Petrology and Petrogenesis of Igneous Bodies of Divan-Daghy, Ghareh-Gose North of Marand (East Azarbaijan)

Abstract

Acidic and basic volcanic and intrusive rocks of Harzandat-Divan Daghy as individual masses, are located in North and Northwest of Marand (Harzandat) and South of Jolfa (Ghareh Gose-Divan Daghy) trending NW-SE.These rocks are located under Permian progressive deposits, which are covered by an igneous sole unconformity. Lithological composition of the acidic volcanic rocks ranges from dacite, rhyodacite to rhyolite, and basic volcanic rocks range from basalt to basaltic-andesite, where as plutonic rocks are of quartz-syenite. Major minerals of the acidic volcanic rocks and acidic intrusive bodies are quartz, plagioclase and K-feldspar and of the basic volcanic rocks are plagioclase, pyroxene and olivine. Minor minerals of these rocks are biotite, amphibole, sodic pyroxene, apatite, titanite and zircon. Emplacement of intrusions was in shallow depths as dyke, sill and small stocks and are of A-type. Studies show that acidic volcanic rocks are cognate to intrusive bodies and these rocks are A1 type. Basic volcanic rocks plot in two field on the discriminant diagrams for basalts: oceanic basalts and within plate basalts, therefore two possibilities may reinforced:1) either these basalts are the remanents of early Paleo-Tethys oceanic-crust or 2) these basalts were erupted in post collision and within plate environments perior to acidic eruptions and intruding of acidic masses. With respect to shoshonitic characteristics of these basalts which have been determined on the basis of immobile elements, and considering absence of shoshonitic rocks in oceanic environments the latter idea seems to be more acceptable.                                    

Keywords


[1] مؤید م.، مؤذن م.، "نگرشی نوبر موقعیت خط درز پالئوتتیس در ایران"، فشرده مقالات ششمین همایش انجمن زمین شناسی ایران، دانشگاه شهید باهنر کرمان (1381).

[2] Stocklin J., "Structural history and tectonics of Iran", A review Am Asso Petrol Geol B Vol 52 (1968) No 6.

[3] نبوی م.ح.، "دیباچه‌ای برزمین شناسی ایران"، انتشارات سازمان زمین‌شناسی کشور، (1355) 109 صفحه.

[4] افتخار نژاد ج.، "تفکیک بخش‌های مختلف ایران از نظر وضع ساختمانی در ارتباط با حوضه‌های رسوبی"، (1359).

[5] Whalen J.B., Currie K.L., and Chappell B.W., "A-type Granites: geochemical characteristics, discrimination and petrogenesis", Contrib Min Pet 95 (1987) 407-419.

[6] Eby G.N., "Chemical Subdivision of the A-type granitoides Petrogenesis and tectonic implications", Geology 20 (1992) 641 – 644.

[7] Irvine T.N., Baragar W.R.A., "A guide to the chemical classification of the common volcanic rocks", Can Earth Sci 8 (1971) 523-548.

[8] Kuno H., "Differentiation of basalt magmas, In: Hess H.H., and Poldervaart A.,(eds.) Basalts: The Poldervaart treatise on rocks of basaltic composition", Vol 2 Interscience New York (1968) pp 623-688.

[9] Pearce J.A., "Role of the sub-continental lithosphere in magma genesis at active continental margins", In: Hawkesworth C.J., and Norry M.J.,(eds)" Continental basalts and mantle xenoliths" Shiva Nantwich (1983) pp230-249.

[10] Pearce J.A., Harris N.B.W., Tindle A.G., "Trace element discrimination diagrams for the tectonic Interpretation of granitic rocks", Geol Soe Spec (1984) Publ, 7, 14 – 24.

[11] Maniar P.D., Piccoli P.M.,"Tectonic discrimination of granitoids", Geo Soc Am Bull Vol 10l (1989).

[12] Pearce J.A.,"Sources and settings of granitic rocks", (1996).

[13] مؤید م.، رضائی مقدم م.ح.، "اهمیت ژئودینامیکی گسل تبریز وگسل جنوبی میشو در تحول پوسته‌ای ایران"، خلاصه مقالات کنفرانس بین المللی مخاطرات زمین، بلایای طبیعی و راه کارهای مقابله با آنها، دانشگاه تبریز (1384).

[14] مؤید م.، مؤذن م.، کلاگری ع.ا.، حسین زاده ق.، "کانی‌شناسی و پترولوژی توده گرانیتوئیدی میشو (جنوب غرب مرند-آذربایجان شرقی) و اهمیت ژئودینامیکی آن"، مجموعه مقالات سیزدهمین همایش انجمن بلورشناسی و کانی‌شناسی ایران، دانشگاه شهید باهنر کرمان 141-146 (1384).

[15] Pearce J.A., and Cann J.R.,"Tectonic setting of basic volcanic rocks determined using trace element analyses", Earth Planet Sci (1973) Lett 19,290-300.

[16] Pearce J.A., Norry M.J., "Petrogenetic implications of Ti, Zr, Y and Nb variations in volcanic rocks", Contrib Mineral Petrol 69 (1979) 33-47.

[17] Boeinz et all., "Using geochemical data:Evaluation, Presentation, Interpretation", Rollinson H.R.,1993, Longman Scientific and Technical, England, (1984), 352 P.