Key Boundary Horizons
120 Ma Range
Scrub Geochronology
251.9 Ma
180 Ma (Jurassic)
300 Ma (Carbonif.)
Biostratigraphic Biozone
Daptocephalus / Lystrosaurus Transition
Dicynodont mass turnover, rapid disappearance of herbivorous gorgonopsians, bloom of burrowing survivors.
Observed Telemetry & Proxies
Multiphase Active
δ¹³C Excursion
-4.20 ‰ VPDB
Extinction Rate
78.4 %
Sediment Accum. Rate
42.5 m/Myr
Paleo-Temp / Rain
28.5 °C / 480mm
Microfacies & Lithofacies
Fluvial Overbank
Fluvial sandstone sheets & red mudstones with calcrete nodules, reflecting high-energy braided channel belts punctuated by extreme seasonal drying, sheetfloods, and soil carbonate precipitation.
Multiphase Oscillation Insight:
High-precision CA-TIMS U-Pb zircon geochronology reveals that Gondwana experienced 4 distinct rapid hyperthermal pulses and severe megamonsoon disruptions, refuting the simplistic linear drying model and aligning terrestrial die-offs with Siberian Traps pulses.