华南寒武纪有机质壁微体化石的新发现和其地层对比意义

There are three major types of Fossil-Lagerst?tten recorded in the Cambrian strata worldwide. They are Burgess Shale-type, ?rsten-type and microscopic Burgess Shale-type deposits, and these deposits of exceptional preservation have been found in South China craton. Guided by the collaborator Nick Butterfield at Cambridge University we have adapted modified paleopalynological methods to macerate samples. Preliminary results yield well-preserved organic-walled microfossils, which belong to the third type of Fossil-Lagerst?tten mentioned above. In addition to many kinds of acritarchs and algae, there are fragments of metazoans, including Wiwaxia sclerites, brachiopod pieces and cuticles of vermiform animals, found in the samples. This taphonomic window can offer an important supplementary view of the delicate structures of some metazoans, which will be helpful to fossil classification and biostratigraphic interpretations. In particular, it broadened the species diversity that can contribute to petroleum source rock in a sedimentary basin. By doing more fieldwork, and trying more methods to improve sample recovery during maceration we aim to find more meaningful microfossils to broaden our knowledge about the biodiversity of Cambrian life. On the other hand, an attempt will be made to carry out acritarch-based Cambrian biostratigraphy of South China, combined with the standard trilobite biostratigraphy and chemostratigraphy.

全球寒武系地层中存有三大类型特异埋藏化石库，即布尔吉斯页岩型、?rsten 型和微体布尔吉斯页岩型化石库，且这三类型化石均在中国华南地区都有发现。申请人曾得到英国剑桥大学合作者Nick Butterfield的指导并采用改良后的古孢粉学处理方法，对从贵州寒武系经典剖面采集的样品进行酸泡处理并获得了许多第三类型的标本。除了已报道过的疑源类和丝状藻类之外，同时还发现了后生动物残片，如威瓦西虫的骨板、腕足动物壳体有机质层残片以及蠕形动物表皮有机质膜等新材料，为研究特殊后生动物的有机质结构和微体生物地层指标方面提供了不可或缺的信息。尤其是对了解烃源岩中有机质的成分能有更广泛的认识。希望通过大量的野外工作、技术改良和大量地酸泡样品，能发现更多有意义的化石证据来阐述寒武纪生命的多样性。此外，尝试性地用疑源类以及后生生物的有机质化石对华南寒武系地层作地层划分，并与三叶虫生物地层和同位素地层交叉对比论证。

有标注的成果包括SCI待刊论文1篇、核心期刊论文1篇、会议论文5篇。资助期间，培养1名硕士研究生毕业，并且获得发明专利1项。本团队负责人获得2012年度中国科学院青年科学家国际合作奖和第二届中国古生物学青年古生物学奖。发表的论文中提出了一个新名词——小碳化石库，打开了揭示研究国内寒武纪生命大爆发的新窗口。同时利用碳同位素SPICE事件获得华南华北板块芙蓉统地层对比新进展。