Geochemistry of the fracture-cave calcite of the Ordovician Yingshan Formation and its paleokarst environment in the Tazhong area, Tarim Basin, China

  • Yong Dan
  • Liangbiao LinEmail author
  • Bin Liang
  • Qingyu Zhang
  • Jianwen Cao
  • Jingrui Li
Original Article


The fracture-cave reservoir of the Yingshan Formation is an important oil and gas producing zone in the Tarim Basin. Karstification occurs at the top surface of the carbonate rocks of the Yingshan Formation on the northern slope of the Tazhong area due to a short exposure, so abundant fracture-cave spaces are formed. On the basis of the data of nearly 49 samples obtained from 21 wells, the carbon and oxygen isotopes of the fracture-cave calcite were analyzed. The carbon and oxygen stable isotopic characteristics recorded during paleokarstification were discussed to provide geochemical evidence for predicting the distribution of the fracture-cave reservoirs, as well as to understand the genetic mechanism of karst fracture-caves and the fluid properties and paleo-hydrological conditions of paleokarstification. The fracture-cave calcite can be divided into three types based on its carbon and oxygen isotope values, which indicate three types of paleokarst environments with different fluid properties. Type I calcite has similar carbon and oxygen isotope values to the bedrock of the Yingshan Formation, with δ13C values of − 2.0 to 1.1‰ and δ18O values of − 5.76 to − 8.16‰. These values indicate that the calcite was precipitated in the eogenetic karst environment of the Yingshan Formation. Type II calcite has a δ13C value of − 2.13 to 1.0‰ and a δ18O value of − 12.41 to − 8.0‰. It has a similar δ13C value, but a significantly negative oxygen isotope value compared with values of the bedrock of the Yingshan Formation, indicating a buried karst environment. Type III calcite has an extremely negative δ18O value (δ18O value < − 14.50‰), indicating hypothermal karst genesis. Its formation is related to magma or deep hydrothermal fluids. No calcite with atmospheric freshwater genesis and significantly negative δ13C and δ18O values was found in the samples, indicating that the formation of fracture-caves is weakly affected by atmospheric freshwater. The main reservoir space of the Yingshan Formation is karst caves. The calcite in the karst cave fillings belongs to type I, indicating an eogenetic karstification environment. Therefore, the formation of the fracture-cave reservoirs of the Yingshan Formation in the Tazhong area is related to eogenetic karstification, which occurred during exposure and mainly contributed to the formation of the reservoir spaces.


Carbon and oxygen isotopes Paleokarst environment Paleokarst reservoir Eogenetic karstification Tarim basin Yingshan Formation 



This paper was supported by the Geological Survey Program of China Geological Survey (No. DD20190723), the Nonprofit Industry Research Program of Chinese Academy of Geological Sciences (No. YYWF201723) and the National Key R&D Program of China (No. 2018YFC0604301). Senior Engineer Zhang Zheng-Hong of the Research Institute of Exploration and Development at Tarim Oilfield Company of PetroChina have been of great assistance during the core observations and sample collection processes. Mr. Deng Zhen-ping (Manager) and Senior Engineer Yang Hui of the Karst Geology Resources and Environment Test Center of the Ministry of Land have been of great support during the sample testing and analysis processes.


  1. Arthur MA, Dean WE, Pratt LM (1988) Geochemical and climatic effects of increased marine organic carbon burial at the Cenomanian/Turonian boundary. Nature 335:714–717CrossRefGoogle Scholar
  2. Cai CF, Li KK, Cal LL, Li B, Jiang L (2009) Geochemical characteristics and origins of fracture-and vug-fillings of the Ordovician in Tahe oilfield, Tarim basin. Acta Petrol Sin 25(10):2399–2404 (in Chinese with English abstract) Google Scholar
  3. Chen XS, Yi WX, Lu WZ (2004) The Paleokarst reservoirs of oil/gas fields in China. Acta Sedimentol Sin 22(2):243–252 (in Chinese with English abstract) Google Scholar
  4. Chen HH, Wu Y, Zhu HT (2016) Eogenetic karstification and reservoir formation model of the Middle-Lower Ordovician in the northeast slope of Tazhong Uplift, Tarim Basin. Acta Petrol Sin 37(10):1231–1246 (in Chinese with English abstract) Google Scholar
  5. Craig H (1961) Standard for reporting concentrations of deuterium and oxygen-18 in natural water. Science 133:1702–1703CrossRefGoogle Scholar
  6. Dan Y, Liang B, Cao JW (2012) Geochemical features and environmental significances of deposits in Ordovician karstic fractures and caves, Lunnan area, Tarim Basin. Petrol Geol Exp 34(6):623–628 (in Chinese with English abstract) Google Scholar
  7. Dan Y, Liang B, Cao JW, Zhang QY, Hao YZ (2015) Eogenetic karstification in carbonatite and its significance for hydrocarbon geology. Carsologica Sin 34:126–135 (in Chinese with English abstract) Google Scholar
  8. Dan Y, Lin LB, Liang B, Zhang QY, Yu Y, Cao JW, Li JR (2018) Eogenetic karst control of carbonate reservoirs during a transient exposure: a case study of the Ordovician Yingshan formation in the Northern slope of the Tazhong uplift, Tarim Basin, China. Minerals 8(8):345CrossRefGoogle Scholar
  9. Feng RW, Ou YC, Pang YJ, Li ZZ, Luo X, Zhang Q, Li SY, Zhou Y, Cheng L (2014) Evolution modes of interbedded weathering crust karst: A case study of the 1st and 2nd members of Ordovician Yingshan Formation in EPCC block, Tazhong, Tarim Basin. Petrol Explor Dev 41:49–59CrossRefGoogle Scholar
  10. He J, Han JF, Pan WQ (2007) Hydrocarbon accumulation mechanism in the giant buried hill of Ordovician in Lunnan paleohigh of Tarim Basin. Acta Petrol Sin 28(2):44–48 (in Chinese with English abstract) Google Scholar
  11. Keith MH, Weber JN (1964) Carbon and oxygen stable isotopic composition of selected limestones and fossils. Geochim Cosmochim Acta 28(11):1787–1816CrossRefGoogle Scholar
  12. Kong XG (2009) Advance in study of oxygen and carbon isotope variations in cave stalagmites as palaeo-climate proxies. Geol J China Univ 15(2):165–217 (in Chinese with English abstract) Google Scholar
  13. Lan XD, Lü XX, Zhu YM (2014) Characteristics and differential accumulation of oil/gas in Lower Paleozoic marine carbonate on northern slope of Tazhong Low Rise, Tarim Basin, NW China: a case study of Lower Ordovician Yingshan Formation. Arab J Geosci 7:4487–4498 (in Chinese with English abstract) CrossRefGoogle Scholar
  14. Li K, Cai C, He H (2011) Origin of palaeo-waters in the Ordovician carbonates in Tahe oilfield, Tarim Basin: constraints from fluid inclusions and Sr, C and O isotopes. Geofluids 11:71–86CrossRefGoogle Scholar
  15. Liu CG, Li GR, Zhu CL (2008) Geochemistry characteristics of carbon, oxygen and strontium isotopes of calcites filled in Karstic Fissure-Cave in Lower-Middle Ordovician of Tahe Oilfield, Tarim Basin. Earth Sci J China Univ Geosci 33(3):377–386 (in Chinese with English abstract) Google Scholar
  16. Ni XF, Shen A, Pan WQ (2013) Geological modeling of excellent fractured-vuggy carbonate reservoirs: a case study of the Ordovician in the northern slope of Tazhong palaeouplift and the southern area of Tabei slope, Tarim Basin. Petrol Explor Dev 40:414–422CrossRefGoogle Scholar
  17. O’Neil JR, Clayton RN, Mayeda TK (1969) Oxygen isotope fractionation in divalent metal carbonates. J Chem Phys 51(12):5547–5558CrossRefGoogle Scholar
  18. Pang H, Chen JQ, Pang XQ (2013) Key factors controlling hydrocarbon accumulations in Ordovician carbonate reservoirs in the Tazhong area, Tarim basin, western China. Mar Pet Geol 43:88–101CrossRefGoogle Scholar
  19. Rahimpour-Bonab H, Mehrabi H, Enayati-Bidgoli AH, Omidvar M (2012) Coupled imprints of tropical climate and recurringemersions on reservoir evolution of a mid-Cretaceous carbonateramp, Zagros basin, SW Iran. Cretac Res 37:15–34CrossRefGoogle Scholar
  20. Rahimpour-Bonab H, Mehrabi H, Navidtalab A, Omidvar M, Enayati-Bidgoli AH, Sonei R, Sajjadi F, Amiri-Bakhtyar H, Arzani N, Izadi-Mazidi E (2013) Palaeo-exposure surfaces in Cenomanian-Santonian carbonate reservoirs in the Dezful Embayment. SW Iran J Petrol Geol 36(4):335–362CrossRefGoogle Scholar
  21. Scholle PA, Arthur MA (1980) Carbon isotope fluctuations in Cretaceous pelagic limestones: potential stratigraphic and petroleum exploration tool. Bull Am Assoc Pet Geol 64:67–87Google Scholar
  22. Schopf TJM (1980) Paleoceanography. Harvard Univ. Press, Cambridge, pp 106–107CrossRefGoogle Scholar
  23. Shao YL (1994) The relation of the oxygen and carbon isotope in the carbonate rocks to the paleotemperature etc. J China Univ Min Technol 23(1):39–45 (in Chinese with English abstract) Google Scholar
  24. Shu ZG, Zhu ZD, He XP (2008) Reservoir characteristics of palaeokarsts in the tazhong uplift. XinJiang Geology 26(3):274–278 (in Chinese with English abstract) Google Scholar
  25. Veizer J, Ala D, Azmy K, Bruckschen P, Buhl D, Bruhn F, Carden GAF, Diener A, Ebneth S, Godderis Y, Jasper T, Korte C, Pawellek F, Podlaha OG, Strauss H (1999) 87Sr/86Sr, δ 13C and δ 18O evolution of Phanerozoic seawater. Chem Geol 161(1):59–88CrossRefGoogle Scholar
  26. Yan XB, Han ZH, Li YH (2002) Reservoir characteristics and formation mechanisms of the Ordovician carbonate pools in the Tahe Oilfield. Geol Rev 48(6):619–626 (in Chinese with English abstract) Google Scholar
  27. Yan XB, Li TJ, Zhang T (2005) Differences between formation conditions of Ordovician karstic reservoirs in Tazhong and Tahe areas. Oil Gas Geol 26(2):202–209 (in Chinese with English abstract) Google Scholar
  28. Yang HJ, Han JF, Sun CH (2011) A development model and petroleum exploration of karst reservoirs of Ordovician Yingshan formation in the northern slope of Tazhong palaeouplift. Acta Petrol Sin 32:199–205 (in Chinese with English abstract) Google Scholar
  29. Yu HF, Bai ZK, Deng LP (2011) Determination and geologic significance of Yingshan unconformity of lower Ordovician in Tazhong area, Tarim Basin. Xinjiang Petrol Geol 32:231–234 (in Chinese with English abstract) Google Scholar
  30. Zhang XL (1985) Relationship between carbon and oxygen stable isotope in carbonate rocks and paleo-salinity and paleo-temperature of sea water. Acta Sedimentol Sin 3(4):17–30 (in Chinese with English abstract) Google Scholar
  31. Zhang ZH, Dan Y, Liang B, Zhang QY, Li JR, Hao YZ (2015) Characteristics of oxygen and carbon isotopes of karst fissure-cave fillings in the Yingshan formation, Tazhong II area, Tarim basin and their implications for environment. Carsol Sin 34(2):159–164 (in Chinese with English abstract) Google Scholar
  32. Zhang H, Cai ZX, Qi LX, Yun L (2016a) Types and characteristics of eogenetic karst in the Yingshan Formation in northwestern Tazhong area, Tarim Basin. Oil Gas Geol 37:291–303 (in Chinese with English abstract) Google Scholar
  33. Zhang QY, Liang B, Qin FR (2016b) Environmental and geochemical significance of carbon and oxygen isotopes of Ordovician carbonate paleokarst in Lunnan, Tarim Basin. Environ Earth Sci 75:1074–1079CrossRefGoogle Scholar
  34. Zhang QY, Qin FR, Liang B, Cao JW, Dan Y (2016c) Characteristics of Ordovician paleokarst inclusions and their implications for paleoenvironmental and geological history in Halahatang area of northern Tarim Basin. Carbonates Evaporites 1–12Google Scholar
  35. Zhao WZ, Shen AJ, Pan WQ, Zhang BM, Qiao ZF, Zheng JF (2013) A research on carbonate karst reservoirs classification and its implication on hydrocarbon exploration: cases studies from Tarim Basin. Acta Pet Sin 29:3213–3222 (in Chinese with English abstract) Google Scholar
  36. Zhu GY, Zhang SC, Wang HH, Yang HJ, Meng SC, Gu QY (2009) The formation and distribution of deep weathering crust in north Tarim basin. Acta Petrol Sin 25:2384–2398 (in Chinese with English abstract) Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute of Karst GeologyChinese Academy of Geological Sciences/Karst Dynamics Laboratory, MNR & GZARGuilinChina
  2. 2.State Key Laboratory of Oil and Gas Reservoir Geology and ExploitationChengdu University of TechnologyChengduChina
  3. 3.Institute of Sedimentary GeologyChengdu University of TechnologyChengduChina

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