Geology Lab Topics: Weathering, Dating, Earthquakes, Topography, Streams, Groundwater

What rocks are more susceptible to weathering?

Marble, because it is metamorphosed limestone and dissolves easily in acid.

What is the formula for weathering rate?

Weathering rate = change in thickness / time.

Which weathers faster, marble or granite?

Marble.

What is the Principle of Superposition?

Youngest layers on top, oldest on bottom.

What is the Principle of Original Horizontality?

Sedimentary layers are deposited horizontally.

What is the Principle of Cross-Cutting Relationships?

Younger features cut across older layers.

What is the Principle of Inclusions?

They are older than the rock containing them.

Why can't carbon-14 date Cambrian fossils?

Carbon-14's half-life (~5,730 yrs) is too short.

After 3 half-lives, how much parent remains?

1/8 parent, 7/8 daughter.

How does stress build on faults?

Elastic deformation builds until friction is overcome and the fault slips.

What is the recurrence interval if fault slip is 200 cm per quake and movement rate is 1.6 cm/yr?

~125 years.

If rocks offset by 400 km formed 25 million years ago, what is the slip rate?

1.6 cm/yr.

What does the Rule of V's tell you?

Streams flow downhill, out of the V's.

What do hachure marks indicate?

Depressions.

What is topographic relief?

Difference in elevation between two points.

How do you find contour interval?

Subtract two index contours and divide by number of spaces.

What is a watershed?

Area that drains all water to a common outlet.

What separates watersheds?

Drainage divides (high areas).

What is the formula for stream discharge?

Discharge = width × depth × velocity.

What is the difference between high and low gradient streams?

High = fast, steep; Low = slow, flat.

How does groundwater flow relative to contour lines?

At right angles from high to low.

What type of stream is fed by groundwater?

Gaining stream

What is the 3-point problem used for?

Drawing groundwater contour lines.

What is the density formula?

mass / volume.

What is the difference in density between oceanic and continental crust?

Oceanic is denser.

What is the difference between cleavage and fracture?

One is flat, and one is irregular.

What do sorting and rounding indicate?

Transport distance & depositional environment.

What are the three types of plate boundaries?

Divergent, convergent, transform.