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Two Different Types of Glacial Landforms : 1) Erosional; 2) Depositional. Types of Glacial Deposits: Till – Left directly by the ice. Unsorted and unstratified. Stratified Drift – Left by glacial meltwater. Usually sorted and layered. TILL. STRATIFIED DRIFT.
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Two Different Types of Glacial Landforms: 1) Erosional; 2) Depositional
Types of Glacial Deposits: • Till – Left directly by the ice. Unsorted and unstratified. • Stratified Drift – Left by glacial meltwater. • Usually sorted and layered.
Glaciers and Climate Change Winter Landscape by Peter Brueghel, 1601 The Little Ice Age in Holland
The Pleistocene Epoch: 1.8 million to 10,000 years ago A Much Different World
Glaciers are sensitive to climate changes and respondby advancing and retreating. • Glaciers provide information about past climate. • a) Glacial deposits are evidence of a colder, past climate (Till in Dayton is an excellent example). • b) Glacial ice contains air bubbles filled with the • ancient atmosphere. We can study past climate by • analyzing the composition of the ice bubble gases. • 3) Glaciers influence climate change! Albedo is the reflectivity of the Earth’s surface. More glacial ice increases albedo and reflects solar energy back into space. So, more ice reinforces cold climate.
The Geological History of Dayton, Ohio 40 thousand year old glacial till Unconformity 450 Million year old limestones
The Geological History of Dayton, Ohio Fig. 11.6b Environments?