EELATIONS OF HIGH PLATEAUS TO PLATEAU PROVINCE. 9 



now, and every branch and every twig of a stream runs in cafions. The 

 land is thoroughly dissected by them, and in many large tracts so intricate 

 is the labyrinth and so inaccessible are their walls, that to cross such regions 

 except In specified ways is a feat reserved exclusively to creatures endowed 

 with wings. The region at levels below 7,000 feet is a desert. A few 

 miserable streams meander through it in profound abysses. The surface 

 sj^rings will not average one in a thousand square miles, for the canons in 

 their lowest depths absorb the subterranean water-courses. But in the 

 High Plateaus above we find a moist climate with an exuberant vegetation 

 and many sparkling streams. 



RELATIONS OF THE HIGH PLATEAUS TO THE PLATEAU PROVINCE AT LARGE. 



It is impossible to gain any {adequate conception of the broader and 

 more general features of the High Plateaus apart from their relations to the 

 Plateau Province at large. The geological history of the district is insepara- 

 ble from that of the province of which it is a part, and that history is full of 

 interest and instruction. Beyond Cretaceous time it is unfortunately vague 

 and uncertain at present; and even during the Cretaceous our knowledge is 

 limited as yet to a few salient facts too conspicuous to be overlooked, but 

 of very great geological importance. We now know that during Cretaceous 

 time the ocean stretched from the Wasatch to Eastern Kansas, Nebraska, 

 and Dakota, and from the Gulf of Mexico far northwards toward the Arctic 

 Circle. The area now occupied by the Great Basin was then a large island, 

 or possibly a portion of some unknown continental mass. East of it proba- 

 bly lay numerous islands. Around the southern border of this area the 

 Cretaceous ocean joined the Pacific, covering the entire extent of the Plfiteau 

 Province and more to the southwestward. We find throughout the plateaus 

 vast bodies of Cretaceous stata which seem in a general way or collectively 

 to correspond with those which have been studied and described by Meek 

 and Hayden in the Great Plains of Nebraska, Dakota, Montana, Wyoming, 

 and Colorado, and by Newberry in New Mexico and Arizona. Although 

 the subdivisions of the Plateau Province havfe not been wholly con-elated 

 with the marine Cretaceous of the other temtories north and east, tliere 

 can be little doubt that the series as a whole agrees in general. The lower 



