TY - JOUR
T1 - Maturity matters in provenance analysis: Mineralogical differences explained by sediment transport from Fennoscandian and Variscan sources
AU - Olivarius, Mette
AU - Vosgerau, Henrik
AU - Nielsen, Lars Henrik
AU - Weibel, Rikke
AU - Malkki, Sebastian N.
AU - Heredia, Benjamin D.
AU - Thomsen, Tonny B.
N1 - Publisher Copyright:
© 2022 by the authors.
PY - 2022/8/18
Y1 - 2022/8/18
N2 - The significance of mineralogical maturity as a provenance indicator has long been debated and we use this study to demonstrate that it can indeed be a powerful tool to track the distribution of sandstone reservoirs. We investigate the cause of the pronounced geographic and stratigraphic differences in mineralogical composition that are found in the Upper Triassic–Lower Jurassic Gassum Formation across the Norwegian–Danish Basin and surrounding areas. Zircon U-Pb dating of 46 sandstone samples including analysis of 4816 detrital grains are combined with quantifications of the detrital mineralogical composition and placed in a sequence stratigraphic framework. The results show that the Gassum Formation can be divided into a southeastern region with high mineralogical maturity and a less mature region to the northwest with more feldspars, rock fragments, micas, and heavy minerals. Both the mineralogical assemblage and the provenance signature have been thoroughly homogenized in the SE region where sediment supplies from the Fennoscandian Shield and the Variscan Orogen are evident. In the NW region, sediment was initially supplied from Fennoscandia only, but the provenance abruptly changed from the Telemarkia Terrane to comprising also the more distant Caledonian Orogen resulting in a different mineralogical assemblage. The change occurred during a basinwide regression and may be caused by tectonic movements in the hinterland that permanently changed the composition of the sediment supplied to the basin.
AB - The significance of mineralogical maturity as a provenance indicator has long been debated and we use this study to demonstrate that it can indeed be a powerful tool to track the distribution of sandstone reservoirs. We investigate the cause of the pronounced geographic and stratigraphic differences in mineralogical composition that are found in the Upper Triassic–Lower Jurassic Gassum Formation across the Norwegian–Danish Basin and surrounding areas. Zircon U-Pb dating of 46 sandstone samples including analysis of 4816 detrital grains are combined with quantifications of the detrital mineralogical composition and placed in a sequence stratigraphic framework. The results show that the Gassum Formation can be divided into a southeastern region with high mineralogical maturity and a less mature region to the northwest with more feldspars, rock fragments, micas, and heavy minerals. Both the mineralogical assemblage and the provenance signature have been thoroughly homogenized in the SE region where sediment supplies from the Fennoscandian Shield and the Variscan Orogen are evident. In the NW region, sediment was initially supplied from Fennoscandia only, but the provenance abruptly changed from the Telemarkia Terrane to comprising also the more distant Caledonian Orogen resulting in a different mineralogical assemblage. The change occurred during a basinwide regression and may be caused by tectonic movements in the hinterland that permanently changed the composition of the sediment supplied to the basin.
KW - Fennoscandian Shield
KW - Gassum Formation
KW - mineral assemblages
KW - sediment source areas
KW - Variscan Orogen
KW - zircon U-Pb dating
UR - http://www.scopus.com/inward/record.url?scp=85137480127&partnerID=8YFLogxK
U2 - 10.3390/geosciences12080308
DO - 10.3390/geosciences12080308
M3 - Article
AN - SCOPUS:85137480127
SN - 2076-3263
VL - 12
JO - Geosciences (Switzerland)
JF - Geosciences (Switzerland)
IS - 8
M1 - 308
ER -