Geology-engineering integration solution for tight oil exploration of Chang-7 member, Ordos Basin—focusing on scientific well spacing and efficient drilling

FENG Zhangbin1 MA Fujian2 CHEN Bo1 LI Desheng1 CHANG Botao2 LENG Xiangang1 CHAI Huiqiang1 WU Kai2 YANG Yongxing1 WANG Yongkang1 HUANG Yongjie2 DING Li1 LI Zhijun1 LU Qingzhi2 PAN Yuanwei2 HU Zhong2 FU Zairong2 WANG Wei2

(1.Tight Oil Project Team of Changqing Oilfield Company, PetroChina)
(2.Schlumberger (China))

【Abstract】The tight oil reservoirs of the Chang-7 member in the Longdong area, Ordos Basin, are mainly gravity flow sand bodies. The distribution of sand bodies is complex in both vertical and lateral directions, and the thickness of a single sand body is low, which poses a challenge to efficient drilling and production. In this paper, a set of geology-engineering integration methods is proposed, which combines multi-disciplinary knowledge such as near-bit measurement while drilling (MWD) technologies. On the basis of comprehensive geological research, 3D fine geology, reservoir, and geomechanics models are established for selection of well locations, design of factory-like platforms, drilling operations and optimization of geo-steering schemes, so as to design well trajectory scientifically and reasonably, enhance the penetration rate of the sand body during drilling, and ensure higher single well production in later production stage as well as the ultimate long-term accumulative production of the well block. The results show that high-quality reservoirs in the study area are mainly massive clastic-flow sandstones. And the key to improving penetration rate is to use the real-time transmission MWD data, and comprehensively analyze the drilling, well logging and mud logging data to determine the accurate bit location in the sedimentary cycle, so as to determine the geo-steering operation scheme. Under the guidance of this method, two horizontal wells are drilled, whose penetration rates of oil layers are 5%–10% higher than that of the surrounding wells. According to the early-stage numerical simulation based on geology and geomechanics models, combined with scientific well spacing during drilling and production practice, the optimized horizontal well spacing in the study area is finally defined as 400 m.

【Keywords】 Ordos Basin; tight oil; geology-engineering integration; geo-steering; geology modeling;


【Funds】 National Science and Technology Major Project of China (2017ZX05069)

Download this article


    [1] Fu Jinhua, Yu Jian, Xu Liming, Niu Xiaobing, Feng Shengbin, Wang Xiujuan, et al. New progress in exploration and development of tight oil in Ordos Basin and main controlling factors of large-scale enrichment and exploitable capacity [J]. China Petroleum Exploration, 2015, 20 (5): 9–19 (in Chinese).

    [2] Fu Jinhua, Niu Xiaobing, Dan Weidong, Feng Shengbin, Liang Xiaowei, Xin Honggang, et al. The geological characteristics and the progress on exploration and development of shale oil in Chang7 Member of Mesozoic Yanchang Formation, Ordos basin [J]. China Petroleum Exploration, 2019, 24 (5): 601–614 (in Chinese).

    [3] Wang Huizhi, Zhao Weiwei, He Haonan, Feng Jing. Characteristics of tight oil reserviors in Ordos basin-a case study of Chang 7 member in Longdong area [J]. Unconventional Oil & Gas, 2019, 6 (2): 46–55 (in Chinese).

    [4] Zou Caineng, Zhao Zhengzhang, Yang Hua, Fu Jinhua, Zhu Rukai, Yuan Xuanjun, et al. Genetic mechanism and distribution of sandy debris flows in terrestrial lacustrine basin [J]. Acta Sedimentary Sinica, 2009, 27 (6): 1065–1075 (in Chinese).

    [5] Li Xiangbo, Liu Huaqing, Zhang Zhongyi, Yuan Xiaoqi, Wan Yanrong, Niu Haiqing, et al. “Argillaceous parcel” Structure: a direct evidence of debris flow origin of deep-water massive sandstone of Yanchang formation, Upper Triassic, the Ordos Basin [J]. Acta Sedimentologica Sinica, 2014, 32 (4): 42–51 (in Chinese).

    [6] Shanmugam G, Lehtonen L R, Straume T, Syvertsen S E, Hodgkinson R J, Skibeli M. Slump and debris flow dominated upper slope facies in the Cretaceous of the Norwegian and Northern North Seas (61°N–67°N): Implications for sand distribution [J]. AAPG Bulletin, 1994, 78 (6): 910–937.

    [7] Li Shixiang. Effects on petroleum accumulation and genesis of the mesozoic abnormal low pressure in Ordos Basin [D]. Chengdu: Chengdu University of Technology, 2017 (in Chinese).

    [8] Duan Yi, Cao Xixi, Zhao Yang, Zhang Zhongyi, Yu Yongjin, Wu Yingzhong, et al. Characteristics and Formation Mechanism of Mesozoic Underpressured Reservoir in Ordos Basin [J]. Earth Science—Journal of China University of Geosciences, 2014, 39 (3): 341–349 (in Chinese).

    [9] Xie Jun, Qiu Kaibin, Zhong Bing, Pan Yuanwei, Shi Xuewen, Wang Lizhi. Construction of a 3D geomechanical model for development of a shale gas reservoir in Sichuan basin [J]. SPE Drilling & Completion, 2017, 33 (4). SPE-187828-PA.

    [10] Zhang Kuangsheng, Tang Meirong, Du Xianfei, Ma Bing, Qiu Kaibin, Wang Lizhi, et al. Application of integrated geology and geomechanics to stimulation optimization workflow to maximize well potential in a tight oil reservoir, Ordos basin, Northern Central China [J]. American Rock Mechanics Association, 2019, August 28. ARMA 19-2187.

    [11] Liang Baosheng, Du Meilin, Christina Goloway, Robert Hammond, Pablo Paez Yanez, Tan Tran. Subsurface well spacing optimization in the Permian basin [C]. URTeC: 2671346. Unconventional Resource Technology Conference, 2017.

    [12] Cao Richard, Li Ruijian, Alejandro Girardi, Nitin Chowdhury, Chen Chaohui. Well Interference and optimization well spacing for Wolfcamp development at Permian basin [C]. URTeC: 2691962. Unconventional Resource Technology Conference, 2017.

    [13] Tang Yula, Liang Baosheng. Reservoir surveillance pilot study for Midland basin tight oil spacing optmization [C]. SPE-175533-MS. SPE Liquid-Rich Basins Conference North American, 2015.

    [14] Sun Xiangcan, Tong Xiaoguang, Zhang Guangya, Wen Zhixin, Wang Zhaoming. Permean Wolfcamp tight oil trapping characteristics and controls [J]. Journal of Southwest Petroleum University: Science & Technology Edition, 2018, 40 (1): 47–58 (in Chinese).

    [15] Wei Yu, Kamy Sepehrnoori. Optimization of well spacing for Bakken tight oil reservoirs [C]. URTec: 1922108. Unconventional Resource Technology Conference, 2014.

    [16] Robert Flook, Will Alexander, Dave List, Bob Sencenbaugh, Breck Enoch, Aaron J Wheeler, et al. At-bit inclination, gamma, and Imaging system tracks productive zone in complex geology [J]. Journal of Petroleum Technology, 2013, 65 (3): 30–32.

    [17] Aaron J. Wheeler, Thomas Billings, Allan Rennie, Rick Lee, Robert Little, Cornelis Huiszoon, et al. The introduction of an at-bit natural gamma ray imaging tool reduces risk associated with real-time geosteering decisions in coalbed methane horizontal wells [C]. SPWLA-2012-167. SPWLA 53rd Annual Logging Symposium, 2012.

    [18] Wu Qi. Application and development of geosteering and rotary steerable techniques [M]. Beijing: Petroleum Industry Press, 2012 (in Chinese).

    [19] Liang Xing, Xu Jinbin, Liu Cheng, Jiao Yajun, Shu Honglin, Chen Anhuan, et al. Geosteering technology based on geological and engineering integration for horizontal wells in Zhaotong National Shale Gas Demonstration Zone [J]. China Petroleum Exploration, 2019, 24 (2): 226–232 (in Chinese).

    [20] Wu Zongguo, Liang Xing, Dong Jianyi, Li Zhaofeng, Zhang Zhao, Wang Gaocheng, et al. Application of 3D geosteering in geology-engineering integration practice [J]. China Petroleum Exploration, 2017, 22 (1): 89–98 (in Chinese).

This Article


CN: 11-5215/TE

Vol 25, No. 02, Pages 155-168

March 2020


Article Outline


  • 0 Introduction
  • 1 Geological research
  • 2 Geology-engineering integration modeling and numerical reservoir simulation
  • 3 Drilling operation and geo-steering
  • 4 Conclusions and prospects
  • References