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Martin Francis Kane

Publications and source records attributed to Martin Francis Kane.

12 recordsLinked to original sources
USGS1983

Aeromagnetic map of Yucca Mountain and surrounding regions, southwest Nevada

Magnetic anomalies over Yucca Mountain and surrounding areas are largely caused by variations in magnetic properties and shapes, including structural offsets, of the extensive volcanic units that underlie the region. In a few places the anomalies are caused by intrusions. Correlation between magnetic properties measured from rock samples and those derived from rock unit-magnetic anomaly associations is excellent. Anomaly characteristics, extensive magnetic gradients, and marked changes in the regional magnetic field can be coupled with the magnetic properties of the rock units to delineate structural boundaries. Three major boundaries are indicated by contrasts in regional magnetic expressions. Less extensive but more clearly indicated boundaries in the immediate vicinity of Yucca Mountain are interpreted from a distinctive pairing of northerly-trending linear positive and negative anomalies which are caused by vertical displacement in generally gently dipping volcanic beds. The displacement between beds is located approximately along the border line between the linear anomaly pairs. One series of pairs of more northeasterly trend lies over the general location of a change from moderately thick to very thick volcanic units that was interpreted from gravity data. Several low amplitude but distinctively shaped anomalies in areas underlain primarily by sedimentary strata indicate the presence of intrusions and faults.

Open-File Report↗
USGS1977

Correlation of major eastern earthquake centers with mafic/ultramafic basement masses

Extensive gravity highs and associated magnetic anomalies are present in or near seven major eastern North American earthquake areas as defined by Hadley and Devine (1974). The seven include the five largest of the eastern North American earthquake .centers. The immediate localities of the gravity anomalies are, however, relatively free of seismicity, particularly the largest events. The anomalies are presumably caused by extensive mafic or ultramafic masses embedded in the crystalline basement. Laboratory experiments show that serpentinized gabbro and dunite fail under stress in a creep mode rather than in a stick-slip mode. A possible explanation of the correlation between the earthquake patterns and the anomalies is that the mafic/ultramafic masses are serpentinized and can only sustain low stress fields thereby acting to concentrate regional stress outside their boundaries. The proposed model is analogous to the hole-in-plate problem of mechanics whereby stresses around a hole in a stressed plate may. reach values several times the average.

Open-File Report↗
USGS1963

Exploratory geophysical traverses in the Oakfield Hills area, Smyrna Mills Quadrangle, Maine

Ground magnetic, gravity, and electromagnetic measurements in the Oakfield Hills area have delineated a series of steeply dipping, dikelike rock units with high apparent susceptibility, high density, and often high conductivity. The measurements were made to investigate the source of a 3000-gamma aeromagnetic anomaly. The rock units are apparently a series of lenticular beds of manganese-bearing iron formation which have been thermally metamorphosed by a nearby intrusion. Some of the electromagnetic anomalies are probably caused by the presence of sulfides.

Maine↗