Jahangir

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Sedimentary rocks in Pakistan range in age from Precambrian to Miocene i.e from oldest to youngest on the geological time scale form 542 million years to latest. Luckily for geoscientists all of them are exposed in different parts of the country. Lithologically they constitute sandstone, limestone, shale and mixed lithologies of them all. These rocks are exposed all along the mountain ranges from Islamabad in north to Karachi in the south.

Igneous rocks are exposed north of Peshawar or only at Nagarparker in the southeastern corner of the country.

You better study 'Stratigraphy and historical geology of Pakistan' by Kazmi and Abbasi (2008), which will provide you a full knowledge about the rocks in Pakistan. 'Geology and tectonics of Pakistan' by Kazmi and Jan (1997) also gives details of distribution of ores and minerals in different parts of the country. Names

[de] Mergel
[en] marl
Description
Marl is a sedimentary rock made of clay and limestone, which belongs to the family of pelitic rocks (clays <0.02 mm, the fine particles in water sales) and a carbonate is a variety of mudstone. The rocks can be both clastic and chemical-biogenic origin. The carbonate can be washed in as detritus, often goes back to the carbonate skeletons of plankton or biochemically precipitated calcite. On the seabed to collect layers of calcite and clay sediments, which are becoming more powerful over time and compacted by the weight of younger sediments onlay. Furthermore, responding in the sediment pore solution with the mineral matter and the sediment is gradually changing into a rock. The trivial term ruin marble (also landscape marble) refers to limestone and marl (as calcitic overprinted mud stones). Color

green, brown, beige and gray - grayish white
Grain Size
very fine grained
sandstone are deposit in southern California
Igneous Rock
Igneous rocks are formed when molten rock (magma) cools and solidifies, with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from either the Earth's mantle or pre-existing rocks made molten by extreme temperature and pressure changes. Over 700 types of igneous rocks have been described, most of them formed beneath the surface of the Earth's crust. The word "igneous" is derived from the Latin ignis, meaning "fireGujarat has vast resources of marble in Banaskantha. Bharuch. Vadodara. Kaclichh and Panchmahal … In Uttarakhand. thick impersistent bands of white marble occur inBasalt is a very common igneous rock. In fact it is the most common rock in the Earth's crust. Almost all oceanic crust is made of basalt and basalt is a common extrusion from many volcanic regions around the world. It forms from the melting of the upper mantle and its chemistry closely resembles the upper mantle's composition. It is generally silica poor and iron and magnesium rich. Basalt originates from "hot spot" volcanoes, massive basalt flows and mid oceanic ridges.Uses of Basalt Basalt is used for a wide variety of purposes. It is most commonly crushed for use as an aggregate in construction projects. Crushed basalt is used for road base, concrete aggregate, asphalt pavement aggregate, railroad ballast, filter stone in drain fields and may other purposes. Basalt is also cut into dimension stone. Thin slabs of basalt are cut and sometimes polished for use as floor tiles, building veneer, monuments and other stone objects.Rock Salt?Rock Salt is a chemical sedimentary rock that forms from the evaporation of ocean or saline lake waters. It is also known by the mineral name "halite". It is rarely found at Earth's surface, except in areas of very arid climate. It is often mined for use in the chemical industry or for use as a winter highway treatment. Some halite is processed for use as a seasoning for food.Rock Salt: The specimen shown is about two inches (five centimeters) across.| |

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