Geologic Time
This is the estimated age of Earth, determined through radiometric dating of rocks and meteorites.
What is 4.6 billion years old?
These instruments record ground motion using a weighted pen on a spring tracing movement of the frame.
What is a seismograph?
This geologic structure is a fracture or break in the Earth's crust along which movement has occurred.
What is a fault?
These geologic agents transport water and sediment from the mountains to the ocean.
What is a river?
What is infiltration?
There are only four of these geological times, and they are the broadest category of them.
What is an eon?
This is the initial point of rupture on a fault plane.
What is the hypocenter/focus?
These geologic structures are bendings or curvatures in rock layers that result from tectonic compression or stress.
What is a fold?
This terrain is a generally flat area of land next to a river, or stream, that stretches from the banks of the river to the edges the valley
What is a floodplain?
The majority of freshwater, 68.7%, are stored in these geologic structures.
What are glaciers and ice caps?
This geologic principle explains how a rock intruding another (host) rock is older than the rock it's intruding.
What is the principle of inclusions?
These types of seismic waves produce horizontal ground shaking and are the most destructive.
What are L waves?
This type of fold looks like a step and forms as faults grow beneath flat-lying sedimentary layers.
What is a monocline?
This stream load is coarser and denser than others and it remains on the bed of the stream most of the time.
What is the bed load?
This term refers to landscapes and hydrologic features created by dissolving of limestone.
What is karst?
This qualitative method of gathering numerical data can date rocks with a specific number of years.
What is absolute age dating?
These are waves generated by earthquakes in lakes.
What are seiches?
These types of faults occur when the hanging wall moves up relative to the footwall.
What is a reverse fault?
This channel type contains both erosional and depositional processes, these being a cut bank (erosional) and a point bar (depositional).
What is a meandering channel?
This rock unit is where thick deposits overly aquifer and confine it to the Earth's surface or other rocks.
What is a confined aquifer?
These rocks are located in northern Canada, and they are believed to be the oldest rocks on Earth at around 4 billion years old.
What are the Acasta Gneiss?
This scale depicts the absolute size of earthquakes and is the most common method today.
What is the moment magnitude scale?
This complex fold has both limbs dipping in the same direction but at different angles, often due to intense compression and resulting in a steep or nearly overturned structure.
What is an overturned fold?
This term is the elevation of the stream, lake, basin, or ocean into which a river flows, and erosion cannot proceed below this point.
What is the base level?
When water drops flow down a sloped ceiling before dripping to the floor, calcite can build up in a line, forming this type of speleothem.
What is a drapery?