358 The American Geologist. May, i«97 
of the gypsum b?lt of Marcy's text to the Cave Creek formation, the 
portion indicated as the '-Gi'eat Belt of Gypsum'' on his "'Map of the 
Country on the Upper Red River," and extending from the "Gypsum 
bluffs" and "Gypsum hills," on the North fork of Red river near the 
camps of June 3rd and 4th, to the South fork near the camps of July 
■Ith and 5th, belongs to the Cave Creek, and the section of the bluffs on 
the North fork given by Dr. G. G. Shumard of Plate 5 of the Geology 
of the same report, shows that the formation there has its typical tri- 
partite development. 
The Dog Creek Formation. — The Dog Creek formation persists 
and finds great emphasis in Oklahoma, being more positive there in its 
character than in Kansas, and thicker and more complex than the Cave 
Creek. In central Oklahoma it is a great dolomite formation, lam- 
inated dolomites occupying a considerable part of its thickness. It is 
well displayed at the eastern border of the Cimarron-North Canadian 
Jack sands of Blaine county, particularly so in Chapman's amphithea- 
tre at the head of Salt creek, where it presents a thickness of apparent- 
ly not less than 100 feet. At this locality, a large body of light gray 
laminated dolomites forms its upper or Chapman member, its middle 
and lower parts consisting chiefly of dull red shales with laminae and 
one lamina-built amphitheatre ledge of dolomite. The amphitheatre 
forms a sort of a terrace, or low secondary brow, below the middle of 
the formation. At the Stony hills,* east of Watonga, the thickness of 
the Dog Creek is at least equal to that shown at the head of Salt creek 
and the bodies of thin-bedded to laminated dolomite are similar to those 
seen at that locality, though perhaps containing some thicker courses 
and developed more at the expense of the shale. Thus in central Okla- 
homa the Dog Creek formation differs strongly in character (as in 
southern Kansas it does plainly, though less strikingly) from the forma- 
tions which precede and follow it in the Cimarron series. 
The Kiger Division. — The latest observations on the composition of 
the Cimarron series show that the Kiger division should be restricted 
to Cimarron rocks higher than the Dog Creek. 
During my April trip some observations were made on outcrops of 
this division on the Canadian river, and through that of September, 
some details additional to those already published were obtained re- 
garding the western extension of Kiger rocks in the Beaver and Cimar- 
ron valleys. It is estimated that there are exposed on the Canadian 
river, below the great bends, not less than GOO feet of rocks belonging 
to the Kiger: and westward, higher beds, partly concealed by Cretace- 
ous and Neocene rocks may add to this thickness an unknown amount. 
The exposed thickness of Kiger rocks on the Beaver river and its suc- 
*There are several reasons why Stony Hills is a better name for tliis dolomite for- 
mation than Dog Creek, one of which is that the Dog- creek of Barber county, Kansas, 
is oitenc?d\e6 Monvmenf crpek. A second is that another Dos: creek in Oklahoma, 
nearer to the typical (lolomitoiiovolopinent of tlie formation, like that 1)()«- creek of 
Barber county, cuts cliietiy below the formation. A third is that the Stony Hillsshow 
a splendid development of the rock that is especially characteristic of the formation, 
which the Barber county locality does not. The name should perhaps be changed 
for these reasons. 
