Polymetallic Nodules

Posted on February 26, 2008 by Rashid Faridi

MANGANESE (OR POLYMETALLIC) NODULES: Increasing global population, demand for metals and dwindling land resources, has come to such a pass that the next alternative source for the metals could be in the world oceans. Oceans are considered as a ‘warehouse’ for minerals, amongst others, polymetallic nodules (Ferromanganese nodules), phosphorites, hydrothermal sulphides, placer deposits and sand. The first discovery of polymetallic nodules was made by scientists onboard the research vessel “H M S Challenger” during 1873. In comparison, India (by the efforts of the National Institute of Oceanography, Goa) recovered nodules in the Arabian Sea during 1981 onboard “R.V.Gaveshani.” In 1982, India was recognised as a Pioneer Investor in deep seabed mining, by the United Nations Convention on the Law of Sea.

Subsequently, a massive effort was put in by India for exploration of polymetallic nodules in the Central Indian Ocean Basin (CIOB) by using a number of research vessels. This national programme (running into crores of rupees) is being funded by Department of Ocean Development, New Delhi.

To-date, India has surveyed an area of nearly 4 million sq km in the CIOB. This resulted in the identification of two mine sites, each 150,000 sq km area with equal commercial grade (Cu+Ni+Co wt%) and abundance (kg/sq m) of nodules. In 1984, India filed her claim with the Preparatory Commission (PRECOM) for the International Sea Bed Authority (ISBA). In 1987, India became the first country in the world to be allocated exclusive rights for further exploration.

One of the mine site (A) of 150, 000 sq km has been allotted to India and as per the condition of the ISBA, 50 % of the area has been relinquished to this body.


What are polymetallic nodules and the criteria for their formation?

Polymetallic nodules are Fe-Mn oxide deposits, potato shape, porous, black
earthy colour with size ranging from 2 to 10 cm in diameter.

 

Different shapes of polymetallic nodules .

Nodules occur at nearly 4 to 5 km depth in the deep oceans and they take one
million year to grow to one millimeter.

In the Indian Ocean, nodules occur in different basins such as CIOB Wharton Basin,
Crozet Basin, Madgascar Basin, Somali Basin, South Australian Basin and Arabian sea.

The prerequisite conditions to form the nodules are:

Low sedimentation rate
Availability of nucleus around which accretion of oxides takes place
Oxidising environment
Bottom currents of low velocity

 

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Natural Resources: Definition and Classification

Posted on February 26, 2008 by Rashid Faridi

Natural resources are naturally occurring substances that are considered valuable in their relatively unmodified (natural) form. A natural resource’s value rests in the amount of the material available and the demand for it. The latter is determined by its usefulness to production. A commodity is generally considered a natural resource when the primary activities associated with it are extraction and purification, as opposed to creation. Thus, mining, petroleum extraction, fishing, hunting, and forestry are generally considered natural-resource industries, while agriculture is not. The term was introduced to a broad audience by E.F. Schumacher in his 1970s book Small is Beautiful.

Classification of natural resources

Natural resources are mostly classified into renewable and non-renewable resources. Renewable resources

Renewable resources are generally living resources (fish, reindeer, coffee, and forests, for example), which can restock (renew) themselves if they are not over-harvested but used sustainably. Once renewable resources are consumed at a rate that exceeds their natural rate of replacement, the standing stock (see renewable energy) will diminish and eventually run out. The rate of sustainable use of a renewable resource is determined by the replacement rate and amount of standing stock of that particular resource. Non-living renewable natural resources include soil and water.

Flow renewable resources are very much like renewable resources, only they do not need regeneration, unlike renewable resources. Flow renewable resources include renewable energy sources such as the following renewable power sources: solar, geothermal, biomass, landfill gas, tides and wind.

Resources can also be classified on the basis of their origin as biotic and abiotic. Biotic resources are derived from living organisms. Abiotic resources are derived from the non-living world (e.g., land, water, and air). Mineral and power resources are also abiotic resources some of which are derived from nature.

Non-renewable resources

A non-renewable resource is a natural resource that exists in a fixed amount that cannot be re-made, re-grown or regenerated as fast as it is consumed and used up.

Some non-renewable resources can be renewable but take an extremely long time to renew. Fossil fuels, for example, take millions of years to form and so are not practically considered ‘renewable’. Many environmentalists proposed to tax on consumption of non renewable resources.

Natural capital

Natural resources are natural capital converted to commodity inputs to infrastructural capital processes. They include soil, timber, oil, minerals, and other goods taken more or less from the Earth. Both extraction of the basic resource and refining it into a purer, directly usable form, (e.g., metals, refined oils) are generally considered natural-resource activities, even though the latter may not necessarily occur near the former.

A nation’s natural resources often determine its wealth and status in the world economic system, by determining its political influence in. Developed nations are those which are less dependent on natural resources for wealth, due to their greater reliance on infrastructural capital for production. However, some see a resource curse whereby easily obtainable natural resources could actually hurt the prospects of a national economy by fostering political corruption. Political corruption can negatively impact the national economy because time is spent giving bribes or other economically unproductive acts instead of the generation of generative economic activity. There also tends to be concentrations of ownership over specific plots of land that have proven to yield natural resources.

In recent years, the depletion of natural capital and attempts to move to sustainable development have been a major focus of development agencies. This is of particular concern in rainforest regions, which hold most of the Earth’s natural biodiversity – irreplaceable genetic natural capital. Conservation of natural resources is the major focus of natural capitalism, environmentalism, the ecology movement, and Green Parties. Some view this depletion as a major source of social unrest and conflicts in developing nations.Other information sources

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Why Does Earth’s Magnetic Field Flip?

Posted on February 26, 2008 by Rashid Faridi

Earth’s magnetic field has flipped many times over the last billion years, according to the geologic record. But only in the past decade have scientists developed and evolved a computer model to demonstrate how these reversals occur.

“We can see reversals in the rocks, but they don’t tell us how it happens,” said Gary Glatzmaier, an earth scientist and magnetic field expert at the University of California, Santa Cruz.

Based on a set of physics equations that describe what scientists believe are the forces that create and maintain the magnetic field, Glatzmaier and colleague Paul Roberts at the University of California, Los Angeles, created a computer model to simulate the conditions in the Earth’s interior.

The computer-generated magnetic field even reverses itself, allowing scientists to examine the process.

Computer Model

Scientists believe Earth’s magnetic field is generated deep inside our planet. There, the heat of the Earth’s solid inner core churns a liquid outer core composed of iron and nickel. The churning acts like convection, which generates electric currents and, as a result, a magnetic field.

This magnetic field shields most of the habited parts of our planet from charged particles that emanate from space, mainly from the sun. The field deflects the speeding particles toward Earth’s Poles.

Our planet’s magnetic field reverses about once every 200,000 years on average. However, the time between reversals is highly variable. The last time Earth’s magnetic field flipped was 780,000 years ago, according to the geologic record of Earth’s polarity.

The information is captured when molten lava erupts onto Earth’s crust and hardens, much in the way that iron filings on a piece of cardboard align themselves to the field of a magnet held beneath it.

Most scientists believe our planet’s magnetic field is sustained by what’s known as the geodynamo. The term describes the theoretical phenomenon believed to generate and maintain Earth’s magnetic field. However, there is no way to peer 4,000 miles (6,400 kilometers) into Earth’s center to observe the process in action.

That inability spurred Glatzmaier and Roberts to develop their computer model in 1995. Since then, they have continued to refine and evolve the model using ever more sophisticated and faster computers.

The model is essentially a set of equations that describe the physics of the geodynamo. The equations are continually solved, each solution advancing the clock forward about a week. At its longest stretch, the model ran the equivalent of 500,000 years, Glatzmaier said.

By studying the model, the scientists discovered that, as the geodynamo generates new magnetic fields, the new fields usually line up in the direction of the existing magnetic field.

“But once in a while a disturbance will twist the magnetic field in a different direction and induce a little bit of a pole reversal,” Glatzmaier said.

These bits of a pole reversal are referred to as instabilities. They constantly occur in the fluid flow of the core, tracking through it like little hurricanes, though at a much slower pace—about one degree of latitude per year.

Typically, instabilities are temporary. But on very rare occasions, conditions are favorable enough that the reversed polarity gets bigger and bigger as the original polarity decays. If this new polarity takes over the entire core, it causes a pole reversal.

“It’s a very complicated, chaotic system, and it has a life of its own,” Glatzmaier said.

Weak Spot

Peter Olson, a geophysicist at Johns Hopkins University in Baltimore, Maryland, said scientists can now pinpoint the core-mantle boundary where these instabilities in the magnetic field are happening.

One such disturbance Olson has been observing recently formed over the east-central Atlantic Ocean. Like a little hurricane, the anomaly swept toward the Caribbean and is moving up in the direction of North America.

“It’s a new one, a little thing,” Olson said. “Time will tell whether it develops into something significant. But it is here in the North Atlantic, moving towards the Pentagon. We can track it over the next couple of decades.”

Instabilities such as this, Olson added, are causing Earth’s magnetic field to weaken. Today the field is about 10 percent weaker than it was when German mathematician Carl Friedrich Gauss first began measuring it in 1845. Some scientists speculate the field is headed for a reversal.

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Iran to India Natural Gas Pipeline

Posted on February 25, 2008 by Rashid Faridi
Since the discovery of natural gas reserves in Iran’s South Pars fields in 1988, the Iranian government began increasing efforts to promote higher gas exports abroad. The prospects for profit are especially high in South Asian countries like India and Pakistan, where natural gas reserves are low and energy demand exceeds energy supply. In 1995, Pakistan and Iran signed a preliminary agreement for construction of a natural gas pipeline linking the Iranian South Pars natural gas field in the Persian Gulf with Karachi, Pakistan’s main industrial port located at the Arabian Sea. Iran later proposed an extension of the pipeline from Pakistan into India. Not only would Pakistan benefit from Iranian natural gas exports, but Pakistani territory would be used as a transit route to export natural gas to India. Initially, the Indian government was reluctant to enter into any agreement with Pakistan due to the historically tense relationship between the two neighbors. As an alternative, India suggested the development of a deep sea pipeline where no threat to security of resources could exist. At present, in 2000, Indian, Iranian, and Pakistani government officials continue to negotiate the possible routes, modes of transport, and geopolitics of the Iran to India natural gas pipeline. These negotiations indicate a significant shift in inter and intra-regional politics between the states. The potential for economic and developmental gain from natural gas will force India, Iran, and Pakistan to reassess their roles and policies in regional conflicts, like Kashmir, Afghanistan, and national security issues. Furthermore, potential economic collaboration and gain will also lead to a possible transformation of social and political discourse between the countries, perhaps even leading to mediation and resolution of regional conflicts.

 Description

THE PEACE PIPELINE:
IMPLICATIONS FOR CONFLICT RESOLUTION, FOREIGN POLICY, AND REGIONALISM

The exportation of natural gas from Iran to India through Pakistan is a venture which may change the face of regional politics in South Asia. It is a study in how economic collaboration possesses the power to engender as well as transform social and political discourse between countries. The Indian government speculated whether Pakistan could guarantee security for the flow of natural gas in the pipeline. Furthermore, Pakistan’s collaboration with Iran may foster conflict resolution as well. In the past, Iranian and Pakistani foreign policies have disagreed on the issues of Afghanistan and Shi’a-Sunni conflicts in the region. Thus, trade and the larger experience of economic globalization posesses the ability to exist as mediators in conflicts in the region and between regions.

Natural gas trade between India, Iran, and Pakistan challenges the geopolitical, historical, and strategic realities of the three countries and the general regions of the Mideast and Asia. In this way, the relationship between the pipeline venture and globalization is multidisciplinary. It is not characterized solely by economic factors, even though the current economic realities in Iran, India, and Pakistan do foreshadow the future necessity of economic collaboration. The realities of this case study are representative of the notion that multidisciplinary globalization is changing the face of regional politics and altering the social and political landscape of regions.

NEGOTIATING THE PIPELINE

Holding approximately 9 percent of the world’s total reserves, Iran is OPEC’s second largest producer of oil (Iran Background Information). Along with oil reserves, Iran contains the world’s second largest natural gas reserves “at an estimated 812 trillion cubic feet (Tcf)” (Ibid). While Iranian natural gas consumption is high, the country desperately needs to promote export markets for gas due to its faltering economy and to meet the demands of modernization. To meet these demands, Iran has targeted emerging regional markets like South Asia for natural gas exports.

Iran has proposed the export of natural gas from Iran to India since 1993. Alongside this proposal was the plan to export natural gas to Pakistan as well. The Iranian government proposed the construction of a pipeline from its South Pars fields in the Persian Gulf to Pakistan’s major cities of Karachi and Multan and then further onto Delhi, India.

The following map shows the pipeline’s main route. Starting from the left side of the map, the pipeline originates in Asaluyeh, Iran on the coast of the Persian Gulf near the Iranian South Pars fields. It travels to Pakistan through Khuzdar, with one section of it going on to Karachi on the Arabian Sea coast, and the main section traveling on to Multan, Pakistan. From Multan, the pipeline travels to Delhi, where it ends. At this point, India is free to consider and negotiate further domestic routing of the pipeline.

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