Petrography and geochemistry of dolomites of the Surmeh Formation in the interior Fars region, southwest Iran


1 Department of Geology, Payame Noor University, Ahvaz, Iran

2 Geological Survey, University of Illinois, USA

3 Department of Geology, Islamic Azad University, Tehran, Iran


The Surmeh Formation (Toarcian-Tithonian) is the oldest lithostratigraphic unit of the Lower Jurassic-Lower Cretaceous Khami Group that crops out in parts of central and eastern Zagros Mountains. It is up to 1000 meters in parts of southwest Iran and is subdivided into three carbonate and two shale units. Petrographic and geochemical evidence (δ13C and δ18O isotopes and Mn, Fe, Mg, Sr, Na and Ca analysis) of the Surmeh Formation in the interior Fars has revealed the presence of four types of dolomites including micritic, finely crystalline, baroque and dolosparite, which have been originated near surface (tidal) to deep burial conditions. The main source of the Mg in these dolomites includes sea water, conversion of HMC to LMC, shale compaction and evaporite dissolution. The temperature formation of the early and baroque dolomites is calculated to be 33 and 74ºC respectively.


آدابی، م. ح.، 1383، ژئوشیمی رسوبی، انتشارات آرین زمین، 448 ص.
جلیلیان، ع. ح.، 1389، چینه نگاری سکانسی سازند سورمه در زاگرس مرکزی، جنوب باختر ایران، رساله دکتری، دانشگاه تربیت معلم تهران، 205 ص.
جلیلیان، ع. ح.، 1390، کانی شناسی اولیه کربنات­های سازند سورمه (ژوراسیک زیرین-بالایی) در فارس داخلی و عوامل کنترل کننده آن، مجموعه مقالات پنجمین همایش تخصصی زمین شناسی دانشگاه پیام نور، ص 846-841.
جلیلیان، ع. ح؛ لاسمی، ی. و آقانباتی، ع.، 1387، گذر از ژوراسیک آغازین به میانی در پهنه زاگرس: رخساره­ها و محیط رسوبگذاری بخش آغازین سازند سورمه، مجموعه مقالات دوازدهمین همایش انجمن زمین شناسی ایران، جلد سوم، ص 34-40.
محمودی، ل.، 1385، ژئوشیمی، دیاژنز و محیط رسوبی سازند سورمه فوقانی در میدان نفتی سلمان واقع در بخش مرکزی خلیج فارس، پایان نامه کارشناسی ارشد، دانشکده علوم زمین، دانشگاه شهید بهشتی، 115 ص.
هوشمندزاده، ع.؛ سهیلی، م. و حمدی، ب.، 1369، شرح نقشه زمین شناسی چهارگوش اقلید. مقیاس 1:250000، سازمان زمین شناسی کشور، شماره 10G.
 Adams, J. E., Rhodes, M. L., 1960, Dolomitization by seepage Reflexion, AAPG Bulletin, No: 44, p: 1912-1920.
 Allan, J.R. and WIGGINS, W.D., 1993, Dolomite Reservoirs: Geochemical Techniques and Evaluating Origin and Distribution. AAPG Continuing Education Course NotesSeries 36, 129 p.
Alsharhan, A.S., Nairn, A. E. M., 2003, Sedimentary basins and petroleum geology of the Middle East, Elsevier, 843 p.
 Braithwaite, C. J. R., 1989, Stylolites as open fluid conduits, Marine and Petroleum Geology, No: 6, p: 93-96.
Cantrell, D. L. and Hagerty, R. M., 1999, Microprosity in Arab Formation carbonates, Saudi Arabia, GeoArabia, Bahrain, V: 4, No: 2, p: 129-145.
Demicco, A. V., Hardie, L. A., 1994, Sedimentary Structures and Early Diagenetic Features of Shallow Marine Carbonate Deposits, SEPM Atlas Series Number 1, 265 p.
 Dickson, J.A.D., 1966, Carbonate identification and genesis as revealed by staining, Journal of Sedimentary Petrology, No: 36, p: 505.
 Eren, M., Kaplan, M. Y., Kadir, S., 2007, Petrography, Geochemistry and origin of Lower Liassic dolomites in the Aydinick Area, Mersin, southern Turkey, Turkish Journal of Earth Sciences, No: 16, p: 339-362.
Folk, R. L., Land, L. S., 1975, Mg/Ca ratio and salinity: two controls over crystallization of dolomite, AAPG Bulletin, No: 59, p: 60-68.
Friedman, I., O'Neil, J. R., 1977, Complication of stable isotope fractionation factors of geochemical interest, In: Fleischer, M. (Ed.), Data of geochemistry (6th edition). US Geological Survey, Professional Paper, No: 44, p: 1-12.
Illing, L.V., Taylor, J.C.M., 1993, Penecontemporaneous dolomitization in sabkha Faishakh, Qatar-evidence from changes in the chemistry of the interstitial brines, Journal of Sedimentary Petrology, No: 63, p: 1042-1048.
James, G.A., Wynd, J.G., 1965, Stratigraphic Nomenclature of Iranian oil consortium agreement area, AAPG, V: 49, No: 12, p: 2182-2245.
Kamen-Kaye, M., 1970, Geology and Productivity of Persian Gulf Synclinorium, AAPG, V: 54, No: 12, p: 2371-2394.
Land, L. S., 1985, The origin of massive dolomite, Journal of Geology Education, No: 33, p: 112-125.
Land, L. S., Hoops, G. K., 1973, Sodium in carbonate sediments and rocks: a possible index to salinity of diagenetic solutions, Journal of Sedimentary Petrology, No: 43, p: 614-617.
 Lasemi, Y., Jalilian, A. H., 2010, The Middle Jurassic basinal deposits of the Surmeh Formation in the Central Zagros Mountains, southwest Iran: Facies, Stacking Pattern and Controls. Carbonates and Evaporites, No: 25 (4), p: 283-395.
 Lee, L. S., Friedman, G. M., 1987, Deep-burial dolomitization in the Lower Ordovician Ellenburger Group carbonates in west Texas and southeastern New Mexico, Jour. Sed. Petrology, No: 57, p: 544-557.
 Magara, K., 1976, Water expulsion from clastic sediments during compaction-directions and volumes, AAPG Bulletin, No: 60, p: 543-553.
 Mackenzie, J., 1981, Holocene dolomitization of calcium carbonate sediments from the coastal sabkhas of Abu Dhabi, U.A.E., Journal of Geology, No: 89, p: 185-198.
 Mazzullo, S. J., 1992, Geochemical and neomorphic alteration of dolomite: a review, Carbonates and Evaporites, No: 7, p: 21-37.
 McHargue, T. R., Price, R. C., 1982, Dolomite from clay in argillaceous or shale associated marine carbonates, Jour. of Sed. Petrology, No: 48, p: 799-814.
 Moore, C. H., 1989, Carbonate Diagenesis and Porosity, Developments in Sedimentology, 46, Elsevier, 338 p.
 Mukhopadhyay, J., Chanda, S. K., Fukuoka, M., Chaudhuri, A. K., 1996, Deep-water dolomites from the Protrozoic Panganga Group in the Prinhita-Godavari valley, Andhra Pradesh, India, Jour. of Sed. Research, No: 66, p: 223-230.
Pingitore, N. R., 1978, The behavior of Zn and Mn during carbonate diagenesis: Theory and applications, Journal of Sedimentary Petrology, No: 48, p: 799-814.
Radke, B. M., Mathis, R. L., 1980, On the formation and occurrence of saddle dolomite, Jour. of Sed. Petrology, No: 50, p: 1149-1168.
Setudehnia, A., 1978, The Mesozoic sequence in southwest Iran and adjacent area, Journal of Petroleum Geology, V: 1, No: 1, p: 3-42.
Sibley, D. F., Gregg, G. M.,1987, Classification of dolomite rock texture, Jour. of Sed. Petrology No: 57, p: 967-975.
Swart, P. K., Cantrell, D. L., Westphal, H, Handford, C. R., Kendall, R. G., 2005, Origin of dolomite in the Arab-D reservoir from the Ghawar field, Saudi Arabia: Evidence from petrographic and geochemical constraints, Journal of Sedimentary Research, No: 75, p: 476-491.
Warren, J., 2001, Dolomite: occurrence, evolution and economically important associations, Earth-Science Reviews, No: 52, p: 1-18.
 Wynd, J.G., 1965, Biofacies of the Iranian oil Consortium agreement area, Iranian oil operating companies, Report No: 1082, 89 p.