Fossil woods from the Lower Cretaceous Tres Lagunas Formation of central Patagonia (Chubut Province, Argentina)

Abstract

Silicified fossil woods are common in the Tres Lagunas Formation (Lower Cretaceous) of central Patagonia. This region has a poor record of Early Cretaceous fossil woods. A collection of 23 fossil woods is studied. Fossil wood anatomy is described and compared in detail. The wood flora is composed of conifers. Most of the samples have Araucariaceae-like wood anatomy. The samples are placed into seven taxonomic units: three fossil-species of Agathoxylon, two more taxonomic units related to Agathoxylon, one taxonomic unit consistent with Cupressinoxylon? and one fossil-species of Brachyoxylon. This study indicates a dominance of conifers, particularly Araucariaceae, during the Early Cretaceous of this zone of central Patagonia which partially does not coincide with the taxonomic proportions of previous studies of coeval pollen and plant macrofossils.