Operation of the Rock Cycle with Reference to the Geology in Hong Kong.

Only available on StudyMode
  • Download(s) : 144
  • Published : May 12, 2013
Open Document
Text Preview
Explain the operation of the rock cycle with reference to the geology in Hong Kong. To what extent are the rock types responsible for the deep weathering profile in the territory? Hong Kong is dominated by igneous rocks which granite takes up the largest proportion of 85% of the total land area. The remaining area is underlain by sedimentary rocks superficial deposits mainly in the North West area. Other than the above rock types, there still a kind of rock which covers only a small area of Hong Kong, its metamorphic rock, mainly can be found in the north-western part of the New Territories. First, let’s talk about the igneous rocks in Hong Kong. Dated back to the late Jurassic age, Hong Kong was located near to the destructive plate boundary on the south- east coast of China, generating pressure during the subduction activity and causing vulcanicity. In the destructive plate boundary, magma currents beneath earth crust converge, dragging two plates together while the heavier plate sinks and being subducted under another plate, the subducted zone will then be melt back to magma again. Pressure accumulates while the subduction of the heavier plate is occurring, crack will develop on both plates near the boundary allowing magma to seep through them onto the earth surface. Magma that rose through the cracks may soon be cooled down by the temperature of the earth surface and forming extrusive igneous rocks and building a volcano gradually at the same time. These extrusive igneous rocks can be found in western Lantau Island, the southern part of Hong Kong Island, and the central, northern and eastern parts of the Territories. Intrusive igneous rocks can also be found in both sides of the Victoria Harbour, eastern Lantau Island, Castle Peak, Tai Lam, Sha Tin and Tai Po. They are formed by exposed batholiths of the volcanoes in the Jurassic age; granite is the most abundant type of rock that can be found. Many of the igneous rocks like tuff and granite we can...
tracking img