Erosional glacier landforms; ppt.pptx

Includes all erosional landforms such as cirque, arete, horns, fjord, hanging valley, roche moutonnèe, crag and tail

1. DR. HARI SINGH GOUR VISHWAVIDYALAYA, (A CENTRAL UNIVERSITY), SAGAR M.P. DEPARTMENT OF APPLIED GEOLOGY PRESENTATION ON GLACIAL EROSION PROCESSES AND LANDFORMS GUIDED BY: PRESENTED BY: PROF. PRADEEP KUMAR KATHAL SHUBHRA VERMA M.TECH 1 ST SEM REG. NO Y21251045

2. CONTENTS INTRODUCTION FORMATION OF GLACIERS GLACIAL MOVEMENT TYPES OF GLACIAL FLOW GLACIAL EROSIONAL PROCESSES GLACIAL EROSIONAL LANDFORMS REFERENCES

3. INTRODUCTION A glacier is a body of ice, consisting mainly of recrystallized snow, flowing on a land surface (Flint and Longwell, 1961).” Glacier are formed over many years from packed snow in areas where snow accumulation exceeds melting and sublimation. A glacier is always moving, but when its forward edge melts faster than the ice behind it advances, the glacier shrinks backward and this line is called “ snow line” . https://commons.wikimedia.org/wiki/File:Glacial_ice_formation_LMB.png http://go-11.blogspot.com/2011/12/altitude-latitude-snow-line-and-tree.html

4. GLACIAL MOVEMENT A glacier moves as a solid rather than as a liquid. The center of a glacier moves more rapidly than the sides and the surface more rapidly than the bottom, because the sides and bottom are held back by friction. The rate of flow depends largely on: The volume of ice in movement, the slope of the ground over which it is moving. The slope of the upper surface of the ice, The amount of water the ice contains, The amount of debris it carries, The temperature, and The friction it encounters.

5. TYPES OF GLACIAL FLOWS https://www.antarcticglaciers.org/glacier-processes/glacier-flow-2/glacier-flow/ http://www.soest.hawaii.edu/GG/FACULTY/POPP/Nov09_Ch_18.pdf

6. GLACIAL EROSIONAL PROCESSES https://courses.lumenlearning.com/earthscience/chapter/glacial-erosion-and-deposition/

7. GLACIAL EROSIONAL LANDFORMS Cirque - Cirques are concave, circular basins carved by the base of a glacier as it erodes the landscape.  Arete - Two adjacent cirques make up an arete. Horn - A peak formed where three or more aretes meet. Glacial trough- L ong, U-shaped valleys that were carved out by glaciers that have since receded or disappeared. Hanging Valley-  A tributary to a main valley which has been deeply scoured by glacial ice, leaving the tributary valley “hanging” above the main valley. https://www.pmfias.com/glacial-landforms-erosional-depositional-cirque-arete-fjord-esker-drumlin-moraine/

8. Col - It is a depression formed along the arete at a place where the headwalls of two opposed cirques intersect each other Truncated Spurs- The sharp and cute bends which occur along the course of stream-valleys are straightened up by glacial abrasion and in the process, it cuts projecting spurs producing blunt triangular facets, known as truncated-spars or facetted-spurs. Glacial boulders - The rock fragments entrapped in the glacial ice, get abraded, rounded and their surface polished and striated during the glacier movement. Glacial Scars - These are small-scale erosional features produced by the abrasive action of the glacier. https://mammothmemory.net/geography/geography-vocabulary/glacial-landscapes/truncated-spur.html

9. Roches Moutonnée- When a little hill of rock or small elevation is encountered on the way of the glacier, it is not usually worn away completed. The side facing the direction of glacier movement becomes gentle, smooth and striated, while the opposite side remains, rough and steep. Fjords - These are deep glacial troughs which have been eroded below sea-level or are submerged to a depth below sea-level. https://www.antarcticglaciers.org/glacial-geology/glacial-landforms/glacial-erosional-landforms/roches-moutonnees/ https://alchetron.com/Roche-moutonnée http://asapeducate.weebly.com/earth-science-terms/fjord http://asapeducate.weebly.com/earth-science-terms/fjord

10. Crag and tail - When very hard rocks like igneous bodies or volcanic plugs are encountered on the path of the moving ice sheet, they stand as pillars and resist the flow of the ice and retard its erosive action on the rocks behind the obstructions. https://www.coolgeography.co.uk/A-level/AQA/Year%2012/Cold%20environs/Glacial%20Landforms/Landforms.htm https://www.examrace.com/Study-Material/Geography/Goh-Cheng-Leong/Goh-Cheng-Leong-Chapter-6-YouTube-Lecture-Handouts.html

11. Landforms during preglacial period Landforms during glacial period https://www.facebook.com/GeoFeatures/photos/the-evolution-of-some-alpine-glacial-landforms-a-a-landscape-before-an-ice-age-b/938807269884361/ https://www.facebook.com/GeoFeatures/photos/the-evolution-of-some-alpine-glacial-landforms-a-a-landscape-before-an-ice-age-b/938807269884361/

12. Landforms during preglacial period https://www.facebook.com/GeoFeatures/photos/the-evolution-of-some-alpine-glacial-landforms-a-a-landscape-before-an-ice-age-b/938807269884361/

13. REFERENCES BOOKS Thornburry , W.D. (1958). Principles of Geomorphology, 4 th edition, John Wiley &Sons. pp- 355-373. 2. Spotila , J.A. (2013). Treatise on Geomorphology. URLs https://eartheclipse.com/geology/processes-features-glacial-erosion.html https://www.antarcticglaciers.org/glacier-processes/glacier-flow-2/glacier-flow/

14. THANK YOU