Deccan basalts

Figure 3.2 Examples of mesa-like remnants of a Late Cretaceous lateritised palaeosurface developed on Deccan basalt from widely separated localities across the Maharashtra Plateau, western India. On the eastern reaches of the Deccan (A) Bidar (17°55 N, 77°33 E) (B) Bidar area (17°53 N, 77°36 E) on the western reaches of the Deccan c. 400 km from Bidar, (C) Panchgani (17°56 N, 73°49 E) (D) Patan (17°23 N, 73°56,E). In all these areas, the mechanically resistant upper layers of the laterite profile typically form a protective capping to the less altered materials beneath and, following erosion, producing a characteristic cliff-like morphology.

Table 3.2 Geochemical analyses (by XRF) of autochthonous laterite profiles (A) Developed on Deccan basalt exposed at Bldar, India (see Figures 3.2A and 3.3)... 

Examples of mesa-like remnants of a Late Cretaceous lateritised palaeosurface developed on Deccan basalt from widely separated localities across the Maharashtra Plateau, western India. 

Geochemical analyses of autochthonous laterite profiles developed on Deccan basalt exposed at Bidar, India and on Proterozoic greywacke exposed at Merces Quarry near Panjim, Goa, India. 

Basu A. R., Renne P. R., Dasgupta D. K., Teichmann F., and Poreda R. J. (1993) Early and late alkah igneous pulses and a high He plume origin for the Deccan flood basalts. Science 261, 902-906. 

CourtiUot V., Besse J., Vandamme D., Montigny R., Jaeger J. J., and Cappeta H. (1999) Deccan flood basalts at the Cretacous/ Tertiary boundary Earth P/anct. Sci. Lett. 80, 361—374. 

Mahoney J. J. (1988) Deccan Traps. In Continental Flood Basalts (ed. J. D. Macdougall). Kluwer Academic, Dordrecht, 341pp. 

They include continental flood basalts of the type found in the Deccan plateau in India or the Karoo province of southern Africa, and, where the volcanism is within oceanic crust, oceanic plateaus. Most Mesozoic and Cenozoic LIPs had an original areal extent of more than a million km2 and represent magma volumes of up to 4 million km3. The Ontong Java oceanic plateau has a lava volume of 6 million km3 and when extrusive and intrusive components are aggregated a total volume of 44.4 million km3 (Ernst et al., 2005). 

Peng ZX, Mahooney J, Hooper P, Harris C, Beane J (1994) A role for lower continental crust in flood basalt genesis Isotopic and incompatible element study of the lower six formations of the western Deccan traps. Geochim Cosmochim Acta 58 267-288 Perry EA, Gieskes JM, Lawrence JR (1976) Mg, Ca and exchange in the sediment-pore water... 

Baksi AK (1994) Geochronological Studies On Whole-Rock Basalts, Deccan Traps, India—Evaluation of the Timing of Volcanism Relative to the K-T Boundary. Earth Planet Sci Lett 121 43-56 Ballentine CJ, Bumard P (2002) Production and release of noble gases in the continental crust. Rev Mineral Geochem 47 481-538... 

Some of the pioneering zeolite research has been carried out on heulandite with the simplified formula Ca4AlgSi28072 nH20 because large crystals of this species are available in limited quantities from cavities and vugs in volcanic rocks, e.g. in the Deccan Trap basalts of Western India [3]. Already in 1934 Tiselius [4] studied the temperature, pressure, and concentration dependence of the anisotropic H2O diffusion in heulandite single-crystals. Other... 

First, it wasn t just, or even primarily, a meteor. Increasingly, studies are finding that geological imrest increased well before that fatal star appeared in the Cretaceous skies. The Deccan province, now in India, spewed more than a million cubic kilometers of basalt into the biosphere in about a million years of eruptions that began 250,000 years before the asteroid impact. The eruptions are inevitable stress with impredictable timing. 

LIP (Large Igneous Province) is a large basaltic continental or oceanic igneous province, generally composed at the surface of flood basalts (e.g., Deccan Traps, Iceland). 

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