Application of spectral analysis in sequence stratigraphy and Milancovich cycles identification in Sarvak Formation in Kupal Oilfield

Document Type : Research Paper

Authors

Abstract

The Sarvak Formation (Albian to Turonian) is one of the carbonate units in the southwest Iran that was deposited on Neotethys margin. The purpose of this study is to analysis sequence stratigraphy and to identify Milankovitch cyclesof this formation in wells No. 20 and 48 in the Kupal Oilfield. This study was done by MESA spectral analysis method, using Cyclolog software and gamma ray data. The study of 250 thin sections led to identification of 9 microfacies that were deposited in three depositional environments including lagoon, shoal and open marine. In additions two third order depositional sequences (based on facies variations and changes PEFA and INPEFA curves) were identified. Examination of Milankovitch cycles, using both interval variations between gamma ray peaks and MESA spectral analysis methods showed that most of them formed 100,000 years cycles type. Orbital age determination with respect to counting of these cycles showed that this part of drilled formation has 11 to12 million years age.

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منابع
[1] حقی، ع (1366) مطالعه زمین­شناسی مخزن بنگستان، میدان کوپال، گزارش شماره 4056، 51 ص.
[2] قلاوند، ه (1381) مطالعه تکمیلی زمین­شناسی مخزن بنگستان میدان کوپال، گزارش شماره 5254، 210 ص.
  [3] Abdel-Gawad. G.I., Saber. S.G., El Shazly.S.H., Salama. Y.F (2011) Turonian Rudist Facies from Abu Roash area, North Western Desert, Egypt, Journal of African Earth Sciences,Vol:59,p: 359 – 372.
[4] Adabi. M.H., Salehi. M.A., Ghabeishavi. A (2010) dipositional environment, sequences stratigraphy and geochemistry of Lower Cretaceous carbonates (Fahliyan Formation), south-west Iran, Journal of Asian Earth Sciences, Vol: 39,p: 148-160.
[5] Berger.A.,Loutre.M.F (1994) Astronomical forcing through geologicaltime, In: de Boer P.L. & Smith D.G. (eds.), Orbital forcing andcyclic sequences, IAS Special Publication, Oxford, Vol:19, p:15-24
[6] Carter. J (2002) The key to the future: the study of earth history, Published by Routledge,133p.
[7] De Jong. M., Smith. D., DjinNio. S., Hardy. N (2006) Subsurface correlation of the Triassic of the UK southern central graben: new look at an old problem, Vol:24, p:103–109.
[8] Dunham. R.J (1962) Classification of carbonate rocks according to depositional texture, in W.E. Ham, ed., Classification of carbonate rocks, American Association of Petroleum Geologist Memoir 1,  p: 108-121.
[9] Embery. A. F., Klovan. J. E (1971) A Late Devonian reef tract on northeastern Banks Island, Northwest territories: Bulletin of Canadian Petroleum Geology, Vol:19, p:730 – 781.
[10] Flugel. E (2010) Microfacies of carbonate rocks-analysis, interpretation andapplication, Springer, Berlin, 967 p.
[11] Ji-feng. YU.,Feng-gui. SUI., Zeng. LI., Hua. LIU., Wang. Yu-lin (2008) Recognition of Milankovitch cycles in the stratigraphic record: application of the CWT and the FFT to well-log data, J China Univ Mining and Technol, Vol:18, p:594-598.
[12] Kalvoda. J., O., Babek. F. X., Devuyast. G. S., Sevastopolo.G (2011) Biostratigraphy, sequence stratigraphy and gamma-ray spectrometry of the Tournaisian-Visean boundary interval in the Dublin Basin, Bulletin of Geosciences, Vol:86, p:683-706.
[13] Khalili. M (1974) Thebiostratigraphic synthesis of the Bangestan Group in southward Iran, Report 1219 , Tehran, Iranian Oil Operating Companies.
[14] Laurin. J., Cech. S., Ulicny. D., Staffen. Z., Svobodová. M (2014) Astrochronology of the Late Turonian: implications for the behavior of the carbon cycle at the demise of peak greenhouse, Earth Planet, Sci. Lett. 394, p:254–269.
[15] Molen, A (2004) Sedimentary development, seismic stratigraphyand burial compaction of the Chalk Groupin the Netherlands North Sea area, PhD dissertation, university of  Urtecht, 180 p.
[16] Nio. S.D., Brouwer. J., Smith. D., Jong. M., Böhm. A (2005) Spectral trend attribute analysis: applications in the stratigraphic analysis of wireline logs., Petrolume geology special topic,Vol: 23, p:71-75.
[17] Nio. S.D (2010) Cyclolog user guide, Enres International Company, 334 p.
[18] Prokoph. A., Villeneuve. M., Agterberg. F.P.,Rachold. V (2001) Geochronology and calibration of global Milankovitchcyclicity at the Cenomanian-Turonian boundary, Geology, Vol:29, p:523-526.
[19] Prokoph. A., Thurow. J (2000) Diachronous pattern of Milankovitchcyclicity in late Albian pelagic marlstones of the North German Basin, Sedimentary Geology, Vol:134, p:287-303.
[20] Skelton. P. W., Spicer. R. B., Kelley. S. P., Gilmour. L (2003) the Cretaceous world, Cambridge University Press, 360 p.
[21] Serra. O (1984) fundamentals of well-log interpretation-the acquisition of logging data, Elsevier, 435 p.
[22] Storz. D.,  Gischler. E., Parker. J., Klostermann. L (2014) Changes in diversity and assemblages of foraminifera through the Holocene in an atoll from the Maldives, Indian Ocean,Marine Micropaleontology, Vol:106, p:40-54.
[23] Tagliaferri. R., Pelosi. N., Ciaramella. A., Longo. G., Milani. M., Barone. F (2001) soft computing methodologies for spectral analysis in cyclostratigraphy, Computer and Geosciences, Vol:27,p: 535-548.
[24] Vilela. C.G., Batista. D.S., Baptista Neto. J.A., Ghiselli. R.O (2011) Benthic foraminifera distribution in a tourist lagoon in Rio de Janeiro, Brazil: A response to anthropogenic impacts, Marine Pollution Bulletin, Vol:62, p:2055-2074.
[25] Weedon. G. P., Coe. A. L., Gallois. R. W (2004) Cyclostratigraphy, orbital tuning and inferred productivity for the type Kimmeridge Clay (Late Jurassic), southern England, Journal of the Geological Society, London,Vol:161,p: 655-666.
[26] Westphal. H (2006) Limestone-marl alternations as environmental archives and the role of early diagenesis: a critical review, International Journal Earth Science, Vol:95,p: 947-961.
[27] Yilmaz. I. O., Altiner. D., Tekin. U. K., Tusuze. O., Ocakoglu. F., Acikalian. S (2010) Cenomanian – Turonian oceanic anoxic event (OAE2) in the Sakarya zone, northwestern Turkey: sedimentological, cyclostratigraphic, and geochemical records, Cretaceous Research, Vol:31,p:207-226.
[28] Zachos. J., Pagani. M., Sloan. L., Thomas. E., Katharina. B (2001) Trends, rhythms and aberration in global climate 65 Ma to present, Science, Vol:292, p:686-693.