The feasibility of antipodal volcanism as a result of the K/T impact

ABSTRACT
Research regarding the impact event at the Cretaceous-Tertiary (K/T) boundary at Chicxulub, Yucatan Peninsula, and the Deccan flood basalts of Western India has shown both possibility and dismissal of the two as being a series of interrelated events, although most workers agree that both sides were relatively antipodal at the K/T boundary. Subsequent 2D & 3D computer models following the development of Simplified Arbitrary Lagrangian-Eulerian (SALE) and similar code have shown that axial focusing of seismic waves following an impact for a planet analogous to earth is most significant at ~100 km depth below the antipode surface. However, calculations of the initial kinetic energy, total seismic energy produced as a function of the seismic efficiency for a C2 Chondrite bolide impact, and total energy delivered to a basaltic volume near its melting point at a depth of ~100 km generate a thermal pulse, or sudden change in temperature, of 1 millikelvin. This temperature increase is not sufficient to create or enhance pre-existing melts at depth. E
stimates of the total volume of lavas produced at the Deccan traps range from 1 x 10^5 to 1 x 10^6 km^3 over a duration of ~1 m.y., with average intervals between eruptions of sub-groups within the traps of 2-10,000 years. A stratigraphic section composed of main eruptive units within the traps shows one sub-group, the Wai, which is responsible for 50% of the total eruption volume from 66 to 64.5 Ma, peaking with the Ambenali Formation within the sub-group producing 200,000 km^3 of basalt 66 to 65.5 Ma. Activity substantially drops during the last two formations within the sub-group, Panhala and Desur, producing 25,000 and 10,000 km^3, respectively. A ~65 Ma date for the K/T impact would have had no effect on the Deccan trap system whose eruptive volumes were dropping per successive formation at this time.