平衡剖面技术在东海西湖凹陷构造演化研究中的应用
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摘要
选取横跨西湖凹陷的11条典型地震剖面,应用平衡剖面分析技术,计算了西湖凹陷新生代不同构造演化阶段的伸缩率。分析研究表明,西湖凹陷始新统平湖组三四段沉积前处于伸展状态,平湖组三四段至中新统玉泉组沉积时期处于压缩状态,中新统柳浪组沉积至今整体区域沉降。从演化阶段看,始新世中期以前西湖凹陷处于拉张期,始新世中期开始进入挤压期,期间玉泉运动(T30)、花港运动(T20)和龙井运动(T12)3次挤压的强度不断增大。结合凹陷沉积充填结构的分析,西湖凹陷新生代经历了古新世和早中始新世断陷、晚始新世和渐新世坳陷、早中中新世反转和晚中新世至今整体沉降的4个演化阶段。从空间演化上看,不同演化阶段南部和北部伸缩率存在一定的差异,这也是造成西湖凹陷构造南北分块的重要原因。
Eleven typical seismic sections were selected from the Xihu Sag to calculate the extensional and compressional rates of the sag in different tectonic evolutionary stages in Cenozoic,by means of the balanced cross section technique.Results suggeted that the Xihu Sag be in an extension state before the 3rd and 4th members of the Eocene Pinghu Formation was deposited,and in a compression state during the deposition of the 3rd and 4th members of the Eocene Pinghu Formation to the Miocene Yuquan Formation,and had remained in an sinking state since the Miocene Liulang Formation up to present.It,in a tectonic point of view,means that the Sag was extensional before the middle Eocene,and changed into compressional since then,and the compressional strength increased successively from the Yuquan movement(T30),to the Huagang movement(T20) and to the Longjing movement(T12).Based on the depositional architecture of the depression,the tectonic evolution of the Xihu Sag could be divided into four stages,namely the syn-rifting stage from Paleocene to middle Eocene,the post-rifting stage from late Eocene to Oligocene,the inversed stage during early to middle Miocene and the sinking stage since Miocene.The tectonic evolution shows some sort of difference between the south and the north of the Sag in different stages in terms of extensional and compressional rates,that might be the reason for the differentiation of structural appearance in the south and north of the Sag.
Eleven typical seismic sections were selected from the Xihu Sag to calculate the extensional and compressional rates of the sag in different tectonic evolutionary stages in Cenozoic,by means of the balanced cross section technique.Results suggeted that the Xihu Sag be in an extension state before the 3rd and 4th members of the Eocene Pinghu Formation was deposited,and in a compression state during the deposition of the 3rd and 4th members of the Eocene Pinghu Formation to the Miocene Yuquan Formation,and had remained in an sinking state since the Miocene Liulang Formation up to present.It,in a tectonic point of view,means that the Sag was extensional before the middle Eocene,and changed into compressional since then,and the compressional strength increased successively from the Yuquan movement(T30),to the Huagang movement(T20) and to the Longjing movement(T12).Based on the depositional architecture of the depression,the tectonic evolution of the Xihu Sag could be divided into four stages,namely the syn-rifting stage from Paleocene to middle Eocene,the post-rifting stage from late Eocene to Oligocene,the inversed stage during early to middle Miocene and the sinking stage since Miocene.The tectonic evolution shows some sort of difference between the south and the north of the Sag in different stages in terms of extensional and compressional rates,that might be the reason for the differentiation of structural appearance in the south and north of the Sag.
引文
[1]张敏强,钟志洪,夏斌等.东海西湖凹陷中南部晚中新世构造反转与油气运聚[J].中国海上油气,2005,17(2):73-79.
[2]张敏强,徐发,张建培,等.西湖凹陷裂陷期构造样式及其对沉积充填的控制作用[J].海洋地质与第四纪地质,2011,31(5):67-72.
[3]张建培,张涛,刘景彦,等.西湖凹陷反转构造分布与样式[J].海洋石油,2008.28,(4):14-20.
[4]张建培,徐发,钟韬,等.东海陆架盆地西湖凹陷平湖组-花港组层序地层模式及沉积演化[J].海洋地质与第四纪地质,2012,32(1):35-41.
[5]钟志宏,张建培,孙珍,等.西湖凹陷黄岩区地质演化及断层对油气运聚的影响[J].海洋石油,2003,23(5):30-35.
[6]武法东,周平.东海陆架盆地西湖凹陷第三系层序地层与沉积体系分析[M].北京:地质出版社,2000:72-83.
[7]何将启,杨风丽.东海西湖凹陷新生代盆地原型分析[J].海洋石油,2003,12(23):13-20.
[8]王国纯.中国近海盆地的正反转构造及其石油地质意义[J].中国海上油气地质,1995,9(1):33-40.
[9]许薇龄,乐俊英.东海的构造运动及演化[J].海洋地质与第四纪地质,1988,8(1):9-21.
[10]刘卫红,林畅松,郭泽清,等.东海陆架盆地西湖凹陷新生代反转构造样式及其形成机制初探[J].地质科学,2009,44(1):74-87.
[11]周建勋.同沉积挤压盆地构造演化恢复的平衡剖面方法及其应用[J].地球学报,2005,26(2):151-156.
[12]Dahlstrom C.Balanced cross-sections[J].Canadian Journalof Earth Sciences,1969,6(4):743-757.
[13]李三忠,岳云福,高振平,等.伸展盆地区断裂构造特征与成因[J].华南地质与矿产,2003(2):1-7.
[14]Nivaldo D.Release fault:a variety of cross fault in linkedextensional fault systems,in the Sergipe-A Lagoas Basin,N E Brazil[J].Jouanal of Structural Geology,1995,17(5):615-629.
[15]Kelly P G,Peacock D C P,Sanders D J,et al.Selective re-verse-reactivation of normal faults,and deformation aroundreverse-reactivated faults in the Mesozoic of the coast[J].Journal of Structural Geology,1999,21:493-509.
[2]张敏强,徐发,张建培,等.西湖凹陷裂陷期构造样式及其对沉积充填的控制作用[J].海洋地质与第四纪地质,2011,31(5):67-72.
[3]张建培,张涛,刘景彦,等.西湖凹陷反转构造分布与样式[J].海洋石油,2008.28,(4):14-20.
[4]张建培,徐发,钟韬,等.东海陆架盆地西湖凹陷平湖组-花港组层序地层模式及沉积演化[J].海洋地质与第四纪地质,2012,32(1):35-41.
[5]钟志宏,张建培,孙珍,等.西湖凹陷黄岩区地质演化及断层对油气运聚的影响[J].海洋石油,2003,23(5):30-35.
[6]武法东,周平.东海陆架盆地西湖凹陷第三系层序地层与沉积体系分析[M].北京:地质出版社,2000:72-83.
[7]何将启,杨风丽.东海西湖凹陷新生代盆地原型分析[J].海洋石油,2003,12(23):13-20.
[8]王国纯.中国近海盆地的正反转构造及其石油地质意义[J].中国海上油气地质,1995,9(1):33-40.
[9]许薇龄,乐俊英.东海的构造运动及演化[J].海洋地质与第四纪地质,1988,8(1):9-21.
[10]刘卫红,林畅松,郭泽清,等.东海陆架盆地西湖凹陷新生代反转构造样式及其形成机制初探[J].地质科学,2009,44(1):74-87.
[11]周建勋.同沉积挤压盆地构造演化恢复的平衡剖面方法及其应用[J].地球学报,2005,26(2):151-156.
[12]Dahlstrom C.Balanced cross-sections[J].Canadian Journalof Earth Sciences,1969,6(4):743-757.
[13]李三忠,岳云福,高振平,等.伸展盆地区断裂构造特征与成因[J].华南地质与矿产,2003(2):1-7.
[14]Nivaldo D.Release fault:a variety of cross fault in linkedextensional fault systems,in the Sergipe-A Lagoas Basin,N E Brazil[J].Jouanal of Structural Geology,1995,17(5):615-629.
[15]Kelly P G,Peacock D C P,Sanders D J,et al.Selective re-verse-reactivation of normal faults,and deformation aroundreverse-reactivated faults in the Mesozoic of the coast[J].Journal of Structural Geology,1999,21:493-509.
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