Comparison Of Air Photo Lineations And Joint Patterns Dartmoor Southwest England

Comparison of Air Photo Lineations and Joint Patterns, Dartmoor, Southwest England

Joint spacing and orientation data were collected at 58 sample sites in the field. Lineations delineated on 1:24,000 and 1:50,000 scale air photo mosaics were digitized, and orientations of and spacings between lineations were determined using a Geographic Information System (CAPIR). Common trends for lineations on both photo mosaics and from outcrop are east-northeast (40-90) and west-northwest (300340). Thus, lineations from the air photos and the fractures in outcrop probably comprise samples from the same population, but different individuals are seen at each scale: as scale decreases, visible lineations become increasingly longer and more widely spaced. Although the joint and lineation spacing distributions are significantly different from each other, the three distributions have similar modes (100 + 25). Weaker modes are similarly located near even 100's for all three distributions, suggesting spacing may be periodic. Spacing between fractures increases for similar orientations with decreasing scale. The scale independence of these fractures suggests they are fractal in nature.

Bibliography of In-house and Contract Reports

The Environmental Legacy of Military Operations

U.S. military lands are part of the public trust and the level of awareness of sustainability and land-use issues has risen significantly in recent years. Ehlen (U.S. Army Engineer Research and Development Center) and Harmon (U.S. Army Research Office) present 14 articles that look at the use of engineering geology principles and their applications to both military operations and environmental issues, although military operations and the environment are not always treated together. Topics include battlefield terrain evaluation, predicting fracture systems in enemy underground facilities, the geoenvironmental legacy of the Rock of Gibraltar military engineering, and erosion trends at Fort Leonard Wood. Annotation c. Book News, Inc., Portland, OR (booknews.com)