254 C. Stock — Cenosoic Mammalian Remains 



The beds rest unconformably upon the older series and 

 are tentatively considered to be of Pliocene age. These 

 are the deposits referred to below as the Muddy Valley 

 Beds. 



Occurrence. 



Within the confines of the Meadow Valley region of 

 southeastern Nevada at least two areas are known where 

 well exposed sedimentary deposits^ presumably of the 

 later Cenozoic, have yielded mammalian remains. The 

 northern area comprises Meadow Valley, an intermontane 

 enclosure bounded on the west by the Highland Range, 

 on the east and south by the Mormon Range, and on the 

 north by the Pioche Range. Some 80 miles to the south of 

 Meadow Valley, a second series of mammal-bearing beds 

 flanks the southern extremity of the Mormon Range and 

 is exposed in the valley of the Muddy River. Both areas 

 lie within the drainage basin of the Colorado system. 



Meadoiu Valley. — The later Cenozoic sedimentary 

 deposits of Meadow Valley extend for approximately 

 twenty miles north of the entrance to Meadow Valley 

 Canyon and in a lateral extent reach perhaps a distance 

 of ten miles or more. They are typically exposed near 

 the village of Panaca. These beds rest unconformably 

 upon older rocks of Paleozoic, Mesozoic, or early Tertiary 

 age that form the borders of the valley. The deposits 

 consist in part of red-brown and green colored sands and 

 clays, not well indurated, exhibiting on their weathered 

 slopes typical badland features. Cross-bedded sands 

 and gravels as well as tuffaceous materials are also pres- 

 ent. The sediments have either a horizontal position or 

 show the effects of slight deformation. Meadow Valley 

 presents striking physiographic features as a result of the 

 terracing which the later Cenozoic beds have undergone. 

 Fossil materials pertaining to a camel, a rhinoceros, and 

 a horse were collected in exposures immediately south- 

 east of Panaca. The designation Panaca beds may be 

 conveniently applied to these mammal-bearing sediment- 

 aries of Meadow Valley. 



Muddy Valley. — Terraced sedimentary deposits extend 

 along the Muddy River for some ten miles northeast of 

 the confluence of this stream with the Virgin River. 

 Southwest of Muddy River, between the villages of 



