The Lower Cretaceous (Berriasian and Valanginian) in NW Germany
The Lower Cretaceous (Berriasian and Valanginian) in NW Germany
复制标题
德国西北部的下白垩统（贝里亚阶和瓦兰吉阶）
DOI：
10.1006/cres.1996.0010
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发表时间：
1996
影响因子：
2.1
通讯作者：
J. Mutterlose
中科院分区：
文献类型：
--
作者：
F. Elstner;J. Mutterlose
摘要描述了德国西北部贝里亚阶和下瓦兰阶的非海相沉积序列。介形虫的地层分布允许这个间隔被细分为10个生物带，可用于在西北德国盆地中部的区域对比。三种介形虫分类群（Fabanella ansata、Cypridea阿尔塔福尔摩沙和致密厚壳介）可用于德国、丹麦、法国和英国之间的区域间相关。Katzberg段的中部，即F.安萨塔，允许与英格兰南部的下普尔贝克，巴黎盆地和布隆奈的相关性。该物种的首次出现可用于定义波特兰/Purbeck边界。介形虫组合分类学内容的波动反映了盐度的变化。在最早的Berriasian（Munder Formation）和最早的Valanginian（Osterwald Member）期间，半咸水条件主导了沉积。晚贝里阿斯期奥伯恩基兴段的沉积物是在淡水条件下沉积的。一个短暂的海侵标志着中期Berriasian（基地Wealden 4）。Valanginian中期的Platylenticeras层表明恢复到完全的海洋条件。
Abstract The non-marine sedimentary successions of the Berriasian and lower Valanginian of NW Germany are described. The stratigraphical distribution of ostracods allow this interval to be subdivided into 10 biozones, which can be used for regional correlation in the central part of the NW German Basin. Three ostracod taxa ( Fabanella ansata, Cypridea alta formosa and Pachycytheridea compacta ) can be used for interregional correlation between Germany, Denmark, France and England. The middle part of the Katzberg Member, which yields F. ansata , allows correlation with the Lower Purbeck of S England, the Paris Basin, and the Boulonnais. The first occurrence of this species can be used to define the Portland/Purbeck boundary. Fluctuations in the taxonomic content of ostracod assemblages reflect changes in salinity. Brackish conditions dominated deposition during the earliest Berriasian (Munder Formation) and earliest Valanginian (Osterwald Member). Sediments of the late Berriasian Obernkirchen Member were deposited under freshwater conditions. A short-lived marine transgression marked the mid Berriasian (base Wealden 4). The Platylenticeras Beds of mid-Valanginian age indicate a return to fully marine conditions.