Conifer woods from the Salamanca Formation (early Paleocene), Central Patagonia, Argentina: Paleoenvironmental implications

BREA, MARIANA; RAIGEMBORN, M. SOL; RUIZ, DANIELA P.; MATHEOS, SERGIO D.

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2017 vol. 76 p. 427 - 445

0895-9811

The main objective of the present work is to describe the first conifer assemblage of a mixed forest from the Danian Salamanca Formation in the Estancia Las Violetas locality (San Jorge Basin, Central Patagonia, Argentina), based on detailed descriptions of secondary xylem. Also, sedimentological description of the Estancia Las Violetas outcrops are made with the aim of interpret the paleoenvironmental conditions under which paleocommunities developed. Six conifer woods are described and assigned to one Podocarpoxylon Gothan and three Cupressinoxylon Göppert species (including a new species). This is the first record of Patagonia forests where the conifer assemblage is dominated by Cupressinoxylon, associated with Podocarpaceae and palms (recorded asfruits), conforming a mixed forest with a floristic composition similar to present-day New Caledonia forests. Las Violetas fossil forests represent a parautochtonous community developed in a forested coastal setting, a tide-dominated estuary, at ~ 51?50° S paleolatitudes of South America during the early?middle Danian.