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Significance of rock fragments and mineral grains in river sands.

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River sands of Ranchi plateau consists quartz, quartzite, feldspar, mica, coals, etc. by Dr. Nitish Priyadarshi Sand grains of Ranchi river showing rock particles and other minerals. Sand has become a very important mineral for the expansion of society. Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. River sand is one of the world’s most plentiful resources (perhaps as much as 20% of the Earth’s crust is sand) and has the ability to replenish itself. River sand is vital for human well being & for sustenance of rivers. Rivers are hydraulically complicated and can vary greatly in source materials. Therefore, nearly all river sands show a broad spectrum of textures within the same deposit. Sand deposits of the rivers are accumulations of rock fragments and mineral grains, which have been derived from the weathering and erosion of hard rocks by glacial and river action. Water action is an effective mechanism for wearing away weak...

People of Ranchi in India witnessed huge halo formed around the Sun.

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Blazing hot sun had a huge halo formed around it. by Dr. Nitish Priyadarshi On Sunday, Ranchi people witnessed a spectacular natural phenomenon in the sky. The blazing hot sun had a huge halo formed around it. City people and those in the outskirts watched in wonder as the giant ring, also referred to as 22° halo, was visible around the sun for over an hour in the afternoon. While many braved the summer heat to climb to rooftops to take photographs of the halo, it also caused panic in some. Apart from the state capital, other cities across the state like Jamshedpur, Hazaribag and Dhanbad also witnessed the phenomenon. Halos are rings of light that can encircle the sun or the moon, and they usually occur when a thin layer of cirrus clouds are present in the sky. Most halos appear as bright white rings but in some instances, the dispersion of light as it passes through ice crystals found in upper level cirrus clouds can cause a halo to have color. A halo (also known as a nimbus , iceb...

Mystery of Orbs ?

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Is it a dust pollution or some biological or organic charged particle? by  Dr. Nitish Priyadarshi  Two orbs are seen in the above picture. The term orb describes unexpected, typically circular artifacts that occur in flash photography—sometimes with trails indicating motion—especially common with modern compact and ultra-compact digital cameras. Many people capture illuminated, circular spots in their photographs. These spots are commonly known as orbs. Having been a photographer for 30 years, I’ve experienced all kinds of flaws, defects and other apparitions on my negatives and now digital images.  Most have been identified or at the least, understood to be some kind of image pollution ranging from light leaks, lens flares, dust, fog or other type of atmospheric condition.  Since the advent of digital imaging however, there is a new phenomenon called “orbs” that are appearing in increasing numbers on many photographer’s images today. I started to become aware of ...

Dome gneiss hill near Ranchi city of India.

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It is formed mainly by weathering and erosion. by Dr. Nitish Priyadarshi Geologist. Above pictures are of Dome gneiss hill. This typical dome-gneiss (locally known as dongris) 26 km from Ranchi on Ranchi-Bundu highway (85 0 27 ” longitude and 23 0 14 ” latitude) has slopes on all sides (the average inclination being about 40 degree to 50 degree). There is little soil but oozing moisture from rock foliae supports tuft grass except the entirely bare rocky surfaces. A dome is a curved formation or structure. It is shaped like half of a sphere. Imagine cutting an orange in half, and placing it cut-side-down on a table. This is the shape of a dome, although most domes in nature are not perfectly rounded. Some natural domes develop when magma from deep within the Earth pushes up surface rock layers. This type of geologic dome can form as magma intrudes between two layers of sedimentary rock. The magma creates a dome or triangle shape as it pushes the other layers apart. The hardened magma ...

Fuller’s earth mining in Pakur district in Jharkhand State of India.

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Bentonite may have played a major role in Fuller’s earth formation. By Dr. Nitish Priyadarshi   Fig. Mining of Fuller's earth.  Fig. Fuller's earth.  Fig. Mining area. Fig. Bentonite. Abstract: Pakur   is located in the north east corner of Jharkhand State of India. Major part of the district is characterized by undulating topography covered by basaltic flows of Rajmahal Trap. Fuller’s earth mining is limited up to a shallow depth only and it is done manually. Most of the Fuller’s earth is send to local market of Pakur and neighboring state of West Bengal. Local villagers have the ownership of the mining and the profit is distributed among them. Fuller’s earth is mainly of sedimentary origin. It occurs interstratified with geologically late sands and clays. It is thought that most fuller’s earth originated from volcanic ash. Montmorillonite and attapulgite are the principal constituents, and montmorillonite is characteristic of bentonite. There is further suggestio...

Geology of Dasam Falls in Ranchi district of Jharkhand State, India.

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 The Dassam Fall is a natural cascade across the Kanchi River. by Dr. Nitish Priyadarshi Geologist A waterfall is a place where water flows over a vertical drop in the course of a stream or river. Waterfalls are also called cascades. Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens slowly, while downstream the erosion occurs more rapidly. As the watercourse increases its velocity at the edge of the waterfall, it plucks material from the riverbed. Whirlpools created in the turbulence as well as sand and stones carried by the watercourse increase the erosion capacity. This causes the waterfall to carve deeper into the bed and to recede upstream. Often over time, the waterfall will recede back to form a canyon or gorge downstream as it recedes upstream, and it will carve deeper into the ridge above it. The process of erosion, the wearing away of earth, plays an im...

Rock paintings dating back thousands of years ago have been found on the hill in Ranchi city, India.

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Hand Print was found in a rock shelter. By Dr. Nitish Priyadarshi Fig. Hill near Ranchi where Rock painting was found. A few days ago, during my geological trip to the near by hills in Ranchi city of Jharkhand state of India , I had the opportunity to see rock art for the first time in the city. These rock paintings were found on a hill some 5 kms North of Ranchi city. This hill is composed of granite gneiss rocks. Earlier I saw such paintings far away from the Ranchi city in the villages or in remote areas during my field studies. Fascinated by the detail of their making, I chose them as the subject with geology.  Currently, as a researcher in Geology, I am elaborating on this topic further by studying the engravings of such paintings on the rocks of Ranchi Plateau. There are abstract of geometric symbols, parallel lines, and fence-like patterns. Other symbols hand- and footprints, dancing images etc. Most of the symbols were drawn with great care and were obviously arranged wit...