1、The South China Sea is a classic example of the marginal basins that typify the margin of Southeast Asia, and one with a relatively complicated tectonic history that has been linked both to the development of the active margins of the Western Pacic and to the tectonics of continental Asia following
2、the IndiaAsia collision starting around 50 Ma. 南海边缘盆地是一个典型的例子,代表的东南亚边缘,它有一个相对复杂的构造史,与西太平洋活动大陆边的发展以及从5000万年前开始的印度-亚洲大陆碰撞所形成的地质构造都密切相关。The tectonics of continental break-up and seaoor spreading have been studied in this area for a signicant period of time, yet our understanding of why the basin formed
3、 in the rst places still remains controversial. 大陆解体的构造和海底传播研究在这一区域已有相当一段时间,但是我们对于该盆地最初的形成的理解仍然是有争议的。Two competing schools have suggested two opposing visions for what caused the basin to open. 两个相互对立的学派对于该盆地的形成提出了两种对立的观点。One of these models relates opening of the South China Sea to the rollback of
4、subduction zones in the Western Pacic and Indonesia that generated regional extensional stresses, so that the South China Sea can be thought of as essentially a large back arc system (Hamilton 1977; Hall 2002). 其中一种观点认为南海的开放与西太平洋和印尼俯冲带产生区域外延的压力有关,因此从本质上来看,南海是是一个大弧后系统(汉密尔顿大厅1977;大厅2002)。In an alterna
5、tive view the South China Sea is envisaged as being the product of the extrusion of a rigid Southeast Asia block linked to indentor tectonics following the India-Asia collision starting in the Eocene (Tapponnier et al. 1982; Leloup et al. 1995). 另一种认为南中国南海被设想为东南亚块挤压的产物,与始新世开始的印度-亚洲大陆碰撞所形成的地质构造相关 (塔波
6、尼尔等人1982;勒卢等人1995年)。This collection of papers represents a signicant new body of data that helps us better understand the geo- physical and geological setting of the South China Sea and associated basins.这个集合的论文展示了一些新的数据可以帮助我们更好地理解中国南海和相关盆地的地球物理和地质背景。 Some of these works are based on study of newly
7、released industrial data sets, while others are purely of academic origin. Taken together they represent a signicant advance in our understanding of the region and help lay the groundwork for the upcoming scientic drilling in the deep-water part of the South China Sea in FebruaryMarch 2014 by the In
8、ternational Ocean Discovery Program (IODP). 其中的一些工作是基于最新出品的工业数据集而展开研究的,而另一些则基于纯粹的学术渊源。加在一起使我们对于该地区的理解有显著的提高,同时也为即将到来的由国际海洋发现计划所提出的在2014年2月至3月南海深水科学钻井奠定基础。Although there remains signicant debate about how strain was accommodated during opening, it is clear that the South China Sea was generated as a
9、result of extension of relatively warm continental crust that had been inuenced by an earlier phase of subduction under southern China known as the Cathaysia arc (Metcalfe 1996).虽然对于在开放期间如何应变压力仍有争论,但是很明显,中国南海的生成是温暖的大陆地壳延伸的结果,这也是受早期阶段被称为华夏弧的华南板块之下俯冲的影响 (梅特卡夫1996)。 This means that the lithosphere that
10、 was affected by extension behaved in a relatively weak and ductile fashion compared to the rifting of more mature continental lithosphere such as in East Africa or Baikal on the edge of the Siberian craton (Clift et al. 2002). The weak, ductile character of the South China lithosphere and especiall
11、y mid-lower crust, has had an important impact on the nature of the rifting in this region, favoring crustal ow (Davis and Kusznir 2004; Sun et al. 2006). 这意味着受扩展行为的影响的岩石圈与西伯利亚克拉通东非或贝加尔湖等边缘的更为成熟的大陆岩石圈相比相对较弱并且样式易伸展。 (克利夫特等人2002)。,华南岩石圈尤其是中、下地壳易延展的特性对这个地区的断裂的性质有一个重要的影响,有利于地壳流(戴维斯和钏路2004;太阳等人2006)。Othe
12、r potential complexities related to the opening of the South China Sea involve the possible involvement of deep-seated mantle plumes (Lei et al. 2009; Liang et al. 2004).中国南海的其他潜在的复杂性可能涉及到深部地幔(雷等人2009;梁等人2004年)。 Although early geophysical studies of the continental margin of southern China suggested
13、 that there might be magmatic underplated bodies under the rifted structure (Kido et al. 2001; Nissen et al. 1995; Wei et al. 2011; Yan et al. 2001) later studies have failed to reveal the tell-tale seaward-dipping reectors that are normally associated with the formation of a rifted volcanic margin
14、(Clift et al. 2001). 虽然早期对于中国南部大陆边缘的地理研究表明在散下结构可能有岩浆underplated (基多等人2001;尼森等人1995;魏2011;严2001年)后来的研究未能揭示泄密seaward-dipping反射,通常与泥盆纪火的形成相关保证金(克利夫特2001)。Nonetheless, many workers continue to believe that elevated mantle thermal anomalies have been involved in the opening of the South China Sea (Shi et
15、 al. 2003; Tu et al. 1991). It is undoubted that magmatism has occurredaway from the sea oor spreading centers during and after the opening of the South China Sea but whether these are plume-related is debated. Signicant volumes of basaltic magma have been mapped in central Vietnam around 8 Ma (Cart
16、er et al. 2000), well after the end of seaoor spreading whether that was at 20 or 15 Ma (Briais et al. 1993; Barckhausen and Roeser 2004), while the passive margin of southern China is also marked by the intrusion of seamounts some of which appeared to be of Quaternary age (Xu et al. 2012).尽管如此,许多工人
17、仍然相信高架地幔热异常涉及了中国南海的开放(史 2003;涂1991年)。无疑,岩浆作用有occurredaway从海底扩张中心期间和中国南海开放之后,就这些是否与羽毛有关值得讨论。相当数量的玄武岩岩浆在越南中部800万平米方圆被绘制 (卡特2000), 在海底传播结束之后,面积便是2000万或者1500万(布里艾 et al . 1993; Barckhausen and Roeser 2004),而中国南方也明显的被动陆缘海的入侵,其中一些似乎是始于第四纪(徐et al . 2012年)。However, these differ signicantly from traditional
18、hotspot tracks linked to classic mantle plumes, like Hawaii or Iceland, because the volumes of magmatism are rather small and the distribution of the magmatism is both widespread and not time-progressive in the traditional fashion of the seamount chain, such as the Emperor- Hawaiian seamount chain.
19、Subsidence analyses of the continental margins also tend to indicate the lack of any signicant thermal anomaly (Wheeler and White 2000;Clift and Lin 2001; Ru and Pigott 1986), which would normally be expected to generate signicant degrees of uplift.然而,这些很大程度上区别于传统热点追踪与经典的地幔羽,像夏威夷或冰岛,因为大量的岩浆作用小,而海底山链
20、的传统方式中岩浆作用的分布广且不随时间累进,如夏威夷天皇海山链。大陆边缘的沉降分析也往往表明缺乏重要的热异常(惠勒和白色2000;克利夫特和林2001;俄罗斯和Pigott 1986),这通常会促进很大程度的提升。 Analysis of the seismic stratigraphy in the South- western South China Sea, adjacent to the Nam Con Son Basin by Li et al. now reveals that post-rift magmatism is dated as Late Miocene to Plio
21、cene in that area effectively synchronous with similar volcanism seen on the South China continental margin. 由李等人对中国南海的西南部毗邻的南昆山盆地地震地层学的分析表明, 晚中新世到上新世,断裂后岩浆作用在那个地区有效地同步类似于中国南部大陆边缘火山活动。The development of basins in the South China Sea has been not only of academic interest but also of economic signica
22、nce. Large oilelds have been known in the region of Brunei and offshore northern Borneo for some time now, as well as within the Tran tensional basins offshore penin- sular Malaysia, in the Gulf of Thailand (Madon and Watts 1998). 中国南海盆地的发展不仅引起了学术兴趣,而且具有重要的经济意义。在文莱和离岸婆罗洲北部的大油田已为人所知有一段时间了,同时为人所知的还有泰国
23、湾马来西亚的离岸桃花江 (马登和美国瓦茨1998)。Although initial attempts to nd hydrocarbons on the passive margin of southern China were not very successful this situation has changed in the last decade so that there is now signicant gas production within the YinggehaiSong Hong Basin, south of Hainan Island in the Qiong
24、dongnan Basin, as well as in the Pearl River Mouth Basin itself (Fig. 1). 虽然最初试图在中国南方的被动陆缘下找到碳氢化合物没有取得一定成效,这种情况在过去十年里已经改变了,因此现在在香港莺歌海盆地、海南岛在琼东南盆地南部以及珠江口盆地有大量的天然气 (图1)。Through mathematical simulation, Lei et al. suggested that formation of the YinggehaiSong Hong Basin was strongly inuenced by the str
25、ikeslip faulting of the Red River Fault. However, its inuence on other parts of the South China Sea is questionable. 通过雷等人进行的数学仿真表明香港莺歌海盆地受到红河断裂的走滑断层很大的影响。然而,对南海的其他部分的影响仍有待考究。Structures closely linked with rifting are imaged on seismic data in Qiongdongnan Basin, which instead favors subduction of a
26、 proto-South China Sea oceanic crust toward NW Borneo during the EoceneEarly Miocene as being necessary to explain rifting and thinning on northern conti- nental margin of South China Sea. 结构与断裂密切关系琼东南盆地地震资料有明确地显示,并没有用始新世早期到中新世期间中国海原南部海洋地壳向婆罗洲西北俯冲带来解释中国南海北部大陆边缘裂谷和变薄的缘由。Some of these basins are parti
27、cularly deep, reaching more than 15 km in the YinggehaiSong Hong Basin (Clift and Sun 2006), as well as in the Baiyun Sag on the edge of the continental shelf offshore southern China. 有些盆地特别深,甚至超过了15公里。比如香港莺歌海盆地(2006年克利夫特,尚恩),以及中国南部大陆架近海的白云凹陷边缘。The vertical tectonics associated with these super deep
28、 basins has often been hard to reconstruct, but there seems to be signicant evidence that not all of the rapid subsidence occurred during the traditional synrift that preceded the onset of seaoor spreading around 30 Ma (Sun et al. 2008; Zhao et al. 2011). 这些超级深盆垂直构造通常难以重建,但似乎有显著的证据表明,并不是所有的快速沉降发生在早于
29、大约3000万年前的海底传播的传统同生裂谷 (尚恩et al . 2008;赵et al . 2011年)。Recognition that rapid subsidence might occur in the post-rift period contradicts traditional models of continental extension (McKenzie 1978) and has led to a variety of potential solutions for understanding the origin of these economically impor
30、tant sags. 我们必须承认的是,快速沉降可能发生断裂后期而不是传统模型的扩展(麦肯齐1978),并且快速沉淀对于理解这些经济上重要的凹陷的起源提供了各种可能的解决方案Although the mechanisms that caused the subsidence still remain obscure, in a new study Xie et al. have now reconstructed the magnitude and timing of rapid subsidence within the Baiyun Sag for the rst time. This d
31、egree of detail now allows us better to correlate these processes with potential tectonic triggers across the region, whether related to tectonic stresses, magmatism or sediment loading. 虽然导致沉降机制仍然模糊,在谢等人开展的一项新的研究中已经首次重建了白云凹陷内快速沉降的量值和调速。现在这种程度的细节让我们更好的在不管是构造应力、岩浆作用或是泥沙装载这些过程中引发整个地区的潜在构造。In a related
32、 study of the Baiyun Sag Wang et al. determined that this basin is not characterized by many long-reaching boundary faults. The shape of the Baiyun Sag is not a typical half-graben. In contrast to the sags in the Northern Depression Zone of the Pearl River Mouth Basin, the Baiyun Sag has been contro
33、lled by two groups of NWW-trending en echelon faults with opposing inclinations.王等人在白云凹陷的相关研究确定,这个盆地不是以很多长期形成的边界断层为特征的。白云凹陷的形状并不是一个典型的半地堑带。与凹陷北部抑郁珠江口盆地的区域相反,白云凹陷已由两组北西西向断裂和斜坡所形成的。 These en echelon faults, together with narrow synclines, partial ower structures and uid diapirs indicate the effects of
34、 left-lateral transtensional stresses, which controlled the distribution of sand bodies during basin opening. 这些雁行断裂以及狭窄的向斜、部分花结构和流体底辟构造显示左旋张扭应力的影响,它控制了砂体在盆地的分布。Zhang and Sun proposed that this basin was a region of thin crust even before the onset of major regional extension during the Oligocene. T
35、hey proposed using an analog modeling method that magma must have played an active part in the rifting process and that this intruded a crust that is more ductile than normal, so resulting in contrasting faulting patterns between the shelf and slope. 张和尚恩提出,这个盆地是一个地区的薄壳即使是在渐新世主要的地区扩展之前。他们提议使用一个模拟建模方
36、法,岩浆在断裂过程中扮演着极其重要的角色,这侵入地壳韧性比正常,所以导致截然不同的货架之间的断裂模式和斜坡。The pre-existing thin crust beneath Baiyun Sag might be related to its Mesozoic tectonic history. By conducting a stratigraphic division and depositional analysis of the Mesozoic in the northern South China Sea, Xu et al. demonstrated that major
37、geological events during basin lling (e.g., seawater withdrawal from the epicontinental region at the end of the Early Jurassic, submarine volca- nism and Late Jurassic-Early Cretaceous uplift of the northern South China Sea shelf) indicate that there had been a collision between a Mesozoic oceanic
38、plate located to the south and the continental crust of southern China in the north. 预先存在的薄壳在白云凹陷可能与中生代构造的历史有关。徐等人在南海北部进行地层划分和沉积分析中表明,盆地充填期间重大地质事件(如海水退出陆缘地区的侏罗纪早期,海底火山就要多年和Jurassic-Early白垩纪末的南海北部大陆架隆起)这些均表明,中生代的海洋之间有碰撞板位于南亚和中国南方的大陆地壳的北方。Basin modeling was pursued in the Qiongdongnan Basin south of H
39、ainan by Zhao et al. who identied three episodes of subsidence, one being rapid during Oligocene regional extension, a subsequent Miocene post-rift phase which was slow and related to thermal subsidence, and then a nal rapid phase starting in the Late Miocene.赵等人中在海南的琼东南盆地南部的盆地建模发现沉降三级,在渐新世地区迅速扩展,随后
40、中新世断裂后阶段是缓慢和相关热沉降,最后是从晚中新世的一个快速阶段。 Analysis of the faults seen in the seismic proles shows that the amount of brittle faulting after 21 Ma is very low and so they conclude that there was no active extension during the post-rift period. 断层在地震剖面的分析表明,脆性断层的数量超过2100万后就会明显降低,所以他们得出结论,没有积极扩展断裂后时期。They inf
41、erred that the younger phase of rapid subsidence was driven by lower crustal thinning linked to a depth-dependent crustal rheology of this basin, a hypothesis supported by gravity data and probably linked to the larger scale ow of ductile lower crust away from the Tibetan Plateau and into Southwest
42、China (Bai et al. 2010; Clark and Royden 2000). Further analysis of the Qiongdongnan Basin was undertaken by Zhang et al. who noted important differences in the structure between the East and West ends of the basin.他们推断,年轻的快速沉降阶段是由下部地壳变薄与深度有关的盆地地壳流变所导致的,该假设是基于从青藏高原到中国西南部的重力数据并且可能与韧性的大规模流动下地壳有关 (白et
43、al . 2010;克拉克和Royden 2000)。张等人对琼东南盆地做了进一步分析,也是他指出了重要的东部和西部之间盆地的结构差异 They concluded that the western basin is strongly inuenced by strike slip faults linked the Red River system and that this area experienced inversion between 30 and 21 Ma. In contrast, the eastern sector is dominated by NE-striking
44、faults before 30 Ma and is typied by a composite symmetrical graben, unlike the asymmetric situation in the West. 他们得出的结论是,西方盆地强烈受到与红色的河流系统息息相关的滑动断层的影响,该地区经历了2100万到3000万年间的演变。与此相反,东部地区主要是3000万年前形成的西北向断裂的影响,体现在一个复合对称地堑,不同于西方的不对称情况。The eastern basin is proposed to be underlain by mantle upwelling and
45、greater heatow whose inuence is not seen further towards the west. This analysis suggests that before 36 Ma the tectonics are dominated by Western Pacific subduction forces, followed by greater inuence from subduction of the proto- South China Sea to the south and increasing degrees of extrusion of
46、Indochina, especially after 30 Ma. 东部盆地很可能是受到地幔上涌和更大的热流的影响,但未对西部盆地造成影响。这一分析表明,在3600万年前,构造学只要是受到西太平洋俯冲地带所支配,紧随其后的是3000万年后的具有更大的影响力的从原始的俯冲南海南部印度支那和增加程度的挤压。The nature of the crust underlying Qiongdongnan Basin was investigated by the study of Qiu et al. who integrated data sets of sedimentary horizons,
47、 wells, seismic reection data and gravity in order to derive the rst integrated crustal scale model of the basin.为了获得第一个综合盆地的地壳规模模型,秋等人对琼东南盆地的地壳底层的沉积、视野、综合数据、集水井,、地震反射数据和重力等性质进行了调查研究。 This compilation showed that the sediment ll is 6 km greater in the west compares to the east, but that the Central
48、Depression contains 10 km more sediment compared to the northern and southern anks. Modeling of the basement under the sediment ll suggests the presence of 24 km thick high-velocity bodies which probably represent under plated igneous bodies emplaced during the nal rifting process, similar to those
49、proposed from further to the east in the Pearl River mouth basin. These are associated with extreme crustal thinning in the central part of the basin (3 km of original crystalline material). 这个编译表明,西方的沉积物填比东方大将近6公里的面积,但中央洼地比北部和南部侧翼多10公里沉积物填。建模下的地下室沉积物填充表明有2 - 4公里厚高速机构的存在,可能代表在镀火成岩体会在最后断裂过程中形成,类似于在珠江口盆地东部的形成情况。这些都与盆地的中部极薄的地壳有关。( 3公里的原始晶体材料)。It is one thing to generate a sedimentary basin by tectonic forces