Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas

Details Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas

Feb 1980

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1980e%26psl..46..344s&link_type=abstract

Earth and Planetary Science Letters, Volume 46, Issue 3, p. 344-360.

Computer Science

47

Scientific paper

Magnetic activity throughout the Antarctic Peninsula and the South Shetland Islands has been dominantly of a calc-alkaline nature for the last 200 Ma. Chemically, the plutonic and volcanic products are typical of a continental margin magmatic arc, similar to those from western South America. Within any one area, volcanic and plutonic rocks are compositionally indistinguishable, and all magmatic products show increasing SiO2, and increasing K/Si, Rb/Si, Th/Si and to a lesser extent Ce/Si and La/Si ratios away from the proposed trench axis. The calc-alkaline basaltic compositions also have high large ion lithophile (LIL; e.g. K, Rb, Th)/high field strength (HFS; e.g. Zr, Nb, Ti) ratios relative to non-orogenic counterparts, and increasing LIL/HFS element ratios with increasing fractionation. It is proposed that the high LIL/HFS element ratios in basaltic and andesitic melts are primary features due to dehydration processes with the subducted slab and to fractionation of minor mineral phases from the melt. The increasing LIL/HFS element ratios in more acid rocks are probably due to removal of minor mineral phases from the melt. Although zone refining may contribute to the spatial variations across the peninsula, we have proposed that an enriched subcontinental mantle provides a viable alternative source for the observed K-h variations and for the increased LIL-element contents found in continental margin calc-alkaline magmas.
Now at Department of Geology, University of Canterbury, Christchurch 1, New Zealand.

Affiliated with

Also associated with

No associations

Rating

Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas 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 Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1620882