Sedimentary Rock
Sedimentary rocks are one of the three main rock types while the others are the igneous rocks and the metamorphic rocks. Sedimentary rocks are formed by the deposition and consolidation of the mineral and organic material and from the precipitation of minerals from precipitation of minerals from the solution. The process that forms the sedimentary rocks occurs at the surface of the earth and within the bodies of water. The rocks that are formed by the sediments cover the 75 to 85 % of the earth crust.
It includes common types such as the limestone, chalk, dolostone, sandstone and some type of breccias and shale. Sedimentary rocks are formed by the source of the segments and are produces by one or more of:
- Clastic rock formed from the fragments of which are broken of from the parent rock by either weathering or erosion. Weathering is formed in situ and erosion is caused by water, ice or wind. This is followed by the transfer of the sediments to the place of deposition.
- The biogenic activities.
- And precipitation from solution.
I do feel that you should know about the weathering as well as the erosion in detail. I would like to put forward each of the one by one. They are as follows:
1. Weathering
Weathering is the decomposition of the earth rocks, soil and their minerals through the direct contacts of the planet atmosphere. The weathering occurs is situ and is always marked by no movements and hence should not be confused with the erosion which occurs due to the movement caused by the agents like water, ice, wind and gravity.
The two important types of the weathering are the physical and chemical weathering. The physical weathering occurs due to the direct contact of the atmospheric agents like water, ice, heat and pressure.
2. Erosion
The erosion is marked by the movement. It is the movement of the solid in the natural environment. I usually occur due to the transport by ice, water and wind.
However the most parts of the earth crust is covered by the sedimentary rocks. I must say that where ever you will definitely find the sedimentary rocks.
The two type of weathering, which results into the formation of the sedimentary rocks are the mechanical weathering and the chemical weathering as I have stated above. You must really understand that the sedimentary rocks are mostly formed due to weathering.
Hence weathering is an important phenomenon which you should know in detail if you want to study sedimentary rocks in detail. In short you can divide the sedimentary rocks into two kinds of the rocks. They are the chemical sedimentary rocks and the organic sedimentary rocks.
I do feel that you will definitely find the research in sedimentary rocks to be very fruitful.