基于重电资料的敦煌盆地地质结构特征研究

doi:10.3969/j.issn.1672-7703.2019.03.010

摘要/Abstract

摘要： 敦煌盆地整体叠置于塔里木板块东部的敦煌地块上，其油气勘探与研究程度很低，研究敦煌盆地的盆地结构，包括断裂展布、构造格局及基底埋深等，可为进一步勘探综合研究提供地质依据。在对研究区野外露头岩石物性资料、钻测井测试结果统计分析的基础上，结合其他地质资料，总结了岩石、地层密度与电性变化规律。采用层状模型延拓技术消除地形引起的电性畸变效应，使大地电磁反演结果更为精确。采用水平总梯度技术对敦煌盆地的重力资料提取了重力线性梯级带，以此强化盆内断层的线性特征。采用Parker反演法对基底深度进行反演分析。研究结果表明，敦煌盆地发育3套密度层和电性层，盆内区域断裂控制了凹凸相间的构造格局，五墩凹陷基底埋深最大，为最有利的沉积中心。

关键词: 敦煌盆地, 重力异常, 电性结构, 断裂展布, 基底结构

Abstract: The Dunhuang Basin is generally superimposed on Dunhuang block in the eastern part of Tarim plate. So far, it has been less explored and investigated. Understanding the basin structure, including fault distribution, structural pattern and basement depth, can provide a geological basis for further comprehensive study on exploration. Based on the physical properties of outcrops, drilling/logging results and other geological data, the variations of rock, formation density and electrical properties were identified. The layered model was combined with the continuation technique to eliminate electric distortion caused by terrains, thus deriving more accurate electromagetic inversion results. The gravity linear-gradient zones were extracted from gravity data using the total horizontal gradient technique to enhance the linear characteristics of faults within the basin. The basement depth was analyzed with the Parker inversion method. The results show that:in the Dunhuang Basin, there are three sets of density and electrical layers. The regional faults control the structural pattern of alternate uplifts and sags. And Wudun sag has the deepest basement, which is the most favorable depocenter.

Key words: Dunhuang Basin, gravity anomaly, electrical structure, fault distribution, basement structure

中图分类号:

郭涛, 李竹强, 胡加山, 林治模, 尹克敏, 冯国志, 魏敏. 基于重电资料的敦煌盆地地质结构特征研究[J]. 中国石油勘探, 2019, 24(3): 369-376.

Guo Tao, Li Zhuqiang, Hu Jiashan, Lin Zhimo, Yin Kemin, Feng Guozhi, Wei Min. Study on geological structure of the Dunhuang Basin based on gravity and electric data[J]. China Petroleum Exploration, 2019, 24(3): 369-376.

参考文献

[1] 赵澄林,季汉成,胡爱梅,韩春元,马晓昌,周劲松.敦煌盆地群侏罗系石油地质研究[M].北京:石油工业出版社,2002. Zhao Chenglin, Ji Hancheng, Hu Aimei, Han Chunyuan, Ma Xiaochang, Zhou Jinsong. Petroleum geology of Jurassic in Dunhuang Basin[M]. Beijing:Petroleum industry press, 2002.
[2] 袁永真,张小博,张鹏辉,钟清.西拉木伦河断裂重、磁、电特征分析[J].物探化探计算技术,2015,39(6):1209-1304. Yuan Yongzhen, Zhang Xiaobo, Zhang Penghui,Zhong Qing.An analysis of gravity magnetic and electric characteristics of the Xar Moron River fault[J]. Geophysical and Geochemical Exploration,2015,39(6):1299-1304.
[3] 冯旭亮,王万银,李建国,赵斌,赵楠.大中条地区重磁场特征及其断裂分布与构造单元[J].地质与勘探,2015,51(3):563-572. Feng Xuliang, Wang Wanyin, Li Jianguo, Zhao Bin, Zhao Nan. Distribution of faults and division of tectonic units in the Great Zhongtiao area of southern Shanxi Province derived from gravity and magnetic anomaly data[J]. Geology and Exploration, 2015,51(3):563-572.
[4] 张交东,杨晓勇,刘成斋,张丽莉,李冰,徐亚,等.大别山北缘深部结构的高精度重磁电震解析[J].地球物理学报,2012,55(7):2292-2306. Zhang Jiaodong, Yang Xiaoyong, Liu Chengzhai, Zhang Lili, Li Bing, Xu Ya, et al. The fine deep structure of the northern margin of the Dabie Orogenic Belt from gravity-magnetic-electrical-seismic combination survey[J]. Chinese Journal of Geophysics, 2012,55(7):2292-2306.
[5] 王鑫,张景发,姜文亮,蒋洪波,田甜,高敏,等.郯庐断裂带南段重力异常及不同深度的横向构造特征[J].地震地质,2016,38(2):370-385. Wang Xin, Zhang Jingfa, Jiang Wenliang, Jiang Hongbo, Tian Tian, Gao Min, et al. Transverse structures features of different depths derived from bouguer gravity anomalies in the southern segment of Tan-Lu fault zone[J]. Seismology and Geology,2016,38(2):370-385.
[6] 胡加山,胡贤根,崔世凌.东营凹陷典型剖面重磁电震综合解释方法研究[J].石油物探,2009,48(4):401-406. Hu Jiashan, Hu Xiangen, Cui Shiling. Gravity-magnetic-electric-seismic integrated interpretation method for typical profile of Dongying sag[J]. Geophysical Prospecting for Petroleum,2009,48(4):401-406.
[7] 俞建宝,吴永栓,刘立群.也门47区块重震联合解释技术的应用[J].勘探地球物理进展,2007,30(3):214-218. Yu Jianbao, Wu Yongshuan, Liu Liqun. Joint gravitational and seismic data interpretation technique and its application in Block 47,Yemen[J]. Progress in Exploration Geophysics,2007,30(3):214-218.
[8] 王谦身,滕吉文,张永谦,皮姣龙.鄂尔多斯-中秦岭-四川东部的重力异常场与深部地壳结构[J].地球物理学报,2015,58(2),532-541. Wang Qianshen,Teng Jiwen,Zhang Yongqian,Pi Jiaolong.Gravity anomalies and deep crustal structure of the Ordos Basin middle Qinling orogeny-eastern Sichuan Basin[J]. Chinese Journal of Geophysics, 2015,58(2):532-541.
[9] 鲁宝亮,王谱珺,张功成,王万银.南海区域断裂特征及基底构造格局[J].地球物理学进展,2015,30(4):1544-4553. Lu Baoliang, Wang Pujun, Zhang Gongcheng, Wang Wanyin.Characteristic of regional fractures in South China Sea and its basement tectonic framework[J]. Progress in Geophysics, 2015,30(4):1544-4553.
[10] 刘志龙,叶高峰,魏文博,金胜.海拉尔盆地中-上地壳电性结构特征研究[J].地球物理学报,2015,58(12):4425-4435. Liu Zhilong, Ye Gaofeng, Wei Wenbo, Jin Sheng. Study of the central-upper crust electrical structure of Hailar Basin[J]. Chinese Journal of Geophysics, 2015,58(12):4425-4435.
[11] 王绪本,李永年,高永才.大地电磁测深二维地形影响极其校正方法研究[J].物探化探计算技术,1999,21(4):327-332. Wang Xuben, Li Yongnian, Gao Yongcai. Two dimensional topographic responses in magneto telluric sounding and its correction methods[J]. Computing Techniques for Geophysical and Geochemical Exploration,1999,21(4):327-332.
[12] 薛国强,闫述,陈卫营.电磁测深数据地形影响的快速校正[J].地球物理学报,2016,59(12):4408-4413. Xue Guoqiang, Yan Shu, Chen Weiying. A fast topographic correction method for electromagnetic data[J]. Chinese Journal of Geophysics,2016,59(12):4408-4413.
[13] 董浩,魏文博,叶高峰,金胜,景建恩.基于有限差分法正演的带地形三维大地电磁反演方法[J].地球物理学报,2014,57(3):939-952. Dong Hao, Wei Wenbo, Ye Gaofeng, Jin Sheng, Jing Jian'en. Study of three-dimensional magnetotelluric inversion including inversion including surface topography based on finite-difference method[J]. Chinese Journal of Geophysics, 2014,57(3):939-952.
[14] 雷达.地形起伏下CSAMT二维正反演研究与应用[J].地球物理学报,2010,53(4):982-993. Lei Da. Studies and applications of 2-D CSAMT modeling and invertion with a diploe source and topography[J]. Chinese Journal of Geophysics, 2010,53(4):982-993.
[15] 王志宏,山科社.电磁法测量的地形影响及校正方法[J].物探与化探,2011,35(3):364-367. Wang Zhihong,Shan Keshe.Effects and correction of topography in magnetotelluric sounding[J]. Geophysical and Geochemical Exploration, 2011,35(3):364-367.
[16] 霍光谱,胡祥云,黄一凡,韩波.带地形的大地电磁各向异性二维模拟及实例对比分析[J].地球物理学报,2015,58(12):4696-4708. Huo Guangpu, Hu Xiangyun, Huang Yifan, Han Bo. MT modeling for two-dimensional anisotropic conductivity structure with topography and example of comparative analyses[J]. Chinese Journal of Geophysics, 2015,58(12):4696-4708.
[17] 赵希刚,吴汉宁,柏冠军,王靖华.重磁异常解释断裂构造的处理方法及图示技术[J].地球物理学进展,2008,23(2):414-421. Zhao Xigang, Wu Hanning, Bai Guanjun,Wang Jinghua. Magnetic and gravity data processing method and imaging techniques for faulted structure interpretation[J]. Progress in Geophysics, 2008,23(2):414-421.
[18] 王万银,邱之云,杨永,史维皎.位场边缘识别方法研究进展[J].地球物理学进展,2010,25(1):196-209. Wang Wanyin, Qiu Zhiyun, Yang Yong,Shi Weijiao. Some advance in the edge recognition of the potential field[J]. Progress in Geophysics, 2010,25(1):196-209.
[19] 王彦国,张凤旭,王祝文,孟令顺,张瑾.位场归一化差分法的边界检测技术[J].吉林大学学报:地球科学版,2013,43(2):592-601. Wang Yanguo, Zhang Fengxu, Wang Zhuwen, Meng Lingshun,Zhang Jin. Edge detection of potential field using normalized differential[J]. Journal of Jilin University:Earth Science Edition, 2013,43(2):592-601.
[20] 马国庆,杜晓娟,李丽丽.位场数据边界识别的新方法——增强型水平导数法[J].地球物理学进展,2013,28(1):402-407. Ma Guoqing, Du Xiaojuan, Li Lili. New edge detection of potential field data-enhanced horizontal derivative method[J]. Progress in Geophysics, 2013,28(1):402-407.
[21] 陈青,袁炳强,董云鹏,程顺有,张春灌.断裂识别新方法及其在肯尼亚Tana凹陷中的应用[J].西北大学学报:自然科学版,2013,43(4):599-605. Chen Qing, Yuan Bingqiang, Dong Yunpeng, Cheng Shunyou, Zhang Chunguan. The new methods to study fault strcture by gravity data and application to Tana sag in Kenya[J]. Journal of Northwest University:Natural Science Edition, 2013,43(4):599-605.