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Sharon F. Diehl

Publications and source records attributed to Sharon F. Diehl.

22 records · Page 2Linked to original sources
USGS2004

Surficial geologic map of the southwest Memphis Quadrangle, Shelby County, Tennessee, and Crittenden County, Arkansas

This map is one of seven 1:24,000-scale (7.5-minute) quadrangle maps of the surficial geology of the Memphis, Tennessee, area--part of a series of urban hazard maps. Wind-deposited silt and clayey silt (loess) is the predominant surficial deposit in this quadrangle. The loess was deposited as dust during the last major continental glaciation of the region and it covers the upland to depths of 4.5-16 m. River alluvium (unit Qal), which is chiefly a sandy and gravelly sand deposit about 30 m thick, underlies the Mississippi River floodplain. This unit supports extensive artificial fill and infrastructure used for shipping storage and petroleum processing and storage. Based on paleoliquefaction structures (sand boils) documented in Mississippi River alluvium elsewhere, this unit probably has the potential to liquefy during strong earthquake shaking. No paleoliquefaction structures were observed within the Southwest Memphis quadrangle. Another deposit in the quadrangle is silty alluvium of the Nonconnah Creek floodplain, and is 1-10 m thick. Sparse, unconsolidated pebbly sand deposits are 0.5-3 m thick and make up point bars and channel deposits of Nonconnah Creek.

Scientific Investigations Map↗
USGS1978

Reconnaissance geotechnical study of the Lucerne Granite, Maine

Physical properties, including density and strength, of the Lucerne Granite (Wing, 1958) vary because of inhomogeneities caused by fracturing and differences in texture. Two granitic facies were found: a coarse-grained variety in the southern part of the body and near the edges of the pluton and a medium-grained porphyritic variety in the central and northern sections. Point-load strength tests indicate that the medium-grained porphyritic granite is stronger than the coarse-grained porphyritic or non-porphyritic granite. Results of bulk and grain density tests suggest that rock strength in the weaker granite samples is controlled by microfractures. In the pluton, joint trends changed from a scattered pattern in the north to a preferred orientation in the south. Because it has a simple joint pattern and is homogeneous in texture, the southern part of the Lucerne Granite is a more suitable area for excavation and fluid storage than the northern section.

Maine↗
USGS1977

Preliminary analysis of lineaments and engineering properties of bedrock, Penobscot Bay area, Maine

A remote sensing study of coastal and near coastal Maine was undertaken to identify bedrock features of possible importance to construction. Major lineaments were identified that separate the region into four distinct terrains. Within each terrain, smaller lineaments and other physiographic features show distinctive and consistent patterns, reflecting similarities in bedrock lithology and structure. The major linear features are given the following provisional geographic names: I. Lewiston line 2. Merrymeeting lineament 3. Dover-Foxcroft line 4. Orland lineament 5. Union lineament These linear or curvilinear trends are caused by lithologic contrasts, joints, faults, or foliation in the middle and lower Paleozoic phyllites, schists, gneisses, and granite intrusives. Initial field and laboratory results from a pilot study of bedrock engineering conditions indicate that variations in rock strength and fracture spacing are controlled by lithology, intensity of structural deformation, and alteration. At several locations in the study area faults and major joints are alined with a major lineament. Strength anisotropy ratios are as high as 10 in the foliated rocks but near 1 in the granites. The higher compressive strength direction commonly is perpendicular to foliation and to lineament trends which, in turn, are parallel to faults, major joints, or foliation. Fracture spacing in rocks in the field study area averages 0.5 m for granite and ranges from 0.2 cm to 0.75 m, with an average of 0.15 m, in metamorphic rocks. Diagnostic indications useful for estimating certain construction conditions are shown by point-load and uniaxial compressive strengths. Values for fresh rock range from less than 30 MN/m 2 for weakly bonded phyllite to more than 350 MN/m 2 for dense andesite and metasiltstone. Rock workability is directly related to compressive strength and spacing of joints.

Open-File Report↗