Tholeiitic basalts of Deccan large igneous province, India: An overview

Abstract

The Deccan large igneous province (DLIP) of Peninsular India is predominantly composed of tholeiitic basalts with a minor amount of alkaline, carbonatite, and silicic rocks. The tholeiitic basalts of DLIP are enriched in incompatible trace elements and divisible into low‐Ti basalts (TiO2 < 2.5; Ti/Y < 500) and high‐Ti basalts (TiO2 > 2.5; Ti/Y > 500). Despite variable total REE content, both low‐Ti and high‐Ti basalts exhibit almost similar geochemical patterns in the chondrite‐ and primitive‐ mantle‐normalized diagrams. The mantle potential temperature (Tp) of high‐Ti tholeiites estimated at Ca.1368°C, which is consistent with an ambient mantle temperature (1300–1400°C) whereas the Tp of low‐Ti tholeiites is around 1553°C, which indicates its derivation from the mantle plume axis. Extensive assimilation of the crustal components into the ascending plume have masked the nature and compositional characteristics of both high‐ and low‐Ti basalts. The low‐Ti basalts indicate significant contamination with crustal components than the high‐Ti basalts. The geochemical and isotopic compositions indicate the involvement of multiple mantle components. In general, the differentiated tholeiites of DLIP are the products of plume and depleted sections of the mantle with or without contributions from the continental crust. The main phase of Deccan magmatism intensely affected the atmosphere and hydrosphere, which was a possible trigger for the mass extinction event at the K–Pg boundary.

The Magmatic Architecture of Continental Flood Basalts I: Observations From the Deccan Traps

“…The Deccan Traps is a late Cretaceous-Paleogene continental flood basalt province covering more than 500,000 km 2 of peninsular India (Kale, Dole, et al, 2020;Krishnamurthy, 2020a, and references therein;Mahoney, 1988;Manu Prasanth et al, 2019;Verma & Khosla, 2019). The Deccan Traps mark the beginning of the Réunion hotspot track and are associated with partial melting due to the arrival of a deep mantle plume under the Indian subcontinent (presently beneath Réunion; e.g., Richards et al, 1989); see Peters et al (2017) for discussion of isotopic evidence).…”

Reactivity of Basaltic Minerals for CO2 Sequestration via In Situ Mineralization: A Review

“…They are present in the tholeiitic field of the TAS diagram and have moderate to high silica content. Tholeiitic basalts are commonly associated with mid-ocean ridges and continental flood basalt provinces [114][115][116].…”

Evolution of the Indian subcontinent: Introduction

“…Their results suggest a long‐lived thermal event possibly related to the input of radiogenic heat. Manu Prasanth, Hari , and Santosh (—this issue) provide an overview of the Deccan large igneous province (DLIP) of Peninsular India, predominantly composed of tholeiitic basalts with a minor amount of alkaline, carbonatite, and silicic rocks. The mineralogical and geochemical data suggest that these rocks were derived from a mantle plume with extensive assimilation of crustal components.…”