Petrology of the prehistoric lavas and dyke of the Barren Island, Andaman Sea, Indian ocean
DSpace at IIT Bombay
View Archive InfoField | Value | |
Title |
Petrology of the prehistoric lavas and dyke of the Barren Island, Andaman Sea, Indian ocean
|
|
Creator |
ALAM, MA
CHANDRASEKHARAM, D VASELLI, O CAPACCIONI, B MANETTI, P SANTO, PB |
|
Subject |
chemical classification
volcanic-rocks barren island lava flows dyke petrology sunda arc |
|
Description |
Although Barren Island (Andaman Sea, Indian Ocean) witnessed several volcanic eruptions during historic times, the eruptions that led to the formation of this volcanic island occurred mainly during prehistoric times. It is still active and currently in the fumarolic stage. Its volcanic evolution appears to be characterized by a constructive phase with the piling up of lava flows and scoria deposits and Strombolian activities, followed by a sudden collapse of the main cone. Deposits of a possible caldera-forming eruption were not recognized earlier. After a period of peri-calderic hydromagmatic activity, whose deposits presently mantle inner and outer caldera walls, a new phase of intra-calderic Vulcanian activities took place. A prominent dyke in the SE inner side of the caldera wall was recognized. Petrographically the lava flows and dyke are similar but they differ in their chemical composition (viz., SiO2, MgO, Ni, Cr) significantly. Similarity in major, minor and trace element composition (viz., K/La, K/Nb, K/Rb, K/Ti ratios) of these rocks together with Chondrite normalized trace element (Rb, Ba, Sr, P, Zr, Ti and Nb) and REE (La, Ce, Nd and Y) patterns of the Barren Island prehistoric lava flows and dyke and low-K lavas of Sunda Arc indicates that Barren Island must have evolved from a source similar to that of Sunda Arc lavas during the Quaternary Period.
|
|
Publisher |
INDIAN ACADEMY SCIENCES
|
|
Date |
2011-08-02T06:29:16Z
2011-12-26T12:53:44Z 2011-12-27T05:40:43Z 2011-08-02T06:29:16Z 2011-12-26T12:53:44Z 2011-12-27T05:40:43Z 2004 |
|
Type |
Article
|
|
Identifier |
PROCEEDINGS OF THE INDIAN ACADEMY OF SCIENCES-EARTH AND PLANETARY SCIENCES, 113(4), 715-721
0253-4126 http://dspace.library.iitb.ac.in/xmlui/handle/10054/8690 http://hdl.handle.net/10054/8690 |
|
Language |
en
|
|