Sedimentary depositional environment

Geology

Radiometric dating

Global Boundary Stratotype Section and Point

Cretaceous

Biozone

Political science

Chronostratigraphy

Mathematics

Biology

Cyclostratigraphy

Total organic carbon

Paleontology

Chemostratigraphy

Isotopes of carbon

Sedimentary rock

Biostratigraphy

Excursion

Conodont

Ammonite

Plateau (mathematics)

Mathematical analysis

Ecology

Trilobite

Structural basin

Ordovician

Gondwana Research

Cyclostratigraphic analyses of Upper Pliensbachian and Lower Toarcian carbon-13 isotope (δ13C) data, together with radiometric dating, are used to calibrate biozones and magnetic chrons in the Astronomical Time Scale (ATS). In turn, the ATS is used to date sea-level and climate cycles in relation to the Early Toarcian carbon-isotope excursion (T-CIE) and the Karoo-Ferrar Large Igneous Provinces. The resulting chronology however is insufficiently accurate to determine if these global-scale events are causally related. In particular, cyclostratigraphic analyses typically underestimate the durations of biozones by failing to account for hiatuses in depositional discontinuities. To account for hiatuses this paper constructs a δ13C reference curve consisting of correlative segments from several localities and dates them with ammonite zones and subzones. By comparing the reference curve to those from numerous localities, four major discontinuity-prone intervals were identified and named 'stratigraphic black holes' ...

Calibrating the Early Toarcian (Early Jurassic) with stratigraphic black holes (SBH)