The Mulde event was an anoxic event, and marked the second of three1 relatively minor mass extinctions (the Ireviken, Mulde, and Lau events) during the Silurian period. It coincided with a global drop in sea level, and is closely followed by an excursion[clarification needed] in geochemical isotopes. Its onset is synchronous with the deposition of the Froel Formation in Gotland. Perceived extinction in the conodont fauna, however, likely represent a change in the depositional environment of sedimentary sequences rather than a genuine biological extinction.
Higher resolution d13C isotope analysis identifies differences in the organic and carbonate carbon isotope curves (D13C), allowing the inference of a sustained drop in CO2 levels coincident with the extinction once sedimentological data are taken into account.
.mw-parser-output .citation{word-wrap:break-word}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}^1 The Ireviken, Mulde, and Lau events were all closely followed by isotopic excursions.
