The Guadalupian (Permian) Kamura event in European Tethys
The Guadalupian (Permian) Kamura event in European Tethys
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DOI：
10.1016/j.palaeo.2010.09.034
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发表时间：
2011-07
期刊：
影响因子：
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通讯作者：
Y. Isozaki;D. Aljinović;H. Kawahata
中科院分区：
文献类型：
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作者：
Y. Isozaki;D. Aljinović;H. Kawahata
为了记录赤道西古特提斯在中二叠世晚期瓜达卢佩大灭绝之前的古环境条件，利用稳定碳同位素对Velebit Mtn.克罗地亚中部。通过对Capitanian（Upper Guadalupian）Velebit组72个碳酸盐岩样品的分析，发现了一个δ 13 C值异常高（+4 ~+6‰）的层段。150 m厚的Yabeina（fusuline）带。这一发现表明，在古特提斯最西部的卡庇塔尼安期，沉积物的初级生产力和埋藏速率相当高。这种化学地层学信号与在日本中泛海桑古环礁灰岩中发现的“Kamura事件”具有很好的相关性。本研究结果首次在欧洲古特提斯地区与中泛海萨古海山相对的地球仪上确认了卡姆拉事件，证明了该事件的全球背景及其在化学地层对比中的实用性。为了在全球范围内提高生物生产力，增加营养供应是不可避免的。除了来自泛大陆的河流径流外，活跃的海洋环流，特别是富含营养物质的深海水的上涌，可能对泛地中海和古特提斯都至关重要。一些瓜达卢佩动物群的灭绝，特别是光共生群落（大型测试的fusulines，大型双壳类，皱纹珊瑚），可能与暂时冷却加上富营养化的低纬度浅海环境的古特提斯和泛地中海。
In order to document paleoenvironmental conditions of the equatorial western Paleo-Tethys during the late Middle Permian prior to the end-Guadalupian mass extinction, chemostratigraphic analysis using stable carbon isotopes was conducted for the Guadalupian rocks at Brusane in the Velebit Mtn., central Croatia. By analyzing 72 carbonate samples of the Capitanian (Upper Guadalupian) Velebit Formation, we found an interval with unusually high δ13Ccarbvalues (+4 to +6‰) in the ca. 150m-thick Yabeina (fusuline) Zone. The present find clarifies that the primary productivity and burial rate into the sediments were considerably high during the Capitanian in westernmost Paleo-Tethys. This chemostratigraphic signal is properly correlated with the “Kamura event” detected in a mid-Panthalassan paleo-atoll limestone in Japan. The present results identify the Capitanian “Kamura event” for the first time in European Paleo-Tethys on the opposite side of the globe from the mid-Panthalassan paleo-seamount, and prove the global context of the event as well as its utility in chemostratigraphic correlation. In order to enhance bioproductivity on a global scale, the increase in nutrient supply is inevitable. In addition to riverine run-off from Pangea, active oceanic circulation, in particular upwelling of deep-sea water enriched in nutrients, was likely vital both in Panthalassa and Paleo-Tethys. The extinction of some Guadalupian fauna, in particular photosymbiotic community (large-tested fusulines, large bivalves, rugose corals), was likely related to a temporary cooling coupled with eutrophication in low-latitude shallow marine environments of Paleo-Tethys and Panthalassa.