Four cores from Vestnesa Ridge on the western Svalbard margin from water depth of 1200 m have been studied. The Vestnesa Ridge is known for the presence of numerous pockmarks and active methane gas seepage is often observed in the form of acoustic gas flares. Three of the cores were collected from a pockmark with active seepage of methane and one core was taken just outside the seepage area for comparison. The cores show a range of influence from methane from no seepage (control core), moderate seepage, strong seepage to very strong seepage. All cores have been analyzed for the distribution of macrofossils, trace fossils, planktic foraminifera, stable isotopes, geochemistry and sedimentology. The main purpose of the study is to improve knowledge about the fossil macrofauna and past methane emissions in the area. The results show a major difference between the fauna recovered from cores taken inside a pockmark with chemosymbiotic bivalves and in some cases with a rich macrofauna and from the core recovered outside the pockmark that contained no macrofauna. The faunal relationships with the sedimentary environments confirm a close connection between the macrofauna and the presence/absence of cold-seepage, particularly seen in the occurrence of chemosymbiotic bivalves Archivesica arctica, Isorropodon nyeggaensis, potentially chemosymbiotic Rhacothyas kolgae and polychaetes. A barren zone in the core that was taken from the deepest part of the pockmark may indicate that a blow-out took place in the late glacial and the deglaciation into the early Holocene at c. 21,000–9000 years.

中文翻译：

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弗拉姆海峡东部 Vestnesa Ridge 岩心中的冷渗大型动物群落

已经研究了斯瓦尔巴群岛西部边缘 Vestnesa Ridge 的四个岩心，水深为 1200 m。Vestnesa Ridge 以存在许多麻点而闻名，并且经常以声学气体耀斑的形式观察到活跃的甲烷气体渗漏。其中三个岩心是从一个甲烷活跃渗出的麻点中收集的，一个岩心刚好在渗漏区域之外进行比较。岩心显示出从无渗流（控制岩心）、中等渗流、强渗流到极强渗流的甲烷影响范围。对所有岩心的大型化石、微量化石、浮游有孔虫、稳定同位素、地球化学和沉积学的分布进行了分析。该研究的主要目的是提高对该地区化石大型动物和过去甲烷排放的了解。结果表明，从具有化学共生双壳类动物和在某些情况下具有丰富大型动物群的麻坑内的岩芯中回收的动物群与从麻坑外回收的不含大型动物群的岩芯中发现的动物群之间存在重大差异。与沉积环境的动物群关系证实了大型动物群与冷渗流的存在/不存在之间的密切联系，特别是在化学共生双壳类 Archivesica arctica、Isorropodon nyeggaensis、潜在的化学共生 Rhacothyas kolgae 和多毛类动物的发生中。从麻点最深处取下的核心贫瘠带可能表明晚冰期发生了井喷，并在 c. 进入全新世早期冰川消融。21,000-9000 年。