Some important sedimentary rocks are as under; (1). Conglomerate Nature: Consolidated gravels. Colour variable. Mineral Composition: Rounded pebbles are set in a fine-grained matrix. The matrix commonly consists of sand and silt and it is cemented by silica, calcium carbonate, or iron oxide. The individual pebbles may be entirely composed of quartz or maybe rock
The composition of sedimentary rocks is of two types; chemical composition and mineral composition. The chemical composition of a substance means the aggregate chemicals that constitute that substance, while the presence of different types of minerals illustrates the mineral composition of that substance. Here we will discuss the two types of compositions separately. (1). Chemical
Sedimentary rocks constitute about 75% of the total exposed rocks on the earth’s crust. They are found in different forms/structures. The important structural features of sedimentary rocks are stratification, lamination, graded bedding, current bedding, ripple marks. Besides these, there are some minor structures such as mud cracks, rain prints, tracks of terrestrial animals, etc. These
The texture of the sedimentary rocks is studied like that of the igneous rocks. Texture means the size, shape, and arrangement of grains in a rock. The particles of the sedimentary rocks are known as the ”Sediments”. As sediments contain particles of various sizes, grain size is an important factor in the description of sedimentary
Classification of the sediments (that form the sedimentary rocks) is made on the basis of the sources of the sediments. Some of the rocks are formed from the sediments obtained from pre-existing rocks, while some are formed from the sediments sourced from the minerals precipitated from water. On the basis of the above mentioned two
Sedimentary Rocks The upper 16 km thick earth’s crust contains only 5% of the sedimentary rocks, while the percentage of the sedimentary rock in the exposed rocks is about 75%. These rocks are found chiefly as an extensive cover over the continental crust. In the subject of rock formation, sedimentary rocks and their formation is
There are two basic types of igneous rocks i.e. Intrusive Igneous rocks and Extrusive igneous rocks. Intrusive igneous rocks are those, which crystallize below the earth’s surface, and remain buried until the earth’s surface is eroded, while extruded igneous rocks are those, which erupt onto the surface, where they cool quickly to form small crystals.
Assimilation of rocks is the process of engulfing the solid or molten parts of the country rocks in the magma when it rises up towards earth's surface.
We can find the mineral composition of igneous rocks by means of studying the chemical composition of the magma from which the rock has been crystallized. Because there is a large variety of igneous rocks, thus it was originally thought an equally large variety of magma also existed. But the later research found out that
Differentiation of Magma while cooling and solidification: Magmatic differentiation means the split of magma into various parts due to the presence of different types of chemicals in it. These parts of magma on cooling and solidification produce rocks of different types. As the chemical composition of magma differs in its different parts and layers, the
