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FIG. 5. A VIEW OF THE WARRENSBURG SANDSTONE AS EXPOSED SOUTH OF HIGGINSVILLE.

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FIG. 7. VIEW OF LOESS ALONG THE ROAD CUT THROUGH THE RIVER BLUFF AT WAVERLY.

It has not been found to rise higher than an altitude of 900 feet above the sea, in the region under consideration. There are three areas in this elevation; two near the Missouri, in township 51 N., 25 W., and one west of Corder. This level corresponds with the altitude of the edge of the loess plain near Mayview.

The thickness of this formation, as near as can be judged from reports of wells and coal shafts, is very rarely over 50 feet on the uplands, and is sometimes not more than 15 or 20. Near the Missouri it is sometimes over 100 feet in thickness. The differences in thickness and in the altitude of the general surface of the little eroded uplands, are traceable to the unevenness of the underlying formations. An instructive view of the loess as developed along the river at Waverly is shown in figure 7 (plate iii.)

The topography of the country is largely influenced by certain characteristics of the loess, which are brought out in its erosion. At first recession of the waters which deposited it, the surface loess, we conceive, was a quite even and almost level plain. Perhaps there were differences in level of a hundred feet in our area, but probably not so great by half. The present streams beginning upon this plain ere long cut down through the loess and into the underlying sandstones and clays. This continued until a base-level of about 700 feet was reached, as has been done by all the streams showing bottoms along their courses. This level is nearly 200 feet below the original plain. In many regions this could not have been done without many cliffs and broken areas being produced too rough for tillage. But in this loess-covered region such features are almost unknown. Everywhere beautifully smooth surfaces and gentle curves adorn the landscape. This effect results from a kind of plasticity in the loess which is traceable to the way it yields to degradation. This degradation is accomplished by subterranean waters, surface waters and winds. The first softens the underlying clays, or frequently the lower part of the loess itself. Then the proneness of the loess to break into columnar portions by cracking vertically, allows each colunm to push

its softened base down and out. In this way cliffs and steep banks gradually change to a succession of steps. Rains loosen the surface portions and wash them into the crevices and tend to fill slight depressions, unless they collect into rills. In the latter case they begin a furrow which may soon become a gully. But the sides of this again will, in time, be gently sloped.

Winds also play an important part in shaping the loess, especially in smoothing it and giving it a rounded outline. The fine particles loosed by frost or drouth are swept like the This influence is rarely marked, but in a great length

snow.

of time doubtless amounts to considerable.

The result is that the loess has crept down and thickly covered all slopes, some of them many feet below its original base, so that it may often seem to a superficial observer to be from 150 to 200 feet thick. This tendency of the loess is of great value to the farmer, for it furnishes a valuable subsoil over the whole region. By reason of its porosity it quickly absorbs the rain, yet it prevents excess of moisture by natural underdrainage. It furnishes a happy medium between clay and sand, is most easily tilled in either wet or dry seasons.

It follows from the above that the loess, as found in valleys and on the lower hillsides, is rarely in its true relation to underlying formations and is apt to be mingled with them. The more instructive sections are to be sought therefore on the uplands.

The Terrace. There is found along the Missouri river at several points in the State a high terrace rising 100 to 125 feet above the stream. No trace of this has been found in eastern Lafayette county, along that stream, but west of Tabo creek a portion appears on our map of quite an extensive terrace rising 60 to 80 feet above the river. Its structure has not been closely studied, but in a general view of the valley it is quite noticeable. It is much eroded.

The Bottoms. Under this head we include both the "Alluvium" and "Bottom Prairie" of Swallow. They have all been formed by the present streams flowing at their present level.

The only difference between the classes mentioned in earlier reports seem to be one of age. The bottoms are noticeable along Davis, Salt and Tabo creeks, sometimes attaining a breadth of half or three-fourths of a mile. Along the Missouri very little bottom land is found in this county, although it is very wide on the north side. Everywhere these lands are rich and valuable, excepting in limited portions which are marshy.

Opportunity has not been found to examine exhaustively the whole area under consideration. There is room for further discoveries concerning the Quaternary formations, but the above will, we believe, give a fairly correct view of the general facts.

STRUCTURAL GEOLOGY.

The geologic structure of the Higginsville sheet is extremely simple. It is well displayed upon the map and section sheet accompanying this report, and only a few words are needed in addition to direct attention to what is there represented. The strata lie conformably upon each other, with the exception of the Warrensburg sandstone, which is uncomfortable upon the members of the Lower and Middle Coal Meas. ures, as already explained. These strata are seen to have a slight northwesterly dip when widely separated exposures are compared, but within limited areas they appear to occupy practically horizontal positions. Thus, along the river bluff, about three miles west of Waverly, the Mulky coal bed is at an altitude of about 760 feet A. T., while about 10 miles further west, at the mouth of the Tabo creek, the altitude of this same bed is about 705 feet A. T. Along the Chicago & Alton railway, the altitude of the Mulky bed south of Corder is about 780 feet A. T., and some ten miles west, near Higginsville, the horizon of the coal referred to the Mulky bed is about 750 feet A. T.

In the south western corner of the sheet there is evidence of a dip to the northwest of the Mulky coal bed and of the immediately associated strata, while the Lexington coal bed remains horizontal. Consequently the interval between the two increases as is exhibited in the cross section N - O, on the section sheet.

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