Downloads of the Dynamic Digital Map
of Holtwood PA (DDM-HoltwoodPA)

(Cross-Platform Stand-Alone Programs Made with Revolution)

Kendra Clark
Department of Geosciences
University of Massachusetts-Amherst

Links to download the latest cross-platform, web enabled versions of the Dynamic Digital Map of the Holtwood Pa (DDM-HoltwoodPA) are found below.

Spectacular outcrops of brittle fractures are present in southeastern Pennslyvania, just below the Holtwood Dam on the floor of the Susquehanna River. These outcrops are the largest nearly continuous exposure of the crystalline rocks of the Central Piedmont. While the Paleozoic Wilson Cycle of the Appalachians and the complex fracture history of the younger Mesozoic Basins are reasonably well known, data for brittle fractures indicate a more complex younger history of the Piedmont rocks of the Central Appalachians. No one has studied in detail the brittle fracture history. This is surprising as brittle fabric has many implications for groundwater and engineering applications, tectonic history, and current seismic patterns.

The purpose of this Dynamic Digital Map is to (1) provide a visual tour of the field study area, (2) present details including various map products, images, and data in a dynamic and interactive way and (3) create a format for future study of the area.

The downloads are standalone programs that run without other software. The programs access their data [maps and images (in jpeg format), and movies] from a file server at UMass, using the web to transfer the images, thus requiring fast internet connections. All DDMs can access data from CDs or Hard Drives, if the data is available in those locations. To see any included movies, both Windows and Mac based computers must have the latest QuickTime Player installed (free from Apple for both platforms, at www.apple.com). Computers with less than 128 MB of free RAM will run these programs very slowly at best.