Record Details

Do major oxide tectonic discrimination diagrams work? Evaluating new log-ratio and discriminant-analysis-based diagrams with Indian Ocean mafic volcanics and Asian ophiolites

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Do major oxide tectonic discrimination diagrams work? Evaluating new log-ratio and discriminant-analysis-based diagrams with Indian Ocean mafic volcanics and Asian ophiolites
 
Creator SHETH, HC
 
Subject geochemical discrimination
chemical classification
statistical-analysis
field boundaries
reunion hotspot
barren island
andaman sea
rocks
basalts
lavas
 
Description Many geochemical diagrams exist that classify old volcanic terranes of ambiguous provenance into various modern plate tectonic settings, with variable success. Recently proposed diagrams, based on log-ratios and linear discriminant analysis with large datasets of major oxides, were tested here with data for ocean island, arc and mid-ocean ridge lavas from the Indian Ocean. Success rates are 45-100%, with misclassifications potentially caused by alteration, although alteration demonstrably need not cause misclassification. The diagrams were further applied to some Asian ophiolites, representing Tethyan and Indian ocean crusts, to see if the diagrams confirm their tectonic setting inferred from trace and isotopic data. Lower success rates (30-60%, but 75-100% for specific suites) are not surprising in view of the ubiquitous and complex alteration in ophiolites. Log-ratio transformation and linear discriminant analysis appear to be powerful methods when discrimination diagrams are based on major oxide data alone.
 
Publisher BLACKWELL PUBLISHING
 
Date 2011-07-19T03:40:39Z
2011-12-26T12:50:59Z
2011-12-27T05:37:15Z
2011-07-19T03:40:39Z
2011-12-26T12:50:59Z
2011-12-27T05:37:15Z
2008
 
Type Article
 
Identifier TERRA NOVA, 20(3), 229-236
0954-4879
http://dx.doi.org/10.1111/j.1365-3121.2008.00811.x
http://dspace.library.iitb.ac.in/xmlui/handle/10054/5163
http://hdl.handle.net/10054/5163
 
Language en