Marine shelf to paralic biofacies of Upper Triassic to Lower Jurassic deposits in Spitsbergen

► Microfossil facies reflects transgressive-regressive developments. ► Offshore shelf is typified by high diversity calcareous foraminiferal faunas. ► Delta progradation leads to reduced diversity and dominance of agglutinated taxa. ► Boron concentration decreases with decreasing salinity. ► Biofacies augments sequence stratigraphic architecture.