珠江口盆地番禺4洼古近系文昌组构造变形特征及成因机制

doi:10.19657/j.geoscience.1000-8527.2018.04.11

摘要/Abstract

摘要：

珠江口盆地番禺4洼古近系文昌组构造变形强烈。基于三维地震资料精细解释与编图,对该区主控断裂活动性、沉积中心迁移特征及洼陷结构进行分析,认为番禺4洼古近系文一段沉积期发生了重要的构造事件: 文一段沉积之前,受NW—SE向伸展作用,近NE向断裂强烈活动,沉积中心近NE向展布,北部次洼具有“东西双断”的特征,中部变换带和南部次洼具有“东断西超”的特征;文一段沉积期,EW向断裂强烈活动,多个沉积中心发育,西南斜坡带具有“北断南超”的特征,同时北部次洼、中部变换带和南部次洼依次遭受由强变弱的剥蚀作用。构造变形特征的差异表明,文一段沉积时期是区域应力场方向由NW—SE向近SN向发生顺时针转变的过渡时期。进一步研究表明:太平洋板块及印度板块相对于欧亚板块的汇聚运动使得区域应力场方向发生转变是控制该区构造变形的主因。这一应力体制转变所引起的构造变形不仅发生在番禺4洼,而且在中国东部新生代盆地中广泛存在。

关键词: 珠江口盆地, 番禺4洼, 文昌组, 构造变形, 成因机制

Abstract:

Tectonic deformation of the Paleogene Wenchang Formation in the Panyu 4 sag of Pearl River Estua-ry Basin is intense. According to seismic interpretation, fault activity, migration characteristics of the sedimentation center and depression structural analysis, this study concluded that there was a major tectonic movement in the first stage of the Wenchang Formation. Before that, due to the NW-SE stretching, the intense NE-trending faulting may have led to the NE-trending distribution of sedimentation centers. The northern sub-region has the bipolar (E and W) faulted characteristics. The central and southern sub-regions are featured by faulting in the east and structural overlapping in the west. In the first stage of the Wenchang Formation (during which EW-trending faulting was intense) a EW-trending and a NE-trending sedimentation center were formed. The southwestern slope is featured by faulting in the north and structural overlapping in the south. In the northern sub-region, denudation of the central and southern sub-regions was likely changed from strong to weak. Difference in tectonic deformation indicated that the first stage of the Wenchang Formation was the transition period from NW-to NW-trending extension. Furthermore, the stress regime of the tectonic transform surface was the result of the convergence between the Pacific, India and Eurasian plates. This tectonic phenomenon can be found not only in the Panyu 4 sag, but also in other Cenozoic basins of east China.

Key words: Pearl River Estuary Basin, Panyu 4 sag, Wenchang Formation, structural deformation, tectonicmechanism

中图分类号:

P548
TE121.1

梁杰, 张向涛, 许新明, 罗泽, 吴静. 珠江口盆地番禺4洼古近系文昌组构造变形特征及成因机制[J]. 现代地质, 2018, 32(04): 750-757.

LIANG Jie, ZHANG Xiangtao, XU Xinming, LUO Ze, WU Jing. Characteristics and Formation Mechanism of Structural Deformation in the Paleogene Wenchang Formation in the Panyu 4 Sag, Pearl River Estuary Basin[J]. Geoscience, 2018, 32(04): 750-757.

图/表 7

图1 番禺4洼构造位置图(图中编号代表主控断层编号)

Fig.1 Sketch map showing the structures and location of the Panyu 4 sag in the Pearl River Estuary Basin (the number in the figure representing the number of major faults)

图2 文昌组内部不整合面反射层终止现象(剖面位置见图1中AB)

Fig.2 Seismic reflection terminations of unconformities in the Wenchang Formation of the Panyu 4 sag (seeing Fig.1 for the location of profile AB)

图3 番禺4洼文昌组地层厚度与古断裂叠合分布图

Fig.3 Stratigraphic thickness overlapped with the ancient fault distribution of the Panyu 4 sag

表1 番禺4洼文昌期主干断层要素统计

Table 1 Statistics of major sedimentary-controlling faults of the Wenchang Formation in the Panyu 4 sag

断层	垂直断距/m	延伸长度/km	断层产状		断穿层位	主要活动时期
断层	垂直断距/m	延伸长度/km	走向	倾向	断穿层位	主要活动时期
F1号断层	1 740.9~4 482.5	43.10	NE	NW	T₇₀—Tg	文六段至文一段
F2号断层	62.3~1 475.8	15.86	NNE	SEE	T₈₀—Tg	文六段至文一段
F3号断层	107.8~1 261.1	10.55	NWW	SSW	T₇₀—Tg	文一段至恩平组
F4号断层	83.5~1 091.4	9.61	NWW	SSW	T₇₀—Tg	文一段至恩平组
F5号断层	206.5~2 424.7	20.05	EW	S	T₇₀—Tg	文一段至恩平组
F6号断层	156.7~858.8	10.99	EW	S	T₇₀—Tg	文一段至恩平组

图4 番禺4洼联合地震剖面(剖面位置见图1)

Fig.4 Seismic profile of the Panyu 4 sag (seeing Fig.1 for the profile location)

图5 番禺4洼构造演化剖面(剖面位置见图1中IJ)

Fig.5 Structural evolution profile of the Panyu 4 sag(seeing Fig.1 for the location of profile IJ)

图6 番禺4洼古近系成因机制立体模式图

Fig.6 3D genetic models for the Paleogene in the Panyu 4 sag

参考文献 24

[1]	杨玲, 陈开远, 魏谋杰, 等. 珠江口盆地番禺4洼陷文昌组层序地层划分[J]. 石油天然气学报, 2008, 30(2):187-188.
[2]	衣丽萍, 陈开远, 靳久强, 等. 珠江口盆地番禺4洼陷文昌组沉积充填模式[J]. 新疆石油地质, 2012, 33(4):440-443.
[3]	黄峰, 彭光荣, 温华华, 等. “源-盖”联控成藏模式在番禺4洼的实践[J]. 断块油气田, 2015, 22(3): 278-281.
[4]	朱筱敏, 黄捍东, 代一丁, 等. 珠江口盆地番禺4洼文昌组层序格架与沉积体系研究[J]. 岩性油气藏, 2014, 26(4): 1-8.
[5]	江宁, 全志臻, 张向涛, 等. 珠江口盆地番禺4洼古近系层序地层及储层分布[J]. 石油天然气与开发, 2015, 38(4):23-29.
[6]	王家豪, 刘丽华, 陈胜红, 等. 珠江口盆地恩平凹陷珠琼运动二幕的构造-沉积响应及区域构造意义[J]. 石油学报, 2011, 32(4): 587-595.
[7]	陈汉宗, 吴湘杰, 周蒂, 等. 珠江口盆地中新生代主要断裂特征和动力背景分析[J]. 热带海洋学报, 2005, 24(2): 52-59.
[8]	吴智平, 胡阳, 钟志洪, 等. 珠一坳陷番禺4洼新生代断裂特征及其区域地质动力背景[J]. 中国石油大学学报(自然科学版), 2015, 39(4): 1-9.
[9]	林长松, 高金耀, 虞夏军, 等. 南海北部新生代的构造运动特征[J]. 海洋学报, 2006, 28(4):81-86.
[10]	林长松, 初凤友, 高金耀, 等. 南海新生代的构造运动[J]. 海洋学报, 2007, 29(4):87-96.
[11]	MAGARA K. Thickness of removed sediments paleopore pressure and paleotemperature in southwestern part of Western Canada Basin[J]. AAPG, 1976, 60(6):554-565.
[12]	DOW W G. Kerogen studies and geological interpretations[J]. Journal of Geochemical Exploration, 1977, 7(1):79-99. DOI URL
[13]	VAN HINTE J E. Geohistory analysis-application of micropaleontology in exploration geology[J]. AAPG Bulletin, 1978, 62(3):201-222.
[14]	梁杰, 于福生, 刘国玺, 等. 南堡凹陷分期异向伸展变形叠加特征:来自砂箱物理模拟实验的启示[J]. 现代地质, 2014, 28(1): 139-147.
[15]	王家豪, 王华, 肖敦清, 等. 陆相伸展性盆地二级层序的厘定[J]. 石油学报, 2009, 30(6):869-875. DOI
[16]	冯有良, 周海民, 任建业, 等. 渤海湾盆地东部古近系层序地层及其对构造活动响应[J]. 中国科学(D辑), 2010, 40(10): 1356-1376.
[17]	佟殿君, 任建业, 史双双, 等. 黄骅坳陷新生代关键性构造运动面的确定及盆地演化过程[J]. 油气地质与采收率, 2010, 17(2): 9-13.
[18]	JACKSON E D, SHAW H R, BAGGAR K E. Calculated geochronology and stress field orientation along the Hawaiian chain[J]. Earth and Planetary Science Letters, 1975, 26(10):145-155. DOI URL
[19]	李洪博, 庞雄奇, 彭辉界, 等. 珠江口盆地珠坳陷古隆起控藏特征及有利成藏区定量预测[J]. 现代地质, 2017, 31(4): 802-813.
[20]	NORTHRUP C J, ROYDEN L H, BURCHFIEL B C. Motion of the Pacific plate relative to Eurasia and its potential relation to Cenozoic extrusion along the eastern margin of Eurasia[J]. Geo-logy, 1995, 23(8):719-722.
[21]	VIC Di V, DENNIS V K. Are the Pacific and Indo-Atlantic hotspots fixed? Testing the plate circuit through Antarctica[J]. Earth and Planetary Science Letters, 1999, 170(1): 105-177. DOI URL
[22]	WILLIAM W S, AMY J L, CHRISTIAN K. Paleomagnetic modeling of seamounts near the Hawaiian-Emperor bend[J]. Tectonophysics, 2005, 405(2):121-140. DOI URL
[23]	LEE T Y, LAWVER L A. Cenozoic plate reconstruction of Southeast Asia[J]. Tectonophysics, 1995, 251(1/4):85-138. DOI URL
[24]	REN J, TAMAKI K, LI S, et al. Late Mesozoic and Cenozoic rifting and its dynamic setting in Eastern China and adjacent areas[J]. Tectonophysics, 2002, 344(3/4): 175-205. DOI URL