Research is elitist, exclusive, discriminatory, and at the highest levels of outstanding quality.
Gautam Radhakrishna Desiraju
An incisive analysis of the malaise in Indian science by the veteran scientist Gautam Radhakrishna Desiraju in Nature India May 1, 2008. Read it.
Wednesday, May 7, 2008
Ailing science; ageing scientists: India in the dumps
Monday, May 5, 2008
Mis-match in ages from different dating techniques
There has been a lot of discussion in journals regarding the mismatch in the ages that are turned out by Ar-Ar dating, vis-a-vis U-Pb dating etc. The recent Letter to the Editor in Nature Geosciences (May 2008, p282, vol 1) by Heiko Pälike, University of Southampton, National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK
and Frits Hilgen, Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands puts the matter in perspective. Here is an extract of that article entitled "Rock clock synchronization". "The need for much improved knowledge of the durations and ages of climatic and geological events, such as the Palaeocene–Eocene Thermal Maximum (~55 million years ago), has become urgent within the Earth science and climate modelling communities. The exact dating and timing of fluxes into and out of the marine carbon reservoir can differentiate between competing hypotheses of climatic change. Highly detailed reconstructions of the Earth’s history allow us to assess whether past climatic change can be used as an analogue for the current and future change of ocean acidification and climate.
The Earthtime project is an international effort with the goal to further this quest for a well-calibrated and stable timescale that will allow more precise dating of rock layers and minerals. Radioisotopic dating methods have small but significant errors that hinder our ability to assess geologically short-lived climate events. For instance, the most widely used method for the Cenozoic era is 40Ar/39Ar, which has an error of up to 2.5% and few tie points of known age. Yet, over the last two decades much progress has been made in exploiting the imprint of the Earth’s orbital variations in palaeoclimatic records. This has dramatically increased the potential age resolution of approaches like cycle-counting and pattern matching, to less than 40,000 years throughout much of Cenozoic time (the past ~66 million years).
Unfortunately, there have been a number of inconsistencies and discrepancies between ages and durations derived from radioisotopic and astronomical dating. What is now needed is a more systematic and coordinated approach to provide a detailed intercalibration of radioisotopic clocks (U–Pb, Ar–Ar methods), the rock standards that are used for these methods, and geological tie-points with astronomical ages. At the same time, Cenozoic palaeoclimatic compilations need to be improved by closing existing gaps, verifying data from single sites and supplementing the database of magneto- and biostratigraphy so we can improve the accuracy of existing age calibrations.
In particular, a major advance towards a fully astronomically calibrated geological timescale needs to be accomplished in the middle Eocene epoch (~40 to 50 million years). Very few suitable sections have been acquired so far for this period, presumably because the calcite compensation depth was very shallow during this time, which would have prevented the preservation of carbonate material in the deep-ocean marine sediments. The Earthtime projects are open community efforts aimed at improving intercalibration between astronomical and radioisotope dating methods by finnding ash layers that can be dated with radioisotopes within astronomically age-calibrated sections. The immediate aim is to arrive at a highly accurate and stable Cenozoic timescale."
This paper in Science also deals with the same issue
and Frits Hilgen, Department of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, The Netherlands puts the matter in perspective. Here is an extract of that article entitled "Rock clock synchronization". "The need for much improved knowledge of the durations and ages of climatic and geological events, such as the Palaeocene–Eocene Thermal Maximum (~55 million years ago), has become urgent within the Earth science and climate modelling communities. The exact dating and timing of fluxes into and out of the marine carbon reservoir can differentiate between competing hypotheses of climatic change. Highly detailed reconstructions of the Earth’s history allow us to assess whether past climatic change can be used as an analogue for the current and future change of ocean acidification and climate.
The Earthtime project is an international effort with the goal to further this quest for a well-calibrated and stable timescale that will allow more precise dating of rock layers and minerals. Radioisotopic dating methods have small but significant errors that hinder our ability to assess geologically short-lived climate events. For instance, the most widely used method for the Cenozoic era is 40Ar/39Ar, which has an error of up to 2.5% and few tie points of known age. Yet, over the last two decades much progress has been made in exploiting the imprint of the Earth’s orbital variations in palaeoclimatic records. This has dramatically increased the potential age resolution of approaches like cycle-counting and pattern matching, to less than 40,000 years throughout much of Cenozoic time (the past ~66 million years).
Unfortunately, there have been a number of inconsistencies and discrepancies between ages and durations derived from radioisotopic and astronomical dating. What is now needed is a more systematic and coordinated approach to provide a detailed intercalibration of radioisotopic clocks (U–Pb, Ar–Ar methods), the rock standards that are used for these methods, and geological tie-points with astronomical ages. At the same time, Cenozoic palaeoclimatic compilations need to be improved by closing existing gaps, verifying data from single sites and supplementing the database of magneto- and biostratigraphy so we can improve the accuracy of existing age calibrations.
In particular, a major advance towards a fully astronomically calibrated geological timescale needs to be accomplished in the middle Eocene epoch (~40 to 50 million years). Very few suitable sections have been acquired so far for this period, presumably because the calcite compensation depth was very shallow during this time, which would have prevented the preservation of carbonate material in the deep-ocean marine sediments. The Earthtime projects are open community efforts aimed at improving intercalibration between astronomical and radioisotope dating methods by finnding ash layers that can be dated with radioisotopes within astronomically age-calibrated sections. The immediate aim is to arrive at a highly accurate and stable Cenozoic timescale."
This paper in Science also deals with the same issue
Oil and gas in Deccan Traps
ONGC strikes petroleum in Deccan Traps
The Times of India, on 1st May 2008, reported that the ONGC has struck oil and gas in the Deccan Traps. This is sure to be a path-breaking discovery, says the report by Rajeev Jayaswal. This comes in the wake of its discoveries of gas in Kunjaban-3 well in north Agarthala in Tripura, and oil in the Karjan-9 well in the Halisa field of Gujrat. The report goes on to say that India can become the top oil-producing nation, if the Trap oil and gas is successfully exploited. A reserve of about 30 billion tons is estimated in these Cretaceous rock formations.
The Mesozoic sediments below the Deccan Traps are highly prospective, the report cites an expert. Geophysical surveys for the oil below the traps were done by the National Geophysical Research Institute (NGRI) Hyderabad and the Directorate General of Hydrocarbons. They found sub-trappean Mesozoic to Gondwana age sediments with a maximum thickness of three kilometers.
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