Borehole Geophysical Logging of Water-Supply Wells in the Piedmont, Blue Ridge, and Valley and Ridge, Georgia

The Maastrichtian-Danian boundary surface has been mapped by geophysical logging of water supply borewells in the coastal area of Koge Bugt south of København. The transition from bryozoan limestone of Danian (earliest Palaeogene) age with a variable apparent resistivity between 100 and 250 Ohmm to chalk of Maastrichtian (latest Cretaceous) age with a relatively stable apparent resistivity in the range 60-80 Ohmm is easily detected on most resistivity logs. Gamma logs show a characteristic anomaly with two peaks in the uppermost Maastrichtian chalk approximately 8-10 meters below the Maastrichtian-Danian boundary. This gamma anomaly is caused by a layer of marl, which is found persistently in the whole area between Kobenhavn and Koge. The marl is probably equivalent to the Kj~lby Gaard Marl, known from outcrops of uppermost Maastrichtian chalk in northwest Jylland. A preliminary contour map has been prepared displaying the elevation of the boundary surface between the Danian limestone and Maastrichtian chalk below. This map shows that the limestones are weakly folded with structures very similar to those observed in the outcrops of Stevns Klint and also detected by recent seismic studies of the limestone basement in 0resund. The structures can be interpreted without introducing major vertical displacements along faults.

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FM RADIO SIGNAL STRENGTH MODELING AND PREDICTION IN BLUE RIDGE AND VALLEY & RIDGE PHYSIOGRAPHIC PROVINCES, U.S.A

10.1130/abs/2018se-312755 ◽

2018 ◽

Author(s):

Timothy Warren Land ◽

◽

Andrew T. Joyner ◽

A. Nandi ◽

Michael J. Whitelaw

Keyword(s):

Radio Signal ◽

Signal Strength ◽

Blue Ridge ◽

Modeling And Prediction ◽

Fm Radio ◽

Strength Modeling ◽

Ridge And Valley

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Factors controlling the major ion chemistry of streams in the blue ridge and valley and ridge physiographic provinces of Virginia and Maryland

Hydrological Processes ◽

10.1002/hyp.3360060108 ◽

1992 ◽

Vol 6 (1) ◽

pp. 79-97 ◽

Cited By ~ 30

Author(s):

Larry J. Puckett ◽

Owen P. Bricker

Keyword(s):

Blue Ridge ◽

Ion Chemistry ◽

Major Ion Chemistry ◽

Major Ion ◽

Ridge And Valley

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Enumeration and Identification of Asbestos Fibres in Water

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005264x ◽

1974 ◽

Vol 32 ◽

pp. 526-527 ◽

Cited By ~ 1

Author(s):

O. Mudroch ◽

J. R. Kramer

Keyword(s):

Water Supply ◽

Water Samples ◽

Drainage Basin ◽

Lake Superior ◽

Research Work ◽

List Type ◽

The West ◽

Asbestos Fibre ◽

Amphibole Asbestos

Approximately 60,000 tons per day of waste from taconite mining, tailing, are added to the west arm of Lake Superior at Silver Bay. Tailings contain nearly the same amount of quartz and amphibole asbestos, cummingtonite and actinolite in fibrous form. Cummingtonite fibres from 0.01μm in length have been found in the water supply for Minnesota municipalities.The purpose of the research work was to develop a method for asbestos fibre counts and identification in water and apply it for the enumeration of fibres in water samples collected(a) at various stations in Lake Superior at two depth: lm and at the bottom.(b) from various rivers in Lake Superior Drainage Basin.

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Bacterial biofilm behavior in water-supply lines of dental units

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124811 ◽

1992 ◽

Vol 50 (1) ◽

pp. 882-883

Author(s):

B.D. Tall ◽

K.S. George ◽

R. T. Gray ◽

H.N. Williams

Keyword(s):

Water Supply ◽

Medical Devices ◽

Biofilm Formation ◽

Bacterial Biofilm

Studies of bacterial behavior in many environments have shown that most organisms attach to surfaces, forming communities of microcolonies called biofilms. In contaminated medical devices, biofilms may serve both as reservoirs and as inocula for the initiation of infections. Recently, there has been much concern about the potential of dental units to transmit infections. Because the mechanisms of biofilm formation are ill-defined, we investigated the behavior and formation of a biofilm associated with tubing leading to the water syringe of a dental unit over a period of 1 month.

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