Chris D. Clark

TL;DR: The high-grade terranes of southern India are made up of four main tectonic units; from north to south these are a) the Salem Block, b) the Madurai Block, c) the Trivandrum Block, and d) the Nagercoil Block as discussed by the authors.

TL;DR: In this article, the authors show that coral reef classification accuracy can be improved by compensation for light attenuation in the water column and contextual editing to account for generic patterns of reef distribution.

Abstract: The Mozambique Ocean closed as Gondwana formed. Its suture has been identified in Madagascar (Betsimisaraka suture), but its continuation, into India, is controversial. The Palghat-Cauvery shear system appears an ideal candidate as it: (i) lies along strike of the Betsimisaraka suture in Gondwana; (ii) forms a high-pressure granulite belt; and (iii) separates crustal domains with different geological histories. However, existing age constraints have been used to suggest that the structure is Archaean/Palaeoproterozoic. Here we date metamorphic zircons using secondary ion mass spectrometry (535.0 ± 4.9 Ma) and monazites using electron probe micro-analysis (537 ± 9, 532 ± 8, 525 ± 10 Ma). No evidence for an earlier metamorphic event was found. The identification of Palghat-Cauvery high-pressure metamorphism as Cambrian, and recognition that it bounds crustal domains of contrasting origin, points to it being the southern continuation of the Betsimisaraka suture and southern margin of Neoproterozoic India.

TL;DR: A review of the academic literature and British Geological Survey mapping is employed to produce a "Glacial Map" and accompanying geographic information system (GIS) database, of features related to the last (Devensian) British Ice Sheet as discussed by the authors.

TL;DR: Yakymchuk et al. as mentioned in this paper presented the Th/U ratios in metamorphic zircon, which has been published in the Journal of Metamorphic Geology.