Keywords: Petrified-wood-11.jpg en Petrified wood from the Upper Paleogene of Rio Negro Argentina es Madera petrificada - Valle del río Ñirihuau Río Negro - Formación Ñirihuau paleógeno superior 25 millones de años own Dhzanette See it also at http //sites google com/site/patagonianfossils/ Virtual Museum of Patagonian Fossils Petrified wood Petrified wood of Patagonia Nature of Río Negro Province |