TY - JOUR
T1 - Provenance Variability in Coeval Slope Channel Systems
T2 - Hermod S2 Member Sandstone (Eocene), South Viking Graben (North Sea)
AU - Luzinski, Wiktor Marek
AU - Morton, Andrew C.
AU - Hurst, Andrew
AU - Tøllefsen, Ingeborg Ims
AU - Cater, John
N1 - Funding Information: This research was conducted as part of a Ph.D. project funded by AkerBP.
Acknowledgments: We would like to express our deepest gratitude to sponsors from AkerBP who kindly provided funding and data necessary for this research. We would also like to thank Kingba Princewill, Ahmed Jama Ahmed, Elliot Foley and Fraser Scott for their outstanding work on their respective MSc projects, which helped further this research, and other staff at the University of Aberdeen, most notably John Still for his support with microprobe analysis.
This article belongs to the Collection Detrital Minerals: Their Application in Palaeo-Reconstruction)
PY - 2022/12/6
Y1 - 2022/12/6
N2 - Conventional and varietal heavy mineral studies of the earliest Eocene Hermod S2 Member (Mbr) sandstones in the Greater Alvheim area of the northern North Sea have revealed marked lateral variations and more subtle vertical evolution in provenance signature. Major variations are of geographic rather than stratigraphic nature as biostratigraphy reveals that all investigated sandstones are coeval. The provenance variations show an organized pattern, with sandstones in the north showing a different signature than those in the south. The position of the sandstones relative to the East Shetland Platform (ESP) is inferred to be the main control on provenance, with sediment input from at least two different point sources. Sediment supplied from both catchments is predominantly recycled in nature, given the mineralogical maturity of the heavy mineral assemblages, consistent with the evidence for widespread Permo-Triassic and Devonian sediments on the ESP. However, some direct supply from metasedimentary (Moine and Dalradian) basement is implied by the sporadic occurrence of unstable minerals. The southern catchment incorporated a greater exposure of Permo-Triassic sandstones than the northern catchment. The Permo-Triassic part of the catchment can be reconstructed as comprising equivalents of the Foula and Otter Bank sandstones present to the west of Shetland, with the majority of the Foula section having been stripped off prior to Hermod S2 deposition, exposing Otter Bank equivalents for erosion and redeposition. However, remnant Foula-like sandstones remained exposed further south on the ESP until at least the earliest Eocene since Foula-type garnet signatures are found in the Forties Sandstone Mbr of the central North Sea. In addition to lateral differences, stratigraphic evolution of provenance can also be detected in the Hermod S2 Mbr, with variations in key provenance-sensitive parameters related to a sea-level rise that reduced the extent of alluvial storage and altered the geological framework of the hinterland.
AB - Conventional and varietal heavy mineral studies of the earliest Eocene Hermod S2 Member (Mbr) sandstones in the Greater Alvheim area of the northern North Sea have revealed marked lateral variations and more subtle vertical evolution in provenance signature. Major variations are of geographic rather than stratigraphic nature as biostratigraphy reveals that all investigated sandstones are coeval. The provenance variations show an organized pattern, with sandstones in the north showing a different signature than those in the south. The position of the sandstones relative to the East Shetland Platform (ESP) is inferred to be the main control on provenance, with sediment input from at least two different point sources. Sediment supplied from both catchments is predominantly recycled in nature, given the mineralogical maturity of the heavy mineral assemblages, consistent with the evidence for widespread Permo-Triassic and Devonian sediments on the ESP. However, some direct supply from metasedimentary (Moine and Dalradian) basement is implied by the sporadic occurrence of unstable minerals. The southern catchment incorporated a greater exposure of Permo-Triassic sandstones than the northern catchment. The Permo-Triassic part of the catchment can be reconstructed as comprising equivalents of the Foula and Otter Bank sandstones present to the west of Shetland, with the majority of the Foula section having been stripped off prior to Hermod S2 deposition, exposing Otter Bank equivalents for erosion and redeposition. However, remnant Foula-like sandstones remained exposed further south on the ESP until at least the earliest Eocene since Foula-type garnet signatures are found in the Forties Sandstone Mbr of the central North Sea. In addition to lateral differences, stratigraphic evolution of provenance can also be detected in the Hermod S2 Mbr, with variations in key provenance-sensitive parameters related to a sea-level rise that reduced the extent of alluvial storage and altered the geological framework of the hinterland.
KW - Eocene
KW - heavy mineral analysis
KW - Hermod
KW - provenance
KW - stratigraphy
KW - Viking Graben
UR - http://www.scopus.com/inward/record.url?scp=85144686607&partnerID=8YFLogxK
U2 - 10.3390/geosciences12120450
DO - 10.3390/geosciences12120450
M3 - Article
AN - SCOPUS:85144686607
VL - 12
JO - Geosciences
JF - Geosciences
SN - 2076-3263
IS - 12
M1 - 450
ER -