LITHOSPHERE deposition GLACIATION LANDFORMS OF GLACIAL DEPOSITION Materials

LITHOSPHERE deposition GLACIATION LANDFORMS OF GLACIAL DEPOSITION Materials carried by the glaciers are deposited in two main ways; v. Glacial Deposits (unsorted) and v. Fluvio-glacial deposits (sorted) 1

LITHOSPHERE deposition GLACIATION Ø Moraine is the waste material worn away and collected by the ice. ØIt is angular in shape. ØGlacial deposits are poorly sorted, ie all different sizes and rock types are mixed together. 2

LITHOSPHERE deposition GLACIATION See the moraine on the glacier surface. 3

LITHOSPHERE deposition GLACIATION TYPES OF MORAINE Lateral moraine is found on the sides of the glacier. Scree, from frost shattering, is an important source. Ground moraine is found at the base (bottom) of the ice. It is also called till or boulder clay. Supra-glacial Englacial moraine is found inside the ice itself. Medial moraine is found down the middle of the glacial surface and occurs when the inner lateral moraines of two glaciers join. Terminal moraine is found in front of the snout of the glacier if it is stationary. It represents the maximum advance of the ice. 4

LITHOSPHERE deposition GLACIATION 17 5

LITHOSPHERE Terminal moraine deposition GLACIATION Snout of glacier 6

LITHOSPHERE ERRATICS They were carried by the ice-sheet, sometimes for hundreds of kilometres and then deposited. deposition GLACIATION Erratics are large rocks that are completely different from the type of rocks on which they rest 7

LITHOSPHERE deposition GLACIATION Erratics like this are often found on the valley floor. 8

LITHOSPHERE deposition GLACIATION ESKER Glacial streams are found under the ice. They are loaded with debris (sand gravel) carried by the meltwater. As the ice retreats, the river deposits load. The built-up river bed is called an Esker. This river has all but dried up! 9

LITHOSPHERE deposition GLACIATION An esker is a steep-sided, long, winding ridge, made up of gravel and sand. Most are tree-covered. 10

LITHOSPHERE DRUMLIN deposition GLACIATION Side view Drumlins are smooth, rounded mounds of ground moraine. The steep (stoss) side faces the direction the ice Moved from. Drumlins often occur in swarms or groups on the valley floor. Plan view 11

LITHOSPHERE deposition GLACIATION Here is a drumlin outside Buchlyvie. Can you work out the ice direction? 12

LITHOSPHERE deposition GLACIATION Meltwater streams bringing outwash to be distributed across an outwash plain. Note the braiding of the stream channels. 13

LITHOSPHERE deposition GLACIATION A KETTLEHOLE LAKE LOCH MORLICH LAKE OF MENTEITH depression formed when ice melts depression filled with water to form kettle lake 14

LITHOSPHERE deposition GLACIATION What is a kame terrace? GLACIER Once the ice has melted, the debris has been lowered to the valley floor and created a terrace with a steep side and flattish top. During the end stages of glaciation, a lake gathers at each side of the ice, filling with moraine. Kame terraces 15

LITHOSPHERE deposition GLACIATION This slide shows a set of kame terraces. 16