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Paleontological Assessment • <br />Fossils aze non-renewable and relatively raze resources (except for microfossils and <br />those that make up the energy minerals) with significant scientific, educational, commercial <br />and recreational values. Fossils on federal lands aze managed for their scientific, educational <br />and, where appropriate, recreational values. Geological formations on BLM lands have been <br />categorized for management purposes to indicate those that aze required to have intensive <br />inventories. A Category I formation is one that has previously yielded a high number of <br />fossils and is considered scientifically significant. The Mesaverde Formation in this region has <br />a low occurrence of fossils and does not qualify as "Category I," therefore an intensive survey <br />is not required. Also, the lack of surface exposures of the Mesaverde Formation throughout <br />most of the project's 1640 acres renders its survey for paleontological resources unnecessary. <br />The Late Cretaceous-age Mesaverde Group sandstones and coal-bearing rocks aze the <br />bedrock of the study azea and aze part of the Uintah Field, one of three major coal fields in the <br />region. This group can be subdivided into two subgroupings, one coal-bearing and the other <br />noncoal-bearing. The coal-bearing part includes the Staz Point, Blackhawk, Neslen, Mt <br />Garfield, Iles, and Williams Fork Formations. This area was once a lowland swamp that <br />resembled present-day environments like the Mississippi delta, the Louisiana coastal plains, <br />lagoons and swamps, and the Everglades. One ofthe characteristics ofthis part is its <br />abundant beds of carboniferous shale and coal produced from the vegetation of the great • <br />swamps, which included a mixture of ferns, gymnosperms, and angiosperms. These plants <br />were eaten by dinosaurs, and these kinds of formations have produced skeletal-rich deposits in <br />many azeas of the world. However, acid conditions of the waters that seeped through the <br />plant-rich sediments often destroyed the remains of the animals that lived in the swamps and <br />transitional environments (Young 1987:47). <br />It is best known for fossils of the duckbill (hadrosaurs) and horned (ceratopsians) <br />dinosaurs. In North America, the Two Medicine Formation of Montana, the Judith River <br />Formations of Alberta, and the Lance Formation of Wyoming have produced many of these <br />fossils. In contrast, the Mesaverde deposits of the Colorado, Utah, and Wyoming region, are <br />almost devoid of skeletal remains, but are known to contain abundant tracks (ichnofossils), <br />predominately those of the lazge hadrosaurs. The tracks of the horned dinosaurs aze raze and <br />poorly known, although they aze as common in the skeletal record as the hadrosaurs. <br />Paleontologists speculate that this marked difference suggests that the ceratopsians may have <br />avoided the environments frequented by the hadrosaurs (Lockley 1991:100). <br />In west central Colorado, the most common vertebrate fossils of the Mesaverde aze <br />those found on the tops ofcoal beds. In a study ofthe Grand Junction Resource Area, <br />Armstrong and Kihm reported finds offish, turtle scutes, crocodile scutes and bones, and <br />innumerable dinosaur tracks in the Book Cliffs north of Grand Junction (Armstrong and Kihm, <br />1980). The most unusual find in the formation is a nest of dinosaur eggs of an unidentified <br />type that was reported from the Roadside Mine at Cameo, north of Palisade. • <br />