Earth News This Week

Saturday, September 1, 2007

Modern Humans in India

Modern Humans Lived in India Earlier Than Thought, Study Finds

By Chris Dolmetsch

July 5 (Bloomberg) -- Remains of stone tools found amid ash deposits in India from a volcanic eruption 74,000 years ago show that modern humans were living there earlier than scientists had previously thought, according to a study to be published in tomorrow's edition of the journal Science.

The Youngest Toba Tuff eruption in Indonesia, the largest volcanic event of the past 2 million years, blanketed an area from the South China Sea to the Arabian Sea with ash. Scientists had theorized that the blast produced a ``volcanic winter'' that lowered global temperatures, killing plants and animals and keeping humans from leaving Africa more than 60,000 years ago.

Study author Michael Petraglia, a University of Cambridge lecturer, and colleagues found tool fragments from soil both above and below a deposit of Toba Tuff ash, showing that humans were already in India at the time and survived the blast.

``This is some of the earliest evidence for the spread of modern humans out of Africa towards Australia,'' Petraglia said in a telephone interview from New York.

Petraglia and colleagues including Ravi Korisettar of Karnatak University in Dharwad, India, found 215 artifacts under a 2.55-meter (8.4-foot) thick ash deposit near Jwalapuram, in the Jurreru River valley of southern India, and 276 more relics above the layer.

Limestone, Quartzite Fragments

The study says the relics, made of limestone, quartzite, chert and other minerals, are likely from a variety of stone tools from the Indian Middle Paleolithic era that lasted from about 150,000 to 38,000 B.C.

Yet the characteristics of the artifacts are more typical of the African Middle Stone Age that ended about 40,000 years ago than they are of younger artifacts found elsewhere in Europe and Asia, the study says. That finding suggests that modern humans had migrated out of Africa and were already in southern India when the Toba Tuff eruption blanketed the region in ash.

``It will be very much debated,'' Petraglia said. ``There are people that are wedded to their theories and won't like it at all, and there are others who will welcome our study because this part of the world is very understudied.''

The research was funded by the Swindon, U.K.-based Natural Environment Research Council and its Arts and Humanities Research Council Oxford Radiocarbon Accelerator Dating Service, the Berkeley, California-based Leakey Foundation, the McDonald Institute for Archaeological Research, the Australian Research Council and Queens College in Cambridge.

Murder in the field

University of Colorado Geology Graduate student murdered

On June 26, 2007 newlywed Alyssa Heberton-Morimoto, a 24-year-old geology graduate student at the University of Colorado at Denver and an intern with the Colorado Geological Survey, was murdered while doing field work.

Heberton-Morimoto had been out in the remote Pike-San Isabel National Forest in Park County, Colo., mapping the geology of a ridge in the forest with her advisor, Karen Houck, a geologist. According to an affidavit, the two split up shortly before lunch on June 26, with Heberton-Morimoto taking their Jeep along one side of the ridge and Houck walking along the other side. Houck radioed Heberton-Morimoto that she would be late meeting her for lunch. About five minutes later, according to Houck, she received a frantic call from Heberton-Morimoto, who was screaming “Help me, Help me!” Houck set off immediately, locating her student’s belongings and the Jeep (with no car keys) at the agreed-upon meeting point about 20 minutes later. There was no sign of Heberton-Morimoto or her radio, according to a June 28 Denver Post article.

Houck saw a truck parked at a nearby campground and flagged down its owner, asking for a ride to find cell phone reception to call for help. About 10 hours later, authorities found Heberton-Morimoto’s body in a creek 100 meters from the campsite where her Jeep was parked, with a military-style web belt wrapped around her neck, according to the Denver Post article.

In a creepy twist, the man who gave Houck a ride to get help has been charged with Heberton-Morimoto’s murder. Robert Amos, also known as Dennis Lee Cook, is a 44-year-old parolee who was imprisoned for 19 years on a murder conviction and has faced several other attempted murder investigations and charges. Cook has been out of prison since 2001. He has been charged with first-degree murder in this case, in addition to several other counts, including being a habitual criminal. Authorities still have not released a motive for the slaying, according to a July 3 Denver Post article. Amos had apparently been living in the campground for a few weeks, and had alarmed other campers with his odd behavior.

Vince Matthews, director of the Colorado Geological Survey, said on June 28 that the survey emphasizes safety and defensive tactics for its mapping employees, but the focus has always been on wildlife. Since the murder, the survey has reiterated its directive that all field workers work in close pairs.

Friday, August 31, 2007

Groundwater on Mars

Mars definitely had GW

Coupled Ferric Oxides and Sulfates on the Martian Surface



The Mars Exploration Rover (MER), Opportunity, showed that layered sulfate deposits in Meridiani Planum formed during a period of rising acidic ground water. Crystalline hematite spherules formed in the deposits as a consequence of aqueous alteration and were concentrated on the surface as a lag deposit as wind eroded the softer sulfate rocks. On the basis of Mars Express Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité (OMEGA) orbital data, we demonstrate that crystalline hematite deposits are associated with layered sulfates in other areas on Mars, implying that Meridiani-like ground water systems were indeed widespread and representative of an extensive acid sulfate aqueous system.


Science 31 August 2007:
Vol. 317. no. 5842, pp. 1206 - 1210

Glacier retreat: Gangotri 83 ft/yr

Gangotri glacier receding by 83 feet every year

Global warming has severely affected Himalayan glaciers and the Gangotri glacier, the source of river Ganga, was shrinking by 83 feet every year.

Minister for Science and Technology Kapil Sibal said in the Lok Sabha the Geological Survey of India has been conducting studies on the recession of the Gangotri glacier since 1935.

'The rate of shrinking of 30.2-km long Gangotri Glacier in the last three decades has been found to be more than the rate during the earlier decades,' Sibal said.

'The average rate of recession has been computed... and the 2001 satellite imagery and the results shows that average recession for this period (last three decades) is about 83 feet/year,' he said.

Sibal, however, expressed optimism over the future of this process and the fate of the glacier.

'Although the shrinking of the Gangotri Glacier is a matter of concern, the prospect of disappearance of the glacier does not exist,' the minister added.

Earlier this year, the Intergovernmental Panel on Climate Change, a conglomerate of scientists and climate experts from across the globe, had portrayed a negative future for the globe in the wake of global warming.

It has said that India will be affected severely due to climate change. The glaciers will recede, the ocean will swell and cities and mangroves near the coast will face the threat of getting submerged.

Orchids are Cretaceous in age; not Tertiary

Caught in amber


Since Darwin's time, biologists have been fascinated by the intimate relationship between orchids and their pollinators. The antiquity of this relationship is demonstrated by the remarkable fossil preserved in 15–20-million-year-old amber from the Dominican Republic, a worker stingless bee carries an orchid pollinarium. The pollinarium is the male reproductive structure, transferred as a single unit during pollination, complete with a mass of pollen grains. The find, surprisingly, is the first definitive fossil from the Orchidaceae family. The pollinarium's morphology locates the plant in the subtribe Goodyerinae. By combining this information with dates from related fossil plants, a new calibration of the molecular phylogeny of the Orchidaceae has been obtained. The analysis rejects the common assumption of a recent (Tertiary) origin for orchids, and suggests, instead, that they originated during the Late Cretaceous, 80 million years ago.

These results have been reported by Santiago R. Ramírez of the Harvard University's Museum of Comparative Zoology, 26 Oxford St. Cambridge, MA 02138 USA.

LetterDating the origin of the Orchidaceae from a fossil orchid with its pollinator

Santiago R. Ramírez, Barbara Gravendeel, Rodrigo B. Singer, Charles R. Marshall & Naomi E. Pierce

doi:10.1038/Nature Volume 448 Number 7157 969-1080

First paragraph

Wednesday, August 29, 2007

Bailadila Iron: which state in India?

Bailadila hills, have India's largest iron ore stocks

Chhattisgarh stood third in overall production of mineral wealth in India during the fiscal year that ended March 2007.

The state earned revenue of Rs.8.32 billion during the fiscal year from the production of iron ore, coal and bauxite, the Mines and Geology department said.

It said the main focus during 2007-08 would be on finding new deposits of coal, iron ore, bauxite and limestone.

Tests of soil samples have indicated uranium reserves in Gotulmuta area in Durg district and in the basins of river Indravati in the state's southern region.

In 2006-07, the Mines and Geology department collected 5,288 samples of soil for advanced laboratory tests from a total of 3,212 sq km area that was surveyed.

Besides, encouraging survey inputs have come from Raipur and Kanker districts about gold reserves.

Chhattisgarh, having about 18 percent of country's coal deposits and 20-22 percent of world's finest quality iron ore, is planning to increase iron ore production from the extreme southern Dantewada district's Bailadila hills.

The Bailadila hilly range, which has India's largest iron ore stocks, is divided into 14 deposits. Three of them are being used by the public sector major National Mineral Development Corp Ltd (NMDC) for domestic supply besides exports to China, Japan and other Asian nations.

Volcansim in Arunachal Pradesh

Fumaroles erupt in Arunachal Pradesh

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By Syed Zarir Hussain. India, 10:31 AM IST 27-8-2007

Authorities in Arunachal Pradesh have sounded an alert after lava and hot gas clouds began erupting from the side of a hill, officials said Tuesday.

A government spokesman said a rare geological occurrence was reported from a hill slope near Kimin village, about 75 km north of state capital Itanagar.

'Residents first witnessed a fire in the hill and afterwards it began spewing ash and sending debris down its slopes that appears like typical molten magma of a volcano,' Bidol Tayeng, district magistrate of Papum Pare, told IANS.

The phenomenon was first reported Aug 21 from the area where there was no human habitation. The nearest human settlement is located about a kilometre from the hill slope.

'The debris found in the area was of different colours like black, green and brown. Some of the substances also appear like glass, besides burnt bricks and rocks,' the magistrate said.

'Such was the intensity of the heat from the flying debris that a high tension power pole near the site of the occurrence melted, resulting in power disruption.'

Residents in the area are panicking, with authorities sealing the area by deploying police and preventing people from going near the hill.

'The site is lying dormant but not extinct, as the area continues to emit smoke and gas and also the nearby earth was found to be very hot,' said N. Nyori, a local administrator in Kimin.

Experts from the Geological Survey of India (GSI) have visited the area and collected samples for laboratory tests at their headquarters in Kolkata.

'This is some sort of a fumerolic activity which could be the beginning of some activity inside the earth. The molten magma has probably oozed out owing to rise in temperature of at least 1,000 degrees centigrade,' a GSI scientist said requesting not to be named.

The laboratory test report is expected by the weekend.

India's northeastern region is considered by seismologists to be the sixth most quake prone belt in the world with Arunachal Pradesh - bordering China and Myanmar - listed in the seismic zone V category.

'Evidence of volcanic eruptions some millions of years back has been found in a village named Lichi, about 15 km from the present eruption site. However, there are no historical remains of any volcanic mountain - either extinct, dormant or active in the region,' the scientist said.

GSI experts are camping in the area to observe the rare occurrence and have asked authorities not to allow locals to go near the site.

'There has been no fresh oozing since Aug 21 although more such occurrences cannot be ruled out,' the scientist said.

River Sand: Any alternatives?

Marine Sand

Shareef of GSI Marine Wing Mangalore has these suggestions in his Current Science article

Offshore sand: An alternative?
N. M. Shareef

Sand is an essential material for construction purpose, and there is no alternative to it till date. The demand for constructiongrade sand in our country is increasing day by day due to the boom in construction fuelled by economic prosperity. Such a huge demand is pushing people to dig into the deeper bosoms of the traditional sources of sand, like riverbeds, lagoons, beach dunes, etc. exerting severe stress on these sources. Unmindful and indiscriminate sand mining not only depletes these natural resources, but also creates environmental problems. The environmental impact of unscientific and unscrupulous exploitation of these precious natural resources is well documented in the scientific literature. The impact of such exploitation is of late being felt by the people who are living inthe vicinity of the mining areas. The administration and civil society seem to be callous in their approach to such issues and remain contented by satiating their wants without thinking about the planet earth, which they owe to the next generation.

Consequences of riverbed sand mining include depletion of groundwater, saline intrusion, destruction of agricultural land, loss of employment to farm workers, threats to livelihood, destruction of ecosystems and even human rights violation. Uncontrolled sand mining from the riverbed leads to the destruction of the entire river system. Sand acts like a sponge, which helps in recharging the water table. Once this layer is removed, the hydrodynamics of the river gets disturbed and affects the velocity of water flow. This also enhances the penetration of sunlight deep into the soil, which aggravates the groundwater evaporation. Excessive instream sand and gravel mining lower the river bottom, which distorts the flow regime leading to the river bank erosion. As the trucks race to the middle of the river to collect sand, a bit of the riverbed dies every day. Such destruction destroys the entire habitat in the area. Depletion of the sand in the stream bed and along the coastal areas causes deepening of rivers and estuaries and enlargement of river mouth and coastal inlets. The direct consequences of this is the easy intrusion of saline, water especially during high tides. Once the saline water intrudes into the stream, it destroys the ecosystem. Widening of the river mouths and tidal inlets may expose the entire area to become vulnerable to storm surges and cyclones.

The booming construction industry however requires sand, as there is no alternative to substitute it. The time has come to explore an alternate to this traditional source, and offshore sand gives a ray of hope. Whenever there is a mention about offshore sand, people have a misconception that its refers to the beach and near beach sand. No doubt, these areas are ecologically highly sensitive and any disturbance to it will have serious implications on the beach and its processes.

Sand occurring beyond 25 m water depth and beyond the territorial waters seems to be the answer to the imperatives. The Marine Wing of the Geological Survey of India has already established the reserves of several million tonnes of construction-grade sand in the offshore of Kerala coast (Marine Wing Newsl., Geological Survey of India, vol. xx, No. 1 & 2, March–September 2006). Such a huge resource, if exploited commercially without destroying the environment, will be a viable substitute for the over-exploited traditional sources of sand. Offshore sand mining will have minimum effect on the physical environment of the sea as it does not affect the wave dynamics and beach profile. Mining them will have minimum impact on the beach process because there is no cross transportation either from the beach to these deposits or vice versa. Also the said resource is beyond 30 km from the shoreline. These sand bodies are remnants of submerged strand line deposits left behind when thesea moved landward during the last transgression. Similarly, the shelf break in the west coast is wider compared to that in the east coast and the gradient of the shelf is roughly 1 m ´ 500–1000 m. This offshore sand as we understand, is naked sand without any overburden and its extraction will not require any removal of the overburden which may again agitate the sea bottom. The main attraction of these sand bodies is that they comprise all the grades of sand, both for construction as well as for the glass industry.

Although the impact of offshore sand mining on the physical environment of the sea will be minimal, its impact on the biological environment has to be studied in detail before taking any decision. Since sand mining at these depths has not been carried out before, provision must be made to enable scientific monitoring and gathering of information. Specific impact assessment should be done for each area. Understanding the impact of any aggression on the planet earth is essential for sustainable development.

N. M. SHAREEF
Geological Survey of India,
Marine Wing,
Mangalore 575 001, India
e-mail: Shareef_n123@rediffmail.com

Uranium in Ladakh Batholith

Kumaon Geologist discovers uranium in the Ladakh region


Uranium–thorium-rich zircon in a granitoid dyke along the Shyok Suture Zone, Nubra–Shyok River Valley, Northern Ladakh, India


Rajeev Upadhyay


Scientists have for the first time found uranium in “exceptionally high concentration” in Ladakh, the icy Himalayan region in Jammu and Kashmir that has strategic significance for India.

Samples of rocks analysed in a German laboratory have revealed uranium content to be as high as 5.36 per cent compared to around 0.1 per cent or less in ores present elsewhere in the country.

India badly needs uranium to fuel its nuclear power plants and the proposed India-US nuclear deal is all about importing it. The Ladakh find may cheer those opposed to the deal even though detailed exploration and mining may take years.

The Ladakh block lies between the Indian plate in the south and the Asian plate in the north and is bounded by the “Indus and the Shyok suture zones”. Collision between the two plates 50-60 million years ago formed the Himalayas.

The earth’s crust that got crushed and melted during collision and pierced the surface, cooled and solidified becoming “magmatic” rocks dotting what geologists call the Ladakh “batholith”. It is in these rocks that uranium is found.

“The presently recorded uranium rich zircons from young magmatic intrusions of the Shyok suture zone and associated sequences is the first record from these remote regions,” said Rajeev Upadhyay, a geologist at Kumaon University in Nainital.

“In geological terms, these uranium-bearing magmatic rocks exposed in Ladakh are very young (between 100 million and 25 million years old),” he said.

Other uranium rich rocks in India such as in Andhra Pradesh, Chhattisgarh, Jharkhand and Rajasthan are very old geological terrains known as the Precambrian (2,500-3,000 million years old), he said.

For his study, reported in the journal Current Science, Upadhyay took samples from thick exposed granite from a place north of Udmaru village in Leh district. The village in the Nubra-Shyok River Valley is situated on a volcanic rock formation known as the Shyok Volcanics.

The samples of rock mineral (zircon) were analysed at the isotope laboratory of the University of Tuebingen in Germany where he had gone under the Alexander von Humboldt Fellowship.

“Geochemical analysis of the separated zircon grains showed exceptionally high concentration of both uranium (0.31 - 5.36 per cent) and thorium (0.76 - 1.43 per cent),” said Upadhyay. He added that the study is preliminary and “detailed work is in progress”. According to Upadhyay, uranium-bearing magmatic rocks are located all along Kohistan, Ladakh and southern Tibet (from east to west). “However, contents of uranium may differ from place to place,” he said.

Officials of the atomic minerals division under the Department of Atomic Energy (DAE) did not reply to questions about the significance of this new find or whether the Ladakh uranium could augment India’s reserves.

The total established uranium resources of the country so far (in the form of uranium oxide or yellow cake) are 94,000 tonnes. The majority of these resources, according to DAE, occur in three “provinces”: Singhbhum in the east, Mahadek in the northeast and Cuddapah in the south.

The low uranium content in ores, however, makes mined uranium in India expensive compared to that in Australia whose ores contain as much as 15 per cent uranium.

Satellite image of Greece fire


Natural Hazards >> Fires >> Fires in Greece
Fires in Greece Image. Caption explains image. Click here to view high-resolution version (1001.36KB)
Image Acquired: August 26, 2007

Fires in Greece

Deadly wildfires in southern Greece wafted thick clouds of smoke over the Ionian Sea and southward to the Mediterranean in late August 2007. This image of Greece was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on August 26, and places where MODIS detected actively burning fires are outlined in red. A line of fires stretches along the western coast of Greece’s Peloponnesus Peninsula. To the northeast, a large fire is casting a plume of smoke over Athens.

According to news reports from the British Broadcasting Corporation (BBC), at least 60 people had been killed by the fires as of August 27. Hundreds of homes had been burned and thousands had to evacuate. The government suspects that the fires were caused by arson, and it has declared a national emergency to deal with the situation.

The large image provided above has a spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response Team provides twice-daily images of the region in additional resolutions and formats, including an infrared-enhanced version that highlights burn scars.

NASA image courtesy the MODIS Rapid Response Team, Goddard Space Flight Center