THE DISTEIBUTION OP THE CRETACEOUS. 
33 
the proper margin of its own terrace no vestige of it appears to the south- 
ward. 
Proceeding eastward to the Kaiparowits the Cretaceous presents itself 
in a manner which is highly significant, and which merits careful examina- 
tion. We have already remarked that the Eocene is wholly absent from 
the interior spaces of the Plateau Country. From the places of its exposure 
in the southern parts of the High Plateaus to the places of its exposure in 
Colorado and New Mexico is an interval of 180 to 240 miles. But while the 
Eocene is wholly wanting in this great intervening space the Cretaceous 
occurs in very large masses, forming probably at least half of the surface of 
the country. The Kaiparowits Plateau is a broad belt of Cretaceous strata 
reaching out southwardly from the Aquarius Plateau and from Table Cliff 
(an outlier of the Aquarius). At a distance of 60 miles from the latter the 
Colorado River cuts right across the Kaiparowits, forming the great gorge 
of the Glen Canon. South of the river the platform resumes its character, 
and the Cretaceous spreads out into great mesas deeply dissected by canons 
tributary to the San Juan. These Cretaceous mesas cover almost the entire 
northeastern quarter of Arizona and reach indefinitely eastward. In truth 
there is little doubt that these strata are the continuation of the Cretace- 
ous formations which overspread the greater part of New Mexico, Texas, 
Colorado, the Indian Territory, and the Great Plains at large between the 
Rocky Mountains and the Missouri River. It is already a foregone con- 
clusion that the Cretaceous sea, which extended from the Gulf of Mexico 
northward towards the Arctic Ocean, also extended west, covering the Pla- 
teau Province, and reached far into Arizona and even into southern Nevada. 
Perhaps it joined the Pacific through a broad strait running between the 
Great Basin area on the north and the sierra country of western Arizona 
on the south. But this we cannot as yet prove, though many facts seem to 
indicate it. At all events if the Atlantic did not join the Pacific here the 
separation of the two oceans was only by a naiTOw belt of land. 
The western wall of the Kaiparowits here marks the limit of the Cre- 
taceous formation. Formerly, indeed, its strata extended much further 
westward, but they have been swept away from the interior spaces of the 
3 & G 
