The late Albian-early Cenomanian oceanic anoxic event 1d (OAE-1d; ~ 103 to 99.5 Ma) represents a global interval of enhanced organic carbon burial due to widespread oxygen deficiency in the water column and/or increased primary productivity. The biostratigraphy and geochemistry of organic-rich sediments in the La Grita Member (Capacho Formation) in southwestern Venezuela were studied to document the paleoenvironmental conditions that governed the deposition of this succession during OAE-1d. Carbon-isotope (δ 13 C carb and δ 13 C Corg ) chemostratigraphy and biostratigraphic constraints show that the La Grita Member spans the late Aptian period (Rotalipora appenninica Zone), and that OAE-1d is well recorded in this succession. A prominent increase in total organic carbon (TOC) values (up to 10%) is clearly recorded through the onset of OAE-1d, coinciding with a prominent change in
Two composite sedimentary sequences sampled in the ice‐proximal (12CS) and ice‐distal (02CS) areas of Coronation Fjord (Baffin Island, Nunavut, Canada) were investigated in order to reconstruct the effect of climate variability on 600 years of changes in sediment transfer from the eastern Penny Ice Cap (PIC). Detrital proxies, and physical and sedimentological analyses revealed that glacial meltwater discharges led to frequent rapidly deposited layers (RDLs) in ice‐proximal settings. RDLs in ice‐distal settings involved the sudden release of a large quantity of sediment‐laden water during floods probably originating from adjacent fjords with large sandur deltas. Laminated sediments with ice‐rafted debris throughout the Little Ice Age interval in the ice‐proximal environment suggest that colder conditions promoted glacier growth, leading to successive episodes of turbid hyperpycnal meltwater plumes and iceberg calving in Coronation Fjord. Since 1850 ce, the accelerated Coronation retreat in response to modern warming has led to increased sedimentation rates, abrupt mineralogical and grain size proxy variations and more frequent RDLs. Similar trends between the detrital proxies of the ice‐proximal core and Atlantic Multidecadal Oscillation record and Arctic surface air temperature suggest high connectivity between atmospheric and sea surface temperature variations and PIC dynamics over the last 600 years.
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