Monsoon rainfall and contrasting source rocks influenced sediment composition of peninsular basins along the east coast of India (western Bay of Bengal)

被引：16

作者：

Peketi, A. ^{[1
]}

Mazumdar, A. ^{[1
]}

Pillutla, S. P. K. ^{[1
]}

Rai, V. K. ^{[2
]}

Sawant, B. ^{[1
,3
]}

Chaitanya, A. V. S. ^{[1
]}

Krishna, Rama ^{[1
]}

机构：

[1] CSIR Natl Inst Oceanog, Panaji 403004, Goa, India

[2] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85287 USA

[3] CSIR NIO, Acad Sci & Innovat Res, Panaji, Goa, India

来源：

MARINE AND PETROLEUM GEOLOGY | 2020年 / 118卷

关键词：

Deccan basalts; Monsoon; Provenance; Weathering; Peninsular India; KRISHNA-GODAVARI BASIN; LATE QUATERNARY SEDIMENTS; ND ISOTOPIC COMPOSITION; DECCAN TRAP LAVAS; SOUTH CHINA SEA; SUMMER MONSOON; STRONTIUM ISOTOPES; CONTINENTAL-CRUST; MAJOR-ELEMENT; SR-ISOTOPE;

D O I：

10.1016/j.marpetgeo.2020.104433

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

The peninsular India is characterized by remarkable variation in lithological composition as well as contrasting rainfall distribution patterns. The erosional and weathering history of these source rocks along with monsoonal changes are archived in sediments deposited in the basins along the east of coast of India. Here, we present a 60 ky record of Sr-Nd isotope ratios coupled with major elemental compositions of a sediment core off Krishna-Godavari (K-G) basin, western Bay of Bengal. The marked temporal variation in Sr-87/Sr-86, epsilon Nd, and Mg/Al ratios are attributed to the changes in relative contribution of sediments from the Deccan Basalts (DcB) and Archean-Proterozoic gneissic complexes (APGC). The enhanced contribution of APGC associated with an increase in monsoon precipitation may be attributed to heightened erosion of the granitic gneissic rocks. On the other hand, a close correlation of Sr-87/Sr-86 ratios with Rb/Sr ratio, delta O-18(G-ruber), and CIA profiles indicate the possible influence of weathering intensity on the sediment composition.

引用

页数：10

共 126 条

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