Silicified glendonites in the Ediacaran Doushantuo Formation (South China) and their potential paleoclimatic implications
Silicified glendonites in the Ediacaran Doushantuo Formation (South China) and their potential paleoclimatic implications
复制标题
埃迪卡拉系陡山沱组硅化角砾岩及其潜在的古气候意义
作者：
Suess E;Wang G;Chen C;Xiao S
埃迪卡拉纪被纽芬兰约580 Ma的加斯基尔冰川所打断。然而，在中国南部的埃迪卡拉纪序列中，古气候数据很少，丰富的地球化学和古生物数据正在形成对埃迪卡拉纪演化和环境历史的认识。本文报道了中国地块南部陆架内沉积的埃迪卡拉纪陡山沱组中硅化绿泥石的产状。岩石学证据表明，这些硅化绿泥石是在近冰点温度下形成的同沉积或早期自生伊卡岩之后的假象。含绿泥岩地层段具有正的δ~(13)C值。它早于负δ13C漂移en3(被广泛认为相当于舒拉姆负漂移)和漂移en2。尽管可能有不同的解释，但这些花岗岩可能与加斯基尔冰川有关。如果得到证实，这种关联表明舒拉姆事件发生在加斯基尔冰川之后，因此对埃迪卡拉纪的气候变化、碳循环和生物进化具有重要意义。
The Ediacaran Period is punctuated by the ca. 580 Ma Gaskiers glaciation in Newfoundland. However, paleoclimatic data are scarce in Ediacaran successions in South China, where abundant geochemical and paleobiological data are shaping current understanding of Ediacaran evolutionary and environmental history. Here, we report the occurrence of silicified glendonites in the Ediacaran Doushantuo Formation deposited in an inner-shelf environment on the South China block. Petrographic evidence suggests that these silicified glendonites are pseudomorphs after syndepositional or early authigenic ikaites formed at near-freezing temperatures. The glendonite-bearing stratigraphic interval is characterized by positive δ13C values. It predates both the negative δ13C excursion EN3 (widely believed to be an equivalent of the Shuram negative excursion) and excursion EN2. Although alternative interpretations may be possible, these glendonites may be related to and correlated with the Gaskiers glaciation. If confirmed, this correlation suggests that the Shuram event postdates the Gaskiers glaciation, thus having important implications for Ediacaran climate changes, carbon cycles, and biological evolution.
登录
查看更多内容
DOI：
10.1016/j.palaeo.2013.03.001
发表时间：
2013-11
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
B. Teichert;F. Luppold
通讯作者：
B. Teichert;F. Luppold
DOI：
--
发表时间：
2010
期刊：
Acta Geological Sinica
影响因子：
--
作者：
Chen Shou-ming
通讯作者：
Chen Shou-ming
影响因子：
5.8
作者：
C. Calver;L. P. Black;J. Everard;D. B. Seymour
通讯作者：
C. Calver;L. P. Black;J. Everard;D. B. Seymour
影响因子：
1.6
作者：
M. Whiticar;E. Suess
通讯作者：
M. Whiticar;E. Suess
影响因子：
3.7
作者：
Sahoo, S. K.;Planavsky, N. J.;Lyons, T. W.
通讯作者：
Lyons, T. W.