Abstract The Fremont River drainage basin has a variety of geologic and geomorphic features that provide insight into the long-term landscape development of the catchment. Volcanic rocks that are ca. 26 to 4 Ma and are offset by Basin-and-Range style normal faulting underlie the western third of the drainage basin. Fish Lake Hightop and Boulder Mountain show evidence of Pleistocene glaciation. Recent mapping and surface exposure dating suggests that the glacial deposits around these two mountains were deposited during the last glacial maximum (LGM). Mass movement and fluvial deposits in the catchment are predominantly composed of volcanic boulders derived from the volcanic rocks atop Boulder and Thousand Lakes Mountains. Fremont River and tributary incision rates estimated from surface exposure dating of these deposits range from 0.20 to 0.43 m/k.y. Longer-term estimates of exhumation rates in the drainage basin based on emplacement depths of igneous rocks range from 0.10 to 0.38 km/m.y.

Abstract From a high point on the south side of the Platte Valley, 4.7 mi (7.5 km) west of Fremont (Fig. 1) and 1.8 mi (2.9 km) north of Cedar Bluffs (SE½SE½ Sec.22, T.17N., R.7E.; Fremont West 7¼-minute Quadrangle), one can view the present Platte River and valley as well as look across an abandoned valle segment through which at least part of the Platte River once flowed (Fig. 2). In addition, the south bluffs of the Platte, which have remained cleanly swept exposures of a large partof the Pleistocene record of eastern Nebraska since before 1900, can be seen from across the river in Hormel Park (N edge SW½Sec.34, T.17N., R.8E.) (Fig.3). To reach the overview point, follow Nebraska 109 north from Wahoo to Cedar Bluffs, go east 0.25 mi (400 m), then north 2 mi (3.2 km) to County Road 2. Turn west 0.1mi (0.2 km) and stop at the top of the slope (Fig. 1). To reach Hormel Park in Fremont, return to Nebraska 109 and turn east 5 mi (8 km). At U.S. 77, turn northfor 1.5 mi (2.5 km), then west 0.4 mi (0.6km). Follow the gravel road to the southwest about 0.2 mi (0.3 km)to Hormel Park. Drive about 0.2 mi (0.3 km) farther, park, and walk to the edge of the Platte River. Field glasses are useful to examine the bluffs, which are across the river, about 600 ft(200 m) away. Both the overview point

Abstract The Fremont Lake area is at the southwest base of the Wind River Range, northeast of the town of Pinedale in Sublette County, Wyoming, (Fig. 1). It is included in the Fremont Lake South Quadrangle (scale 1:24,000) for which a topographic map, a geologic map (Richmond, 1973), and a soils map (Sorenson, 1986) are available. The area is accessible from Pinedale on U.S. 191, about 100 mi (160 km) north of Rock Springs and 70 mi (112 km) southeast of Jackson. County Road 23-111 (paved) leads northeast from Pinedale into the area. Most of the terrain is in Bridger National Forest, but some is private land. All maintained roads are accessible by passenger car. Many unimproved roads require four-wheel drive. Obtain permission to enter gated roads. Respect signs; close all gates unless found open; and do not drive into areas under irrigation. For a short tour, take County Road 23-11 f from the east end of Main Street in Pinedale toward Fremont Lake. The road leads up a terrace front, passes a cemetery, and extends northeast across gently rolling Bull Lake end moraines to an S-curve 2.2 mi (3.5 km) from U.S. 191. Here, the road ascends the steep, very bouldery front of the outermost Pinedale end moraine. Park at the bottom and walk 50 yd (46 m) up the road to a cut where Pinedale Till is well exposed (locality A, Fig. 1). Drive on to the moraine crest, from which an out standing overview of Fremont Lake, the enclosing Pinedale