The sedimentological evolution and petroleum potential of a very thick Upper Cretaceous marine mudstone succession from the southern high latitudes—a case study from the Bight Basin, Australia
AuthorWainman, Carmine C.
Jones, Matthew M.
Charles, Adam J.
White, Lloyd T.
Bogus, Kara A.
O'Connor, Lauren K.
McCabe, Peter J.
Holford, Simon P.
AffiliationUniv Arizona, Dept Geosci
MetadataShow full item record
PublisherELSEVIER SCI LTD
CitationWainman, C. C., Tagliaro, G., Jones, M. M., Charles, A. J., Hall, T., White, L. T., ... & Holford, S. P. (2020). The sedimentological evolution and petroleum potential of a very thick Upper Cretaceous marine mudstone succession from the southern high latitudes—a case study from the Bight Basin, Australia. Marine and Petroleum Geology, 104441. https://doi.org/10.1016/j.marpetgeo.2020.104441
JournalMARINE AND PETROLEUM GEOLOGY
Rights© 2020 Elsevier Ltd. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractDuring IODP Expedition 369, a 690 m thick succession of silty claystone spanning the early Turonian to the late Santonian was encountered at Site U1512 in the Bight Basin, offshore southern Australia. Stacking patterns, sedimentary facies and palynological assemblages reveal that the succession was rapidly deposited with hyperpycnal and hypopycnal flows in a marine prodelta setting, which was subject to basin restriction. The dominance of clay-rich facies and phytoclasts in the succession was likely the result of a major river system delivering a high sediment load into the Bight Basin when a warm, wet climate prevailed. A combination of high sedimentation rates (19-272 m/Myr) and accelerated subsidence prevented the delta from rapidly prograding into more distal regions of the basin. The complete Turonian to Santonian mudstone succession yields low total organic carbon (similar to 1 wt%) and Type IV kerogens. However, palynofacies assemblages become progressively marine in character and total organic carbon values vary between 1 and 1.5 wt% with depth. This may indicate that the base of the hole at Site U1512 was close to potential organic-rich black shales associated with Ocean Anoxic Event 2. Low amplitude and irregular reflections on seismic data and disparities between biostratigraphic zonations suggest the upper 350 m of the Turonian to Santonian succession may represent a mass movement that happened during the Pleistocene. This study reveals that Site U1512 material likely represents a near-stratigraphically complete marine mudstone succession from high paleolatitudes, as well as the only depositional record that was fully cored from the Bight Basin.
Note24 month embargo; published online: 11 May 2020
VersionFinal accepted manuscript