Exploratory field work in the Lower and Middle Triassic of Svalbard — Diversity and Stratigraphy of Lower and Middle Triassic Ichthyosauria of Svalbard

我们计划利用我们在美国内华达州奥古斯塔山脉下、中三叠统进行野外工作的丰富经验，勘探铰接式鱼龙材料。以前在斯瓦尔巴特群岛采集的大部分三叠纪鱼龙是由孤立的发现组成的，这些发现是从沉积层中风化的，然后从表面收集的。然而，根据偶然发现的几个更完整的标本，有明确的证据表明岩石中存在关节骨骼。我们相信，沿着化石层位更陡峭的斜坡进行勘探--就像我们在内华达州所做的那样--将导致在斯瓦尔巴特群岛也发现有关节的鱼龙。如果我们的方法成功，我们计划申请更多的实地工作资金，并将这个项目发展成一个完整的研究议程。通过这些新的发现，我们想要检验这样一种假设，即体长超过5米的大型鱼龙已经存在于下三叠世。中三叠世的资料将用于与北半球其他这个时代的动物群进行比较。特别是，应该检验是否存在像奥古斯塔山脉发现的鱼龙分类群的系统发育关系所表明的世界性辐射。

We plan to prospect for articulated ichthyosaur material making use of our extensive experience in conducting field work in the Lower and Middle Triassic in the Augusta Mountains of Nevada, USA. The bulk of Triassic ichthyosaurs previously collected in Svalbard consists of isolated finds that had weathered from the sediment layers and were then collected from the surface. However, based on a few more complete specimens found by chance, there is clear evidence for articulated skeletons in the rock. We are convinced that prospecting along the steeper slopes of the fossiliferous horizons — as we do in Nevada — will result in the discovery of articulated ichthyosaurs also in Svalbard. If our approach is successful, we plan to apply for further fieldwork funds and develop this project into a full research agenda. With the new finds, we want to test the hypothesis that large ichthyosaurs with a body length over 5 m had existed already in the Lower Triassic. The Middle Triassic material shall serve for comparison with other faunas of this age from the northern hemisphere. Especially, it should be tested if there was a worldwide radiation of cymbospondylid ichthyosaur taxa, as suggested by the phylogenetic relationships of the finds in the Augusta Mountains.