Foraminiferal Biostratigraphy of the Visean–Serpukhovian (Mississippian) Boundary Interval At Slope and Platform Sections In Southern Guizhou (South China)
Foraminiferal Biostratigraphy of the Visean–Serpukhovian (Mississippian) Boundary Interval At Slope and Platform Sections In Southern Guizhou (South China)
复制标题
DOI：
10.1666/11-111.1
复制
发表时间：
2012-09
期刊：
影响因子：
--
通讯作者：
J. Groves;W. Yue;Qi Yuping;B. Richards;K. Ueno;W. Xiang-dong
中科院分区：
文献类型：
--
作者：
J. Groves;W. Yue;Qi Yuping;B. Richards;K. Ueno;W. Xiang-dong
Visean-Serpukhove界线尚未由全球层型剖面和点(GSSP)确定，但通过在L.nodosa-L.ziegleri计时斜中出现的Lochriea ziegleri牙形刺在操作上是可以识别的。在俄罗斯其他地方和美国中部的Serpukhove阶段的模式区(莫斯科盆地，俄罗斯)，跨越这一边界的有孔虫序列表明，Astero考古Disus postrugosus，Janischewsina delicata，Eolasiodisus donbasicus的出现，以及被争议地称为“Millerella Tortula”的标本，是Serpukhovian基础的可靠的辅助指标。在贵州南部的中国、维辛-瑟普霍夫岩系中，斜坡环境和台地环境分别产生了丰富的牙形石和有孔虫组合。那水剖面是Serpukhoian GSSP的主要候选者，因为它的斜坡沉积包含了包括L.nodosa-L.ziegleri转变在内的牙形刺产状的连续记录。从那水剖面中发现的有孔虫比较罕见，不包括任何基本的Serpukhove指数。相比之下，附近的崖水段代表了一个地台内部环境，在那里有孔虫繁盛，几乎没有牙形刺。雅水Serpukhoian的底部大致以“扭转体”标本的出现为标志。虽然纳水和雅水剖面之间的生物地层对比是不可能的，但雅水剖面上出现的“类似扭转体”的标本可以在与L.ziegleri出现的水平上与莫斯科盆地的Venevian中期亚期进行对比。斜坡和台地剖面共同构成了贵州南部维辛-瑟普霍夫界线微古生物学特征的生物地层学参考区。
Abstract The Visean–Serpukhovian boundary is not yet defined by a Global Stratotype Section and Point (GSSP) but it is recognizable operationally by the appearance of the conodont Lochriea ziegleri in the L. nodosa–L. ziegleri chronocline. Foraminiferal successions across this boundary in the type area of the Serpukhovian Stage (Moscow Basin, Russia), elsewhere in Russia and in the central United States suggest that the appearances of Asteroarchaediscus postrugosus, Janischewskina delicata, Eolasiodiscus donbassicus, and specimens controversially referred to “Millerella tortula” are reliable, auxiliary indices to the base of the Serpukhovian. In southern Guizhou Province, China, Visean–Serpukhovian rock sequences from slope and platform settings have yielded rich associations of conodonts and foraminifers, respectively. The Nashui section is a leading candidate for the Serpukhovian GSSP because its slope deposits contain an uninterrupted record of conodont occurrences including the L. nodosa–L. ziegleri transition. Foraminifers recovered from the Nashui section are comparatively rare and include none of the basal Serpukhovian indices. In contrast, the nearby Yashui section represents a platform interior setting in which foraminifers flourished and conodonts were nearly absent. The base of the Serpukhovian at Yashui is marked approximately by the appearance of “tortula-like” specimens. Although it is not possible to correlate biostratigraphically between the Nashui and Yashui sections, the occurrence of “tortula-like” specimens at the Yashui section allows correlation with the mid-Venevian Substage of the Moscow Basin at a level coinciding with the appearance of L. ziegleri. Together, the slope and platform sections comprise an informative biostratigraphic reference area for micropaleontologic characterization of the Visean–Serpukhovian boundary in southern Guizhou.