Lower Cretaceous dinoflagellate cysts of Exmouth Plateau, Nortwest Australia

Cores from Leg 122, Sites 762 and 763, were sampled at intervals of one sample per 1.5-m section in the Lower Cretaceous sequences. More than 400 samples were studied, most of which contained dinoflagellate cysts, spores, pollen, and various types of palynoclasts. From the entire palynomorph assemblage mainly dinoflagellate cysts were studied to give a stratigraphic outline for the Lower Cretaceous. Stratigraphic units were interpreted in terms of zones in use for the Jurassic and Cretaceous of Australia. At both sites a condensed Valanginian to Aptian sequence and an expanded middle to late Berriasian sequence containing a rich microplankton assemblage were recovered. Sites 762 and 763 can be correlated with each other and with the wells Eendracht-1 and Vinck-1.本数据集的样品采自第122航次762号与763号站位的岩芯，在下白垩统地层序列中以每1.5米岩段1件样品的间隔进行取样。本次研究共分析超过400件样品，其中绝大多数样品均含有沟鞭藻囊孢（dinoflagellate cysts）、孢子、花粉以及各类孢粉屑（palynoclasts）。研究以全部孢粉型组合（palynomorph assemblage）中的沟鞭藻囊孢为主要分析对象，以此构建下白垩统的地层格架。地层单元的划分参照了澳大利亚侏罗系与白垩系通用的生物地层带划分方案。 在两个站位均采获了一套凝缩型凡兰吟阶（Valanginian）至阿普第阶（Aptian）地层，以及一套发育完整的贝里阿斯阶（Berriasian）中晚期地层，该套地层富含微浮游生物组合（microplankton assemblage）。762号与763号站位可实现相互地层对比，同时可与Eendracht-1井及Vinck-1井进行地层对比。