四川盆地川西坳陷上三叠统须家河组储层各向异性地应力评价方法

doi:10.11743/ogg20210416

摘要/Abstract

摘要：

尽管四川盆地川西坳陷上三叠统须家河组砂岩是非常致密的气藏，但是其中一些储层天然裂缝发育，尤其是须二段的优质储层，垂直裂缝或高角度裂缝发育。这导致了岩层和水平主应力的各向异性。对于这类储层如果采用常规的各向同性地应力评价方法，则会高估岩层的实际水平主应力。根据钻井中的溢流、井涌和测试压裂，以及井壁崩落等数据研究了这类储层地应力的新的评价方法，得到了新场气田和合兴场气田的地层压力与地应力实测结果。这些结果表明岩层的天然裂缝对地应力有较大的影响。采用各向异性理论建立了须家河组储层地应力的VTI和HTI模型。含天然裂缝储层的实测数据表明，随着裂缝密度、裂缝倾角和裂缝指示因子的增大，水平主应力和破裂压力减小，这与HTI模型相吻合。结合各向异性模型与天然裂缝、水平主应力和破裂压力的实测数据，得出了适合于须家河组储层特点的地应力预测公式及其对压裂影响的评价方法。

关键词: 裂隙岩层, 水平主应力, 地应力, 各向异性, 水力压裂, 须家河组, 三叠系, 四川盆地

Abstract:

The Triassic Xujiahe Formation sandstones in the western Sichuan Depression are tight gas reservoirs, some of which contain natural fractures, particularly for the gas-rich reservoir in the 2nd member of the Xujiahe Formation (hereafter referred to as Xu 2 Member) with well-developed vertical or high dip angle fractures. Anisotropies of both rocks and horizontal principal stresses are thereby resulted. To calculate in-situ stresses in the naturally fractured formations using conventional methods obtained in the isotropic formation may overestimate the horizontal principal stress. New assessment methods of in-situ stresses in the anisotropic formations are studied in this paper. The in-situ stressess and formation pressures in the Xinchang and Hexinchang gas fields are obtained based on measured data from wellbore influxes, kicks, mini-frac tests and wellbore breakouts.The measured results indicate that natural fractures have a great impact on the in-situ stresses. The theory of anisotropy is applied to establish the in-situ stress models of VTI and HTI for the Xujiahe Formation reservoirs. The measured data in the formations with natural fractures reveal that the horizontal principal stress and formation breakdown pressure decrease as the natural fracture density, dip angle and intensity index increase. This is consistent to the derived HTI model. The assessment methods for in-situ stresses and their impact on hydraulic fracturing are proposed for the Xujiahe Formation reservoirs based on the anisotropic model and the measured data of natural fractures, horizontal stresses and breakdown pressures.

Key words: fissured formation, horizontal principal stress, in-situ stress, anisotropy, hydraulic fracturing, Xujiahe Formation, Triassic, Sichuan Basin

中图分类号:

TE122.2

张金才,范鑫,黄志文,等. 四川盆地川西坳陷上三叠统须家河组储层各向异性地应力评价方法[J]. 石油与天然气地质, 2021, 42(4): 963-972. doi: 10.11743/ogg20210416 Jincai Zhang,Xin Fan,Zhiwen Huang,et al. Assessment of anisotropic in-situ stressses in the Upper Triassic Xujiahe Formation reservoirs in Western Sichuan Depression of the Sichuan Basin[J]. Oil & Gas Geology, 2021, 42(4): 963-972. doi: 10.11743/ogg20210416

图/表 10

表1

表2

图1

图2

图3

图4

图5

图6

图7

图8

参考文献 21

1	Fan X, Huang Z, Liu Z, et al. Complex stress state evaluation and its influence in the hydraulic fracture geometry of the upper Triassic Xujiahe tight formation in the western Sichuan Basin of China[C]. Unconventional Resources Technology Conference(online), Denver, USA, 2020: URTEC-2020-2620-MS.
2	唐自成, 钟大康, 王威, 等. 川东北元坝地区须家河组三段钙屑砂岩孔隙类型及地质意义[J]. 石油与天然气地质, 2019, 40 (5): 1115- 1125.
	Tang Zicheng , Zhong Dakang , Wang Wei , et al. Pore types and geological significance of calcarenaceous sandstones in the 3rd member of Xujiahe Formation in Yuanba area, Northeastern Sichuan Basin[J]. Oil & Gas Geology, 2019, 40 (5): 1115- 1125.
3	王玮, 沈忠民, 裴森奇, 等. 致密砂岩气藏油气轻烃特征及其地质意义: 以四川盆地西北部须家河组气藏为例[J]. 石油实验地质, 2018, 40 (6): 818- 827.
	Wang Wei , Shen Zhongmin , Pei Senqi , et al. Light hydrocarbon chara cteristics of petroleum in a tight sandstone gas reservoir and its geological significance: A case study of the Upper Triassic Xujiahe Formation gas reservoir in the northwestern Sichuan Basin[J]. Petroleum Geology & Experiment, 2018, 40 (6): 818- 827.
4	杜红权, 王威, 时志强, 等. 四川盆地东北部马路背地区上三叠统须家河组天然气地球化学特征及气源[J]. 石油与天然气地质, 2019, 40 (1): 34- 40.
	Du Hongquan , Wang Wei , Shi zhiqiang , et al. Geochemical characteri-stics and source of natural gas of the Upper Triassic Xujiahe Formation in Malubei area, northeastern Sichuan Basin[J]. Oil & Gas Geology, 2019, 40 (1): 34- 40.
5	Hubbert M K , Willis D G . Mechanics of hydraulic fracturing[J]. Petroleum Transactions, 1957, 210 (1): 153- 168.
6	张金才, 亓原昌. 地应力对页岩储层开发的影响与对策[J]. 石油与天然气地质, 2020, 41 (4): 776- 783.
	Zhang Jincai , Qi Yuanchang . Impact of in-situ stresses on shale reservoir development and its countermeasures[J]. Oil & Gas Geology, 2020, 41 (4): 776- 783.
7	李留伟, 吴建军, 龙学, 等. 川西新场构造地应力分布规律研究及其应用[J]. 天然气工业, 2008, 28 (9): 80- 82.
	Li Liuwei , Wu Jianjun , Long Xue , et al. Research on the distribution laws of tectonic in-situ stress in Xinchang Structure (west Sichuan Basin) and their applications[J]. Natural Gas Industry, 2008, 28 (9): 80- 82.
8	谢润成. 川西坳陷须家河组探井地应力解释与井壁稳定性评价[D]. 成都: 成都理工大学, 2009.
	Xie Yuncheng. Stress interpretation and wellbore stability evaluation of Xujiahe Formation of exploration wells in western Sichuan Depression[D]. Chengdu: Chengdu University of Science and Technology, 2009.
9	张守仁, 万天丰, 陈建平. 川西坳陷孝泉-新场地区须家河组二-四段构造应力场模拟及裂缝发育区带预测[J]. 石油与天然气地质, 2004, 25 (1): 70- 74, 80.
	Zhang Shouren , Wang Tianfeng , Chen Jianping . Tectonic stress field modeling and fracture prediction in T₃X^2-4 strata in Xiaoquan-Xingchang area, western Sichuan Depression[J]. Oil & Gas Geology, 2004, 25 (1): 70- 74, 80.
10	Kang H, Zhang J C, Fan X, et al. Cyclic injection to enhance hydraulic fracturing efficiency: Insights from laboratory experiments[J]. Geofluids, 2020, ID 8844293.
11	Daines S R . Prediction of fracture pressures for wildcat wells[J]. Journal of Petroleum Technology, 34 (4): 863- 872. doi: 10.2118/9254-PA
12	Thiercelin M J , Plumb R A . A core-based prediction of lithologic stress contrasts in East Texas Formations[J]. SPE Formation Evaluation, 1994, 9 (4): 251- 258. doi: 10.2118/21847-PA
13	Meng Z P , Zhang J C , Wa ng , R . In-situ stress, pore pressure and stress-dependent permeability in the Southern Qinshui Basin[J]. International Journal of Rock Mechnics and Mining Sciences, 2011, 48 (1): 122- 131. doi: 10.1016/j.ijrmms.2010.10.003
14	张金才, 尹尚先. 页岩油气与煤层气开发的岩石力学与压裂关键技术[J]. 煤炭学报, 2014, 39 (8): 1691- 1699.
	Zhang Jincai , Yin Shangxian . Some technologies of rock mechanics applications and hydraulic fracturing in shale oil, shale gas and coalbed methane[J]. Journal of China Coal Society, 2014, 39 (8): 1691- 1699.
15	Zhang J C , Zheng H R , Wang G L , et al. In-situ stresses, abnormal pore pressures and their impacts on the Triassic Xujiahe gas reservoirs in tectonically active western Sichuan Basin[J]. Marine and Petroleum Geology, 2020, 12, 104708.
16	Zhang J C . Pore pressure prediction from well logs: Methods, modifications, and new approaches[J]. Earth-Science Reviews, 2011, 108, 50- 63. doi: 10.1016/j.earscirev.2011.06.001
17	Amadai B , Pan E . Gravitational stresses in anisotropic rock masses with inclined strata[J]. Internatioanal Journal of Rock Mechnics and Mining Sciences & Geomechanics Abstracts, 1992, 29 (3): 225- 236.
18	Zhang J C . Borehole stability analysis accounting for anisotropies in drilling to weak bedding planes[J]. Internatioanal Journal of Rock Mechnics and Mining Sciences, 2013, 60, 160- 170.
19	Mavko G , Mukerji T , Dvorkin J . The rock physics handbook[M]. Cambridge: Cambridge University Press, 2009.
20	Zhang J J . Applied Petroleum Geomechanics[M]. USA: Gulf Professional Publisher of Elsevier, 2019: 515
21	Peng S P , Zhang J C . Engineering Geology for Underground Rocks[M]. Germany: Springer, 2007: 315

井名	层位	测试段中部深度/m	孔隙压力/MPa	孔隙压力系数
XC12	T₃x⁴⁽⁸⁾	3 679.10	69.14	1.92
XC23	T₃x^4(9-10)	4 022.55	67.69	1.72
XC25	T₃x⁴⁽⁴⁾	3 412.50	63.37	1.89
CX93	T₃ x^4(3-4)	3 410.00	65.97	1.97
X851	T₃x²⁽⁴⁾	4 834.60	80.46	1.70
X853	T₃x²⁽⁷⁾	4 974.63	80.79	1.66
X856	T₃x²⁽⁴⁾	4 837.40	75.99	1.60
X2	T₃x^2(1-4)	4 803.65	71.61	1.52
X3	T₃x²⁽⁵⁾	4 887.70	68.74	1.44
X5	T₃x²⁽⁷⁾	5 158.66	73.98	1.46
X11	T₃x²⁽⁴⁾	4 917.50	68.79	1.43
X10	T₃x^2(4-5)	4 893.08	80.10	1.67
XC8	T₃x^2(2-3)	4 793.69	67.30	1.43

测试方法	井名	层位	测试段中部深度/m	垂向应力/MPa	最小水平主应力/MPa	最大水平主应力/MPa	最小水平主应力梯度/(MPa·km^-1)	最大水平主应力梯度/(MPa·km^-1)
测试压裂	CX560	T₃x⁴⁽⁴⁾	3 524.00	86.30	80.80	-	22.9	-
	CX565	T₃x⁴⁽⁷⁾	3 815.48	93.50	91.20	104.00	23.9	26.1
	CX565	T₃x⁴⁽⁹⁾	3 978.50	97.50	89.70	110.00	22.5	28.8
	XC23	T₃x⁴⁽⁹⁾	4 022.55	98.60	102.00	-	25.4	-
	XC25	T₃x⁴⁽⁹⁾	3 921.00	96.10	96.10	121.30	24.5	30.9
	X10	T₃x²⁽²⁾	4 722.00	115.69	102.70	171.40	21.7	36.3
	X11	T₃x²⁽⁴⁾	4 971.50	121.80	107.40	173.00	21.6	34.8
	X11	T₃x^2(6-8)	5 142.50	125.99	118.40	201.30	23.0	39.1
	X209	T₃x²⁽⁴⁾	4 872.00	119.36	105.50	158.40	21.7	32.5
	XC7	T₃x²⁽⁶⁾	5 151.40	126.21	106.40	168.83	20.7	32.8
成像测井，应力多边形	L150	T₃x²⁽³⁾	4 805.50	117.26	96.07	143.64	20.0	29.9
	X10	T₃x²⁽²⁾	4 692.50	114.97	97.13	144.53	20.7	30.8
	X10	T₃x²⁽³⁾	4 792.90	117.43	98.25	141.87	20.5	29.6
	X10	T₃x²⁽⁴⁾	4 892.10	119.86	101.76	147.25	20.8	30.1
	X10	T₃x²⁽⁴⁾	4 905.30	120.18	103.99	152.55	21.2	31.1
	X10	T₃x²⁽⁶⁾	5 087.50	125.15	106.84	159.24	21.0	31.3
差应变分析	CX560	T₃x²⁽²⁾	4 810.97	125.00	102.00	141.00	21.2	29.3
	CH127	T₃x²⁽¹⁾	4 566.14	111.87	100.65	135.09	22.0	29.6
	CH127	T₃x²⁽²⁾	4 639.29	113.66	104.72	137.60	22.6	29.7
	XC10	T₃x²⁽⁴⁾	4 882.06	119.61	107.93	148.86	22.1	30.5
	XC10	T₃x²⁽⁴⁾	4 884.04	119.66	104.76	140.75	21.4	28.8

[1]	方锐, 蒋裕强, 杨长城, 邓海波, 蒋婵, 洪海涛, 唐松, 谷一凡, 朱讯, 孙莎莎, 蔡光银. 四川盆地侏罗系凉高山组不同岩性组合页岩油赋存状态及可动性[J]. 石油与天然气地质, 2024, 45(3): 752-769.
[2]	何骁, 郑马嘉, 刘勇, 赵群, 石学文, 姜振学, 吴伟, 伍亚, 宁诗坦, 唐相路, 刘达东. 四川盆地“槽-隆”控制下的寒武系筇竹寺组页岩储层特征及其差异性成因[J]. 石油与天然气地质, 2024, 45(2): 420-439.
[3]	张赫驿, 杨帅, 张玺华, 彭瀚霖, 李乾, 陈聪, 高兆龙, 陈安清. 川东地区中二叠统茅口组沉积微相与环境演变[J]. 石油与天然气地质, 2024, 45(2): 457-470.
[4]	潘辉, 蒋裕强, 朱讯, 邓海波, 宋林珂, 王占磊, 李杪, 周亚东, 冯林杰, 袁永亮, 王猛. 河流相致密砂岩气地质甜点评价[J]. 石油与天然气地质, 2024, 45(2): 471-485.
[5]	师良, 范柏江, 李忠厚, 余紫巍, 蔺子瑾, 戴欣洋. 鄂尔多斯盆地中部三叠系延长组7段烃组分的运移分异作用[J]. 石油与天然气地质, 2024, 45(1): 157-168.
[6]	张宝收, 张本健, 汪华, 陈践发, 刘凯旋, 豆霜, 戴鑫, 陈双玲. 四川盆地金秋气田：一个典型以中生界沉积岩为氦源岩的含氦-富氦气田[J]. 石油与天然气地质, 2024, 45(1): 185-199.
[7]	张自力, 乔艳萍, 豆霜, 李堃宇, 钟原, 武鲁亚, 张宝收, 戴鑫, 金鑫, 王斌, 宋金民. 四川盆地蓬莱气区震旦系灯影组二段岩溶古地貌与控储模式[J]. 石油与天然气地质, 2024, 45(1): 200-214.
[8]	王光付, 李凤霞, 王海波, 周彤, 张亚雄, 王濡岳, 李宁, 陈昱辛, 熊晓菲. 四川盆地不同类型页岩气压裂难点和对策[J]. 石油与天然气地质, 2023, 44(6): 1378-1392.
[9]	胡宗全, 王濡岳, 路菁, 冯动军, 刘粤蛟, 申宝剑, 刘忠宝, 王冠平, 何建华. 陆相页岩及其夹层储集特征对比与差异演化模式[J]. 石油与天然气地质, 2023, 44(6): 1393-1404.
[10]	王红岩, 周尚文, 赵群, 施振生, 刘德勋, 焦鹏飞. 川南地区深层页岩气富集特征、勘探开发进展及展望[J]. 石油与天然气地质, 2023, 44(6): 1430-1441.
[11]	边瑞康, 孙川翔, 聂海宽, 刘珠江, 杜伟, 李沛, 王濡岳. 四川盆地东南部五峰组-龙马溪组深层页岩气藏类型、特征及勘探方向[J]. 石油与天然气地质, 2023, 44(6): 1515-1529.
[12]	李双建, 李智, 张磊, 李英强, 孟宪武, 王海军. 四川盆地川西坳陷三叠系盐下超深层油气成藏条件与勘探方向[J]. 石油与天然气地质, 2023, 44(6): 1555-1567.
[13]	曾溅辉, 张亚雄, 张在振, 乔俊程, 王茂云, 陈冬霞, 姚泾利, 丁景辰, 熊亮, 刘亚洲, 赵伟波, 任克博. 致密砂岩气藏复杂气-水关系形成和分布主控因素及分布模式[J]. 石油与天然气地质, 2023, 44(5): 1067-1083.
[14]	赖锦, 白天宇, 肖露, 赵飞, 李栋, 李红斌, 王贵文, 张荣虎. 地应力测井评价方法及其地质与工程意义[J]. 石油与天然气地质, 2023, 44(4): 1033-1043.
[15]	刘昇, 范存辉, 张本健, 张亚, 王尉, 罗冰, 白晓亮. 四川盆地东部中二叠统茅口组孤峰段展布特征及其油气地质意义[J]. 石油与天然气地质, 2023, 44(4): 993-1008.