Lab 8 – Groundwater and Glaciers

Groundwater Definitions• Water Table• Zone of aeration

(Undersaturated zone/vadose zone)

• Zone of saturation (Saturated zone/phreatic zone)

• Flow lines• Aquifers• Water table contour

lines – indicate depth to water table, like a topo map

Aquifers

• Types of Aquifers– Confined– Unconfined

Wells/Cones of Depression

Wells/Cones of Depression

Groundwater Contamination

• Maybe be from large area or a point source

• Hard to trace path (unknown karst features, lithologies, etc.)– May end up in unexpected location

• May have extremely long residence time

Karst

• Karst – distinctive topography that indicates dissolution of underlying rock (usually LS)– Sinkholes– Solution valleys (linear sinkhole)– Springs– Disappearing streams

Glacial Environments

• Glaciers – ice masses formed from the accumulation of snow– Move down slope due

to weight– Transport sediment – May advance or

retreat depending on climatic conditions

Glacial Environments

Glacial Deposits

• Drift – deposits left behind after a glacier melts– Till – unstratified drift

(no water transport)– Stratified drift (melt

water transport)

Types of Glaciers• Cirque glaciers – small, semicircular to

triangular glaciers that form on the sides of mountains.

Types of Glaciers

• Valley glaciers – long glaciers that flow down stream valleys in the mountains.

• Piedmont glaciers – mergers of two or more valley glaciers at the foot of a mountain range.

Types of Glaciers• Ice sheets – vast

ice mounds that cover large portions of a continent (i.e., Greenland or Antarctica).