Heavy-mineral variability in bottom sediments of the lower Chesapeake Bay, Virginia

F. Firek; G. L. Shideler; P. Fleischer

doi:10.1016/0025-3227(77)90020-2

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Heavy-mineral variability in bottom sediments of the lower Chesapeake Bay, Virginia

F. Firek·G. L. Shideler·P. Fleischer

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Abstract

Heavy minerals in bottom-sediment samples of the lower Chesapeake Bay show distribution patterns and interrelationships that denote characteristic mineral suites associated with defined geographic provinces. The Baymouth province has a garnet-hornblende-pyroxene suite, which is largely attributed to the influx of littoral and shelf sediments; the Eastern Shore province has a similar suite, derived largely from coastal erosion of the Eastern Shore peninsula. The Northern and Combined River provinces have a zircon-tourmaline-staurolite assemblage, which reflects derivation from an Appalachian Piedmont-Atlantic Coastal Plain sourceland. The Western Shore province is associated with a zircon-epidote-staurolite assemblage, apparently derived jointly from tributary influx and coastal erosion of the western shore. Factor analysis identified two major factors that account for 63% of the total variation in the relative amounts of the seven most common heavy minerals. The dominant factor (44%) is based on a zircon-hornblende-staurolite-pyroxene relationship, which indicates that mineral stability, as influenced by sediment maturity, is a major contributing factor. The second factor (19%) based on a tourmaline-epidote-staurolite-garnet relationship indicates that provenance is another major cause of heavy-mineral variability within the lower bay.

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Marine Geology Article

Source-reported bounding extent: 36.94229799680893° to 38.3912568748371° latitude; -76.89560298064909° to -75.59913425683538° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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F. Firek, G. L. Shideler, P. Fleischer. 1977. Heavy-mineral variability in bottom sediments of the lower Chesapeake Bay, Virginia. https://doi.org/10.1016/0025-3227(77)90020-2

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