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Chapter 05
Geological Studies
Shattered debris due to frost action
Fig.4b: Glacial striations in the vicinity of Nandi
m and 5700 m respectively while climbing the Serdung Chuksum La that connects the Kailash with that of the Nandi Mountain (Figure 4). Presently, the valley glaciers on the southern slope of the Kailash Mountain are virtually absent. Instead one can see the avalanche snow that extends at the foot of the Kailash Mountain on the eastern and western valleys. It is likely that during winters a marginal increase in the snow occurs, which is insufficient for sustaining a permanent valley glacier. It can be inferred that presently influence of valley glaciers in landscape development is virtually insignificant. Frost Action: Frost action is a type of mechanical breakdown of rocks where water actually seeps into cracks in the rock. The water freezes as the temperature drops, it expands and eventually creates a wedge inside the rock, encouraging it to crack and split apart. Also known as frost shattering, this type of weathering occurs mainly in environments where temperatures frequently fluctuate above and below freezing point that is, mainly in areas proximal to glaciers (periglacial areas). This is the case around Kailash and Nandi Mountain. This action is amplified in areas where fractured or highly porous rocks are present as we have seen in the Kailash conglomerate which is not only porous but also contain vertical fractures (Figure 5). The broken rock fragments eventually rolled down the slopes due to the gravity and forms conical apron of unconsolidated debris also known as the scree or talus slopes which are quite common in the higher Himalaya. In the Kailash region, particularly around Nandi Mountain and the western flank of the Dharma King Norsang, a thick apron of frost shattered debris covering the lower part could be seen (Figure 6). In order to ascertain their source, rock samples were collected at regular intervals around the inner Kora that circles the Nandi Mountain. These broken rock fragments were dominated by conglomerate and subordinate sand stone which constitute the Nandi Mountain. Considering that the top of the Nandi Mountain (6000 m) consists of the conglomerate with
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Geological investigation of rock sculptures...
