Precambrian successions that have the spatial resolution to illustrate the transition from proximal shallow marine environments to deeper water, basinal environments through time are rare. Here, we present a multidisciplinary study of the presalt Precambrian succession of Oman, in both cores and outcrops, and provide a new correlation for the surface type sections to the subsurface. The ∼2000-m-thick proximal, shallow marine Nafun-base Ara Group’s Ediacaran-type section (Huqf outcrops, central Oman) is correlated to new, near-continuous cores of the ∼800- to 1000-m-thick basinal succession in the subsurface of south Oman. We have used sedimentology, sequence stratigraphy, well logs, and carbon isotope chemostratigraphy for correlation and built new depositional models and paleofacies maps. Our updated paleofacies maps support Ediacaran Nafun deposition controlled by regional thermal subsidence along a passive margin on the eastern side of the Mozambique Ocean. Progressively restricted marine conditions in the latest Ediacaran to early Cambrian led to Ara Group evaporitic deposition in a syntectonic convergent margin setting. Shallow-water carbonate deposits of the Khufai and Buah Formations in northeastern Oman and in Birba Formation carbonates on tectonically controlled highs across Oman retain porosity in many instances. The most organic-rich rocks are found in basinal deposits of the Masirah Bay, Khufai, Buah, and Birba Formations in southwestern and western Oman, whereas the Shuram Formation is notably organic poor. Our results add insights into source and reservoir rock distribution and late Precambrian stratigraphy, paleogeography, and tectonic setting in Oman with global relevance.