Pardee Keynote Symposia

P1. Erosion: Processes, Rates, and New Measuring Techniques

Hickory Run Boulder Field
The Hickory Run Boulder Field, considered to be the largest boulder field in the Appalachian Mountains, lies at the headwaters of Hickory Run in the western foothills of the Pocono Mountains. The Hickory Run Boulder Field is a National Natural Landmark located 1.5 km southwest of the Wisconsin (~20,000 yrs BP) terminal moraine. The un-vegetated part of the unconsolidated boulder field is ~120 m × 550 m in aerial extent, and some of the boulders are as much as 8 m in length (long axis). The depth of the boulder field extends at least several meters. The source of the boulders is two ridges of Devonian Catskill Formation sandstone and conglomerate immediately north and south of the boulder field. The boulder field is dotted with patterned ground features, most noteworthy of which are polygonal pits with raised rims and low centers, which must post-date down slope movement of the boulders from their ridge source areas. A periglacial relict of full-glacial climatic conditions, the boulder field is intriguing because it demonstrates that relatively large amounts of rock can be weathered and eroded from a low-relief landscape given the right climatic conditions and geologic setting.