Consider the following statements :1. Sedimentary rocks are crystallin...
Igneous rocks are crystalline in structure whereas Sedimentary rocks are non-crystalline in nature.
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Consider the following statements :1. Sedimentary rocks are crystallin...
Igneous rocks (primary rocks) are formed by crystallization /solidification of the molten magma.
Sedimentary rocks are formed by
weathering of igneous rocks (gives various slats and secondary clay minerals)
:
Those salts and minerals transported via Air,water,gravity.....
:
Deposition or sedimentation
so, sedimentary rocks contains fossils bot are not crystalline in naturee
Consider the following statements :1. Sedimentary rocks are crystallin...
Sedimentary rocks and igneous rocks are two different types of rocks that are formed through different processes. Let's analyze each statement to determine their correctness:
1. Sedimentary rocks are crystalline in structure whereas igneous rocks are non-crystalline in nature.
- This statement is incorrect. Sedimentary rocks are not always crystalline in structure. In fact, many sedimentary rocks have a clastic or fragmental texture, which means they are composed of various sediment particles such as sand, silt, and clay, that are cemented together. These rocks may not have a crystalline structure. On the other hand, igneous rocks can have both crystalline and non-crystalline (glassy) structures, depending on the cooling rate of molten rock material. So, this statement is not true.
2. Sedimentary rocks often contain fossils whereas igneous rocks do not contain fossils.
- This statement is correct. Sedimentary rocks are formed from the accumulation and lithification of sediments, which may include organic materials like plant remains or animal fossils. Fossils are preserved in sedimentary rocks because they are often buried and protected from weathering and erosion. In contrast, igneous rocks are formed from the solidification of molten materials and do not typically contain fossils. So, this statement is true.
3. Sedimentary rocks are classified according to their age and igneous rocks are sub-divided on the basis of mineral composition.
- This statement is incorrect. Sedimentary rocks are classified based on their composition, texture, and the environment in which they were formed. They can be further categorized based on grain size, sorting, and the presence of specific minerals. Age is not the primary criterion for classifying sedimentary rocks. On the other hand, igneous rocks are classified based on their mineral composition, texture, and the cooling history of the molten material. Mineral composition is an important factor in distinguishing different types of igneous rocks. So, this statement is not true.
In conclusion, the correct statements are:
- Statement 2: Sedimentary rocks often contain fossils whereas igneous rocks do not contain fossils.
- Statement 3: Sedimentary rocks are classified according to their age and igneous rocks are sub-divided on the basis of mineral composition.
Therefore, the correct answer is option 'C' (2 and 3).
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