498 / HARLEN BRETZ 



surface of the fine, light-colored silt which floors this part of the Yakima VaUey. 

 Upper limit 1,200 ft. A.T. These erratics occur in groups, several kinds of 

 rock in each group. Both rounded and angular, and both large and small 

 fragments occur in every group. 



Snipes Mountain, Wash., between Granger and Sunnyside. Foreign 

 cobbles and bowlders common, scattered over the hillside up to nearly 1,200 ft. 

 A.T. One granite, 2 X3 X4, at 950 ft. A.T., has a flat, beautifully striated face, 

 3X4 ft., undoubtedly a glaciated surface. 



Toppenish Ridge and Satus Valley, Wash., 5 to 8 mi. south of Toppenish. 

 A striated quartzite bowlder, associated with granite and other foreign material, 

 at about 1,100 ft. A.T. A granite bowlder at 1,100 ft. on the south side of the 

 Satus Valley. 



Ahtanum Ridge, Wash. (10 mi. S.S.W. of Yakima). Large numbers of 

 angular granite and quartzite bowlders and cobbles on the southern slopes, 

 below 1,200 ft., and on the floor of the structural valley immediately south. 

 Grouping of angular fragments indicate that some original bowlders were 4 

 to 5 ft. in diameter. Material fresh, affected only by frost action and temper- 

 ature changes. One bowlder along road, about midway between Yakima and 

 White Swan, is clearly smoothed and striated on one face.^ 



Dry Creek Valley, Wash. Glacial material plentiful ; granite predominant, 

 but quartzite, diorite, slate, etc., present. Observed upper limit about 

 1,100 ft. A.T. Grouped in the familiar fashion: large and small, rounded and 

 angular, all together except where slope wash has strung them out. Groups 

 separated by intervals of hundreds or thousands of feet where no debris of 

 this sort is to be found. Glaciated surfaces on some bowlders. 



Cold Creek Valley, Wash. Situation similar to that in Dry Creek Valley 

 1,130 ft. maximum altitude observed. 



Priest Rapids, Wash. (4 mi. northwest of). Granite bowlders lie on thfe 

 slopes of the Columbia VaUey up to 1,175 ft. A.T. The highest found is 

 3X4X6 exposed, probably larger. Several nearly as large at 1,150 ft. A.T. 

 on the same hill. Granite is like that in the Arlington bowlder. 



Quincy and Burke, Wash. Between these two places 10 or 12 foreign 

 bowlders were seen at altitudes above 1,200 ft. Two are described as follows: 

 (i) six mi. south of Quincy; granite bowlder, 4X5X 10 exposed dimensions, of 

 the famihar basic igneous rock in a light-colored granite. (2) five mi. south of 

 Quincy; granite bowlder, largely buried, exposed portion 12 ft. long; the 

 largest and the highest (1,255 ft. A.T.) found by the writer. 



Wenatchee Valley at junction with Columbia Valley. Russell reports 

 "great quantities of angular bowlders, some of them of large size, composed 

 principally of quartzite, granite and schists .... about Wenatchee and 



^ George Otis Smith, in Ellensburg Folio No. 86, U.S. Geol. Surv. (1903), notes 

 the presence of erratic bowlders in Wide Hollow and Wenas Valley, north of Ahtanum 

 Ridge, and says they "must have been dropped from masses of ice floating in the 

 ponded waters of Yakima Valley. " 



