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Aeromagnetic discovery of a Baltimore Gneiss dome in the Piedmont of northwestern Delaware and southeastern Pennsylvania

Michael W. Higgins·George Wescott Fisher·Isidore Zietz
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Abstract

In the central Appalachian Piedmont the “basement complex” is an assemblage of 1,100- to 1,300-m.y.-old gneisses, migmatites, and amphibolites that crops out in “domes” mantled by younger meta-sedimentary rocks of the Glenarm Series. Aeromagnetic data and reconnaissance field work indicate that a previously unknown Baltimore Gneiss dome, here called the Mill Creek dome, is present in southeastern Pennsylvania and northwestern Delaware. The discovery of previously unknown domes of Baltimore Gneiss has bearing on the thickness, structure, and regional relations of the Glenarm Series.

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GeologyArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 39.663420168019655° to 39.95443981287775° latitude; -75.81962861887982° to -75.40634625991062° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Michael W. Higgins, George Wescott Fisher, Isidore Zietz. 1973. Aeromagnetic discovery of a Baltimore Gneiss dome in the Piedmont of northwestern Delaware and southeastern Pennsylvania. https://doi.org/10.1130/0091-7613(1973)1%3C41%3Aadoabg%3E2.0.co%3B2

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