep below, rocks are folded smoothly. Name the two types of deformation, and explain why depth determines which one happens.
Brittle deformation (near surface) and Ductile deformation (deeper). Deeper rocks experience higher temperature and pressure, which lets them flow and bend instead of breaking.
A radioactive isotope has a half-life of 1 million years. After 3 million years, what fraction of the original parent atoms remain?
One-eighth (1/8) — after each half-life, half remains, so 1 → 1/2 → 1/4 → 1/8
Hydrothermal deposits, placer deposits, and banded iron formations are all types of ore deposits — but they form in very different ways. Briefly explain how each forms.
Andalusite, Kyanite, and Sillimanite all have the same chemical formula (Al₂SiO₅), yet form under different conditions. What's the term for minerals like this, and which one indicates HIGH PRESSURE?
Polymorphs; Kyanite indicates high pressure (deep burial)