General investigation of magmatic rocks,NE Mshhad -Fireman ? Torbatjam lineament

Category Petrology
Group GSI.IR
Location 23th symposium on geosciences
Holding Date 05 May 2008

      Mashhad ? Fariman ? Torbatjam lineament in the North east of Iran is a lithotectonic boundary,since there is two different types of Permian lithofacies on each side of it . Despite it?s significance , this area especially it?s North east magmatic rocks have not been studied complet ely . In addition there are some discrepancies about the nature of ultramafic ? mafic magmatic rocks. in general , there are two interpretation about these rocks:
   Geologist who consider these magmatic rocks and associat ed sediments as a ophiolitic remnants of pal eotethys ( eg. Alavy,S.M 1991 , shtoklin , j. 1974 ) , and others who consider them as a volcanic sequence with komatiitic affinity ( eg. Sabzehee, M . 1373 , Magid ,B . 1983 ) .
   Investigation of documents relat ed to both of discussed ideas show that there are some evidences ,including field observations and petrographic features that favour the later idea . However , the absence of precise geochemical data such as microprob, trace el ement and isotopic analysis is the major problem that inhibited us for a detail petrogenesis int erpretation . here , just for a general treat , major el ement data of three samples are investigated to indicate the Al2O3 deplet ed komatiitic affinity of these rocks .