CHAPTER X. 
GEOLOGY OF THE ROUTE FROM SANTA FE TO FORT LEAVENWORTH. 
GENERAL FEATURES OF THE COUNTRY.—FERTILITY OF THE MISSISSIPPI SLOPE.—CONTRASTING ASPECTS OF THE MOUNTAIN REGION AND SEA~ 
LIKE PLAINS. —ANALYSIS OF THE DIFFERENCES BETWEEN THE PLATEAUS WEST AND EAST OF THE ROCKY MOUNTAINS.—1HE CAUSES, BOTH 
EXTRANEOUS : G GRANITIC AXIS EAST OF SANTA FE.—CARBONIFEROUS 
LIMESTONES, &C —GyYPSIFEROUS SERIES IN APACHE CANON AND THE VALLEY OF THE PECOS.—SECTION AT PECOS CHURCH.—OJO VERNAL.— 
Cars. LiwesTone.—LAs VEGAS.— UPPER CRETACEOUS STRATA.—LAS VEGAS TO THE CIMARRON.—LOWER CRETACEOUS SANDSTONES.— TRAP 
OF THE RATON REGION.—UPPER CRETACEOUS STRATA AND FOSSILS ON RED RIVER.—PATCHES OF TERTIARY LIMESTONE.—TERTIARY BASIN 
OF THE ARKANSAW.— HiGH PRAIRIES.’—PAWNEE FORK TO COUNCIL GROVE.—CRETACEOUS SANDSTONE.—JURASSIC AND TRIASSIC BEDS 
OVERED.—FIRST TRUE PERMIAN STRATA SEEN.—COUNCIL GROVE TO FORT LEAVENWORTH.—PERMIAN AND CARBONIFEROUS ROCKS.— 
CARBONIFEROUS FOSSILS.—FUSILINA LIMESTONES.—KANSAS SECTION OF MEEK AND HAYDEN. 
The general features of the country traversed between Santa Fé and the Missouri may be 
very briefly described. For seventy-five miles after leaving Santa Fé we were involved in the 
spurs of the Rocky mountains, and were passing through a remarkably picturesque and beautiful 
region, in which the surface is nearly equally shared between rocky, ragged, and pine-covered 
sierras, and open, grassy valleys, through which flow streams of the purest water, fed by the 
melting of the snows. In this interval we crossed the rim of the great Mississippi valley, and 
began to descend its western slope—a period in our experience marked by many agreeable 
incidents. The soil became more fertile, the vegetation more general and varied; and for the 
first time in our long eastward march familiar faces began to meet us in home species of trees 
and flowers. The noisy mountain streams made music to which our ears had long been 
unaccustomed; and the summer showers by which we were drenched were, for a time, so 
refreshing a novelty that we scarcely cared to avoid them. By all these and other signs we 
saw that we were emerging from the vast arid area in which many preceding months had been 
passed—where sterility is the rule and productiveness the marked exception—and were 
approaching a region where a flowing stream is not a wonder, and where an unbroken sheet of 
vegetation covers the soil. 
_ The geological structure of this section of our route is scarcely in any respect different from 
that of the country immediately west of the Rio Grande. The Coal measure limestone is the 
lowest stratified rock exposed. This is brought to the surface in several localities, and rests 
upon the granite. Over the Carboniferous rocks the Red sandstones, the Variegated marls, and 
the yellow Cretaceous sandstones are shown in many fine sections, among which those of the 
Apache cafion, at Pecos and Ojo Vernal deserve special mention. 
At Las Vegas we for the first time met with unmistakable Upper Cretaceous strata resting 
upon the yellow sandstone group so often mentioned. 
We here stood on what seemed the shore of a boundless sea; behind us the forest-covered 
hills through which we had passed rose, step by step, till lost in the distant snow-covered 
mountains; before us a green and grassy plain, rising in gentle undulations, stretched away as 
far as the eye could reach. North and south a shore line showed many bold and wooded head- 
lands, separating bay-like indentations. In the offing several isolated buttes rose abruptly from 
the surface like so many rocky islands. This was our first introduction to the ‘ Plains,’’ as 
they are commonly called, over which our road lay for more than seven hundred miles—the 
dest, and smoothest in the world, but almost as monotonous as the path of a ship 
aad 
trast which the smooth and unbroken surface, the long and gentle swells, the uniform 
