Petrogenesis and Tectonic Implications of Bakter intrusive complex (south of Sonqor, western Iran),

Document Type : Original Article


1 تهران - خیابان مفتح - پلاک 43، دانشگاه خوارزمی، دانشکده علوم زمین

2 تهران- خیابان مفتح - پلاک 43 - دانشگاه خوارزمی - دانشکده علوم زمین

3 زنجان، دانشگاه زنجان، دانشکده علوم، گروه زمین شناسی



The Bacter intrusive igneous complex is located in Sanghar city area, Kermanshah province and in terms of tectonic-sedimentary divisions, it is located in the Sanandaj-Sirjan zone. Based on field studies, petrology and geochemistry, the composition of the intrusive complex includes gabbro, syenite, alkali syenite and quartz syenite. In petrographic studies, hyperidiomorphic granular, poikilitic, perthite and granophyric textures as well as sieve texture are observed in syenites and the main minerals are alkali feldspar, plagioclase, clinopyroxene, amphibole and biotite. Geochemical data indicate that these rocks are alkaline in nature. Textural evidence, such as disequilibrium textures such as sieve texture in plagioclase, can be attributed to either magmatic transformations during emplacement in multiple magma cells and mixing between the differentiated phases in these sub-reservoirs with crustal and mafic magma. Field characteristics and microscopic evidence as well as geochemistry of these rocks indicate a common origin between mafic and acidic phases. Partial melting and mixing are the most important factors in the formation of intrusive rocks in the region. This process is determined by the La/Yb ratio against La. The results obtained in this research include the enrichment of LREE elements compared to HREE, positive anomaly of Pb, depletion of Nb and Ti elements, and other results, the possible role of crustal pollution in the acidic parts of the Bacter complex. It expresses the dependence of intrusive mass-generating melts on post-collision extensional phases and behind the magmatic arc. The presented geochemical patterns indicate that the mother magma of the studied rock complex, including


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Articles in Press, Accepted Manuscript
Available Online from 08 May 2024
  • Receive Date: 28 May 2023
  • Revise Date: 03 February 2024
  • Accept Date: 08 May 2024