Annual report of the United States Geological Survey to the Secretary of the Interior . iderable area of earlyPleistocene gravel. The western border of this area has an elevationperhaps 400 feet greater than the portion of the area bordering onWillow Creek. Along most of the rivers are to be found the usual bars, of whichEnglish Bar, on the Middle Fork of the Feather, is a good along the North Fork of the Tuba River, from Indian Valley toSierra City, are gravel banks or bars, some of them as much as 150feet above the present river. There are pebbles of Tertiary volcanicrocks mixed
Annual report of the United States Geological Survey to the Secretary of the Interior . iderable area of earlyPleistocene gravel. The western border of this area has an elevationperhaps 400 feet greater than the portion of the area bordering onWillow Creek. Along most of the rivers are to be found the usual bars, of whichEnglish Bar, on the Middle Fork of the Feather, is a good along the North Fork of the Tuba River, from Indian Valley toSierra City, are gravel banks or bars, some of them as much as 150feet above the present river. There are pebbles of Tertiary volcanicrocks mixed with those of older rocks in these gravels. Downievillerests on Pleistocene gravel, as does also Goodyears Par. There arenarrow areas of these old gravels also extending for several miles alongthe branches of the North Fork of the Yuba north of Dowuieville. EVIDENCES OF GLACIERS. The ridge in the northern part of the area known as the GrizzlyMountains supported a few small glaciers on its eastern slope, but thereappears to be no evidence of glacial action on the western and southern. TURNER.] GLACIAL PHENOMENA. 595 slopes. Houghs Peak is one of the high points of this ridge, lyingnorth of the fortieth parallel. Crystal Lake, which is on the northslope of this point, owes its origin to a terminal moraine. Anothersmaller terminal moraine was noted at the east base of a bluff that lieseast of the peak. On the steep east slope of the ridge at Tower Peakthere are several crescentic masses of morainal material, and on theeast side of Little Grizzly Creek, opposite the mouth of the streamwhich heads at Tower Rock, is a piled-up mass of quartz-porphyry andgreenstone bowlders that appears to be a terminal moraine. Much the finest glacial district, however, is that of the ridge join-ing the Sierra Buttes and Eureka Peak. The east slope of the buttesand the neve basins about Gold, Bear, Wade, and the Jamison lakes arewell polished and scored. So also is the north slope of Eureka Peak, the
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