Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Engineering Geology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
USGS2019

Seismological, geological, and geotechnical engineering aspects of the 2018 MW 6.6 Hokkaido Eastern Iburi earthquake

The 2018 Hokkaido Eastern Iburi MW6.6 earthquake struck the southern coast of the north island of Japan in the early morning (3:08 AM JST) on September 6, 2018. The event had a hypocentral depth of 35 km, centered beneath the port city of Tomakomai. Extremely strong shaking with peak ground acceleration in excess of 0.5 g was felt in the communities directly north of Tomakomai, in the districts of Abira and Atsuma. There, a very high density of landslides occurred in pumices soil that affected the majority of slopes in the region above the floodplain. These landslides were typically a thin veneer of 1 to 3 m of recent (<9000 ybp) volcanic pumice mantling older Kawabata marine sedimentary rocks. The source of the pumice layers are recent eruptions from Mt. Tarumae, south of Shikotsu-ko Caldera lake. Several block megaslides were observed in the Kawabata marine unit. A flow failure resulting from soil collapse or liquefaction was observed in fill deposits placed in a residential community district of Kiyota ward in Sapporo. The community, Satozuka-1 is situated on a natural steep ravine that was filled with pumice soil to level construction area to a gently sloping landscape for housing construction. The flow failure consisted of lateral migration of soil from the upper slope regions of the community onto the surface of the lower community. The upper community topographically deflated as large quantities of fluidized soil flooded the lower streets.

Hokkaido↗
USGS2025

A synthesis engine for constructing geologic maps of the United States

The geologic history of the United States is cataloged in thousands of geologic maps produced during many decades. However, the disparate nature of these individual maps makes it challenging to assess resources, research geologic histories, or characterize natural hazards holistically across the Nation. The U.S. House of Representatives 2020 appropriations bill for the U.S. Department of the Interior (H.R. 116-100) requires the U.S. Geological Survey to “bring together detailed national and continental-resolution [two-dimensional] and [three-dimensional] information produced throughout the Survey and by [F]ederal and [S]tate partners.” In response to this directive, this report presents a compilation and synthesis of geologic maps across the United States in the form of a relational database. The synthesis database includes thematic maps that synthesize the Nation’s geology, and retains the original input maps as well as linkages to standardized vocabularies to aid the discoverability of geologic information. Specifically, the synthesis database is targeted toward producing four National-resolution maps for the conterminous United States: Quaternary geology, the geology at the Earth’s surface, pre-Quaternary geology, and Precambrian geology. In addition, the synthesis database includes the infrastructure necessary to expand to additional resolutions in the future.

conterminous United States↗
USGS1974

Geologic map and engineering data for the Highlands Ranch Quadrangle, Arapahoe and Douglas counties, Colorado

The map and accompanying tables are designed to be of use to scientists and nonscientists alike. Physical characteristics of the bedrock units and surficial units are described in table 1 (sheet 2) and table 2 (sheet 3), respectively. Those deposits that are known to be less than 5 feet (<2 m) thick are not mapped or described. Residuum and weathered and unweathered bedrock are not differentiated on the map.

Colorado↗
USGS1973

Measurement of lateral erosion at proposed river crossing sites of the Alaskan pipeline

This study of lateral erosion rates by comparison of aerial photographs was undertaken at the request of D. M. Culbertson, hydraulic engineer, U.S. Geological Survey, Menlo Park, Calif., and preparatory work in Alaska (during June 1-18, 1971) was done with the cooperation of Harry Hulsing, district chief, Alaska District. Examination of river crossings between the Yukon River and Prudhoe Bay was done by helicopter, for the use of which I am indebted to Giles McDonald of the Bureau of Land Management. Most of the crossing sites described here were examined in the field, in too brief a time to permit quantitative measurements but long enough to be of much assistance in interpretation of the aerial photographs. Location of the earlier photographs with reference to the terrane was difficult because of the inaccuracy of existing index sheets, but it was greatly facilitated by Ray Krieg of the R & M Engineering Geological Consultants in Fairbanks and by personnel of the Alyeska Pipeline System Office in Anchorage. This report was prepared at Washington University in St. Louis, Mo., with support by Research Grant 8623-EN, Airphoto interpretation of the form and behavior of alluvial rivers, from the U.S. Army Research Office in Durham, N. C.

Alaska↗
USGS1952

Floods of 1950 in the Red River of the North and Winnipeg River basins

The floods of April-July 1950 in the Red River of the North and Winnipeg River Basins were the largest that have occurred in several decades and caused the greatest damage that the flooded area has ever sustained. Five lives were lost in the United States, owing to causes directly connected with the floods. The dual peaks--on upper river and tributaries, one in April and the other in May--of nearly the same size and" the large lake-like body of flood-water ponded between Grand Forks and Winnipeg were notable features of the flood in the Red River of the North Basin. The flood in the Winnipeg River Basin was characterized by the unusually large volume of runoff and the lateness of cresting on the Lake of the Woods. The floods were caused by a combination of causes: high antecedent soil moisture, high antecedent runoff, heavy snowfall, delayed breakup, and heavy precipitation during breakup. Mid-March snow-surveys, made in the area by hydrographers of the United States and Canadian services, showed that the snow pack north of Fargo, N. Dak., had an unusually high water content and a runoff potential increasing from west to east. A narrow band, extending from near Grand Forks, N. Dak., east-northeastward across the basin, had a water content of 5 inches or higher. April 15 marked the beginning of rapid melting throughout the basins; most of the snow was turned into water by the end of the first melt period on April 24. A return of winter-like conditions until May 10 brought more snow and set the stage for second flood crests. The records of stage and discharge collected on the Red River of the North at Grand Forks, N. Dak., since 1882 show that the important 1897 flood slightly exceeded the 1950 flood in both stage and discharge. Records collected by the Geological Survey and Corps of Engineers on the Red River of the North show that the 1950 flood stages exceeded any previously known from just below the mouth of Turtle River to the international boundary. Records for streams tributary to the Red River of the North between Fargo and the Roseau River show, in general, that the 1950 flood events exceeded those of any known past floods. In the storage basins of the Winnipeg River, Lake of the Woods and Rainy Lake reached a stage comparable to that of 1916; and the Winnipeg River discharge at Slave Falls exceeded the highest previously recorded, maximum, which occurred in 1927. Records of floods on the Red River at Winnipeg show that the 1950 flood did not reach as high a stage as those of 1826, 1852, and 1861. The total tabulated damage to Winnipeg, the largest urban center in the area reported on, was about $20,000,000 in the city, and $12,000,000 in surrounding suburbs. The fight against flooding in Greater Winnipeg began on April 21 in the area adjacent to the municipal hospitals and was considered ended with the reopening of Norwood Bridge on June 1. About 80, 000 people were evacuated from their homes in Greater Winnipeg during the flood, and plans were ready to evacuate a greater number had the water risen higher. This report contains records of stage and discharge for the flood period at 70 stream-gaging stations, 21 records of mean daily discharge at stream-gaging stations, 11 records of stage at river-height gages, and 7 records of storage or elevation of reservoirs or lakes. A summary table shows crest stages and discharges at 129 points for the 1950 event compared with the highest known past stages and discharges. Also included is a discussion of concurrent meteorology and of past floods on main streams and tributaries.

Water Supply Paper↗
USGS1970

Methods and applications of electrical simulation in ground-water studies in the lower Arkansas and Verdigris River Valleys, Arkansas and Oklahoma

The Arkansas River Multiple-Purpose Plan will provide year-round navigation on the Arkansas River from near its mouth to Muskogee, Okla., and on the Verdigris River from Muskogee to Catoosa, Okla. The altered regimen in the Arkansas and Verdigris Rivers will affect ground-water conditions in the adjacent alluvial aquifers. In 1957 the U.S. Geological Survey and U.S. Army Corps of Engineers entered into a cooperative agreement for a comprehensive ground-water study of the lower Arkansas and Verdigris River valleys. At the request of the Corps of Engineers, the Geological Survey agreed to provide (1) basic ground-water data before, during, and after construction of the Multiple-Purpose Plan and (2) interpretation and projections of postconstruction ground-water conditions. The data collected were used by the Corps of Engineers in preliminary foundation and excavation estimates and by the Geological Survey as the basis for defining the hydrologic properties of, and the ground-water conditions in, the aquifer. The projections of postconstruction ground-water conditions were used by the Corps of Engineers in the planning, design, construction, and operation of the Multiple-Purpose Plan. Analysis and projections of ground-water conditions were made by use of electrical analog models. These models use the analogy between the flow of electricity in a resistance-capacitance circuit and the flow of a liquid in a porous and permeable medium. Verification provides a test of the validity of the analog to perform as the aquifer would, within the range of historic forces. The verification process consists of simulating the action of historic forces which have acted upon the aquifer and of duplicating the aquifer response with the analog. The areal distribution of accretion can be treated as an unknown and can be determined by analog simulation of the piezometric surface in an aquifer. Comparison of accretion with depth to piezometric surface below land surface shows that accretion decreases with decreasing depth to water level. The decrease in accretion is attributed mostly to the increase in evapotranspiration from the aquifer, and where water levels are very near the land surface, to the rejection of recharge. The maximum accretion and the decrease in accretion with the decrease in depth to water are dependent upon the climate and the thickness and lithology of the fine-grained material overlying the aquifer. Dams on the Arkansas and Verdigris Rivers will impose a direct change in water levels in the aquifers adjacent to the rivers. This change will be attenuated by the resultant change in accretion to the aquifer. The analogs of aquifers in the valleys were used to determine the change in ground-water level from preconstruction to postconstruction conditions.

Water Supply Paper↗