Testing the Neoproterozoic Snowball Earth in Svalbard

斯瓦尔巴特群岛的Hecla Hoeck岩系是世界上新元古代晚期碳酸盐岩最完整、出露最好的剖面之一。它包含了两个冰期的沉积物和另外两个冰期的碳13同位素（d13 C）证据。 这种保存很重要，因为有证据表明，后生动物爆发之前的事件是地球历史上最不寻常的事件之一。 先前的研究表明，发生了一系列失控的冰灾，每一次都导致了数百万年来海洋表面生物生产力的实际崩溃。 地层学证据包括一个独特的协会冰川diamicrites，帽碳酸盐，和极端的d13 C摆动。首席研究员将在斯瓦尔巴特群岛的Hecla Hoek继承中检验新元古代“雪球”地球假说。 他将使用在世界范围内新元古代碳酸盐岩中成功使用的综合层序和化学地层工具。 在如此古老的岩石上，很有可能出现无法预料的结构复杂性。 因此，他将通过检验加里东期伸展拆离将纽约弗里斯兰东部的新元古代沉积序列与西部的加里东期变质杂岩分开的假设，来解决“深不见底”的Hecla Hoeck地槽的经典问题。 这关系到东、西geon-18基底的关系。 这种关系是重建超大陆Rodinia北大西洋的关键。 现有的古地理重建Rodinia的这一部分是有争议的，但他们被认为是新元古代古气候模型的边界条件。 氩-氩（4040-3940）稳定同位素分析将用于建立地质年代学。

The Hecla Hoeck succession in Svalbard is one of the most complete and well-exposed late Neoproterozoic sections of carbonate rocks in the world. It contains the deposits of two glacial episodes and carbon-13 isotopic (d13C) evidence for two other glacial episodes. This preservation is important because evidence suggests that events preceding the metazoan explosion were among the most extraordinary in Earth's history. Prior research indicate that a series of runaway ice albedo catastrophes occurred with each one leading to a virtual collapse of biological productivity in the surface ocean for millions of years. Stratigraphic evidence includes a unique association of glacial diamicrites, cap carbonates, and extreme d13C swings. The Principal Investigator will test the Neoproterozoic "snowball" Earth hypothesis in the Hecla Hoek succession in Svalbard. He will use integrated sequence and chemostratigraphic tools successfully used in Neoproterozoic carbonates worldwide. There is a strong possibility of unforeseen structural complications on such old rocks. Therefore, he will address the classical problem of the "bottomless" Hecla Hoeck geosyncline by testing the hypothesis that a Caledonian extensional detachment separates the Neoproterozoic sedimentary succession of eastern Ny Friesland from the Caledonian metamorphic complex to the west. This bears on the relationship between geon-18 basement to the west and geon-18 basement to the east. This relationship is key to the reconstructions of the North Atlantic in the supercontinent Rodinia. Existing paleogeographic reconstructions of this part of Rodinia are controversial, but they are believed to serve as boundary conditions for models of Neoproterozoic paleoclimate. Argon-argon (4040-3940) stable isotope analyses will be used to establish the geochronolgy.