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Dorothy H. Radbruch-Hall

Publications and source records attributed to Dorothy H. Radbruch-Hall.

7 recordsLinked to original sources
USGS1979

Environmental aspects of engineering geological mapping in the United States

Many engineering geological maps at different scales have been prepared for various engineering and environmental purposes in regions of diverse geological conditions in the United States. They include maps of individual geological hazards and maps showing the effect of land development on the environment. An approach to assessing the environmental impact of land development that is used increasingly in the United States is the study of a single area by scientists from several disciplines, including geology. A study of this type has been made for the National Petroleum Reserve in northern Alaska. In the San Francisco Bay area, a technique has been worked out for evaluating the cost of different types of construction and land development in terms of the cost of a number of kinds of earth science factors. ?? 1979 International Association of Engineering Geology.

Bulletin of the International Association of Engin↗
USGS1977

Gravitational spreading of steep-sided ridges ("sackung") in Colorado

Large-scale gravitational spreading and fracturing of steep-sided ridges in the mountainous area of Colorado are characterized by horizontal linear fissures, trenches, and uphill-facing scarps on tops and sides of ridges. A pronounced north-trending cleft and several minor scarps have split a ridge extending northward from Dolores Peak in the San Miguel Mountains of southwestern Colorado. This ridge is capped by granogabbro of a Tertiary laccolith that intruded the Cretaceous Mancos Shale. Numerous active landslides in shale mantle the once glaciated lower slopes. Trenches in the granogabbro probably originated after glacial ice melted, leaving steep sides of the ridge unsupported. The soft Mancos shale moved outward toward the direction of least stress, placing the overlying granogabbro under tension. A ridge that extends southwest from Bald Eagle Mountain, north of Mount Massive in central Colorado, is marked by a graben on the top and several trenches on the northwest side, parallel to the long axis of the ridge. Rock exposed in graben and trenches is the Precambrian St. Kevin Granite, which includes some schist and migmatite. Gravitational movement probably took place after steepening of the valley sides by glacial erosion and melting of the glaciers. Movement followed preexisting discontinuities in the rock. A survey course approximately 2.4 km (1.5 mi) long has been placed across .the fractured ridge. It will be monitored periodically to determine whether movement is continuing, and if so, at what rate.

Colorado↗
USGS1966

Tectonic creep in the Hayward fault zone, California

Tectonic creep is slight apparently continuous movement along a fault. Evidence of creep has been noted at several places within the Hayward fault zone--a zone trending northwestward near the western front of the hills bordering the east side of San Francisco Bay. D. H. Radbruch of the Geological Survey and B. J. Lennert, consulting engineer, confirmed a reported cracking of a culvert under the University of California stadium. F. B. Blanchard and C. L. Laverty of the East Bay Municipal Utility District of Oakland studied cracks in the Claremont water tunnel in Berkeley. M. G. Bonilla of the Geological Survey noted deformation of railroad tracks in the Niles district of Fremont. Six sets of tracks have been bent and shifted. L. S. Cluff of Woodward-Clyde-Sherard and Associates and K. V. Steinbrugge of the Pacific Fire Rating Bureau noted that the concrete walls of a warehouse in the Irvington district of Fremont have been bent and broken, and the columns forced out of line. All the deformations noted have been right lateral and range from about 2 inches in the Claremont tunnel to about 8 inches on the railroad tracks. Tectonic creep almost certainly will continue to damage buildings, tunnels, and other structures that cross the narrow bands of active movement within the Hayward fault zone.

Circular↗