Analogue experiments on the piggyback propagation in northwestern Sichuan and latest propagation in its deeps
-
摘要: 近年来油气勘探揭示了川西前陆北段油气资源的巨大潜力，但因受控于龙门山—川西前陆系统多期构造活动和山前带深埋藏等，川西前陆山前隐伏构造带含油气构造模型解释具有明显的多解性和不确定性。基于川西北前陆原型与实验室砂箱构造物理模型间几何学—运动学—动力学相似性原理，通过两组川西前陆北段扩展变形构造物理模型对比实验（即标准模型实验和断坪—断坡模型实验），揭示川西冲断褶皱带—前陆盆地受控于中、下三叠统膏盐和下寒武统泥岩2套主滑脱层系，晚中生代—新生代呈现出分层式前陆扩展变形特征，基底断坪—断坡结构对川西北前陆深层冲断—冲起构造的控制影响作用最为明显。进一步结合川西北前陆双鱼石地区三维地震解释资料，揭示川西北前展式扩展晚期变形的古生界隐伏冲断—冲起构造构成了川西北深层主要的勘探潜力区。Abstract: Recent explorations reveal a great potential for oil and gas resources in the northwestern Sichuan foreland basin. However, constrained by multi-phase tectonic activities of the Longmenshan-West Sichuan foreland system and the deep burial of the piedmont belt, there remain many uncertainties in the interpretation of petroleum structure models in the foreland concealed tectonic belt. Based on the geometry-kinematics-dynamic similarity theory between the foreland prototype of the northwestern Sichuan and the sandbox analogue model, two groups of controlled experiments were carried out (including standard scaled experiments and analogue experiments with a ramp-flat structure). The fold-thrust belt and foreland basin of the western Sichuan are controlled by two sets of main detachments of the Middle-Lower Triassic gypsum salt and the Lower Cambrian mudstone, leading the layered-style propagation to the foreland in the Late-Middle Cenozoic. The ramp-flat structure plays a profound influence on deep thrust and pop-up structures in the northwestern Sichuan foreland basin. Analogue results combined with seismic interpretation of the northwestern Sichuan illustrates that the main exploration potential may rely on the Paleozoic blind thrust and pop-up structures caused by the latest propagation to the northwestern Sichuan foreland basin.
-
图 2 川西北段砂箱物理模型边界条件示意
Figure 2. Boundary conditions for sandbox model of northwestern Sichuan Basin
图 3 川西北段地层比例标准(a)和断坪—断坡结构(b)模型实验演化及其解释
①-⑨.挤压缩短量逐渐增加导致造山带楔形体物质序次变形过程，⑨.模型挤压结果构造解释图。图中冲断层及其相关褶皱结构按照形成演化序列标注，T6a等.浅部滑脱层系逆冲断层，T6b等.深部前展式逆断层，T6b'.深部反冲断层
Figure 3. Evolution and interpretation of standard scaled (a)and the pre-existing ramp-flat structure(b)experiment of northwestern Sichuan Basin
图 4 川西北段砂箱物理模型模拟楔形体几何学特征
Figure 4. Geometric features of wedges in sandbox analogue experiments of northwestern Sichuan Basin
图 6 川西北前陆区地震测线及其深部冲起结构构造解释对比
测线位置见图 1。
Figure 6. Seismic lines of the foreland zone in northwestern Sichuan Basin and the interpretation of their thrust and pop-up structures
表 1 砂箱物理模型模拟实验比例系数特征
Table 1. Scale coefficient for sandbox physical model of simulation experiments
参数 物理模型(M) 自然实例(N) 比例系数(M/N) 长度(L) /m 8.5×10-1 1.7×105 L*=5×10-6 缩短量(D)/m 0.30 6.0×104 D*=5×10-6 内聚力 20~100 Pa 5~20 MPa 重力加速度(g)/(m·s-2) 9.81 9.81 g* =1.0 密度(石英砂)/(kg·m-3) 1 550 2 200 ρ*1=0.70 密度(玻璃珠)/(kg·m-3) 1 370 2 400 ρ*2=0.57 密度(硅胶)/(kg·m-3) 960 2 300 ρ*3=0.42 应力(σ) σ* =ρ*g*L* =6.60×10-6 动力黏度(η)/(Pa·s) 2.1×104 1.7×1019 η* =1.24×10-15 时间 1×105 s tN=tM/t*=8.44 Ma t* =η*/σ* =3.76×10-10 速率 0.003 mm/s 7.1 km/Myr 注：tN，tM分别代表自然实际和实验模型中的时间跨度，t*为实验—实例时间比例系数，η*为动力黏度比例系数。表中部分参数来源于文献[23]，计算公式参考文献[4]。 
下载: 导出CSV
-
[1] BUTLER R W H, BOND C E, COOPER M A, et al. Interpreting structural geometry in fold-thrust belts: why style matters[J]. Journal of Structural Geology, 2018, 114: 251-273. doi: 10.1016/j.jsg.2018.06.019 [2] GRAVELEAU F, MALAVIEILLE J, DOMINGUEZ S. Experimental modelling of orogenic wedges: a review[J]. Tectonophysics, 2012, 538-540: 1-66. doi: 10.1016/j.tecto.2012.01.027 [3] DUERTO L, MCCLAY K. The role of syntectonic sedimentation in the evolution of doubly vergent thrust wedges and foreland folds[J]. Marine and Petroleum Geology, 2009, 26(7): 1051-1069. doi: 10.1016/j.marpetgeo.2008.07.004 [4] DOOLEY T P, JACKSON M P A, HUDEC M R. Breakout of squeezed stocks: dispersal of roof fragments, source of extrusive salt and interaction with regional thrust faults[J]. Basin Research, 2015, 27(1): 3-25. doi: 10.1111/bre.12056 [5] 邓宾, 黄瑞, 马华灵, 等. "从源到汇": 褶皱冲断带-前陆盆地系统砂箱物理模型浅表作用研究[J]. 大地构造与成矿学, 2018, 42(3): 431-444. https://www.cnki.com.cn/Article/CJFDTOTAL-DGYK201803002.htmDENG Bin, HUANG Rui, MA Hualing, et al. "Source to sink": a review of tectonics-erosion-sedimentation interactions in the analogue experiments of accretionary wedge[J]. Geotectonica et Metallogenia, 2018, 42(3): 431-444. https://www.cnki.com.cn/Article/CJFDTOTAL-DGYK201803002.htm [6] 刘树根, 罗志立, 赵锡奎, 等. 试论中国西部陆内俯冲型前陆盆地的基本特征[J]. 石油与天然气地质, 2005, 26(1): 37-48. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200501006.htmLIU Shugen, LUO Zhili, ZHAO Xikui, et al. Discussion on essential characteristics of intracontinental-subduction type foreland basins in western China[J]. Oil & Gas Geology, 2005, 26(1): 37-48. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200501006.htm [7] 刘和甫, 梁慧社, 蔡立国, 等. 川西龙门山冲断系构造样式与前陆盆地演化[J]. 地质学报, 1994, 68(2): 101-118. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE199402000.htmLIU Hefu, LIANG Huishe, CAI Liguo, et al. Structural styles of the Longmenshan thrust belt and evolution of the foreland basin in western Sichuan Province, China[J]. Acta Geologica Sinica, 1994, 68(2): 101-118. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE199402000.htm [8] 杨克明. 川西坳陷须家河组天然气成藏模式探讨[J]. 石油与天然气地质, 2006, 27(6): 786-793. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200606010.htmYANG Keming. Gas reservoiring mode in Xujiahe Formation of Western Sichuan Depression[J]. Oil & Gas Geology, 2006, 27(6): 786-793. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200606010.htm [9] JIA Dong, WEI Guoqi, CHEN Zhuxin, et al. Longmen Shan fold-thrust belt and its relation to the western Sichuan Basin in central China: new insights from hydrocarbon exploration[J]. AAPG Bulletin, 2006, 90(9): 1425-1447. doi: 10.1306/03230605076 [10] 徐旭辉, 方成名, 刘金连, 等. 中国中西部山前构造变形结构分带模式与油气[J]. 石油实验地质, 2019, 41(6): 779-790. doi: 10.11781/sysydz201906779XU Xuhui, FANG Chengming, LIU Jinlian, et al. Deformation zoning model of piedmont thrust, western China, and its petroleum response[J]. Petroleum Geology & Experiment, 2019, 41(6): 779-790. doi: 10.11781/sysydz201906779 [11] 刘树根, 孙玮, 王国芝, 等. 四川叠合盆地油气富集原因剖析[J]. 成都理工大学学报(自然科学版), 2013, 40(5): 481-497. https://www.cnki.com.cn/Article/CJFDTOTAL-CDLG201305001.htmLIU Shugen, SUN Wei, WANG Guozhi, et al. Analysis of causes of oil and gas accumulation in superimposed Sichuan Basin of China[J]. Journal of Chengdu University of Technology (Science & Technology Edition), 2013, 40(5): 481-497. https://www.cnki.com.cn/Article/CJFDTOTAL-CDLG201305001.htm [12] 张本健, 谢继容, 尹宏, 等. 四川盆地西部龙门山地区中二叠统碳酸盐岩储层特征及勘探方向[J]. 天然气工业, 2018, 38(2): 33-42. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG201802006.htmZHANG Benjian, XIE Jirong, YIN Hong, et al. Characteristics and exploration direction of the Middle Permian carbonate reservoirs in the Longmenshan Mountain areas, western Sichuan Basin[J]. Natural Gas Industry, 2018, 38(2): 33-42. https://www.cnki.com.cn/Article/CJFDTOTAL-TRQG201802006.htm [13] 刘树根, 李智武, 曹俊兴, 等. 龙门山陆内复合造山带的四维结构构造特征[J]. 地质科学, 2009, 44(4): 1151-1180. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKX200904012.htmLIU Shugen, LI Zhiwu, CAO Junxing, et al. 4-D textural and structural characteristics of Longmen intracontinental composite orogenic belt, southwest, China[J]. Chinese Journal of Geology, 2009, 44(4): 1151-1180. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKX200904012.htm [14] LIU Shugen, DENG Bin, LI Zhiwu, et al. Architecture of basin-mountain systems and their influences on gas distribution: a case study from the Sichuan Basin, South China[J]. Journal of Asian Earth Sciences, 2012, 47: 204-215. doi: 10.1016/j.jseaes.2011.10.012 [15] DENG Bin, LIU Shugen, JANSA L, et al. Sedimentary record of Late Triassic transpressional tectonics of the Longmenshan thrust belt, SW China[J]. Journal of Asian Earth Sciences, 2012, 48: 43-55. doi: 10.1016/j.jseaes.2011.12.019 [16] 胡烨, 陈迎宾, 王彦青, 等. 川西坳陷回龙构造雷口坡组天然气成藏条件[J]. 特种油气藏, 2018, 25(1): 46-51. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201801010.htmHU Ye, CHENYingbin, WANG Yanqing, et al. Naturalgas accumulation conditions in LeiKoupo Formation of Huilongstructure, Western Sichuan Depression[J]. Special Oil & Gas Reservoirs, 2018, 25(1): 46-51. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201801010.htm [17] 陈竹新, 贾东, 魏国齐, 等. 龙门山北段冲断前锋构造带特征[J]. 石油学报, 2008, 29(5): 657-662. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB200805006.htmCHEN Zhuxin, JIA Dong, WEI Guoqi, et al. Characteristics of thrust structures in the northern Longmenshan front belt[J]. Acta Petrolei Sinica, 2008, 29(5): 657-662. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB200805006.htm [18] LIU Shugen, DENG Bin, JANSA L, et al. The Early Cambrian Mianyang-Changning intracratonic sag and its control on petroleum accumulation in the Sichuan Basin, China[J]. Geofluids, 2017, 2017: 6740892. [19] CHAPPLE W M. Mechanics of thin-skinned fold-and-thrust belts[J]. GSA Bulletin, 1978, 89(8): 1189-1198. [20] DAVIS D, SUPPE J, DAHLEN F A. Mechanics of fold-and-thrust belts and accretionary wedges[J]. Journal of Geophysical Research: Solid Earth, 1983, 88(B2): 1153-1172. [21] DAHLEN F A, SUPPE J, DAVIS D. Mechanics of fold-and-thrust belts and accretionary wedges: cohesive coulomb theory[J]. Journal of Geophysical Research: Solid Earth, 1984, 89(B12): 10087-10101. [22] 邓宾, 赵高平, 万元博, 等. 褶皱冲断带构造砂箱物理模型研究进展[J]. 大地构造与成矿学, 2016, 40(3): 446-464. https://www.cnki.com.cn/Article/CJFDTOTAL-DGYK201603004.htmDENG Bin, ZHAO Gaoping, WAN Yuanbo, et al. A review of tecto-nic sandbox modeling of fold-and-thrust belt[J]. Geotectonica et Metallogenia, 2016, 40(3): 446-464. https://www.cnki.com.cn/Article/CJFDTOTAL-DGYK201603004.htm [23] DENG Bin, JIANG Lei, ZHAO Gaoping, et al. Insights into the velocity-dependent geometry and internal strain in accretionary wedges from analogue models[J]. Geological Magazine, 2018, 155(5): 1089-1104. [24] BUITER S J H. A review of brittle compressional wedge models[J]. Tectonophysics, 2012, 530-531: 1-17. [25] WEIJERMARS R, JACKSON M P A, VENDEVILLE B. Rheological and tectonic modeling of salt provinces[J]. Tectonophysics, 1993, 217(1/2): 143-174. [26] LOHRMANN J, KUKOWSKI N, ADAM J, et al. The impact of analogue material properties on the geometry, kinematics, and dynamics of convergent sand wedges[J]. Journal of Structural Geology, 2003, 25(10): 1691-1711. [27] KOYI H A, HESSAMI K, TEIXELL A. Epicenter distribution and magnitude of earthquakes in fold-thrust belts: insights from Sandbox Models[J]. Geophysical Research Letters, 2000, 27(2): 273-276. [28] KOYI H A, MAILLOT B. Tectonic thickening of hanging-wall units over a ramp[J]. Journal of Structural Geology, 2007, 29(6): 924-932. [29] BONINI M, SOKOUTIS D, MULUGETA G, et al. Modelling hanging wall accommodation above rigid thrust ramps[J]. Journal of Structural Geology, 2000, 22(8): 1165-1179. [30] MCCLAY K R. Glossary of thrust tectonic terms[M]//Thrust Tectonics. London: Chapman and Hall, 1992: 419-433. [31] ALSOP G I, WEINBERGER R, MARCO S. Distinguishing thrust sequences in gravity-driven fold and thrust belts[J]. Journal of Structural Geology, 2018, 109: 99-119. [32] 管树巍, 李本亮, 何登发, 等. 构造楔形体的识别与勘探: 以准噶尔盆地南缘为例[J]. 地学前缘, 2009, 16(3): 129-137. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201901017.htmGUAN Shuwei, LI Benliang, HE Dengfa, et al. Recognition and exploration of structural wedges: a case study of the southern margin of Junggar Basin[J]. Earth Science Frontier, 2009, 16(3): 129-137. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201901017.htm [33] BONINI M. Passive roof thrusting and forelandward fold propagation in scaled brittle-ductile physical models of thrust wedges[J]. Journal of Geophysical Research: Solid Earth, 2001, 106(B2): 2291-2311. [34] BONINI M. Deformation patterns and structural vergence in brittle-ductile thrust wedges: an additional analogue modelling perspective[J]. Journal of Structural Geology, 2007, 29(1): 141-158. [35] NILFOUROUSHAN F, PYSKLYWEC R, CRUDEN A. Sensitivity analysis of numerical scaled models of fold-and-thrust belts to granular material cohesion variation and comparison with analog experiments[J]. Tectonophysics, 2012, 526-529: 196-206. [36] 邓涛, 李勇. 龙门山前陆盆地南段须五段页岩气富集条件及有利区评价[J]. 特种油气藏, 2018, 25(4): 51-56. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201804010.htmDENG Tao, LIYong. Shalegas enrichment condition and favorable area evaluation of the Xu5 Member in the southern section of Longmenshan Foreland Basin[J]. Special Oil & Gas Reservoirs, 2018, 25(4): 51-56. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201804010.htm [37] ZHANG Peizhen, WEN Xueze, SHEN Zhengkang, et al. Oblique, high-angle, listric-reverse faulting and associated development of strain: the Wenchuan Earthquake of May 12, 2008, Sichuan, China[J]. Annual Review of Earth and Planetary Sciences, 2010, 38(1): 353-382. -
点击查看大图
图(6) / 表(1)
计量
- 文章访问数: 439
- HTML全文浏览量: 73
- PDF下载量: 128
- 被引次数: 0
苏公网安备32021102000780号