Conference Papers

The U.S. Geological Survey is participating in a joint effort with the University of Maryland Baltimore County and other government agencies to construct a dynamic database of urban development for the Baltimore-Washington region from the late-1700's to the 1990's. The multi-theme temporal database includes a principal transportation data layer that documents the primary roads, railroads...

The U.S. Geological Survey (USGS), in partnership with the University of Maryland Baltimore County, is using historical maps and satellite images to map human-induced land transformations for the Baltimore-Washington metropolitan area. This work builds on an earlier effort that documented the historical urban development for the San Francisco Bay area. That effort used a geographic...

To assess the presence and distribution of a variety of hydro-phobic chemicals in streams in the Red River of the North Basin, bottom sediments were analyzed for trace elements, organochlorines, and polycyclic aromatic hydrocarbons (PAHs). Glaciolacustrine clays and carbonate minerals are common in fine sediments of the region, and can help explain the distribution of many elements...

No abstract available.

Many United States federal agencies need accurate, intermediate scaled, land cover information. While many techniques and approaches have been successfully used to classify land cover in relatively small regions, there are substantial problems in applying these techniques to large multi-scene regions. An evaluation was conducted of the multiple layer land characteristics data base...

Palynological and paleobotanical research on upper Pliocene sediments from Meighen Island, Kap København, and deep-sea sites in the North Atlantic Ocean has indicated the presence of forest tundra far north of its present limits and warmer conditions than present. New pollen data from samples obtained on Ocean Drilling Program Leg 151 (Sites 910 and 911) on the Yermak Plateau of the...

The Human Induced Land Transformation project (HILT), part of the U.S. Geological Survey Global Change Research Program, has generated considerable public interest during the first two phases of the project: the data assembly and visualization phase carried out for the San Francisco Bay area; and the model building and calibration phase. The third phase, now underway for the Washington...

Recent efforts by scientists and managers to inventory, map, and model impacts of human activities on the environment have focused on land transformation and urbanization processes. To test the efficacy of any single model, algorithm or procedure which defines land transformation processes a standard database calibration reference resource is required. Therefore, a set of georeferenced...

No abstract available.

The U.S. Geological Survey (USGS), the University of Maryland Baltimore County (UMBC), and the U.S. Bureau of the Census are working together as a multiagency, multidisciplinary team in developing a temporal database that documents the growth of the Baltimore-Washington metropolitan region. This database consists of urban development, principal transportation, shoreline, and population...

Several lessons about the process of calibration were learned during development of a self-modifying cellular automaton model to predict urban growth. This model, part of a global change research project on human-induced land transformations, was used to predict the spatial extent of urban growth 100 years into the future. The context of the prediction was to evaluate urban environmental

A comparison of mean-random vitrinite reflectance (R(v-r)) values calculated from measurements on polished whole-rock and on concentrates of dispersed organic matter (DOM) mounts of the same samples generally show little difference. Compared to measurements on DOM mounts, R(v-r) measurements by the same microscopist on corresponding whole-rock samples are up to a few tenths of a percent...