A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Ranga Rao, A.
- On the Krol Nappe Hypothesis
Authors
1 Oil & Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 9, No 2 (1968), Pagination: 153-158Abstract
Geological mapping by the author in parts of Garhwal and Punjab Himalaya, in the areas between Nayar and Sutlej rivers in the south, and between Bhagirathi and Sutlej rivers in the north, revealed that the Krol belt rocks are autochthonous sediments deposited on a floor of Simla slate - Deoban group, and are not allochthonous as interpreted by Auden. The various field evidences in support of this view are cited.
- New Mammals from Murree (Kalakot Zone) of the Himalayan Foot Hills Near Kalakot, Jammu & Kashmir State, India
Authors
1 Oil & Natural Gas Commission, Dehra Dun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 12, No 2 (1971), Pagination: 125-134Abstract
A new genus, including two species, of the Artiodactyl family (?) Choeropotamidae from the Murree group, is described. These are the first mammalian fossils known from the Murree outcropping within the present day limits of Indian territory.- Magnetic Polarity Stratigraphy and Vertebrate Palaeontology of the Upper Siwalik Subgroup of Jammu Hills, India
Authors
1 Oil and Natural Gas Commission, Dehradun, IN
2 National Geophysical Research Institute, Hyderabad, IN
3 Wadia Institute of Himalayan Geology, Dehradun, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 31, No 4 (1988), Pagination: 361-385Abstract
Magnetic polarity stratigraphy of Upper Siwalik Subgroup, Jammu Hills was worked out based on partially demagnetized data from 208 sites in three sections: Parmandal-Utterbeni, Nagrota-Jammu and Balli. One/two bentonitized tuff horizons occur close to the base of a long reversed polarity zone associated with Pinjor age fossils. Fisson track dates of 2.8±0.56 m.y. and 2.31±0.54 m.y. have been obtained on the zircon phenocrysts from these tuffs. These data permit correlation of our magnetic stratigraphy with the standard magnetic polarity time scale. The longest sampled section spans the interval from 4.92 to 0.22 m.y. This dating places the lower part of Upper Siwalik in the early Pliocene.
In the sampled parts of the sections, the magnetic polarity zonation establishes 16 magnetozones in Parmandal-Utterbeni, 13 in Nagrota and one in Balli. Individual magnetic transitions can be correlated over a lateral distance of 62 km and these provide time lines for correlation of lithology from one section to the other.
Estimated rates of sedimentation indicate rates varying from 0-45 m to 0.71 m/l000 years for Gilbert and Gauss epochs, while a decreased rate varying from 0.21 m to 0.37 m/l000 years is indicated during the Matuyama epoch.
The ]ast folding event of Suruin-Mastgarh anticline is not older than 0.22 m.y. However, the decrease in the rate of sedimentation during post Gauss time could possibly be due to an earlier period of deformation.
A significant change in fauna near the Gauss-Matuyama boundary is observed by the appearance of Equus and cervids with antlers and by the absence of Hipparion. We correlate this boundary with the Tatrot-Pinjor faunal boundary, No change either in lithology or in the vertebrate fauna is observed at the Pliocene-Pleistocene boundary if it is to be placed at the top of the Olduvai Normal Subchron.
- Neogene-Quaternary Boundary in the Siwalik of Northwest Himalayan Foothills, India
Authors
1 Oil and Natural Gas Commission, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 33, No 2 (1989), Pagination: 95-103Abstract
Magnetic Polarity stratigraphy of the Upper Siwalik has been worked out along four traverses on the Surin-Mastgarh anticline, Jammu and Kashmir State. Fission-track dating of the bentonite beds allows correlation to the accepted magnetostratigraphic scale and identification of the Olduvai Normal Subchron in the Upper Siwalik sections.
The Vrica section, Italy, is now selected as the Pliocene-Pleistocene Boundary stratotype and the Pliocene-Pleistocene boundary is fixed above the Olduvai at 1.64 Ma, In the Upper Siwalik, at 1.64 Ma, there is no change either in the mammalian fauna or in lithology and life and sedimentation appears to have continued without any change. On the otherhand, a faunal change occurs at the Gauss-Matuyama transition dated at 2.48 Ma which is correlated to Tatrot-Pinjor faunal boundary. It is, therefore, suggested here that it is more practical to make the Pliocene-Pleistocene Boundary in the continental Siwalik to coincide with the base of Pinjor faunal boundary.