THE DISCOVERY OF EARLY MIDDLE TRIASSIC DINOSAUR TRACE FOSSILS IN ZHENFENG,GUIZHOU

Five-toe dinosaur trail fossils occur on the bedding surface of muddy dolomite with drying cracks in the lower part of the Middle Triassic Guan- ling Formattion,having an outcropping area of nearly 100m~2.There are a few dozens of pairs of dinosaur tracks,making up three groups of trails of differ- ent directions.The first group includes tracks of front and rear feet and the second and third groups only possess tracks of the rear foot,indicating that the dinosaur was able to walk on four limbs and also merely on its rear limb. The tracks are still in perfect preservation though the surface of the dolomite has been stripped for more than 30 years.The authors propose that the occur- rence of trace fossils should be built into a peculiar geological tourist site on the tourist line of western Guizhou.