Palynological and sedimentological analysis of Recent sediments from Río Varela, Beagle Channel, Tierra del Fuego, Argentina.

GRILL S.; BORROMEI, A.M.; QUATTROCCHIO, M.; CORONATO A.; BUJALESKY, G.; RABASSA J.

Revista Española de Micropaleontología

Instituto Geológico y Minero de España

Lugar: Madrid; Año: 2002 vol. 34 p. 145 - 161

A Holocene sequence at Río Varela (54° 52? S lat., 67° 11?W long.), Beagle Channel is studied, taking into account the palynofacies and sedimentology analysis. The recognized seven palynofacies (Palynofacies A to G) plus lithological and sedimentological features permit to establish different paleoenvironments from the base to the top of the sequence : - marine, near shore and low energy environment (Unit 1, Palynofacies A, 6240 ± 70 yr B.P.), with high nutrient supply, relative low salinity and cooler sea water temperature under wet and cold conditions, following outer neritic environment (Unit 2, Palynofacies B) with less humid and warmer conditions; - continental, lacustrine (Unit 3, Palynofacies C) reflecting a relative lower sea level under somewhat drier and possibly warmer conditions ; -  marshy (Unit 4, Palynofacies D, 6060 ± 70 yr B.P.) indicative of relative increase of the sea level under more humid and cooler conditions ; - fluvial to estuarine (Unit 5, Palynofacies E) associated to relative low sea level under humid and cold conditions ; - meander rivers environment (Unit 6, Palynofacies F) associated to relative climatic deterioration ; - soil (Unit 7, Palynofacies G) indicative of  actual conditions.