f;i,.\riAL i»i:i'<>sn's in I'l.xi': ui\i:ii v.\i.i,i:v 



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Till" (able-flats at Florida, cast of Duraiifio. ("ulorailo. (.11 the Denver & 

 Kic (Jraiule Railway and eastward across I'ine river to beyond Si»rin« creek 

 at I.aboca on that railroad — in fact, the whole area from the bluff-mesas 

 west of Durango to the bluff-mesas beyond Spring creek to the eastward in 

 a curve running to the northeast of Durango and bending far to the south- 

 ward and southeastward, is covci-cd heavily with glacial drift, except 

 where the country rocks i>ro.jcct abo\-c it in iioints. ritlges. and buttes in 

 many places. The mesas southwest of Ignacio are also covered with 

 glacial boulders and other glacial material. Ilow much farther the ghicier 

 extended is not known to the writer. 



A little northeast of Durango in the Animus valley there are heavy 

 morainic deposits, associated with extensive outwash deposits. The same 

 phenomenon appears on the Florida, above and in the vicinity of the station 

 of the same name. At Oxford the outwash matei'ial, loess, etc. is ten feet 

 deep, superimposed on a bed of boulders often from ten to twenty feet in 

 depth. West of Ignacio the outwash material butts up against the mesas, 

 being often twenty feet thick in the valleys. At Ignacio and at the South- 

 ern Ute Boarding School a mile to the northward, the outwash and 

 upper till loess and adobe clay is from five to ten feet deep back from the 

 mesa's edge of the first bench. Immediately underneath this are from five 

 to twenty-five feet of boulders luulerlain in places by lower till. At Laboca 

 only outwash material was seen, there often forty feet thick, as is shown 

 in the valley cuts of the present washes. 



Three miles north of the present Indian school on Pine river, the stream 

 has cut completely through the debris, which here shows no lower till, 

 but twenty-five feet of boulders on which are superimposed outwash till and 

 loess. The bench west of the boarding school, to which a part of the .school 

 land extends, is one hundred feet above Pine river in elevation, but at no 

 place in the slopes from the river to its crest is the original rock shown. 

 On top of the bench are five feet of adobe, beneath which are twenty-five 

 feet of boulders, and under this till to an unknown thickness. At Bayfield, 

 ten miles north of Ignacio, the outwash material is of immense thickness, 

 overlying boulders; while to the southeast of that city over a small ridge of 

 jutting, origiiml country rock buttes, is a pocket of glacial deposits of a 

 similar nature. Also from Bayfield northward on Pine river for many miles, 

 outwash material is very conspicuous. The valley fillings seem to be 

 composed wholly of it. 



The glaciers that made these deposits seem to have had two or more 

 centers. The glacier in the vicinity of Durango appears to have come down 

 the Animus river channel. The rest of the glaciers seem to have had their 

 origin in the lake country above the jtuiction of Vallecieto creek and IMiu? 

 river in the high peaks of the San .luau range. Pushing downward from 



