Glacial Erosion II:
Processes, Rates & Landforms

Housekeeping for the day

Checking aspects of theory

Clean Ice Sliding over Clean Bedrock

Ice sliding over bed bump under 150-200m of ice at Bondhusbreen, Norway

Forces on Rock Tools

Pressure field around boulder

Checking aspects of the abrasion model

Chatter marks, arcuate cracks & lunate fractures

Lunate Fractures

Striations up close

Laser profile of striation in stainless steel

Chatter marks, arcuate cracks & lunate fractures: Sliding indentors

Glaciated Landscape with Cirques and Horns

Yosemite Valley

Speed in a Glacier Cross Section

Development of a U-Shaped Valley

Erosion into Strong Homogeneous Bedrock

Erosion into a Fault

Alaska: an ideal glacier laboratory

Singular transition between major transform fault (Fairweather)
& thrusting under most massive glaciers in N.America: coincidence?

Mt. St. Elias to Sea Level

Both transitions between major transform fault (Fairweather-Denali)
& thrusting occur under most massive glaciers in N.America: coincidence?

Could rapid glacial erosion localize thrusting?

Malaspina Glacier

Massive sediment plumes reflect rapid sediment evacuation from coastal mountains to the Pacific

Holocene Sediment in Gulf of Alaska

Important to select glaciers carefully in assessing basin-wide erosion rates

But, this leads to systematic bias

Columbia Glacier, 2005

Calving glaciers: surprising relation between calving rate and ice speed

Erosion History at Tyndall Glacier, Alaska

Denudation rates

Alaska Glacier Erosion Are High
but are they representative and robust?

Needs

Seek better understanding of how glacial erosion influences orogenic processes and reflects climate variability

Glacial Buzzsaw

Torres del Paine, Patagonia

Crossing Drake Passage

We propose to examine explicitly the role of glacier dynamics in determining glacial sediment yields through a combination of techniques from glaciology and marine geology.

Patagonia & the Antarctic Peninsula:
ideal natural laboratories for our purposes

For each glacier system, we aim to