Tephrostratigraphy of the Nanatani to Uonuma Formations of 13Ma to 1Ma in the Niigata region, central Japan.
Tephrostratigraphy of the Nanatani to Uonuma Formations of 13Ma to 1Ma in the Niigata region, central Japan.
复制标题
日本中部新泻地区 13Ma 至 1Ma 七谷至鱼沼组地层学。
DOI：
10.3720/japt.64.80
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
K. Kurokawa
中科院分区：
文献类型：
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作者：
K. Kurokawa
利用水下tephra标记层综合研究了日本海一侧新泻地区13Ma-1Ma的Nanatani组与Uonuma组的对比。研究区域包括佐藤岛、西山中央油田、Niitsu-Shitada Hills、Higashiyama-Uonuma Hills、八国油田、Yoneyama地区、Higashikubuki Hill地区、Arai地区和Nishikubiki地区。沉积盆地的地层调查是有效的，特别是在沉积盆地中，从新潟盆地一样，普遍存在着明显的同生异位相关系，从河流-湖泊环境到深海环境。根据广布灰层与Himi群、Tokai群和Kazusa群灰层的对比，以及磁地层学、硅藻和纳米化石带的资料，对主要灰层的年龄进行了估计。2.4 ~ 2.2 ma时，在东久壁南部和Uonuma丘陵地区初步出现了浅海-河流三角洲环境（Uonuma组），2.2 ~ 1.0 ma时，浅海相逐渐向西山中央油田延伸。
Correlation of the Nanatani to Uonuma Formations of 13Ma-1Ma in the Niigata region on the Sea of Japan side was comprehensively investigated using subaqueous tephra marker layers. The examined areas are the Sado Island, Nishiyama-Chuo Oil Field, Niitsu-Shitada Hills, Higashiyama-Uonuma Hills, Hachikoku Oil Field, Yoneyama region, Higashikubuki Hill, Arai region and Nishikubiki region. The tephrostratigraphical investigation was proved to be effective especially in the sedimentary basin prevailing marked contemporaneous heterotopic facies relations from fluvio-lacustrine to bathyal environments as in the Niigata basin. The age estimation of the predominant ash layers was also attempted based on the correlation of widespread ash layers to those in the Himi, Tokai and Kazusa Groups, and on the data of the magnetostratigraphy and diatom and nannofossil zones. The shallow marine to fluvio-deltaic environments (the Uonuma Group) were appeared initially in the southern Higashikubiki and the Uonuma Hills in 2.4-2.2Ma, and the shallow facies progressively extended toward the Nishiyama-Chuo Oil Field in 2.2-1.0Ma.