Commercial oil flow has been obtained from the sandstone reservoir of the Lower Silurian Kelpintag Formation in the Well Shun-9 prospect area.In the present studies,10 Silurian oil and oil sand samples from six wells ...Commercial oil flow has been obtained from the sandstone reservoir of the Lower Silurian Kelpintag Formation in the Well Shun-9 prospect area.In the present studies,10 Silurian oil and oil sand samples from six wells in the area were analyzed for their molecular and carbon isotopic compositions,oil alteration（biodegradation）,oil source rock correlation and oil reservoir filling direction.All the Silurian oils and oil sands are characterized by low Pr/Ph and C21/C23 tricyclic terpane（〈1.0） ratios,＂V＂-pattern C27-C29 steranes distribution,low C28-sterane and triaromatic dinosterane abundances and light δ13C values,which can be correlated well with the carbonate source rock of the O3 l Lianglitage Formation.Different oil biodegradation levels have also been confirmed for the different oils/oil sands intervals.With the S1k2 seal,oils and oil sands from the S1k1 interval of the Kelpintag Formation have only suffered light biodegradation as confirmed by the presence of ＂UCM＂ and absence of 25-norhopanes,whereas the S1k3-1 oil sands were heavily biodegraded（proved by the presence of 25-norhopanes） due to the lack of the S1k2 seal,which suggests a significant role of the S1k2 seal in the protection of the Silurian oil reservoir.Based on the Ts/（Ts＋Tm） and 4-/1-MDBT ratios as reservoir filling tracers,a general oil filling direction from NW to SE has been also estimated for the Silurian oil reservoir in the Well Shun-9 prospect area.展开更多
The sedimentary Zhaojiazhuang Formation overlies the ancient Paleo-proterozoic crystalline basement in the middle-south sections of the Taihang Mountains,China.It is a complete stratigraphic sequence with clear bounda...The sedimentary Zhaojiazhuang Formation overlies the ancient Paleo-proterozoic crystalline basement in the middle-south sections of the Taihang Mountains,China.It is a complete stratigraphic sequence with clear boundaries.The formation has an angular unconformity with the underlying Paleo-proterozoic Tongyu Formation and a parallel unconformity with the overlying Changzhougou Formation from the Changcheng System,which is widely distributed throughout the W utai-Zhongtiao-T aihang Mountains.Qiu Zhen et al.(2007)and Wang Qingchun et al.展开更多
In 2013, a great breakthrough of deep petroleum exploration was achieved in the Cambrian pre-salt intervals of Wells Zhongshen1(ZS1) and Zhongshen1C(ZS1C), Tazhong Uplift. However, the hydrocarbon discovery in the Cam...In 2013, a great breakthrough of deep petroleum exploration was achieved in the Cambrian pre-salt intervals of Wells Zhongshen1(ZS1) and Zhongshen1C(ZS1C), Tazhong Uplift. However, the hydrocarbon discovery in the Cambrian pre-salt intervals has triggered extensive controversy regarding the source of marine oils in the Tarim Basin. The geochemistry and origin of the Cambrian pre-salt hydrocarbons in Wells ZS1 and ZS1 C were investigated using GC, GC-MS and stable carbon isotope technique. These hydrocarbons can be easily distinguished into two genetic families based on their geochemical and carbon isotopic compositions. The oil and natural gases from the Awatage Formation of Well ZS1 are derived from Middle-Upper Ordovician source rocks. In contrast, the condensate and gases from the Xiaoerbulake Formation of Wells ZS1 and ZS1 C probably originate from Cambrian source rocks. The recent discovery of these hydrocarbons with two different sources in Wells ZS1 and ZS1 C suggests that both Middle-Upper Ordovician-sourced hydrocarbons and Cambrian-sourced petroleums are accumulated in the Tazhong Uplift, presenting a great exploration potential.展开更多
A detailed correlation of Hetianhe condensates versus typical source rocks from the Tarim Basin was established. Moreover, the genetic relationship between the condensates and their associated gases was also studied b...A detailed correlation of Hetianhe condensates versus typical source rocks from the Tarim Basin was established. Moreover, the genetic relationship between the condensates and their associated gases was also studied based on their geochemical compositions and fluid inclusion data. Hetianhe condensates are characterized by high pristine/phytane(Pr/Ph) ratios, high relative abundances of C28 regular steranes, C26–C27 triaromatic steroids, and triaromatic dinosteranes, and relatively heavy stable carbon isotopic compositions. They geochemically correlate well with the Cambrian source rocks, indicating that these condensates are derived from the Cambrian rocks. Based on several molecular maturity parameters, the condensates are recognized as being moderately to highly mature, which are too low in maturity to extensively crack into gases. The gases and condensates of the Hetianhe Field are derived from the same source rocks and the gases are from oil-cracking; however, clear evidence indicates that the gases were not cracked from their associated condensates and that the gas generation from oil-cracking did not occur in the present reservoirs. The liquid condensates produced from wellheads were likely dissolved in their associated gases underground and carried into the reservoirs by the gases.展开更多
基金the Northwest Branch Company, SINOPEC for access to samples and grant support
文摘Commercial oil flow has been obtained from the sandstone reservoir of the Lower Silurian Kelpintag Formation in the Well Shun-9 prospect area.In the present studies,10 Silurian oil and oil sand samples from six wells in the area were analyzed for their molecular and carbon isotopic compositions,oil alteration（biodegradation）,oil source rock correlation and oil reservoir filling direction.All the Silurian oils and oil sands are characterized by low Pr/Ph and C21/C23 tricyclic terpane（〈1.0） ratios,＂V＂-pattern C27-C29 steranes distribution,low C28-sterane and triaromatic dinosterane abundances and light δ13C values,which can be correlated well with the carbonate source rock of the O3 l Lianglitage Formation.Different oil biodegradation levels have also been confirmed for the different oils/oil sands intervals.With the S1k2 seal,oils and oil sands from the S1k1 interval of the Kelpintag Formation have only suffered light biodegradation as confirmed by the presence of ＂UCM＂ and absence of 25-norhopanes,whereas the S1k3-1 oil sands were heavily biodegraded（proved by the presence of 25-norhopanes） due to the lack of the S1k2 seal,which suggests a significant role of the S1k2 seal in the protection of the Silurian oil reservoir.Based on the Ts/（Ts＋Tm） and 4-/1-MDBT ratios as reservoir filling tracers,a general oil filling direction from NW to SE has been also estimated for the Silurian oil reservoir in the Well Shun-9 prospect area.
基金supported by the National Science and Technology Major Project of China (grant No. 2016ZX05004001-004)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing (grant No. PRP/ open-1804)
文摘The sedimentary Zhaojiazhuang Formation overlies the ancient Paleo-proterozoic crystalline basement in the middle-south sections of the Taihang Mountains,China.It is a complete stratigraphic sequence with clear boundaries.The formation has an angular unconformity with the underlying Paleo-proterozoic Tongyu Formation and a parallel unconformity with the overlying Changzhougou Formation from the Changcheng System,which is widely distributed throughout the W utai-Zhongtiao-T aihang Mountains.Qiu Zhen et al.(2007)and Wang Qingchun et al.
基金supported by the Science Foundation of China University of Petroleum,Beijing(Grant No.2462015YQ0101)
文摘In 2013, a great breakthrough of deep petroleum exploration was achieved in the Cambrian pre-salt intervals of Wells Zhongshen1(ZS1) and Zhongshen1C(ZS1C), Tazhong Uplift. However, the hydrocarbon discovery in the Cambrian pre-salt intervals has triggered extensive controversy regarding the source of marine oils in the Tarim Basin. The geochemistry and origin of the Cambrian pre-salt hydrocarbons in Wells ZS1 and ZS1 C were investigated using GC, GC-MS and stable carbon isotope technique. These hydrocarbons can be easily distinguished into two genetic families based on their geochemical and carbon isotopic compositions. The oil and natural gases from the Awatage Formation of Well ZS1 are derived from Middle-Upper Ordovician source rocks. In contrast, the condensate and gases from the Xiaoerbulake Formation of Wells ZS1 and ZS1 C probably originate from Cambrian source rocks. The recent discovery of these hydrocarbons with two different sources in Wells ZS1 and ZS1 C suggests that both Middle-Upper Ordovician-sourced hydrocarbons and Cambrian-sourced petroleums are accumulated in the Tazhong Uplift, presenting a great exploration potential.
基金supported by the Science Foundation of China University of Petroleum,Beijing(Grant No.2462014YJRC017)
文摘A detailed correlation of Hetianhe condensates versus typical source rocks from the Tarim Basin was established. Moreover, the genetic relationship between the condensates and their associated gases was also studied based on their geochemical compositions and fluid inclusion data. Hetianhe condensates are characterized by high pristine/phytane(Pr/Ph) ratios, high relative abundances of C28 regular steranes, C26–C27 triaromatic steroids, and triaromatic dinosteranes, and relatively heavy stable carbon isotopic compositions. They geochemically correlate well with the Cambrian source rocks, indicating that these condensates are derived from the Cambrian rocks. Based on several molecular maturity parameters, the condensates are recognized as being moderately to highly mature, which are too low in maturity to extensively crack into gases. The gases and condensates of the Hetianhe Field are derived from the same source rocks and the gases are from oil-cracking; however, clear evidence indicates that the gases were not cracked from their associated condensates and that the gas generation from oil-cracking did not occur in the present reservoirs. The liquid condensates produced from wellheads were likely dissolved in their associated gases underground and carried into the reservoirs by the gases.
