Analysis of sedimentary environment of the upper Cenozoic in Niigata Sedimentary Basin

新泻沉积盆地发育褶皱、厚的新生代层序。在重新研究地层学的基础上，从岩相和生物相两方面分析了新生代层序的沉积环境。以下结果具有重要的地层学意义。1)东-久比基地区：上中新统至更新世Tamugigawa组与Shobudani组相交叉，以浊积岩为主。2)西kubiki - Otari地区：Tenguhara-yama火山碎屑被认为与Nanatani组相关，与Nanatani组至下Teradomari组相关的Nambayama组中部穿插。对于沉积环境，以下结果是重要的。1)晚中新世至更新世，东-库比基地区的沉积盆地分异和来自隆升省的粗碎屑供给发生。盆地由槽型盆地和地槽型盆地组成。2)从沉积构造和质地特征出发，研究了柏崎地区荒滨沙丘的形成过程。古沙丘沙的结构特征与全新世沙丘具有相同的风运沙特征。3) Teradomari组模式区域的Argonautidae， Dephalopoda为新泻沉积盆地首次发现。这一现象对古海洋环境即暖流流入的考虑尤为重要。

The Folded and thick Cenozoic sequence is distributed in the Niigata Sedimentary Basin. On the bases of stratigraphy reinvestigated, the sedimentary environment of the Cenozoic sequence was analyzed from the lithofacies and biofacies.The following results are important stratigraphically. 1) Higashi-Kubiki district: The Upper Miocene to Pleiocene Tamugigawa Formation, mainly composed of turbidite sediments, is interfingerred with the Shobudani Formation, mainly composed of massive mudstone.2) Nishi-Kubiki - Otari district: The Tenguhara-yama Volcanic Clasts, considerred to be correlated to the Nanatani Formation, is intercalated within the middle part of the Nambayama Formation correlated with the Nanatani to Lower Teradomari Formations.For the sedimentary environment, the following resilts are important.1) In Higashi-Kubiki district, the differentiation of sedimentary basin and the supply of coarse clastics from the provinance uplifted were taken place from the late Miocene to Pleiocene time. The basin was composed of the trough-type basin and horst.2) Formative process of Arahama Sand Dune in the Kashiwazaki district are investigated based on the sedimentary structure and textural property. The textural propertiy of sand of paleo-sand dune shows the characteristics of sand transported by wind same as the Holocene sand dune.3) Argonautidae, Dephalopoda from the type locality of Teradomari Formation is the first occurrence in the Niigata Sedimentary Basin. The occurrence is particulary important to the consideration of the paleo-oceanic environment, that is, the inflow of the warm current.