Review of the palaeoenvironmental reconstruction of Late Quaternary marine sequences, Tierra Del Fuego (Argentina)

CANDEL, M.S.; BORROMEI, A.M.

Publicación Electrónica de la Asociación Paleontológica Argentina

Asociación Paleontológica Argentina

Lugar: Buenos Aires; Año: 2016 vol. 16 p. 184 - 201

This work is an updated review of the knowledge on the evolution and development of palaeoenvironments during the holocene marine ingression and posterior regressive event in Tierra del Fuego. During the beginning of the marine transgression, ca. 8,000 cal yr BP, the vegetation in the southern coastal areas along the Beagle Channel was mainly arboreal with dominance of Nothofagus forest and scarcity of shrub and herbaceous communities, while in the northeastern atlantic coast, the treeless steppe was replaced by a relatively open Nothofagus forest. The early?Middle holocene aquatic assemblages were characterized by a scarce occurrence of marine components, especially dinoflagellate cysts, suggesting the development of low energy estuarine environments with low-salinities caused by glacier meltwater discharge. After 6,000 cal yr BP, an increase in the number of aquatic species was observed with dominance of Peridiniales dinoflagellate cysts, indicating the establishment of marginal marine environments with low to moderate salinities and high nutrient levels. During the last 1,000 cal yr BP, the littoral vegetation along the Beagle Channel showed an open Nothofagus forest and the development of peatlands, while in the northeastern atlantic coast the steppe vegetation developed under less humid environmental conditions related to the marine regressive event. These assemblages have a similar composition to those observed in modern sediments of the Beagle Channel and suggest palaeoenvironmental conditions comparable to today.