TESTING THE PRIMARY EXPRESSION OF THE SHURAM ISOTOPE EXCURSION ACROSS A BASIN TRANSECT OF THE SAN JUAN FORMATION, SOUTHERN PERU

The largest carbon isotope excursion in Earth History is the Shuram, which remains poorly understood in spite of being associated with the rise of metazoans and linked to the geochemical evolution of the Earth's surface in the Ediacaran. New occurrences of the Shuram in locations where its primary signature and synchronicity can be further tested are valuable for understanding the nature and significance of this isotope excursion. From the carbonate-dominated San Juan Formation in southern Peru, we present evidence for the first clear example of the Shuram isotope excursion in South America. We employ a multi-proxy approach through lateral facies changes across a platform transect, to test models of diagenesis and local effects.