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
Negi, B. S.
- Natural Root Grafting in Sal (Shorea robusta)
Authors
Source
Indian Forester, Vol 110, No 3 (1984), Pagination: 320-321Abstract
no abstract- Anatomy of Indian Bamboos Part I
Authors
Source
Indian Forester, Vol 86, No 12 (1960), Pagination: 719-727Abstract
Anatomical structure of epidermis of monocotyledons has often been of great practical value in identification. In the case of bamboos, epidermal studies have got special significance as floral characters are not readily available due to the flowering taking place only once in their life time. With a view to assess the diagnostic value of stem epidermis of Indian bamboos, six important species viz., Bambusa arundinacea Willd., B. Polymorpha Munro, B. vulgaris Schrad, Dendrocalamus membranaceus Munro, D. strictus Nees and Melocanna bambusoides Trin. have been investigated. The size, frequency, distribution and other characteristics of various epidermal structures useful in identification have been recorded and depicted. The exodermic epidermal appendages such as hairs and spines which commonly occur on the bamboo skin have also been studied and recorded.- Petrography and Tectonic Setting of the Andaman Ophioilite Suite With a Note on its Evolution
Authors
1 Atomic Minerals Division, Department of Atomic Energy, 1-1-153, Begumpet, Hyderabad 500 016, IN
2 Atomic Minerals Division, Department of Atomic Energy, West Block VII, R. K. Puram, New Delhi 110022, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 25, No 10 (1984), Pagination: 655-665Abstract
The Andaman ophiolite suite, consists of ultramafic to mafic plutonites, basic volcanics and chert beds. Ophiolites were emplaced as linear belts along major and deep 'seated N-S-trending fault zones in eugeosynclinal flysch series of the Port Blair Group. Ultramafic plutonites include dominant serpentinile and minor dunite, harzburgite and Tare pyroxenite, with the last three exhibiting different degrees of serpentinization. Among the mafic and related plutonites, olivine-gabbro and gabbro are dominant. A layered complex, comprising olivine-gabbro, gabbro, anorthositic gabbro and anortho- site. is recorded near Kodiaghat in South Andaman island.
Low grade metamorphic effects under the greenschist facies conditions and metasomatic alteration, of varying intensity culminating finally in near-total serpentinization together with high-temperature contact metamorphism are recorded.
A model involving partial melting of a CO2-Saturated upper mantle material of 'Spinel-peridotite at about 20 K bar pressure leading to the formation of an alkalic basalt that got separated and extruded first from a probable hot-spot within the Indian Ocean Plate is suggested. This was followed by the intrusion of ultramafics along deep seated N-S trending fault zones in the eugeosyncline involving vertical tectonics. The Andaman ophiolites were not involved in any obduction or large scale lateral migration, and hence may be considered as belonging to an autochthonous-type, in contrast to many on-land allochthonous ophiolites.