A major sea-level drop briefly precedes the Toarcian oceanic anoxic event: implication for Early Jurassic climate and carbon cycle.

摘要: Sea-level change is an important parameter controlling the expansion of oxygen-depleted conditions in neritic settings during oceanic anoxic events (OAEs). Despite this fundamental role, it remains on a short timescale ( 50 m) and duration forced regression suggests that was most likely related to transient waxing waning polar ice sheet. We suggest short-lived glaciation might have genetic link with inception Toarcian OAE. Indeed, deglaciation accompanying sea-level rise, thawing permafrost may released quantities methane into atmosphere would contributed OAE rapid warming its characteristic negative carbon isotope excursion. This study offers hypothesis how some hyperthermal be rooted “cold-snap” episodes.