The upper Ganchaigou Formation reservoir in Zahaquan area of Qaidam Basin is an important exploration block for tight oil but has poor reservoir physical properties and strong heterogeneity.It is found that beach bar is the main sedimentary type in this area.It is important to understand the sand body architecture and spatial distribution of beach bar sand body for the development of tight oil sweet area.Based on the abundant data of core，logging，analysis，testing and production，this paper studies the sand body architecture of beach bar microfacies in Zahaquan area，and explores its relationship with the distribution of tight oil and gas.The beach bar Sands of Ganchaigou Formation in Zahaquan are shore and shallow lake subfacies，which are further subdivided into four microfacies：Dam，dam edge，beach and shallow lake mud.Through core calibration logging，the corresponding logging facies model is established.This paper summarizes three criteria for judging whether a dam is the same or not under the condition of sparse well pattern，namely，the elevation difference between adjacent dams，the phase change of a single dam and the shape difference of logging curves.Four single dam bodies of three-stage deposits were identified in Ⅳ-3 sublayer of block Za-2 by the techniques，and five single dam bodies of three-stage deposits were identified in Ⅳ-1 sublayer.There are three types of sand bodies in the beach bar sandbody of Zahaquan area：Lithologic pinch-out sandbody，single sand body isolated sandbody and physical barrier sandbody.The Development Zone in the dam controls the distribution of tight oil sweet areas.
Xia Xiao-min, Wu Yan-xiong, Zhang Shen-qin, Xue Jian-qin, Wang Lan, Shi Qi, Cui Han, Zhao Quan
. Study on sand body architecture of lacustrine beach-bar and significance for development of tight oil sweet areas：Case study of Well Za-2 area in Zahaquan area，Qaidam Basin[J]. Natural Gas Geoscience, 2019
, 30(8)
: 1158
-1167
.
DOI: 10.11764/j.issn.1672-1926.2019.07.006
［1］Jiang Xiemei，Wan Xinzheng，Li Jishan，et al.Microfacies division and lateral prediction of beach bar sand in the fourth member of Shahejie Formation in Dongying Depression：A case study of Wang73 Well area in Wangjiagang Oilfield[J].Petroleum Geology and Engineering，2007，21(4)：12-15.
蒋解梅，王新征，李继山，等.东营凹陷沙四段滩坝砂微相划分与砂体横向预测——以王家岗油田王73井区为例[J]．石油地质与工程，2007，21(4)：12-15.
[2]Zhang Shanwen.Thinking and practice of Tertiary oil and gas exploration of maturing region in eastern China：A case study of Jiyang depression[J].Acta Petrolei Sinica，2012，33(supplement 1)：53-62
张善文.中国东部老区第三系油气勘探思考与实践——以济阳坳陷为例[J]．石油学报，2012，33(增刊1)：53-62.
[3]Yang Yongqiang，Qiu Longwei，Jiang Zaixing，et al.A depositional pattern of beach bar in continental rift lake basins：A case study on the upper part of the fourth member of the Shahejie Formation in the Dongying Sag[J].Acta Petrolei Sinica，2011，32(3)：417-423.
杨勇强，邱隆伟，姜在兴，等.陆相断陷湖盆滩坝沉积模式——以东营凹陷古近系沙四上亚段为例[J]．石油学报，2011，32(3)：417-423.
[4]Yue Dali，Wu Shenghe，Liu Jianmin.An accurate method for anatomizing architecture of subsurface reservoir in point bar of meandering river[J].Acta Petrolei Sinica，2007，28(4)：99-103.
岳大力，吴胜和，刘建民.曲流河点坝地下储层构型精细解剖方法[J]．石油学报，2007，28(4)：99-103.
[5]Li Yupeng，Wu Shenghe，Geng HuiLi，et al.Spatial-vector-based reservoir architecture modeling of point-bar sand[J].Acta Petrolei Sinica，2013，34(1)：133-139.
李宇鹏，吴胜和，耿慧丽，等.基于空间矢量的点坝砂体储层构型建模[J]．石油学报，2013，34(1)：133-139.
[6][KG*6/7]He Wenxiang，Wu Shenghe，Tang Yijiang，et al.Detailed architecture analyses of debouch bar in Shengtuo Oilfield，Jiyang Depression[J].Petroleum Exploration and Development，2005，32(5)：42-46.
何文祥，吴胜和，唐义疆，等.河口坝砂体构型精细解剖[J]．石油勘探与开发，2005，32(5)：42-46.
[7]Zhao Xiaoqing，Bao Zhidong，Liu Zongfei，et al.An indepth analysis of reservoir architecture of underwater distributary channel sand bodies in a river dominated delta：A case study of T51 block，Fuyu Oilfield[J].Petroleum Exploration and Development，2013，40(2)：181-187.
赵小庆，鲍志东，刘宗飞，等.河控三角洲水下分流河道砂体储集层构型精细分析——以扶余油田探51区块为例[J]．石油勘探与开发，2013，40(2)：181-187.
[8]Shang Xiaofei，Hou Jiagen，Liu Yuming，et al.Genetic mechanism and distribution patterns of inter(inner)-layers in lacustrine beach-bar sand bodies in Banqiao area，Huanghua Depression[J].Journal of Palaeogeography，2014，16(5)：581-596.
商晓飞，侯加根，刘钰铭，等.黄骅坳陷板桥地区湖相滩坝砂体内部隔(夹)层成因机制与分布样式[J].古地理学报，2014，16(5)：581-596.
[9]Wu Xiaobin，Hou Jiagen，Wang Daxing，et al.Research of single bar dissection of beach-bar sand of the Gangzhong Oilfield in Huanghua Depression[J].Journal of Mineralogy and Petrology，2014，34(5)：89-97.
吴小斌，侯加根，王大兴，等.黄骅坳陷港中油田滩坝砂单一坝精细解剖[J].矿物岩石学，2014，34(3)：89-97.
[10]Zhang Lianliang，Duan Shengqiang，Li Huiguang，et al.Neogene tight oil accumulation conditions and distribution in Zahaquan[J].Special oil and Gas Reservoir，2016，23(2)：36-41.
张连梁，段胜强，李会光，等.扎哈泉地区新近系致密油形成条件与分布特征[J].特种油气藏，2016，23(2)：36-41.
[11]Wang Haifeng.Geological Characteristics of N1 Reservoir in Zahaquan Area，Qaidam Basin[D].Chengdu：Southwest Petroleum University，2013.
王海峰.柴达木盆地扎哈泉地区N1油藏地质特征研究[D].成都：西南石油大学，2013.
[12]Tian Jixian，Zeng Xu，Yi Shiwei，et al.The prediction method of the tight oil reservoirs“sweet spot”in saline lacustrine basin：A case study of the upper Ganchaigou Formation in the Zahaquan district of Qaidam Basin[J].Earth Science Frontiers，2016，23(5)：193-201.
田继先，曾旭，易士威，等.咸化湖盆致密油储层“甜点”预测方法研究：以柴达木盆地扎哈泉地区上干柴沟组为例[J]．地学前缘，2016，23(5)：193-201.
[13]Shang Xiaofei，Hou Jiagen，Sun Futing，et al.Architectural characteristics and sedimentary models of beach-bar sandstone reservoirs：A case study of the Paleogene Shahejie Formation in Banqiao Oilfield，Huanghua Depression[J].Acta Petrolei Sinica，2014，35(6)：1160-1171.
商晓飞，侯加根，孙福亭，等.砂质滩坝储集层内部结构特征及构型模式——以黄骅坳陷板桥油田古近系沙河街组为例[J].石油学报，2014，35(6)：1160-1171.
[14]Tang Wu，Zhong Mihong，Tian Jianhua，et al.Depositional model for lacustrine beach bars of Huangshanjie Formation in Tabei area，Tarim Basin[J].Xinjiang Petroleum Geology，2015，36(3)：299-303.
唐武，仲米虹，田建华，等.塔北地区黄山街组湖盆滩坝砂体沉积模式[J].新疆石油地质，2015，36(3)：299-303.
[15]Zhu Xiaomin，Xin Quanlin，Zhang Jinren，et al.Sedimentary characteristics and models of the beach-bar reservoirs in faulted down lacustrine basins[J].Acta Sedimentologica Sinica，1994，12(2)：20-27.
朱筱敏，信荃麟，张晋仁，等.断陷湖盆滩坝储集体沉积特征及沉积模式[J].沉积学报，1994，12(2)：20-27.
[16]Han Yuanhong，Hao Lewei，Wang Qi，et al.Sedimentary characteristics and types of beach bars deposited in modern times in nearshore of Qinghai Lake[J].Journal of Palaeogeography，2016，18(5)：759-768.
韩元红，郝乐伟，王琪，等.青海湖近岸现代沉积滩坝主要类型及沉积特征[J].古地理学报，2016，18(5)：759-768.
甘公网安备 62010202000678号