Transition of clepositional sequences and fossil facies in the Crefaceous Yezo Supergroup

白垩纪叶佐超群中的沉积层序和化石相的转变

• 批准号: 07640619
• 负责人: ANDO Hisao
• 金额: $ 1.47万
• 依托单位: IBARAKI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640619/
• 关键词: Cretaceous; Yezo Supergroup; depositronal sequence; sequence stratrgraphy; fossil facies; shallow-marine deposits; Bivalues; Hokkaido; シーケンス層序学(sequence stratigraphy); 白亜糸; 堆積相; 堆積地質学; 軟体動物化石; 古生態

The uppermost Albian to upper Turonian Mikasa Formation and the Lower Campanian to Lower Maastrichtian Hakobuchi Group, both of which represent the shallow-marine depositional facies of the Yezo Supergroup in the meridional zone of Hokkaido, were investigated from viewpoint of sequence stratigraphy and molluscan biofacies transition. The Mikasa Formation is thought to be composed of three third-order depositional sequences (DS) formed by relative sea-level cycles. Although the lateral and vertical distribution of DSs and constituting systems tract are depending on horizons and geographic position, the basin center seems to have shifted from north to south. Shallow-marine shell beds tend to be contained in the lower shoreface to inner shelf facies of highstand systems tracts.The Hakobuchi Group conspicuously consists of two third-order DSs in the Ashibetsu area, but more than seven DSs of somewhat smaller size in the southern Oyubari to Hobetsu areas. Therefore, relative sea-level chang … More es might have been locally different more or less among areas within the Yezo basin. Since the group in the Nakatonbetsu area of northern Hokkaido is dominated by very thick offshore mudstone facies, the comparison with the Ashibetsu to Hobetsu areas is difficult. But two or three DSs are presumed to exist there. The uppermost one may be Paleocene in age, judging from foraminiferal micropaleontology and paleomagnetic data.Sequence stratigraphic schemes synthesized in this study are compared with other Upper Cretaceous strata in Northeast Japan. The general distribution patterns of DSs for those strata are well synchronous with the Haq curve (global sea-level curves), suggesting an influence of global eustacy, though not all, in addition to local tectonic movement.Shallow-marine molluscan faunal changes of the Mikasa Formation at the Cenomanian-Turonian boundary suggest a remarkable extinction and drastic change of elements in benthic ecosystems. Though fossil beds are scarce in the Hakobuchi Group, such a remarkable change can not be observed during Campanian to early Maastrichtian at least. Less

从层序地层学和软体动物生物相转换的角度研究了代表北海道子午带YEZO超群浅海沉积相的阿尔比安-上都罗统Mikasa组和下坎帕尼亚-下Maastrhtian Hakobuchi群。Mikasa组被认为是由相对海平面旋回形成的三个三级沉积层序(DS)组成。尽管DSS和构成体系域的横向和垂向分布取决于层位和地理位置，但盆地中心似乎已由北向南移动。浅海壳层一般分布在高位体系域的下滨-内陆棚相中，Ashibetsu地区有2个三级DSS，而Oyubari-Hobetsu南部有7个以上规模较小的DSS。因此，相对海平面变化…更多的Es可能在耶佐盆地内的不同地区之间存在或多或少的局部差异。由于北海道北部Nakatonbetsu地区的该群以非常厚的近海泥岩相为主，因此很难与Ashibetsu至Hobetsu地区进行对比。但据推测，那里有两到三个DSS。根据有孔虫微体古生物和古地磁资料判断，最晚的时代可能是古新世。本文综合的层序地层方案与日本东北部其他上白垩统地层进行了对比。这些地层DSS的总体分布模式与HAQ曲线(全球海平面曲线)具有很好的同步性，表明除局部构造运动外，还受到全球隆升的影响。Cenomania-Turung边界Mikasa组的浅海软体动物动物群变化表明，底栖生态系统中的元素发生了显著的灭绝和剧烈变化。尽管客口群化石层位稀少，但至少在寒武纪至马斯特里赫期早期还没有观察到如此显著的变化。较少

项目成果

Ando, H., Seishi, M., Oshima, M.and Matsumaru, T.: "Fluvial-shallow marine depositronal systems of the Futaba Group (Upper Getaceous) -dopositional facies and sequences" Journal of Geography. vol.104. 284-303 (1995)

Ando, H.、Seishi, M.、Oshima, M. 和 Matsumaru, T.：“Futaba 群（上 Getaceous）的河流-浅海沉积系统 - 沉积相和序列”《地理学杂志》。

安藤寿男: "上部白亜系双葉層群の河川成-浅海域堆積システム-堆積相と堆積シーケンス" 地学雑誌. 104. 284-303 (1995)

安藤敏夫：“河流地层-浅海沉积体系-上白垩统双叶群沉积相与沉积序列”地质杂志104。284-303（1995）。

安藤 寿男 ほか3名: "上部白亜系双葉層群の河川成〜浅海成堆積システム-堆積相と堆積シーケンス" 地学雑誌. 104. 284-303 (1995)

Toshio Ando等3人：“上白垩统双叶群的河流到浅海沉积体系——沉积相和沉积序列”地质杂志104。284-303（1995）。

小松 俊文・安藤 寿男: "静岡県西部下部白亜系伊平層の層序と堆積環境" 地学雑誌. 105. 67-76 (1996)

Toshifumi Komatsu 和 Hisao Ando：“静冈县西部下白垩统 Ihei 组的地层学和沉积环境”地质杂志 105. 67-76 (1996)。

Hisao, Ando: "Apparent stacking palters of depositional sequences in the Opper Creta-ceous shallow-marine to flavial successions,Northeast Japan" Memoirs of the Geological Society of Japan. 48. 43-59 (1997)

Hisao, Ando：“日本东北部 Opper Cretaceous 浅海层序到 Flaflaial 序列中沉积层序的明显堆积”，日本地质学会回忆录。