The organic-rich shales of the Middle Triassic Botneheia Formation in Svalbard and its correlative units offshore are considered important source rock intervals for oil and gas generation in the Norwegian Barents Shelf region. Detailed investigation of these intervals is essential to better understand the intra source rock variations and thus to improve exploration models. As source rocks are rarely cored during exploration campaigns, outcrop studies of analogue source rocks onshore Svalbard are of great importance for gaining a comprehensive understanding of the Triassic petroleum system offshore. This integrated sedimentological and geochemical study of the Botneheia Formation investigates the intricate relationship between mudstone facies, total sulfur, total organic/inorganic carbon, and the absolute and relative abundance of bulk bitumen content. Both the Muen Member (Anisian) and the overlying Blanknuten Member (mostly Ladinian) of the Botneheia Formation were densely sampled and analyzed from three outcrop localities on Edgeøya, eastern Svalbard. The results show that total sulfur, total organic carbon, bitumen richness, and relative and absolute aromatic hydrocarbon content increase from bioturbated, gray-colored shales in the lower to middle Muen Member upwards into non-bioturbated, phosphogenic black shales in the middle part of the Blanknuten Member. From here, organic carbon and bulk bitumen richness subsequently decrease upwards in concert with the occurrence of bioturbated, calcareous mudstones and impure limestones towards the top of the Blanknuten Member. Optical vitrinite reflectance variations do not suggest significant maturity variations with depth in the sample profiles, highlighting that the total organic carbon and bulk bitumen content are dominantly coupled with the developing source facies. These facies and chemostratigraphic trends mirror the implied marine vs. terrigenous organic matter sedimentation and benthic preservation potential, which were at a maximum in the middle Blanknuten Member. These processes appear to be closely related to the supply of nutritious upwelled waters that are further linked with an evolving pan-Arctic 2nd order Middle Triassic transgressive–regressive sequence. Facies and multivariate analyses of the geochemical data show that the lower to middle Muen Member are comparable to the pro-delta mudstones of the younger Tschermakfjellet Formation (Carnian), and that both units are clearly distinct from the increased source rock potential and richness in the upper part of the Muen Member and the entire Blanknuten Member. This provides evidence of genetically different paleo-depositional environments and source rock properties that are confined to the lower and upper parts of the Middle Triassic Botneheia Formation, and may have wide applications for Triassic source rock assessment in the offshore Norwegian Barents Sea.

斯瓦尔巴群岛中三叠统 Botneheia 组的富有机质页岩及其近海相关单元被认为是挪威巴伦支陆架地区油气生成的重要烃源岩层段。对这些层段的详细调查对于更好地了解烃源岩内的变化并从而改进勘探模型至关重要。由于烃源岩在勘探活动中很少取芯，斯瓦尔巴群岛陆上类似烃源岩的露头研究对于全面了解海上三叠纪石油系统具有重要意义。Botneheia 组的这项综合沉积学和地球化学研究调查了泥岩相、总硫、总有机/无机碳、以及大量沥青含量的绝对和相对丰度。Botneheia 组的 Muen 段（Anisian）和上覆的 Blanknuten 段（主要是 Ladinian）都从斯瓦尔巴群岛东部 Edgeøya 的三个露头地点进行了密集采样和分析。结果表明，从穆恩段中下部的生物扰动的灰色页岩向上到中部的非生物扰动的磷生黑色页岩，总硫、总有机碳、沥青丰富度以及相对和绝对芳烃含量增加。 Blanknuten 成员。从这里开始，随着生物扰动的钙质泥岩和不纯石灰岩的出现，有机碳和大量沥青的丰度随后向上降低，朝向 Blanknuten 段的顶部。光学镜质反射率变化并不表明样品剖面中成熟度随深度的显着变化，突出表明总有机碳和大量沥青含量主要与发育的源相耦合。这些相和化学地层趋势反映了隐含的海相与陆源有机质沉积和底栖保存潜力，它们在布兰克努滕中间段达到最大值。这些过程似乎与有营养的上涌水的供应密切相关，而上涌水又与不断演变的泛北极二阶中三叠世海侵-海退序列进一步相关。地球化学数据的相和多变量分析表明，Muen 中下段与较年轻的 Tschermakfjellet 组（Carnian）的前三角洲泥岩相当，并且这两个单元明显不同于 Muen 段上部和整个 Blanknuten 段增加的烃源岩潜力和丰富度。这提供了成因不同的古沉积环境和烃源岩性质的证据，这些证据仅限于中三叠统 Botneheia 组的下部和上部，并可能在挪威巴伦支海近海的三叠系烃源岩评估中具有广泛的应用。