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John Kurian, P.
- Gravity Bases Established by Cochin University of Science and Technology (CUSAT) over Parts of Northern Kerala
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Authors
Affiliations
1 Department of Marine Geology and Geophysics, Cochin University of Science and Technology, Cochin - 682 016, IN
2 Department of Geophysics, Osmania University, Hyderabad - 500 007, IN
1 Department of Marine Geology and Geophysics, Cochin University of Science and Technology, Cochin - 682 016, IN
2 Department of Geophysics, Osmania University, Hyderabad - 500 007, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 51, No 3 (1998), Pagination: 393-398Abstract
A network of 30 gravity base stations have been established. The dynamic drift curves show an average drift rate of less than 0.006 mgal/min. The observed gravity values have repeatability of 0.08 mgal, and can be used for regional gravity surveys.Keywords
Geophysics, Gravity Base Staions, Kerala.
- Interpretation of Gravity Field Over the Perinthatta Anorthosite, Northern Kerala
Abstract Views :186 |
PDF Views:3
Authors
Affiliations
1 Department of Marine Geology and Geophysics, Cochin University of Science and Technology, Cochin - 682 016, IN
2 Department of Geophysics, Osmania University, Hyderabad - 500 007, IN
1 Department of Marine Geology and Geophysics, Cochin University of Science and Technology, Cochin - 682 016, IN
2 Department of Geophysics, Osmania University, Hyderabad - 500 007, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 54, No 5 (1999), Pagination: 483-490Abstract
Gravity surveys have been carried out over the Perinthatta anorthosite and the adjoining areas and the results are discussed. The Bouguer anomaly map reveals the absence of any conspicuous gravity anomaly corresponding to the pluton and thus precludes the existence of larger mafic portions of the pluton in the immediate subsurface region. The residual gravity map obtained by regional-residual separation method shows a minor positive gravity field of irregular shape with localised highs of 6 - 12 mgal within and around the anorthosite body. TWo-dimensional gravity interpretation of profiles across the pluton suggests subjacent nature and lensoid shape for the anorthosite which is underlain by small isolated cylindrical bodies (≃ 2.5 km diameter) of higher density (2.9 gm/cc) extending 3 - 7 km downwards. These cylindrical bodies are inferred as either the mafic/oxide rich portions of the pluton sagged down during crystallization or the individual feeders of the plagioclase-rich mushes, which coalesced in the upper crust to give rise to the massif.Keywords
Geophysics, Gravity, Anorthosite, Structure, Perinthatta, Kerala.- Morphology of the Two Unnamed Seamounts in the Arabian Basin and their Probable Tectonic Implications
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Authors
Affiliations
1 National Centre for Polar and Ocean Research, Vasco da Gama, Goa 403 804, IN
2 School of Earth, Ocean and Atmospheric Sciences, Goa University, Taleigao Plateau, Goa 403 206, IN
1 National Centre for Polar and Ocean Research, Vasco da Gama, Goa 403 804, IN
2 School of Earth, Ocean and Atmospheric Sciences, Goa University, Taleigao Plateau, Goa 403 206, IN
Source
Current Science, Vol 118, No 7 (2020), Pagination: 1118-1123Abstract
Newly acquired high resolution multibeam bathymetry data collected from Eastern Arabian Sea show the presence of two distinct, isolated seamounts (~27 km apart) in the flat Arabian Basin, west of Laccadive– Chagos Ridge. The seamount S1 with a relief of 1980 m from the adjacent seafloor has a linear ridge-like shape with NNE–SSW trend and is associated with craters and knolls near its base. Seamount S2 with a relief of 1830 m is conical in shape with steep slopes. Seismic characteristics imply that these two seamounts are extrusive volcanic features covered by thick pile of sediments along the flanks. The evolutionary history of the Arabian Basin and the tectonic fabric of the study area suggest that emplacement of the identified seamounts might be due to the Réunion hotspot volcanism.Keywords
Morphology, Multibeam Bathymetry, Réunion Hotspot Volcanism, Seamounts.Full Text
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