Earth 102 Final Exam

Porosity

Percentage of open spaces between grains in a rock.

Permeability

Ability of rock or soil to allow water to flow through it

zone of aeration

upper soil layers that hold both air and water

zone of saturation

The lower zone where water accumilates between small rock particles.

water table

The upper level of the saturated zone of groundwater

discharge

the quantity of water in a stream that passes a given point in a period of time

Aquifers

Subterranean, porous, water-holding rocks that provide millions of wells with steady flows of water.

Aquiclude

A body of rock that will absorb water slowly, but will not transmit it fast enough to supply a well.

hydraulic gradient

the slope of the water table

confined aquifer

A groundwater storage area trapped between two impermeable layers of rock.

cone of depression

lowering of the water table around a pumping well

artesian system

a confined aquifer system in which ground water can rise above its aquifer under its own pressure

conditions necessary to form an artesian system

an inclined aquifer sandwiched between impervious rock layers above and below that trap water in it

Is the water table a fixed line or does it vary

The water table level can vary in different areas and even within the same area. Fluctuations in the water table level are caused by changes in precipitation between seasons and years. During late winter and spring, when snow melts and precipitation is high, the water table rises.

salt water intrusions of aquifers occur

when storm surges or high tides overtop areas low in elevation.

Oasis

a fertile spot in a desert where water is found.

how are oasis formed

an underground aquifer or river that creates enough pressure for water to seep to the surface

where does the City of Chico get its water

Butte Basin + groundwater

How can global climate affect sea level

glaciers and ice sheets worldwide are melting and adding water to the ocean.

major coastline features

headlands, cliffs, bays, spits, salt marshes, and beaches.

emergent coastline

coastline where sea level is dropping or the land is rising

Submerging coastline

As sea levels rise, the land is covered

factors contribute to coastal retreat

Depressions have stronger winds resulting in rapid rates of recession

longshore drift

The movement of water and sediment down a beach caused by waves coming in to shore at an angle

Headlands

points of high land that stick out into a body of water

cliffs

steep rock faces, like those at the edge of the sea

Bays

bodies of water, smaller than a gulf and nearly surrounded by land.

Spits

Thin lines of sand deposited by long shore transport

Salt Marshes/Estuaries

a saltwater biome that contains non-woody emergent vegetation

beaches

deposits of sand and other fragments of rock left along the shoreline boundary

How do humans attempt to halt beach erosion?

Seawalls, revetments, bulkheads, groins and breakwaters may reduce erosion in the short-term

zone of accumulation

the area where a glacier forms

Zone of wastage (ablation)

Region in lower part of glacier where more snow/ice melts than accumulates resulting in loss of glacial ice.

Firn

A dense, icy pack of old snow

Valley glaciers

glaciers that form in valleys in high, mountainous areas

continental glaciers (ice sheets)

flow out from where the ice is thickest, are on flat ground

glacial erosional features

Cirque, U-Shaped Valleys, Glacial Striations, Arete, Trim Line, Hanging Valley

Glacial depositional features

outwash plains

eskers

kettle lakes

drumlins

kames

When did the last ice age end?

10,000 years ago

inter-glacial period

A period of warmer climate that is characterized by the retreat of glaciers

consequences of the last period of continental glaciation

Melting glacial water runs off into the ocean and sea-level worldwide will rise.

What are playas

Interior evaporite basins. Salt flats.

What occupies these arid basins in wet climate periods

plants

What occupies many of these basins now?

nothing

How do those rocks move across Racetrack Playa in Death Valley N.P.?

Ice, and wind

alluvial fans

Fan-shaped deposits of sediments dropped by streams flowing out of mountains

hazards of alluvial fans

inundation by flood water, debris flow and debris flood deposits, channel migration, deposition, and erosion.

desert varnish

A dark, rusty-brown coating of iron oxide and magnesium oxide that accumulates on the surface of the rock.

Ventifacts

rocks shaped by wind blown sediments

Why are most deserts rocky

the wind has stripped of all debris produced by meteoric degradation

Badlands

Wasteland that has been carved into unusual shapes by wind and water

Types of sand dunes

barchan, parabolic, transverse, longitudinal, star

Haboob

Desert sandstorms that form in the downdrafts of a thunderstorm.

wind transport

Usually small grains, sand sized or smaller; Sand dunes and loess deposits

water transport

Conducted in plants through root pressure, capillary action, and transpiration.