image: This is a Toarcian ammonite from the Alberta study section. view more
Credit: PNAS
Using thallium isotope records from the Early Jurassic, around 183 million years ago, researchers report that the marine deoxygenation that culminated in the Toarcian Oceanic Anoxic Event began approximately 600,000 years before and extended past the classically defined oceanic anoxic event and that the earliest onset of marine deoxygenation coincides with the initial phases of volcanism thought to have triggered the event and simultaneous marine extinctions, suggesting that thallium isotope data can offer a nuanced view of ancient marine oxygen content.
Article #18-03478: "Thallium isotopes reveal protracted anoxia during the Toarcian (Early Jurassic) associated with volcanism, carbon burial, and mass extinction," by Theodore R. Them et al.
MEDIA CONTACT: Theodore R. Them, Florida State University, Tallahassee, FL; tel: 1-607-725-1208; e-mail: <tthem@fsu.edu>
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