INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
Palaeoecology and Palaeoenvironments of Podocarp trees in the Ameghino Petrified Forest (Danian), Patagonia, Argentina
BREA, MARIANA; MATHEOS, S.D.; RAINGEMBORN, M.S.; IGLESIAS, A.; ZUCOL, A.F.; PRÁMPARO, M.B.
Lugar: BARCELONA; Año: 2009
Abstract The Central Patagonia during the Early Paleocene (Danian) was warm-temperate and dominated by evergreen coniferous forest. As an evidence of this type of flora abundant permineralized conifer woods and some dicot and palm compression leaves were found in Ameghino Petrified Forest. All the permineralized woods and large trunks are assigned to Podocarpoxylon mazzonii (Petriella, 1972) Müller-Stoll et Schultze-Motel, 1990. An estimated tree height of 17-29m was calculated on the basis of diameter measures. Based on 14 series and 169 rings, the mean ring width and Mean Sensitivity (MS) were 1.23 mm and 0.19 respectively. The growth rings are moderately wide, extremely uniform and complacent, indicating that the environment was favourable and constant without stress limiting for tree growth. Following the coniferous quantitative outlined by Falcon-Lang, Podocarpoxylon mazzonii growth ring anatomy suggests that these trees have been an evergreen habit. Fossil flora, growth ring and sedimentological analyses suggest that this mostly evergreen coniferous forest developed under warm-temperate conditions without limiting factors.