Abstract The Hudson Valley fold-thrust belt of eastern New York State involves a relatively thin sequence of shallow-marine Silurian and Lower Devonian strata. Because of the thinness of this sequence, structures of the belt are relatively small. Thus, first-order ramps and flats, and fault-related folds can be seen in their entirety at a single roadcut. A field trip in the southern half of the Hudson Valley fold-thrust belt, from the latitude of Catskill to the latitude of Rosendale, provides an opportunity to see many examples of these structures, and to discuss the three-dimensional architecture of fold-thrust belts in an orocline. In particular, we will see how along-strike changes in stratigraphy affect fold wavelength and the depth of detachment horizons. The trip also provides the opportunity to examine the relationship between mesoscopic structures (e.g., solution cleavage and veining) and first-order structures.

Abstract Many of the parks within the National Park System owe their uniqueness to their geologic framework. Their scenery is the result of diverse natural processes acting upon a variety of rocks that were deposited in varied environments in the geologic past. The Delaware Water Gap National Recreation Area (DEWA) contains a rich geologic and cultural history within its 68,714 acre boundary. Following the border between New Jersey and Pennsylvania, the Delaware River has cut a magnificent gorge through Kit-tantinny Mountain, the Delaware Water Gap, to which all other gaps in the Appalachian Mountains have been compared. Proximity to many institutions of learning in this densely populated area of the northeastern United States (Fig. 1 ) makes DEWA an ideal locality to study the geology of this part of the Appalachian Mountains. This one-day field trip comprises two stops within the gap itself and will include discussion on stratigraphy, structure, geomorphology, and glacial geology. The first stop will be at the bottom of the gap in Pennsylvania to look at the magnificent exposures in the cleft on the New Jersey side. This will be followed by a traverse to the top of Mount Tammany along a popular trail, where we will compare the geology across the river in Pennsylvania. Much of the information presented in this guidebook is summarized from Epstein (2001a , 2001b , 2001c ) and Epstein and Lyttle (2001) .

Abstract The Delaware Water Gap National Recreation Area (DEWA) contains a rich geologic and cultural history within its 68,714 acre boundary. Following the border between New Jersey and Pennsylvania, the Delaware River has cut a magnificent gorge through Kittatinny Mountain, the Delaware Water Gap, to which all other gaps in the Appalachian Mountains have been compared. Proximity to many institutions of learning in this densely populated area of the northeastern United States (Fig. 1 ) makes DEWA an ideal locality to study the geology of this part of the Appalachian Mountains. This one-day field trip comprises an overview discussion of structure, stratigraphy, geomorphology, and glacial geology within the gap. It will be highlighted by hiking a choice of several trails with geologic guides, ranging from gentle to difficult. It is hoped that the “professional” discussions at the stops, loaded with typical geologic jargon, can be translated into simple language that can be understood and assimilated by earth science students along the trails. This trip is mainly targeted for earth science educators and for Pennsylvania geologists needing to meet state-mandated education requirements for licensing professional geologists. The National Park Service, the U.S. Geological Survey, the New Jersey Geological Survey, and local schoolteachers had prepared “The Many Faces of Delaware Water Gap: A Curriculum Guide for Grades 3–6” ( Ferrence et al., 2003 ). Copies of this guide will be given to trip participants and can be downloaded from the GSA Data Repository 1 . The trip will also be useful for instruction at the graduate level. Much of the information presented in this guidebook is modified from Epstein (2006) .