Seismic responses and forming conditions of the Oligocene shelf-edge delta and deepwater fan system in Changchang-Heshan sag,northern South China Sea
Zhu Xiaomin1, Ge Jiawang1, Song Shuang1, Wang Ruiliang2, Yuan Lizhong2, Liu Jun2
1 College of Geosciences,China University of Petroleum(Beijing),Beijing 102249; 2 The Research Institute of Shengzhen Branch, CNOOC Limited,Guangzhou 510240,Guangdong;
Abstract：Changchang-Heshan sag is a deepwater sedimentary basin and located on the continental slope in the northern South China Sea. It is an important strategic exploration block after oil and gas exploration breakthrough in Baiyun and Liwan sags in adjacent deep-water regions. Guided by the theory of classic sequence stratigraphy and based on the characteristics of the seismic reflection and stratigraphic cycles,the Oligocene Zhuhai Formation could be divided into six third-order sequences(namely ZHSQ1,ZHSQ2,ZHSQ3,ZHSQ4,ZHSQ5 and ZHSQ6 from bottom to top). Six types of seismic facies,including high continuity,weak-medium amplitude sheet seismic facies of shelf,S-shaped and oblique progradational seismic facies of shelf-edge,variable amplitude,medium continuity,mound-shaped bidirectional overlap seismic facies of continental slope and so on,are identified within the Zhuhai Formation. S-shaped and oblique progradational seismic facies represents shelf-edge delta,while mound-shaped bidirectional overlap seismic facies represents deepwater fan. The shelf-edge delta and deepwater fan systems have been changed with the formation condition of tectonic and sea level variation. The results show that during the deposition of ZHSQ1 and ZHSQ2,the boundary faults of the sag were active and the shelf slope-break belt was controlled by these faults. The depositional system was limited by the assemblage of shallow marine and proximal deltas. The basin stepped into depression stage and the boundary faults were inactive during the depositional period from ZHSQ3 to ZHSQ6;meanwhile,the shelf slope-break belt was characterized by the sedimentary slope break belts,migrated forward to the central sea direction and became larger all the time under the control of relative sea level falling with stable material source supply from the ancient Pearl River. At the same time,the shelf-edge delta prograded with distance nearly 20,km,and the slope got increasingly steep. Therefore,the occurrence frequency and scale of deep-water fans in front of the shelf-edge delta increased from early to late,and the position became closer to the shelf-edge delta.
Zhu Xiaomin,Ge Jiawang,Song Shuang et al. Seismic responses and forming conditions of the Oligocene shelf-edge delta and deepwater fan system in Changchang-Heshan sag,northern South China Sea[J]. JOPC, 2016, 18(3): 367-380.
[1] 陈泓君,黄文凯,吴峧岐. 2013. 南海西北部晚第四纪典型地震相—沉积相特征. 海洋地质前沿,29(11):1-7. [Chen H J,Huang W K,Wu J Q. 2013. Typical seismic and sedimentary facies of the late Quaternary in the Northwestern South China Sea. Marine Geology Frontiers,29(11):1-7] [2] 崔莎莎,何家雄,陈胜红,邹和平,崔洁. 2009. 珠江口盆地发育演化特征及其油气成藏地质条件. 天然气地球科学, 20(3):384-391. [Cui S S,He J X,Chen S H,Zou H P,Cui J. 2009. Development characteristics of Pearl River Mouth Basin and its geological conditions for oil and gas accumulation. Natural Gas Geoscience,20(3):384-391] [3] 黄维,汪品先. 2006. 渐新世以来的南海沉积量及其分布. 中国科学(D辑:地球科学),36(9):822-829. [Huang W,Wang P X. 2006. The sediment volume and distribution of the South China Sea from the Oligocene. China Science(series D,Earth science),36(9):822-829] [4] 纪沫,杨海长,曾清波. 2015. 南海北部深水区鹤山凹陷构造演化及其油气地质意义. 长江大学学报(自然科学版), 12(17):19-23. [Ji M,Yang H C,Zeng Q B. 2015. Structural evolution and the significance of oil and gas analysis of Heshan Sag of the Deep-water area in the North of South China Sea. Journal of Yangtze University(Natural Science Edition). 12(17):19-23] [5] 林鹤鸣,施和生. 2014. 珠江口盆地白云—荔湾深水区油气成藏条件及勘探方向. 天然气工业,34(5):29-36. [Lin H M,Shi H S. 2014. Hydrocarbon accumulation conditions and exploration direction of Baiyun-Liwan deep water area in the Pearl River Mouth Basin. Natural Gas Industry,34(5):29-36] [6] 刘军. 2013. 南海北部超深水区鹤山凹陷古近系沉积充填特征分析. 石油天然气学报,35(7):15-18. [Liu J. 2013. Depositional filling characteristics of Paleogene in Heshan sag of Deepwater area in the Northern South China Sea. Journal of Oil and Gas Technology,35(7):15-18] [7] 柳保军,庞雄,颜承志,刘军,连世勇,何敏,申俊. 2011a. 珠江口盆地白云深水区渐新世—中新世陆架坡折带演化及油气勘探意义. 石油学报,32(2):234-242. [Liu B J,Pang X,Yan C Z,Liu J,Lian S Y,He M,Shen J. 2011a. Evolution of the Oligocene-Miocene shelf slope break zone in the Baiyun deep-water area of the Pearl River Mouth Basin and its significance in oil-gas exploration. Acta Petrolei Sinica,32(2):234-242] [8] 柳保军,庞雄,颜承志,连世勇,刘军,何敏,申俊,韩晋阳,李元平. 2011b. 珠江口盆地白云深水区沉积充填演化及控制因素分析. 中国海上油气,23(1):19-25. [Liu B J,Pang X,Yan C Z,Lian S Y,Liu J,He M,Shen J,Han J Y,Li Y P. 2011b. Analysis of depositional evolution and its controls on Baiyun deep-water area,Pearl River Mouth basin. China Offshore Oil and Gas,23(1):19-25] [9] 马俊明,薛林福,付少英,赵聪俐,李文博,2013. 南海神狐海域地震—沉积相分析与沉积环境演化. 世界地质,32(2):359-365. [Ma J M,Xue L F,Fu S Y,Zhao C L,Li W B,2013. Seismic-sedimentary facies analysis and evolution of sedimentary environment in Shenhu area,South China Sea. Global Geology,32(2):359-365] [10] 米立军,张功成,沈怀磊,刘震,郭瑞,钟锴,田继先. 2008. 珠江口盆地深水区白云凹陷始新统—下渐新统沉积特征. 石油学报,29(1):29-34. [Mi L J,Zhang G C,Shen H L,Liu Z,Guo R,Zhong K,Tian J X. 2008. Eocene-Lower Oligocene sedimentation characteristics of Baiyun sag in the deep water area of Pearl River Mouth Basin. Acta Petrolei Sinica,29(1):29-34] [11] 庞雄,陈长民,彭大钧,周蒂,陈红汉. 2007a. 南海珠江深水扇系统及油气. 北京:科学出版社,23-49. [Pang X,Chen C M,Peng D J,Zhou D,Chen H H. 2007a. Pearl River deep-water fan system and petroleum in South China Sea. Beijing:Science Press,23-49] [12] 庞雄,陈长民,邵磊,王成善,朱明,何敏,申俊,连世勇,吴湘杰. 2007b. 白云运动:南海北部渐新统—中新统重大地质事件及其意义. 地质论评, 53(2):145-151. [Pang X,Chen C M,Shao L,Wang C S,Zhu M,He M,Shen J,Lian S Y,Wu X J. 2007b. Baiyun Movement,a Great Tectonic Event Boundary in the Northern South China the Oligocene-Miocene and its implications. Geological Review, 53(2):145-151] [13] 冉怀江,林畅松,代一丁,秦成岗,吴伟,张俞,乔阳. 2012. 陆架坡折带识别及其对沉积层序的控制作用. 石油地球物理勘探, 47(A01):125-128. [Ran H J,Lin C S,Dai Y D,Qin C G,Wu W,Zhang Y,Qiao Y. 2012. Shelf break zone identification and its control on sedimentary sequence formations. Oil Geophysical Prospecting, 47(A01):125-128] [14] 邵磊,李献华,汪品先,翦知湣,韦刚健,庞雄,刘颖. 2004. 南海渐新世以来构造演化的沉积记录: ODP1148站深海沉积物中的证据. 地球科学进展,9(4):539-544. [Shao L,Li X H,Wang P X,Jian Z M,Wei G J,Pang X,Liu Y. 2004. Sedimentary record of the tectonic evolution of the South China Sea since the Oligocene,evidence from deep sea sediments of ODP Site 1148. Advance in Earth Science,9(4):539-544] [15] 施和生,柳保军,颜承志,朱明,庞雄,秦成岗. 2010. 珠江口盆地白云—荔湾深水区油气成藏条件及勘探潜力. 中国海上油气,22(6):369-374. [Shi H S,Liu B J,Yan C Z,Zhu M,Pang X,Qin C G. 2010. Hydrocarbon accumulation conditions and exploration potential in Baiyun-Liwan deepwater area,Pearl River Month basin. China Offshore Oil and Gas,22(6):369-374] [16] 石宁,袁立忠,刘军,宋建虎,张建强,刘莹. 2013. 鹤山凹陷烃源岩分布特征研究. 断块油气田,20(5):556-559. [Shi N,Yuan L Z,Liu J,Song J H,Zhang J Q,Liu Y. 2013. Distribution characteristics of hydrocarbon source rock in Heshan Sag. Fault-Block Oil and Gas Field, 20(5):556-559] [17] 孙珍,钟志洪,周蒂,夏斌,丘学林,曾佐勋,姜建群. 2006. 南海的发育机制研究:相似模拟证据. 中国科学(D辑地球科学), 36(9):797-810. [Sun Z,Zhong Z H,Zhou D,Xia B,Qiu X L,Zeng Z X,Jiang J Q. 2006. The South China Sea mechanism research:Evidence from analog simulation. Science in China(series D, Earth Science), 36(9):797-810] [18] 唐武,王英民,黄志超,王琳,邓彦涛,何永垚,周兴海,王丹. 2012. 琼东南盆地南部深水区中新统层序地层地震相与沉积演化特征. 海相油气地质, 17(2):20-25. [Tang W,Wang Y M,Huang Z C,Wang L,Deng Y T,He Y Y,Zhou X H,Wang D. 2012. Seismic sequence facies strata and sedimentary evolution characteristics of Miocene in the Deep-water Region,Southern Qiongdongnan Basin. Marine Origin Petroleum Geology, 17(2):20-25] [19] 王永凤,王英民,李冬,徐强. 2011. 陆架边缘三角洲沉积特征研究及其油气意义. 海洋地质前沿, 27(7):28-33. [Wang Y F,Wang Y M,Li D,Xu Q. 2011. Depositional characteristics of shelf margin deltas and their petroleum significance. Marine Geology Frontiers,27(7):28-33] [20] 吴景富,徐强,祝彦贺. 2010. 南海白云凹陷深水区渐新世—中新世陆架边缘三角洲形成及演化. 地球科学(中国地质大学学报),35(4):681-690. [Wu J F,Xu Q,Zhu Y H. 2010. Generation and evolution of the shelf-edge delta in Oligocene and Miocene of Baiyun Sag in the South China Sea. Earth Science(Journal of China University of Geosciences),35(4):681-690] [21] 徐怀大,王世风,陈开远. 1990. 地震地层学解释基础. 湖北武汉: 中国地质大学出版社,12-145. [Xu H D,Wang S F,Chen K Y. 1990. The Basis of Seismic Sequence Interpretation. Wuhan, Hubei: China University of Geoscience Press,12-145] [22] 徐强,王英民,吕明,王丹,李冬,王永凤. 2011. 陆架边缘三角洲在层序地层格架中的识别及其意义: 以南海白云凹陷为例. 石油与天然气地质,32(54):733-742. [Xu Q,Wang Y M,Lü M,Wang D,Li D,Wang Y F. 2011. Identification of the shelf margin delta in sequence stratigraphic frameworks and its significance: A case study of the Baiyun Sag,South China Sea. Oil and Gas Geology,32(54):733-742] [23] 曾清波,陈国俊,张功成,纪沫,韩银学,郭帅,王龙颖. 2015. 珠江口盆地深水区珠海组陆架边缘三角洲特征及其意义. 沉积学报,33(3):595-606. [Zeng Q B,Chen G J,Zhang G C,Ji M,Han Y X,Guo S,Wang L Y. 2015. The shelf margin delta feature and its significance in Zhuhai Formation of deep water area,Pearl River Mouth Basin. Acta Sedimentologica Sinica,33(3):595-606] [24] 张功成,米立军,屈红军,冯杨伟,范玉海. 2011. 全球深水盆地群分布格局与油气特征. 石油学报,32(1):369-378. [Zhang G C,Mi L J,Qu H J,Feng Y W,Fan Y H. 2011. A basic distributional framework of global deepwater basins and hydrocarbon characteristics. Acta Petrolei Sinica,32(1):369-378] [25] 张功成,米立军,屈红军,张厚和,谢晓军,胡圣标,张义娜. 中国海域深水区油气地质. 石油学报,2013,34(S2):1-14. [Zhang G C,Mi L J,Qu H J,Zhang H H,Xie X J,Hu S B,Zhang Y N. Petroleum geology of deep-water areas in offshore China. Acta Petrolei Sinica,34(S2):1-14] [26] 赵中贤,周蒂,廖杰. 2009. 珠江口盆地第三纪古地理及沉积演化. 热带海洋学报, 28(6):52-60. [Zhao Z X,Zhou D,Liao J. 2009. Tertiary paleogeography and depositional evolution in the Pearl River Mouth Basin of the northern South China Sea. Journal of Tropical Oceanography,28(6):52-60] [27] 朱筱敏. 2008. 层序地层学. 山东东营:中国石油大学出版社,11-25. [Zhu X M. 2008. Sequence Stratigraphy. Dongying,Shandong:China University of Petroleum Press,11-25] [28] 朱伟林,钟锴,李友川,徐强,房殿勇. 2012. 南海北部深水区油气成藏与勘探. 科学通报,57(20):1833-1841. [Zhu W L,Zhong K,Li Y C,Xu Q,Fang D Y. 2012. Oil and gas accumulation and exploration of the deep-water area of the Northern South China Sea. Chinese Science Bulletin,57(20):1833-1841] [29] 祝彦贺,朱伟林,徐强,吴景富. 2011. 珠江口盆地13.8,Ma陆架边缘三角洲与陆坡深水扇的“源-汇”关系. 中南大学学报(自然科学版), 42(12):3827-3834. [Zhu Y H,Zhu W L,Xu Q,Wu J F. 2011. Sedimentary response to shelf-edge delta and slope deep-water fan in 13.8,Ma of Miocene epoch in Pearl River Mouth Basin. Journal of Central South University(Science and Technology),42(12):3827-3834] [30] Brown L F,Fisher W L. 1980. Seismic stratigraphic interpretation and petroleum exploration. AAPG,Continuing Education Course Note Series,16:1-18. [31] Carvajal C,Steel R. 2009. Shelf-edge architecture and bypass of sand to deep water: Influence of shelf-edge processes,sea level,and sediment supply. Journal of Sedimentary Research,79(9):652-672. [32] Catuneanu O. 2006. Principles of sequence stratigraphy. Amsterdam:Elsevier Press,1-369. [33] Mitchum R M. 1977. Seismic stratigraphy and global changes of sea level,part Ⅱ,Glossary of terms used seismic stratigraphy. AAPG Memoir,26:205-212. [34] Muto T,Steel R J. 2002. In defense of shelf-edge delta development during falling and lowstand of relative sea level. The Journal of Geology,110(4):421-436. [35] Plink-Bjorklund P,Ron Steel. 2002. Sea-level fall below the shelf edge,without basin-floor fans. Geology,30(2):115-118. [36] Porebski S J,Steel R J. 2003. Shelf-margin deltas:Their stratigraphic significance and relation to deepwater sands. Earth-Science Reviews,62(3-4):283-326. [37] Shannon P M,Stoker M S,Praeg D. 2005. Sequence stratigraphic analysis in deep-water,under-filled NW European passive margin basins. Marine and Petroleum Geology,22(9-10):1185-1200. [38] Uroza C A,Steel R J. 2008. A highstand shelf-margin delta system from the Eocene of West Spitsbergen,Norway. Sedimentary Geology,203(3-4):229-245. [39] Vail P R. 1977. Seismic recognition of depositional facies on slopes and rises. AAPG Bulletin,61(5):837.
