Sedimentology and petrography of a lower Cambrian transgressive sequence: Altona Formation (Potsdam Group) in northeastern New York

clature and ages of the basal sandstone units that outcrop in the St. Lawrence lowlands and Champlain Valley of New York, Quebec, Ontario and Vermont, (e.g., Landing et al. 2009, Sanford & Arnott 2010, Lowe et al. 2017) there is a need for detailed description and interpretation of the stratigraphy that records the onlap of the Laurentian Craton in the Cambrian. While Landing et al. (2009) identified fossils and generally described the Altona Formation as a shallow marine deposit, the greater detail of section measurement and description in this study permit more refined environmental interpretations. This study presents detailed compositional and sedimentologic descriptions and interpretation of the Altona Formation, the basal transgressive unit in the Cambrian sequence in the region northeast of the Adirondack Massif. We hope our data will shed light on regional paleogeographic questions, such as provenance and sediment transport patterns and regional correlations. Regional stratigraphy and geologic setting