Monday, March 29, 2010

How geology affected both ancient and modern human settlements.

Primitive tribe were attracted towards the forest and hilly terrain of Jharkhand state, India.
by
Dr. Nitish Priyadarshi




Geology has a remarkable influence on our lives today, as it has on all life since the beginning billions of years ago. Perhaps the clearest influence we see of this is through the development of wealth from the exploitation of fossil fuels and mineral resources, including precious metals and gems. Wars have been fought over (and with) these resources, and for the potential wealth they represent. However, geology has other profound, if less glamorous, impacts on civilization, both past and present. For example, the productivity of soils critically depends on the underlying geology—both for its mineral composition and its capacity to store water. Geology also determines the shape of our landscapes—that is, before being disturbed by humans—and it is the shape of the land that has determined the distribution of human populations throughout our history.

Back at the dawn of human civilization when we lived along the Nile, the river regularly flooded and would bring nutrients and minerals back to the croplands. That is what sustained early human civilization. The dawn of agriculture was dependent on the flooding of a river. Had that river not flooded and that land been farmed over and over again from generation to generation, the civilization there would have died due to malnutrition. It could not have sustained itself.

The origin of urbanization had been sought from speculations and deductions of observable facts. The first cities must have originated from the development of settled agriculture, where agriculture economy in which the cultivation of cereals was an important element.

The first civilization originated along the river valleys as the water played major role in both day to day life and in agriculture.

The earliest examples of the urban development originated on the bank of the Tigris and the Euphrates between 5000 to 3000 B.C. Various technological inventions such as the wheeled cart, ox-drawn plough, sailing boat, system of canal irrigation, development of pottery and metallurgy brought changes in the economic and social organization.

The main geological factors influenced the ancient urbanization are as follows:-
1. Nature of the topography.
2. Local weather conditions.
3. Availability of water.
4. Quality of soil.
5. Nature of surface and sub-surface water.
6. Presence of minerals and rocks.

The influence of these factors varied from time to time in various forms and on the sizes of rural settlements.

Certain factors were considered by our ancestors when the site was selected for settlement such as availability of water, high ground in easily flooded areas etc. Japanese farming villages for example are tightly packed together, so that only the narrowest passage ways remain between the houses. This reflects the need to allocate every possible square meter of land for farming.

Hills:

In early period people led an insecure life especially in the border areas. In such places the settlements were either located on top of a hill or in the meander loop of a river or on high place near valleys to assure protection. Hills and mountains also provided caves to early settlers as their natural home.

Durham in England was built on a hill protected on three sides by the meander of the river water. Pithoria, near Ranchi city in Jharkhand State of India, was also selected as the earlier capital town (1st century AD) by Munda tribe because from one side there is steep valley and from other side it is covered with hills. It acted as natural protection from the invaders.


Pithoria was also rich in ground water reservoir which also attracted the early settlers like Munda and Nagvanshi rulers to develop this area as their first capital.

Rocks as building material:

Rocks were earlier used as the building material especially sandstone. Many such ancient buildings and temples are found in India where sandstone and granites were used.

Sandstone has a long history in the building industry. The stone generally has a uniform texture and it is somewhat soft, making it a user-friendly stone for a variety of applications. It is favored for wall claddings because of its low absorption rate, high compression strength and aesthetically pleasing appearance. Its appearance and high durability make it ideal for flooring as well. With a variety of colors and finishes, it is also easy to match it to nearly any décor.Massive sandstones consisting of closely interlocking and angular grains and free from structural defects were found best for building purposes. Most of the sandstones used in the buildings in ancient city of Varanasi in India, may have been supplied from Vindhyan System. The Vindhyan sandstones are fine grained in texture and available in abundance in a variety of colours like white, cream, and deep red and grey etc.Vindhyan sandstones are regularly quarried in area very near to Varanasi in Uttar Pradesh.

The stone is a common paving material because it can be highly weather resistant. Due to such quality these stone was used in mass scale in constructing stairs near the banks of the holy river Ganges in India. As a paver, sandstone is prized for its ability to maintain age and appearance over time, as well as for the different dimensions available.
Sandstone pavers can be used for patios, pool surrounds, pool coping, balconies, as well as cladding and veneer.
The color of sandstone is extremely varied and depends on the quantity and color of the cementations materials present and the overall color of the mineral grains. Sandstone spans the full spectrum of colors, ranging from sandy yellows to deep gold, pale pinks and light greens.
Light colors generally result from the absence of cementitious materials, or joined by calcite or quartz. Buff, brown and red colors result from the presence of limestone and hematite. Greensand, a type of green sandstone, results from the presence of glauconite.

Water:

Perhaps the essential ingredient to any viable civilization is access to water. Nearly all the great civilizations the world grew up around water, which provided the key not only to supplying freshwater, but also to agriculture, trade, transport and defense. Such civilizations as the Roman Empire, Egyptian Civilization, the Venetian Empire and the Omayyad Dynasty were all founded on their access to water, which provided their population with the means to both survive and expand.

Water is a vital need and man from time immemorial settled nearer to the source of water. In some places especially in limestone region people select the spring locations the site for settlements. These springs occur in a line at the line of contact of the permeable and impermeable layer. Such settlements are referred to as spring line settlements e.g. spring line villages are seen in South Dover in England and in Jammu and Kashmir State in India.

In dry areas settlements have the tendency to get oriented nearer to the sources of water. Hence the settlement site was located near a spring or river. These settlements were found ore are found in the dry limestone and other regions as well as in deserts.

World's major ancient civilizations flourished near river banks and deltaic sea coasts. The reason behind is the easy availability of water, a vital requirement of human beings. However, this choice of sites with easily available water has also cost dear to them. The change of river courses and sea level fluctuations led to the devastation of well-established civilizations. The drowning of ancient settlements due to raised sea level, forms the common subject matter of interest to marine archaeologists and marine geologists. While, marine archaeologists pay more attention to cultural aspects of those ancient people, marine geologists are interested in sea level fluctuations that cause the rise and fall of these civilizations. Marine archaeologists make use of artifacts, whereas marine geologists utilize the sediments and marine organisms to unravel the past. Since the common aim of both, the marine geologists working on palaeoclimate and the archaeologists is to illuminate the past, it becomes necessary to bring coherence between the two. In the Indian context, some attempts were made to use the understanding of sea level fluctuations to explain the archaeological discoveries. Nigam et al. (1990) collected the evidences of sea level fluctuations from religious, archaeological records and successfully supplemented with inferences from the marine geological studies.

Discovery of Lothal dockyard (first naval dockyard of the world as claimed by archaeologists) in Gujarat and drowning of Dwarika on the west coast and Pumpahar on the east coast of India are important examples of the role of the sea level fluctuations in shaping the history of mankind in this part of the world. The discovery of the Lothal dockyard, an important and famous name in Indian cultural heritage, provides evidence of ancient Indian interest in maritime activities around 4500 years B.P.

The Ganga-Ganges, especially, is the river of India, around which are intertwined the countries memories, culture and history. She has been a symbol of India's age-long culture and civilization, ever changing, ever flowing, and yet ever the same Ganga-Ganges.

The history of Ganga-Ganges is as long as the history of Indian civilization. It was in this plain that the great kingdoms of Magadha, Gupta, and Mughals found their home. It is also the region that created one of the most homogenous cultures of all times in the civilizations of the world. It was also the place which created the essence of Hinduism, Buddhism, Jainism, and Sikhism.


In the low lying areas and the delta areas, which were prone to floods and in the equatorial regions where damp and marshy conditions prevailed, settlements had the tendency to seek dry sites. Generally the hill site some 30 m above the surface land were preferred. Still today they are following the same pattern. Such settlements are known as dry point villages.

The foot hill region offers some possibilities for settlements. The foot hill region has the advantage of collecting products from the mountains as well as from the adjacent plains.

Volcanoes:

Volcanoes are also playing major role from ancient civilization to present. Volcanoes are known for their violent eruptions and lava flows, but there are many benefits that volcanoes provide for society. Volcanoes help enrich soil for farming and in some cases provide reservoirs for the storage of ground water. Moreover the earth's valuable resources are formed in volcanoes. These elements include fluorine, sulfur, zinc, copper, lead, arsenic, tin, molybdenum, uranium, tungsten, silver, mercury, and gold. Society makes use of all of these elements that volcanoes help to provide. Geothermal power is an alternate energy source that is better for the environment and volcanoes provide this to society also. Although volcanoes have the reputation of being very dangerous, (Volcanoes can kill people and animals. They can be very destructive.) There nevertheless are advantages of living near a volcano.


When a volcano erupts it throws out a lot of ash. At short notice this ash can be very harmful to the environment, but on the long term the ash layer, which contains many useful minerals, will be converted to a very fertile soil.


Close to an erupting volcano the short-term destruction by pyroclastic flows, heavy falls of ash, and lava flows can be complete, the extent of the damage depending upon the eruption magnitude. Crops, forests, orchards, and animals grazing or browsing on the volcano's slopes or surrounding lowland can be leveled or buried. But that is the short-term effect. In the long run, volcanic deposits can develop into some of the richest agricultural lands on earth.



One example of the effect of volcanoes on agricultural lands is in Italy. Except for the volcanic region around Naples, farming in southern Italy is exceedingly difficult because limestone forms the basement rock and the soil is generally quite poor. But the region around Naples, which includes Mount Vesuvius, is very rich mainly because of two large eruptions 35,000 and 12000 years ago that left the region blanketed with very thick deposits of tephra which has since weathered to rich soils. Part of this area includes Mount Vesuvius. The region has been intensively cultivated since before the birth of Christ. The land is planted with vines, vegetables, or flowers. Every square foot of this rich soil is used. For example, even a small vineyard will have, in addition to grapes and spring beans on the trellises, cauliflower and onions between the trellis rows, and the vineyard margin rimmed with orange and lemon trees, herbs, and flowers. It also is a huge tomato growing region.


The verdant splendor and fertility of many farmlands of the North Island of New Zealand are on volcanic soils of different ages. Volcanic loams have developed on older (4,000 and 40,000 years old) volcanic ash deposits of the Waikato and Bay of Plenty regions. Combined with ample rainfall, warm summers, and mild winters, these regions produce abundant crops, including the kiwifruit found around the world in modern recipes. The altered volcanic ashes are well-drained, yet hold water for plants, and are easily tilled. Deep volcanic loams are particularly good for pasture growth (there is a large New Zealand dairy industry), horticulture, and maize.
Nearly everywhere volcanoes are located people use the rich soil for farming. Even after an eruption people still return because of the fertile soil around the volcano.

Rocks and minerals:

In ancient days rocks and minerals played the important role for the earlier settlements. Best example is that of Jharkhand State of India, where the primitive tribe like Asur and Birhors were attracted towards the forest and hilly terrain of this state. Causes may be the presence of minerals and stones. Iron-smelting used to be the principal occupation of the Asurs. Asur used to extract iron ore for iron smelting from the laterite rocks present in this state.


A study of the early iron technology of Bihar, Jharkhand and West Bengal state in India, is of special importance from the point of view of proper understanding of the nature and character of iron age cultures which developed and flourished in this region during the period ranging from protohistoric to the historical period. The early beginning of the use of iron in this region was initially noted in the late Chalcolithic cultural phase.


Since the beginning of civilization, people have used stone, ceramics and, later, metals found on or close to the Earth's surface. These were used to manufacture early tools and weapons, for example, high quality flint found in northern France and southern England were used to create flint tools. Flint mines have been found in chalk areas where seams of the stone were followed underground by shafts and galleries. The mines at Grimes Graves are especially famous, and like most other flint mines, are Neolithic in origin (ca 4000 BC-ca 3000 BC). Other hard rocks mined or collected for axes included the greenstone of the Langdale axe industry based in the English Lake District.
The oldest known mine on archaeological record is the "Lion Cave" in Swaziland. At this site, which by radiocarbon dating proves the mine to be about 43,000 years old, paleolithic humans mined mineral hematite, which contained iron and was ground to produce the red pigment ochre. Mines of a similar age in Hungary are believed to be sites where Neanderthals may have mined flint for weapons and tools.

The study of rocks and minerals is one of the taproots of science, perhaps not as deep as astronomy, but extending well back into prehistory. Paleolithic people recognized and sought specific rocks and minerals for cutting tools, pigments, and various practical, religious, or artistic objects. The first minerals that were known and sought for their favorable properties were micro-crystalline ( micro crystalline means too small to be seen without a microscope) varieties of quartz, particularly flint.
Reference:

NIGAM, R., HASHIMI, N.H. and PATHAK, M.C. (1990) Sea level fluctuations: Inferences from religious and archaeological records and their oceanographic evidences. Jour. Mar. Archaeol., v.l, ñp.16_18.

http://www.naturalnews.com/020072.html
http://web.bcsdny.org/flhs/science/greece/
http://www.umich.edu/~gs265/society/volcanoes.htm
http://volcanology.geol.ucsb.edu/soil.htm
http://drs.nio.org/drs/bitstream/2264/241/1/J_Geol_Soc_India_59_583.pdf
http://unesco.uiah.fi/water/material/03_water_and_civilisation_html

Monday, March 22, 2010

Dasam falls a tragic picnic spot in Jharkhand State of India. Rocks structure plays major role.

Geological factors may be responsible for such accidents.
Potholes present in the rocks are dangerous.
by
Dr. Nitish Priyadarshi

Waterfalls offer breathtaking views and are cool places to relax and feel the astounding beauty and benefits of nature. But in some cases, these wonderful gifts of nature to mankind bring tragedy to people.

A fun filled day out at the famous Dasam falls, near Ranchi city, proved fatal for four youngsters. They drowned while enjoying a picnic on Saturday (20th March).

This is not the new case. Every year many people die in this fall especially from November to March. Causes of deaths were due to drowning.

The Dasam (meaning ten) falls also known as Dasomghagh, 40 Kms south-east of Ranchi city near Taimara valley is formed by the Kanchi river falling over a ledge of a rock in a sheer descent of 114 feet amid rocky and sylvan scenery.

There are different mythological stories behind such accidental deaths. But no scientific investigations have been done to know the exact cause of sudden drowning.

I have tried to point out some geological factors which may be responsible for such accidents.

In spite of great falls like Hundru and Jonha deaths occurs only in Dasam falls. Geological cause behind this is the rock structures. Surface rocks surrounding the area are highly smooth. This is due to abrasion. Abrasion is the mechanical scraping of a rock surface by friction between rocks and moving particles during their transport by wind, glacier, waves, gravity, running water or erosion. This phenomenon is active there from millions of years. People wearing leather shoes or slippers are more prone to accident on this polished surface. There are more chances for the people of getting slipped inside the water and injuring their heads.

Other major factor responsible for such accidents is the presence of pot holes. Many pot holes are found in the river beds in Jharkhand state. Jharkhand rocks favor such formations. Some are such large that even the elephants can also be trapped especially in the Palamau area.
Potholes are usually regarded as one of the erosional features. The traditional interpretation is in terms of the process of abrasion of the bedrock by rotary currents inside the potholes, and vibration of pebbles and stones by the water, that gradually wore the holes deeper and deeper into the bedrock.

In the usual interpretation, potholes are considered to be the effects of erosion by streams and rivers over very long periods of time. The actual work of abrasion is considered to have been done either by hard grains of sand held in suspension by the rapidly flowing water; or by large boulders, called "grinders," in the bottom of the pothole, that were agitated constantly by the currents swirling around inside.

Strong under currents is generated when water enters such pot holes. These currents act as suction pump. When people enter in water there are more chances to get trapped and pulled inside. State government must flag such dangerous potholes in Dasam falls and people must be warned of such areas.

Even the crevices or the long gaps present in the rocks beneath the water are dangerous. People entering the water are unaware of such crevices or gaps between the rocks. They are the silent killers. Rocks around such falls in Ranchi district are filled with crevices and depressions.

As Dasam falls is flooded with people during the season, it is more prone to such accidents. Rocks beneath the water and surrounding play a major role to make this spot picturesque. But they also act as killer stone.

Thursday, March 18, 2010

Global warming controversy.

Can we predict effects of climate change with accuracy?
by
Dr. Nitish Priyadarshi
Recently all the newspaper of world was heated up with the discussions about the so called glaciers melting of Himalayas by 2035, from IPCC. Other prediction was about Amazon rain forests. The IPCC maintained that there would be a huge depletion in Amazon rain forests because of lack of precipitation. There are many more predictions given by IPCC which I think that they are over exaggerated and could not be believed. Regarding glaciers melting by 2035, it is now being defended as a minor error (it was originally meant to be 2350, some have clarified).

The global warming controversy is a dispute regarding the nature, causes, and consequences of global warming. The disputed issues include the causes of increased global average air temperature, especially since the mid-20th century, whether this warming trend is unprecedented or within normal climatic variations, whether humankind has contributed significantly to it, and whether the increase is wholly or partially an artifact of poor measurements. Additional disputes concern estimates of climate sensitivity, predictions of additional warming, and what the consequences of global warming will be. The controversy is significantly more pronounced in the popular media than in the scientific literature, which generally asserts that recent global warming trends have been significantly influenced by human activity.

It is not the question that how much we can believe on such predictions, but the question is can we predict the effects of global warming or climate change with accuracy? The way the increasing trend of global warming is shown or predicted, it seems that in coming 30 to 40 years earth will be totally devoid of any life and earth will die. I don’t think so. It is also true that earth is warming but not in the way it is shown but the warming trend of the earth is similar to that in geological past. Even most of the effects of the warming or climate change forecasted have failed. Regarding effects of global warming, I would like to quote one example form my state of Jharkhand in India. From last fifteen years we are predicting that in coming five years Jharkhand will be devoid of groundwater, but still the groundwater is there. Though it is depleting but not in the way we have predicted. Main cause of the depletion of the ground water level is due to over exploitation, and that is only for few months. In every rainy season groundwater level comes up.

Is really global warming is there or we are just exaggerating it? It is said that main cause of the global warming is due to increase in carbon dioxide level in the atmosphere. Between 1940 and 1970, global temperatures went down slightly, even though carbon dioxide levels went up. This has been attributed to the cooling effect of sulphate aerosols.
Studies of ice cores show that carbon dioxide levels rise and fall with or after (as much as 1000 years) temperature variations. This argument assumes that current climate change can be expected to be similar to past climate change.


Seeing this year cold waves in India and heavy snow cover in total Northern Hemisphere common people put the question mark on the global warming concept. . If we believe on the scientific evidences about the climates in the past geological history we have passed through different hot periods greater than today. So global warming is not recent phenomenon and also we can’t stop it.

Saturday, March 13, 2010

Crows and Eagles were found dead near Ranchi city of India.

They were found dead today in outskirts of Ranchi city.
by
Dr. Nitish Priyadarshi







These are the pictures of the dead birds mostly crows and eagles. They were found dead today in outskirts of Ranchi city in Jharkhand State of India.Villagers saw them in the morning. Their sudden deaths are shrouded in mystery as birds seldom die suddenly. I am sure they must have eaten some poisonous foods or may have been infected by some deadly virus. Some of the dead bodies were also found hanging on the trees. Area where their bodies were found is devoid of thick vegetation and civilization. It is barren land. Now a day very less crows are seen in and around Ranchi city. Most of the birds like sparrows are now gradually vanishing from the city.

According to recent report, The American crow is very susceptible to the West Nile virus, a disease just recently introduced in North America. American crows usually die within one week of acquiring the disease with only very few surviving exposure. Crows are so affected by the disease that their deaths are now serving as an indicator of the West Nile Virus’ activity in an area.
Crows know how to be their own doctors, it seems. Ants have acids and fluids that help rid crows of parasites. Crows have been observed stretching out on anthills and allowing ants to cover them, and sometimes they crush the ants into their feathers. Evidence indicates that this behaviour is learned and passed down to other generation within crow family groups.


Wednesday, March 10, 2010

Increasing trend of CO2 level.



CO2 Data Set:
Original data file created by NOAA on Wednesday February 10, 2010 (10:13:56)
Measuring Location: Mauna Loa Observatory, Hawaii

Data Source: Earth Systems Research Laboratory (ESRL) / National Oceanic and Atmospheric Administration (NOAA)
Why is CO2 significant?
Carbon dioxide (CO2) is the chief greenhouse gas that results from human activities and causes global warming and climate change. To see whether enough is being done at the moment to solve these global problems, there is no single indicator as complete and current as the monthly updates for atmospheric CO2 from the Mauna Loa Observatory.
What is the current trend?
The concentrations of CO2 in the atmosphere are increasing at an accelerating rate from decade to decade. Accelerating from decade to decade. The latest atmospheric CO2 data is consistent with a continuation of this long-standing trend.
What level is safe?
The upper safety limit for atmospheric CO2 is 350 parts per million (ppm). Atmospheric CO2 levels have stayed higher than 350 ppm since early 1988.

Ancient climate indicator rocks are also found in Jharkhand State of India.

The formation of some rock types and minerals are directly influenced by aspects of climate.
by
Dr. Nitish Priyadarshi

Palaeoclimatology, the study of climates during the geological past, is one of the most topical areas of research in the geosciences at present. The threat of future climate change caused by higher levels of greenhouse gases, which would drastically alter many aspects of our environment, has prompted much research to try to understand how our complex climate system works. Only by understanding how climate has evolved over million of years can we identify important climate cycles with a frequency in excess of the short climate records we possess. These climate cycles have the potential to have a profound effect on our environment.

Understanding our climate history in the geological past is also important for climatologists trying to construct accurate numerical computer models of our present climate system to use for predicting future climate change.

Basic information about past climates comes from understanding how climate influences certain sedimentary systems, floras and faunas on earth today and extrapolating this information back to interpret geological evidence.

The formation of some rock types and minerals are directly influenced by aspects of climate. Some of the most useful are coals, evaporates, glacial deposits, Bauxite and carbonates. I am presenting only a brief resume of rocks and minerals as a paleoclimatic indicators in Jharkhand State of India.

Coal:
Coal is a compact stratified organic rock composed largely of metamorphosed plant remains mixed with a variable but subordinate amount of inorganic material. The coal-forming plant material may have accumulated where it grew or may have been transported to the depositional site by water or wind. The accumulation of peat requires a humid climate to support a rich growth of vegetation and a high water table to permit prolonged accumulation of plant material in a reducing environment. In other words, the presence of coal, initially formed from the accumulation of plant material as peat, is generally taken to indicate warm and wet humid climates ideal for lush plant growth, and where the rainfall is higher than the rate of evaporation, such as in equatorial regions.

In the past, the most abundant coal deposits were formed during the Carboniferous when large subsiding continental areas were situated in low latitudes and experienced hot and humid climates. The great Carboniferous forests were composed of the pithy-stemmed clubmosses and lycopods, such as Lepidodendron, Siggillaria and Calamites, which grew to giant sizes in the hot wet conditions and formed thick layers of peat as they collapsed into waterlogged swamps. The disappearance or decrease in size of these water loving plants at the end of the Carboniferous marked the onset of much drier conditions in low-latitude regions during the Permian.

A discussion on depositional environment of Permian peat swamps phases may well be preceded by the remarks that, Karharbari, Barakar and Raniganj ( these are all different coal formation stage) stages of Lower Gondwanas of Jharkhand State of India, were climatically controlled. The climate during Karharbari period was rather cold as evidenced by flora and by possible effects of glaciation in Talchir series. On the contrary, climate during Barakar and Raniganj commenced with coal and humid climate gradually becoming warmer and humid as evidenced by flora and coal composition.

Glacial deposits:

Evidence for glaciation and the presence of thick ice sheets can be obtained from a variety of sources. The most convincing are striated pavements, that is surfaces of bedrock with grooves scratched by debris frozen into the base of moving ice glaciers. The orientation of ice movement and therefore in some cases the position of glacial centres can also be determined. Till or tillites can also provide information about ice passage. The term till was originally applied in Scotland to a stiff, hard clay subsoil, generally impervious and unstratified, often containing gravel and boulders. In present usage, the word till means a clastic glacial deposit, usually poorly sorted and nonstratified, and derived from glacial drift; it consists of a heterogeneous mixture of rock and mineral fragments of varied lithologic composition, size and shape. If till is indurated by cementation or metamorphism, it is called tillite.

Evidences of tillites are found in different coalfields area of Jharkhand State.

Bauxite:
Bauxite is not a product of normal weathering in temperate regions, it is almost entirely lacking from soils formed there. It is however, a constituent of laterite soils formed in tropical and subtropical regions. They have mostly been formed in the late Mesozoic or Tertiary time under climate conditions different from those that prevail in the same places today. Possibly some of the conditions that affected the change from the age of reptiles to the age of mammals likewise promoted the formation of bauxite.

The conditions necessary for bauxite deposits are humid tropical or subtropical climate. It has been shown that a temperature above 20 degree C favors chemical processes by which SiO2 goes into solution and Fe2O3 and Al2O3 remain behind. The wet season of the tropics is one of formation of Al2O3 and Fe2O3, the dry season one of leaching of silica away from these oxides. This may supply the answer to why a tropical climate is necessary for bauxite formation.
Bauxite are found in Lohardaga and Netharhat areas of Jharkhand State.

Saturday, March 6, 2010

Copper deposits in India.

Hindustan copper ltd. (HCL) is presently the sole indigenous producer of primary copper in the country. The all India recoverable reserves of copper ore are placed at 431.046 million tonnes equivalent to about 4.557 million tonnes of metal content. The prospective resources are placed at 769.90 million tonnes of copper ore.
Copper concentrated states are, Andhra Pradesh, Jharkhand, Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Meghalaya, Orissa, Rajasthan, Uttar Pradesh and West Bengal.
Recently in Jharkhand copper mining has been stopped due to involvement of more money and less profit only one mine is working.
Boreholes drilled in Chitar sector in Pali and Ajmer districts in Rajasthan have intersected ore zones, varying in width from 0.55 to 9.8 m. The zones contain grade ranging between 0.5% and 1% Cu and 1% and 2%zinc. Drilling investigation in Dariba (Akola) copper prospect, Rajasthan, has indicated about 2 million tonnes of copper ore. The test drilling by GSI at Saran Bhawavat in Udaipur district of Rajasthan has shown copper mineralization varying between 0.4% and 1% copper in the first borehole.

In Puranapani area, West Bengal, significant copper mineralization in association with the quartz vein intruding the mica schist came to light during the course of tungsten exploration by GSI. During geochemical appraisal of Dobri-Pingalpani area in Chamoli district, Uttar Pradesh, two silicified zones were noted in Trini-Koteshwar area, analysing 0.55 to 0.72 % Cu. Recoverable reserve of 0.987 million tonnes having 11.65 thousand tonnes of metal has been estimated from the district of Pithoragargh in UP/Uttaranchal.

In Maharashtra copper has been reported from the district of Nagpur where the reserves of recoverable ore is said to be 0.142 million tonnes having 1.908 thousand of tonnes of metal in it.

In Orissa the district of Mayurbhanj and Samabalpur have been reported to have a total of 1.65 million tonnes of recoverable reserve of copper ore with 1820 thousand tonnes of metal content in it.

Madhya Pradesh was the leading producer of copper ore contributing 39.7% to the Indian production followed by Rajasthan (33.7%), Jharkhand (24.7%) and Karnataka (1.8%). Nominal production was also reported from Orissa and Sikkim.


Jharkhand has the reserve of 93.06 lakh tonnes, which is about 25.94% of India’s total deposits. Copper deposits extend in a linear belt of 130 km length and 17km width. This belt exists from Chakradharpur to Simgri (Bahragora) through Kharsawan, Saraikela and Dhalbhum. GSI (Geological Survey of India) has tentatively estimated 1.59 million tonnes of copper ore, containing 2.36% copper, in the Dhobani area. A recoverable reserve of 0.35 million tonnes of copper ore, which might yield 5.75 thousand tonnes of metal, has been estimated from the district of Hazaribag. Further possibility of its existence lies in the districts of Giridih, Sahebganj, Palamau and Garhwa.