Integrated vertebrate, invertebrate and plant taphonomy of the Fossil Forest area (Fruitland and Kirtland formations: Late Cretaceous), San Juan County, New Mexico, USA

Abstract

Outcrops of the upper Fruitland and lower Kirtland formations (Upper Cretaceous) in the Fossil Forest area of northwestern New Mexico, USA, contain abundant organic remains. This fossil accumulation is “typical” of the late Cretaceous of the Western Interior. The vertebrate fauna is characterized by a lack of coprocoenoses or soil accumulations, few bones with evidence of carnivore damage and a paucity of small bones. Macrovertebrate remains are disarticulated and hydrodynamically sorted. Microvertebrate accumulations are all hydrodynamic in origin. Macerated plant material is common in all rocktypes. An extensive fossil forest was preserved as the result of a large flood which drowned a floodplain forest. Invertebrates are mainly restricted to channel-lag deposits. Vertebrate fossils, and to a lesser extent petrified wood, are restricted to a single downcut fluvial complex.