Late Cretaceous to early Paleocene climate and sea-level fluctuations: the Tunisian record
Late Cretaceous to early Paleocene climate and sea-level fluctuations: the Tunisian record
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DOI：
10.1016/s0031-0182(01)00395-9
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发表时间：
2002-02-28
影响因子：
3
通讯作者：
Stinnesbeck, W
中科院分区：
文献类型：
--
作者：
Adatte, T;Keller, G;Stinnesbeck, W
气候和海平面的波动在突尼斯的K-T过渡期的基础上散装岩石和粘土矿物，生物地层学和岩性在五个部分（El Melah，El Kef，Elles，Ain Settara和Seldja）从开阔的海洋到浅内浅海环境。在El Kef和Elles研究的Campanian晚期到Danian早期的趋势表明，气候越来越潮湿，与海平面波动和增加的碎屑流入有关，在K-T转换时达到高潮。特提斯区域湿度和径流增加的长期趋势与中高纬度的冷却有关。K-T转换的短期变化结果表明，在K-T边界以下约25-100 ka的最后Maastrichtian海平面低水位的回归标志着增加的碎屑流入在El Kef和Elles和Ain Settara的短暂中断。马斯特里赫特阶末期海平面的上升表现在Elles和El Kef的有孔虫堆积岩的沉积上。洪泛面和凝聚沉积标志着富含陆源有机质的K-T界线粘土。P0-P1 a过渡的标志是一个海平面低水位对应于一个短的间断在Ain Settara，其中大部分的PO是失踪和一段时间的非沉积和侵蚀的下部P1 a（64.95马）。在Seldja，PO和可能的CF 1的最高部分丢失。这些海平面波动与最大湿度有关。这些数据表明，在突尼斯，长期的环境应力在过去的500万年前的K-T边界和持续到早期Danian主要与气候和海平面波动。在这一长期气候趋势中，最新的马斯特里赫特带CF 1内明显的温暖和潮湿事件可能与德干火山活动引起的温室条件有关。在K-T边界或附近没有任何显着的粘土矿物变化和Ir异常表明，火流星的影响有一个相对偶然的短期影响在特提斯地区的气候。(C)2002爱思唯尔科技有限公司。保留所有权利。
Climate and sea-level fluctuations across the Cretaceous-Tertiary (K-T) transition in Tunisia were examined based on bulk rock and clay mineralogies, biostratigraphy and lithology in five sections (El Melah, El Kef, Elles, Ain Settara and Seldja) spanning from open marine to shallow inner neritic environments. Late Campanian to early Danian trends examined at El Kef and Elles indicate an increasingly more humid climate associated with sea-level fluctuations and increased detrital influx that Culminates at the K-T transition. This long-term trend in increasing humidity and runoff in the Tethys region is associated with middle and high latitude cooling. Results of short-term changes across the K-T transition indicate a sea-level lowstand in the latest Maastrichtian about 25-100 ka below the K-T boundary with the regression marked by increased detrital influx at El Kef and Elles and a short hiatus at Ain Settara. A rising sea-level at the end of the Maastrichtian is expressed at Elles and El Kef by deposition of a foraminiferal packstone. A flooding surface and condensed sedimentation mark the K-T boundary clay which is rich in terrestrial organic matter. The P0-P1a transition is marked by a sea-level lowstand corresponding to a short hiatus at Ain Settara where most of PO is missing and a period of non-deposition and erosion in the lower part of P1a (64.95 Ma). At Seldja, PO and possibly the topmost part of CF1 are missing. These sea-level fluctuations are associated with maximum humidity. These data suggest that in Tunisia, long-term environmental stresses during the last 500 ka before the K-T boundary and continuing into the early Danian are primarily related to climate and sea-level fluctuations. Within this long-term climatic trend the pronounced warm and humid event within the latest Maastrichtian Zone CF1 may be linked to greenhouse conditions induced by Deccan volcanism. The absence of any significant clay mineral variations at or near the K-T boundary and Ir anomaly suggests that the bolide impact had a relatively incidental short-term effect on climate in the Tethys region. (C) 2002 Elsevier Science B.V. All rights reserved.