Carbonate delta drift: A new sediment drift type
Carbonate delta drift: A new sediment drift type
复制标题
碳酸盐岩三角洲漂移：一种新的沉积物漂移类型
DOI：
10.1016/j.margeo.2018.04.011
复制
发表时间：
2018
期刊：
影响因子：
2.9
通讯作者：
Jovane
中科院分区：
文献类型：
--
作者：
Lüdmann;Betzler;Eberli;Reolid;Reijmer;Bialik;Alvarez-Zarkikian;Alonso-Garcia;Blatter;Haffen;Horozal;Jovane
根据IODP 359远征队的高分辨率反射地震和岩心数据，我们提出了一种新的与碳酸盐台地斜坡相关的水道漂移类型，我们称之为三角洲漂移。像河流三角洲一样，它由几个堆叠的裂片组成，并连接到一个点源。三角洲漂流体沉积在连接马尔代夫碳酸盐岩地台内海与公海的两个门户的出口处。沟渠起到集中和加速水流的作用；被夹带的物质沉积在水流放松的河口。这些叶状钙质沉积物一定是在持续的水流作用下形成的。沉积物供给相对丰富且持续，平均沉积速率为17 cm ka−1。两个三角洲漂移区分别占342和384 km2；沉积起伏度约为500 m。它们具有s型斜形反射图案，具有特定的凸向上弯曲的前庭。在马尔代夫，漂移的开始标志着从海平面控制到洋流逐渐主导的沉积制度的转变。这一重大事件发生在约13 Ma以前的塞拉瓦里系，导致碳酸盐岩台地部分被淹没，形成了浅海道。最初的河岸封闭地形类似于一个“空桶”几何形状，迅速被漂移沉积物填满，这些沉积物沉积并进入盆地。因此，三角洲漂流体的沉积环境在顶部由深水（bbb500）向浅水环境转变，其颗粒大小总体呈粗化上升趋势，顶部存在浅水大型底栖有孔虫。
Based on high-resolution reflection seismic and core data from IODP Expedition 359 we present a new channel-related drift type attached to a carbonate platform slope, which we termed delta drift. Like a river delta, it is comprised of several stacked lobes and connected to a point source. The delta drifts were deposited at the exit of two gateways that connect the Inner Sea of the Maldives carbonate platform with the open ocean. The channels served as conduits focusing and accelerating the water flow; Entrained material was deposited at their mouth where the flows relaxed. The lobe-shaped calcareous sediment drifts must have formed under persistent water through flow. Sediment supply was relatively high and continuous, resulting in an average sedimentation rate of 17 cm ka−1. The two delta drifts occupy 342 and 384 km2, respectively; with a depositional relief of approximately 500 m. They have a sigmoidal clinoform reflection pattern with a particular convex upward bending of the foresets. In the Maldives the drift onset marks the transition from a sea-level controlled to a progressively current dominated depositional regime. This major event occurred in the Serravallian about 13 Ma ago, leading to the partial drowning of the carbonate platform and the creation of shallow seaways. The initial bank-enclosed topography resembles an “empty bucket” geometry which is rapidly filled by the drift sediments that aggrade and prograde into the basin. Thereby the depositional environment of the delta drifts changes from deep water (>500) to shallow-water conditions at their topsets, indicated by the overall coarsening upward trend in grain size and the presence of shallow water large benthic foraminifers at their top.
登录
查看更多内容
DOI：
10.1016/s0070-4571(08)10009-7
发表时间：
2008
期刊：
Developments in sedimentology
影响因子：
--
作者：
D. Stow;Sally E. Hunter;D. Wilkinson;F. Hernández‐Molina
通讯作者：
D. Stow;Sally E. Hunter;D. Wilkinson;F. Hernández‐Molina
DOI：
10.1007/978-1-4757-3296-2_7
发表时间：
2020-02
期刊：
Definitions
影响因子：
--
作者：
Nina Zahrai
通讯作者：
Nina Zahrai
影响因子：
3.9
作者：
Betzler, C.;Eberli, G. P.;Yao, Z.
通讯作者：
Yao, Z.
DOI：
10.1016/s0070-4571(08)10013-9
发表时间：
2008
期刊：
Developments in sedimentology
影响因子：
--
作者：
D. Stow;J. Faugères
通讯作者：
D. Stow;J. Faugères
影响因子：
3.2
作者：
C. Betzler;J. Fürstenau;T. Lüdmann;Christian Hübscher;S. Lindhorst;A. Paul;J. Reijmer;A. Droxler
通讯作者：
C. Betzler;J. Fürstenau;T. Lüdmann;Christian Hübscher;S. Lindhorst;A. Paul;J. Reijmer;A. Droxler