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The Elan Bank microcontinent was separated from East India during the Early Cretaceous break-up. The crustal architecture and rifting geometry of East India and the Elan Bank margins document that the early break-up between India and Antarctica was initiated in the eastern portions of the Cauvery and Krishna–Godavari rift zones, and in the southern portion of Elan Bank. However, the westwards break-up propagation along the Krishna–Godavari Rift Zone continued even after the break-up in the overstepping portion of the Cauvery Rift Zone. Eventually, the western propagating end of the Krishna–Godavari Rift Zone became hard-linked with the failed western portion of the Cauvery Rift Zone by the dextral Coromandel transfer fault zone. Consequently, the break-up location between India and Antarctica shifted from its initial to its final location along the northern portion of the Elan Bank formed by the western Krishna–Godavari Rift Zone. The competition between the two rift zones to capture continental break-up and asymmetric ridge propagation resulted in a ridge jump and the Elan Bank microcontinent release.Supplementary material:Supplementary figures are available at http://www.geolsoc.org.uk/SUP18864

An area of about 329 million hectares comprising the entire Indian territory has been studied using Landsat Multispectral Scanner (MSS) false colour composite (FCC) diapositives of 1 : 1 million scale. Different wasteland categories such as salt-affected land, gullied or ravined land, water-logged or marshy land, undulating upland with or without scrub, jhum or forest blank, sandy areas (coastal or desert), barren hill ridge or rock outcrops and snow-covered or glacial areas have been identified and delineated with the aid of monoscopic visual interpretation techniques on an experimental basis. The interpretation technique was supported by intensive ground data and previous geographical knowledge of the area. The area under wastelands in India has been estimated to be of the order of 53.3 million hectares (i.e., 16.2 per cent of the total geographical area of the country). An accuracy of 80 to 90 per cent has been achieved in the identification and mapping of wastelands when compared with the ground surveys. Based on this study, a detailed wasteland mapping project in 146 districts (the districts having 15 per cent or more of wastelands) has been conceived at the insistence of the National Wastelands Development Board at 1:50000 scale using Landsat Thematic Mapper (TM) FCC prints made from bands 2, 3 and 4. A suitable wasteland classification system adoptable for remote sensing techniques has also been developed in India. Furthermore a detailed wastelands image interpretation key using remotely-sensed Landsat TM data has also been developed and is presented in this paper.

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