64 C. D. WALCOTT — A DISPLACEMENT IN THE GRAND CANON. 



on the rising slope of'the fold, I am inclined to think thai the Blight move- 

 ment ni' this time was going on «1iiiIii ;_r the latter part of the deposition of 

 the Permian. 



^^mmrmm 





A 

 l he 12.— Diagramatic Section of the Permian Monocline. 



Illustrating tin- thinning out of the upper Permian and the shinarump conglomerate against the 

 more highly inclined Permian strata beneath. (The ancient Permian cliff i- i by del 



at the immediate base of the section.) 



It is probable that the era of the deposition of the Permian was one of 

 slow movement of the sea-bed. Elevation and depression are indicated by a 

 strongly marked unconformity, by erosion, in the lower portion of the upper 

 Permian. This is shown by the unconformity in the Permian so well seen 

 in the buttes south of the Shinarump cliff, eleven miles Bouthwesi of Kanal>. 

 Utah. The sediments arc mostly detrital in character, and ripple-marks 

 and other indications of a littoral deposit are also seen at several horizons. 

 The evidences of the movement do not indicate that it was of great magni- 

 tude, l»nt rather the contrary. Sufficient is shown to prove that the incep- 

 tion of the great Tertiary displacement was in Paleozoic time. 



From the close of the Paleozoic to the Middle Tertiarv there is no known 

 evidence of any movement along the line of the East Kaihah displacement. 

 Tin- intervening time appears to have been one of slow subsidence and quiel 



deposit! f sediments. From the evidence given by Captain Dutton* it 



i- scarcely to he doubted that the later displacements are of Tertiary age, 

 and that tli-' movement continued to a comparatively recent date. 



/,'■ wme. — The history of the displacement IS briefly staled as follow-: 



The Easl Kaihah movement began in the region of the Grand Caftan as 

 a pre-Cambrian faull displacing the older Algonkian strata, with a down- 

 throw to the west of from LOO to 1,000 feet. A period of rest then ensued 

 thai was broken, in the latter pari of Paleozoic time, by the formation of 

 an eastward-facing monoclinal fold of a few hundred feet. So far aa known 



this movement ceased with the close of the Paleozoic, and Was not resumed 



until Tertiary time. It tben began and continued until the Easl Kaihah 

 fold and the accompanying faull were developed ; the displacement aggre 

 gating over 2,700 feel in the vicinity of the Grand Caftan. This occurred 

 before the removal, by erosion, of the Permian and probably more or less 

 superjacent strata over the Grand ('anon area. 



I. -', with artia I Cafioi 



