Temperature controlled deposition of early Cretaceous (Barremian–early Aptian) black shales in an epicontinental sea
Temperature controlled deposition of early Cretaceous (Barremian–early Aptian) black shales in an epicontinental sea
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陆表海中早白垩世（Barremianâearly Aptian）黑色页岩的温度控制沉积
DOI：
10.1016/j.palaeo.2008.04.026
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Steuber
中科院分区：
文献类型：
--
作者：
Mutterlose;Steuber
对最近在北方德国出露的一个连续的、103 m厚的Barremian-early Aptian年龄的泥岩序列进行了记录，并对其大型动物群含量和地球化学（δ 13 C、δ 18 O）进行了分析。根据常见的箭石和罕见的菊石的发现，详细的生物带已建立覆盖完整的Barremian-early Aptian间隔，包括中早期Aptian“Fischerifer”，其沉积发生在海洋Anoenopsis事件1a。在整个层序中非常常见的是具有高达7%的高TOC含量的精细层状黑色页岩（Blätterton）。这些层状黑色页岩中CaCO 3含量高达60%，与暗色和碳酸盐贫乏的粘土互层，其规模从分米到数米不等。底层沃茨的氧耗尽是指层状层段，因为这些层段没有任何底栖生物化石。在较潮湿的时期，由附近内陆更强烈的径流造成了水柱的盐度驱动分层。这和增加地表水生产力被视为一个可能的原因与观察主要是基于微古生物学证据（甲藻，calcispheres，钙质超微化石）的层压。对箭石的稳定同位素（δ 13 C、δ 18 O）研究表明，巴列姆阶的δ 13 C值为0‰ ~ 2‰。在Aptian早期Fischerchefer正上方约4‰的显著正偏移与海洋缺氧事件1a后Aptian早期中期的全球正δ 13 C偏移很好地相关。因此，这是第一次记录到北半球的δ 13 C正偏移，证实了信号的全球性质。巴雷姆晚期-阿普第阶早期δ 18 O值约2‰的偏移被解释为温度降低了约8°C。这种冷却沿着从巴列姆纪早期厚（高达6.5米）的Hauptblätterton到巴列姆纪晚期薄（10厘米到20厘米）的纹层岩（Blätterton）的转变。在豪普布拉特顿的沉积过程中，非常温暖的条件导致了长期（> 500 kyrs）稳定的水分层。巴列姆纪晚期较冷的温度降低了水分层的稳定性，导致薄层状岩和深色粘土的短期交替。这些观察结果表明，在早期Barremian Hauptblätterton缺氧条件的温度控制的高峰，随后在晚期Barremian和早期Aptian从缺氧到亚氧条件的短期变化。
A continuous, 103m thick mudstone sequence of Barremian–early Aptian age, recently exposed in northern Germany, has been logged and analyzed with respect to its macrofaunal content and its geochemistry (δ13C, δ18O). Based on common belemnite and rarer ammonite findings a detailed biozonation has been established covering the complete Barremian–early Aptian interval, including the mid early Aptian “Fischschiefer”, the deposition of which occurred during Oceanic Anoxic Event 1a. Quite common throughout the sequence are finely laminated black shales (Blätterton) with high TOC contents of up to 7%. These laminated black shales with CaCO3contents of up to 60% are interbedded with dark and carbonate-poor clays on the scale of decimeters to several meters. Oxygen depletion of bottom waters is indicated for the laminated intervals since these are barren of any benthic fossils. A salinity driven stratification of the water column during more humid periods was caused by a more intense run-off from the nearby hinterland. This and increased surface water productivity are seen as a possible cause for the lamination with observations being mainly based on micropalaeontological evidence (dinoflagellates, calcispheres, calcareous nannofossils). Stable isotope studies (δ13C, δ18O) performed on belemnite guards show δ13C values of 0‰ to 2‰ for the Barremian. A distinctive positive excursion of ~ 4‰ directly above the early Aptian Fischschiefer correlates well with the global positive δ13C excursion of mid early Aptian age following the Oceanic Anoxic Event 1a. This first record of the δ13C positive excursion from the Boreal Realm therefore confirms the global nature of the signal. A shift in δ18O values of about 2‰ in the late Barremian–early Aptian is interpreted as a temperature decrease by ~ 8°C. This cooling goes along with a shift from the thick (up to 6.5m) early Barremian Hauptblätterton to thin (10cm to 20cm) laminites (Blätterton) in the late Barremian. During the deposition of the Hauptblätterton very warm conditions caused a long lasting (> 500kyrs) stable water stratification. The cooler temperatures of the late Barremian reduced the stability of the water stratification resulting in rather short termed alternations of thin laminites and dark clays. These observations suggest a temperature controlled peak of anoxic conditions in the early Barremian Hauptblätterton and subsequently short termed changes from anoxic to suboxic conditions in the late Barremian and early Aptian.
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北海地区侏罗纪-早白垩世最新事件与晚西梅里不整合面
影响因子：
3.5
作者：
P. Rawson;L. A. Riley
通讯作者：
L. A. Riley
北方早白垩世钙质超微化石的季节变化
DOI：
--
发表时间：
1989
期刊：
影响因子：
--
作者：
E. Thomsen
通讯作者：
E. Thomsen
影响因子：
2.1
作者：
J. Mutterlose
通讯作者：
J. Mutterlose
黑尔戈兰 Fischreste aus dem Töck (Unter-Aptien)
DOI：
--
发表时间：
1973
期刊：
影响因子：
--
作者：
Louis Paul Taverne;Peter
通讯作者：
Peter
Karbonat-Bombe，一种用于测定沉积物、土壤和其他材料中碳酸盐含量的简单装置
DOI：
--
发表时间：
1971
期刊：
影响因子：
--
作者：
M. German;Gastner Manfred
通讯作者：
Gastner Manfred