Eustatic Control on Early Dolomitization of Cyclic Peritidal Carbonates: Evidence from the Early Ordovician Upper Knox Group, Appalachians and Middle to Late Cambrian Bonanza King Formation, Southern Great Basin

Abstract

The origin of massive dolomite in ancient cyclic carbonate successions remains a poorly resolved issue reflecting the lack of modern analogs of extensive dolomitization. This paper presents evidence for extensive synsedimentary dolomitization of peritidal cyclic carbonates of the Early Ordovician upper Knox Group, Appalachians, and of the Middle to Late Cambrian Bonanza King Formation, southern Great basin. Early dolomitization of these Cambro-Ordovician carbonates was synchronous with regressive conditions governed by superimposed sea-level oscillations (fifth-, fourth-, and third-order).