Provenance and diagenesis of Middle Jurassic to Lower Cretaceous clastic sedimentary systems in the SW Scotian Basin and the Fundy Basin

Abstract

Mid Jurassic to Lower Cretaceous clastic deposits in the SW Scotian Basin are poorly known and understood. Detrital mineral chemistry was used to determine their provenance, whereas chemical composition of diagenetic minerals together with textures were used to determine paragenetic sequences. Mid Jurassic sediments indicate a Meguma terrane source, with local rivers and an influence from Labrador, with a river running along the Cobequid-Chedabucto fault zone depositing in the Fundy Basin. Late Jurassic sediments were sourced from the Meguma terrane. Lower Cretaceous sediments have similar sources as Mid Jurassic sediments, except that the Labrador river deposited in the central Scotian Basin. Diagenetic conditions in the SW Scotian Basin are slightly different from those in the Sable sub-basin. Coated grains formed in the sulfidic and ferruginous diagenetic zones. Eodiagenetic minerals imply fully marine conditions, as suggested by the high ratio of Ca[superscript 2+] and Mg[superscript 2+] to Fe[superscript 2+]. Carbonates are the Ca[superscript 2+] source for mesodiagenetic calcite.