Friday, July 30, 2010

Platinum metal can glitter Jharkhand State of India.

Presence of platinum cannot be ruled out in Jharkhand State of India.
Dr. Nitish Priyadarshi
Platinum may be considered one of the precious metals since it is more costly than gold. About 60 percent of that consumed in the United States is for jewelry purposes. It was once used for coinage in Russia until its value exceeded that of the coins. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River. The metal has an excellent resistance to corrosion and high temperatures and has stable electrical properties.

Platinum is only one of a group of related metals consisting of osmium, iridium, palladium, rhodium, and ruthenium. They are not only associated together but also are generally alloyed, and are called, therefore the “platinum metals.” They are very heavy, insoluble in most acids, melt at temperatures of 1,549 degree to 2,700 degree C, and range in hardness from 4.8 to over 7. Iridium is the heaviest metal and osmium the hardest.

Platinum is invariably associated with basic igneous rocks and with the ore minerals characteristic of these rocks. Most of the platinum of the world is intimately associated either with chromite or nickel. Even platinum placers are derived from basic rocks rich in chromite. The platiniferous nickel ores also contain copper and appreciable quantities of gold and silver.

In India, reported values of platinum group of metals worthy of attention are from the pre-cambrian mafic/ultramafic complexes in Sukinda and Nausahi sectors of Orissa and Sitampudi in Tamil Nadu. Geological Survey of India carried out sampling of the chromite ore bodies and their associated rocks. It was observed that the incidence of Platinum group of metals is much less in chromite bodies but it is somewhat more, of 20 to 100 ppb (parts per billion) in the chromite horizons.

Seeing the association of platinum with chromite and its deposits in ultramafic rocks in Jharkhand state of India, presence of platinum cannot be ruled out. Till today no detail research work has been done on the possibilities of platinum in the chromite deposit areas in Jharkhand State. Jojohatu, Hatgamariya, Keshargariya, Roroburu, Chitungburu, Kimsiburu, Kittaburu, Kusmita, Gurgaon, Tonto and Janoa-Ranjrakocha areas must be targeted for platinum deposits.

Chromite deposits of Jharkhand had a pioneering role in the early history of chromite exploitation in India. Small deposits of chromite ore are confined to the southern part of Singhbhum district in Jharkhand. Such deposits are exposed around Jojohatu, Hatgamariya, Keshargariya, Roroburu, Chitungburu, Kimsiburu, Kittaburu. Small occurrences of chromite are also found at Kusmita, Gurgaon, Tonto and Janoa-Ranjrakocha areas. Many of the deposits have been prospected by private parties but abandoned afterwards. The deposits are rather scattered and small and the grade is generally inferior (30-40% Cr2O3).

Jojohatu lies about 25 km to the west of Chaibasa, the district headquarters of Singhbhum. The Jojohatu ultramafic body is spread in three blocks with a cumulative length of 8 km in N-S direction and over a width of 3 km. These blocks are named successively from North to South as Kimsiburu, Kittaburu and Roroburu-Chitungburu. The ultrabasic rocks with which chromite is associated is intrusive into the rocks of Iron Ore Super Group represented in the area.

In one report of B.D. Sharma and others, Chalcopyrite concentrates from the Singhbhum district, India, contained 25-70 ppb Pt, which is greater than amounts found in rocks and chromite. Platinum group of metal are also reported in Kinkel and Kurdeg area of Simdega District.

Sharma, B.D. Economic Geology; May 1966; v. 61; no. 3; p. 592-597; DOI: 10.2113/gsecongeo.61.3.592

Monday, July 26, 2010

Love your environment and nature.

These are some of the beautiful places in North East India.
Dr. Nitish Priyadarshi

Meteorological phenomena influences groundwater levels.

Rainfall is not an accurate indicator of groundwater recharge.
Dr. Nitish Priyadarshi
Water is essential to people and the largest available source of fresh water lies underground. Ground water is the part of precipitation that seeps down through the soil until it reaches rock material that is saturated with water. Water in the ground is stored in the spaces between rock particles. Increased demands for water have affected the level of under groundwater. The demand for water has increased over the years and this has led to water scarcity in many parts of the world. The situation is aggravated by the problem of water pollution or contamination. World is heading towards a freshwater crisis mainly due to improper management of water resources and environmental degradation, which has lead to a lack of access to safe water supply to millions of people. This freshwater crisis is already evident in many parts of world, varying in scale and intensity depending mainly on the time of the year.

Water-level changes can be divided into several categories. There are short-term changes that can only be seen when water-level measurements are made many times a day. There are long term changes that can only be seen after data are collected for many years. There are minor changes of only a few hundredths of a foot, and changes that are hundreds of feet.

Any phenomenon that produces a change in pressure on groundwater will cause the groundwater level to vary. Differences between supply and withdrawal of groundwater cause levels to fluctuate. Other diverse influences on groundwater levels include meteorological and tidal phenomena, urbanization, earthquakes, and external loads. And, finally, subsidence of the land surface can occur due to changes in underlying groundwater conditions.

Fluctuations due to meteorological phenomena:

Atmospheric Pressure:

Changes in atmospheric pressure can also cause groundwater levels to fluctuate. Atmospheric pressure is caused by the Earth’s gravitational attraction of air in the atmosphere. At sea level, the weight of the atmosphere exerts a pressure of about 14.7 pounds per square inch on the Earth’s surface.

Changes in atmospheric pressure produce sizable fluctuations in wells penetrating confined aquifers. The relationship is inverse; that is, increases in atmospheric produce decreases in water levels, and conversely.

For an unconfined aquifer, atmospheric pressure changes are transmitted directly to the water table, both in the aquifer and in a well; hence, no pressure difference occurs. Air entrapped in pores below the water table is affected by pressure changes, however, causing fluctuations similar to but smaller than that observed in confined aquifers. Temperature fluctuations in the capillary zone will also induce water table fluctuations where entrapped air is present.


Rainfall is not an accurate indicator of groundwater recharge because of surface and subsurface losses as well as travel time for vertical percolation. The travel time may vary from a few minutes for shallow water tables in permeable formations to several months or years for deep water tables underlying sediments with low vertical permeabilities.

Precipitated water that reaches at the surface ground maybe partially discharge into streams as surface runoff or partially infiltrate into the ground. The latter further percolates into groundwater aquifers, eventually emerging in springs, seeping into streams to form surface runoff, or storing in subsurface. The soil stores infiltrated water to become soil moisture, and then it recharges to groundwater level if the soil is saturated. Nevertheless, it releases slowly as subsurface flow to enter the stream as baseflow during rainless period. This may also result from deeper percolation, evapotranspiration, or artificial discharge.

If no water supplies are continually provided from either rainfall or other sources of recharge, groundwater level would gradually decrease due to deeper percolation or evapotranspiration.

Furthermore, in arid and semiarid regions, recharge from rainfall may be essentially zero. Shallow water tables show definite response to rainfall where the unsaturated zone above a water table has a moisture content less than that of specific retention, the water table will not respond to recharge from rainfall until this deficiency has been satisfied.

Minor fluctuations of water levels are caused by wind blowing over the tops of wells. The effect is identical to the action of a vacuum pump. As a gust of wind blows across the top of a casing, the air pressure within the well is suddenly lowered and, as a consequence, the water level quickly rises. After the gust passes the air pressure in the well rises and the water level falls.


In the regions of heavy frost it has been observed that shallow water tables decline gradually during the winter and rise sharply in early spring before recharge from ground surface could occur. This fluctuation can be attributed to the presence of a frost layer above the water table. During winter water moves upward from the water table by capillary movement.

Tuesday, July 13, 2010

Mineral reserves of the world may not last long.

Known reserves of minerals may not last long.
Dr. Nitish Priyadarshi

The use of minerals has been instrumental in raising the standard of living of mankind. The names of the minerals and their products have been used to christen various eras of civilization, such as the Stone Age, the Bronze Age, the Iron Age and the Nuclear Age. The sophisticated world of today is largely the result of the enlarged use of minerals, whether it be as fertilizer for food, coal, petroleum, natural gas and atomic energy as sources of power, or countless other necessities of life, like automobiles, aero planes, ships, modern communications and a host of chemicals which are derived from the use of minerals.

Minerals thus form a part and parcel of our daily life. Since the beginning of this century the use of minerals has been greatly diversified and expanded. Their consumption has shown an unprecedented increase, year after year. It has been estimated that the quantity of mineral consumed in the last 70 years even exceeds the aggregate quantity consumed in previous human history. The sharp rise in consumption has accelerated attempts in continuous search for locating new deposits and even deeper probe into the womb of the earth and the ocean beds.

Minerals do not occur where we want them to be nor deposits become assets unless explored and developed. Experience shows that no country possesses adequate resources of all minerals. Several countries are practically devoid of mineral wealth and many have inadequate resources.
Since the future of humanity depends on mineral resources, we must understand that these resources have limits; our known supply of minerals will be used up early in the third millennium of our calendar. Furthermore, modern agriculture and the ability to feed an overpopulated world is dependent on mineral resources to construct the machines that till the soil, enrich it with mineral fertilizers, and to transport the products. As geologists, we cannot tell you that mineral resources are finite. The presently available resources were created by earth processes and after we exhaust them, more will develop in a few tens of million years, which is not in human lifespans.
Though minerals are essential for the continued industrial development, as well as for industries, the minerals often does not last long. A mineral property is a wasting asset. The reserves in a mine are continuously decreasing. It is not like agriculture where crops can be raised again and again on the same land. Some authorities apprehend that the known reserves of minerals may not last long and most of them will exhaust well within 100 to 200 years. Even the minerals which are relatively plentiful will become extremely expensive because of the depletion of large, rich and easily accessible deposits of these metals.

This prediction has got some validity in respect of expendable minerals like petroleum, and non-expendable metals like tungsten, tin, lead, zinc and mercury. In the book “Limits to Growth” by the club of Rome a great apprehension has been shown about the life of many minerals. They have calculated the life of various minerals deposits by dividing the known reserves by the total consumption at a static rate and came to the following conclusions:

Aluminium: 100 years
Chromium : 420 years
Coal : 2300 years
Cobalt: 110 years
Copper: 36 years
Gold : 11 years
Iron : 240 years
Lead: 26 years
Natural Gas: 38 years
Petroleum: 31 years
23 years

Though these predictions are old but it looks true to some extent with the existing knowledge of the reserves. A reserve of many minerals has improved due to establishment of new reserves. But the danger still exists due to the reckless mining of certain minerals like Iron, Coal etc. in many parts of the world especially in Jharkhand state of India, where Iron ore mining is done illegally and in an unscientific way.

We are now reaching limits of reserves for many minerals . Human population growth and increased modern industry are depleting our available resources at increasing rates. Although objections have been made to the Rome Report of 1972, the press of human growth upon the planet's resources is a very real problem. The consumption of mineral resources proceeded at a phenomenal rate during the past hundred years and population and production increases cannot continue without increasing pollution and depletion of mineral resources. The geometric rise of population has been joined by a period of rapid industrialization, which has placed incredible pressure on the mineral resources. Limits of growth in the world are imposed not as much by pollution as by the depletion of natural resources. As the industrialized nations of the world continue the rapid depletion of energy and mineral resources, and resource-rich less-developed nations become increasingly aware of the value of their raw materials, resource driven conflicts will increase.