Abstract Transform margins represent strike-slip type of plate boundaries that form during continental breakup and initial ocean opening. They are often characterized by margin-parallel highs with exposed pre- and syn-rift sequences. The Voring Transform Margin, offshore mid-Norway, initiated in the earliest Eocene during the opening of the NE Atlantic. Here, 2D seismic reflection data reveal a transform margin high, the Mimir High. The western flank of this undrilled structure is a kilometer-high escarpment where seismic reflections of pre-breakup age are truncated at the seafloor. The aim of this study was to recover seabed rock samples from the outcropping or shallowly buried sedimentary sequences to provide a geological tie to the regional seismic framework, thereby constraining the basin history and tectono-stratigraphic development. Seabed samples were successfully collected from 14 gravity core and Selcore stations and 10 ROV (remotely operated vehicle) sites along a 750 m high sampling profile, recovering clay, shales, sandstones and glacial dropstones. Biostratigraphy results revealed that the ages of the sedimentary rocks follow the stratigraphic order predicted by the initial seismic interpretation, with Upper Cretaceous sediments at the base and lower Eocene sediments at the top. The integrated interpretation shows that the Mimir High area, including parts of the outer Voring and More basins and the proto-Jan Mayen Microplate Complex, were characterized by the deposition of late Campanian to early Maastrichtian, near coastal and shale-dominated sequences with poor source rock qualities. The early Paleocene samples indicate deep marine conditions that abruptly ended by rapid uplift of the Mimir High in the earliest Eocene. Finally, a reworked Pliensbachian palynomorph assemblage in potential early Eocene strata indicate the presence of exposed Mesozoic sequences in the vicinity of the Mimir High. We argue that some of the lower Eocene sediments where deposited within a hypothetical drainage system sourced from Greenland (Traill O or Jameson Land) and/or from the Jan Mayen Ridge prior to continental separation, and not the result of recent ice-rafting.

中文翻译：

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上白垩统-古近纪地层与挪威海沃林转换边缘密米尔高地的发育

摘要 转换边缘代表在大陆分裂和初始海洋开放期间形成的走滑型板块边界。它们通常以边缘平行高点为特征，暴露前和同步裂谷序列。位于挪威中部近海的 Voring Transform Margin 起源于最早的始新世，在 NE 大西洋开放期间。在这里，二维地震反射数据揭示了一个高变换边界，即密米尔高。这个未钻结构的西侧是一个千米高的悬崖，在海底截断了破裂前时代的地震反射。本研究的目的是从露头或浅埋沉积层序中提取海底岩石样本，以提供与区域地震框架的地质联系，从而限制盆地历史和构造地层发展。沿着 750 m 高的采样剖面从 14 个重力岩心站和 Selcore 站以及 10 个 ROV（远程操作车辆）站点成功采集了海底样品，回收了粘土、页岩、砂岩和冰川落石。生物地层学结果表明，沉积岩的年龄与最初地震解释预测的地层顺序一致，底部为上白垩统沉积物，顶部为下始新世沉积物。综合解释表明，Mimir High 地区，包括外围Voring and More 盆地的部分地区和原Jan Mayen 微板块杂岩，以晚坎帕阶—早马斯特里赫特沉积为特征，近岸、页岩为主的层序沉积，来源贫乏岩石品质。早期的古新世样本表明，在最早的始新世，由于密米尔高地的快速抬升而突然结束的深海条件。最后，在潜在的早始新世地层中重新设计的 Pliensbachian 孢粉形组合表明在 Mimir High 附近存在暴露的中生代序列。我们认为，在大陆分离之前，一些始新世下层沉积物沉积在源自格陵兰岛（Trail O 或詹姆森地）和/或扬马延海岭的假设排水系统中，而不是最近的冰筏漂流的结果。