Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India

Details Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India

Jan 1985

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1985e%26psl..72...39m&link_type=abstract

Earth and Planetary Science Letters, Volume 72, Issue 1, p. 39-53.

Other

24

Scientific paper

Concurrently erupted, alternating Deccan Trap flows of tholeiitic and potassic alkalic basalt outcrop along both banks of the Narmada River near Navgam. Nearby, around Rajpipla, early tholeiites are overlain by K-rich alkalic flows and intrusives, which are themselves cut by later tholeiitic dikes. Nd and Sr isotopic ratios of a wide variety of rocks from both areas form a single correlated array, which reflects mixing between positive ɛJUV and negative ɛJUV endmembers. There is an almost complete overlap between values for tholeiitic and alkalic samples; thus, both alkalic and tholeiitic primary magmas must have been produced that were isotopically much alike. A Rajpipla rhyolite also falls on the array, near the midpoint. For positive values of ɛJUV(T) the array is indistinguishable from that defined by the lower group of tholeiites at Mahabaleshwar, some 450 km to the south, implying a similar or identical high ɛJUV mantle source. The negative ɛJUV component, apparently different from either of the two at Mahabaleshwar, may have been continental crust or enriched mantle. Both alkalic and tholeiitic groups display wide overlapping ranges in incompatible elements other than K, Rb, and Ba-particularly in Sr and Nb. This partial decoupling of incompatible elements, in conjunction with the isotopic similarity between the two classes of rocks, is strongly suggestive of an enrichment event in portions of the mantle source shortly before magmatism.

Affiliated with

Also associated with

No associations

Rating

Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Origin of contemporaneous tholeiitic and K-rich alkalic lavas: a case study from the northern Deccan Plateau, India will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-926263