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Research about Maine

Source-linked reports with geographic coverage including Maine.

At least 397 records · Page 22Linked to original sources
USGS1964

Heavy metals in stream sediment, west-central Maine

This map presents the initial results of a geochemical reconnaissance of stream sediment in west-central Maine. The area covered by this map corresponds approximately to the area covered by sheets 2 and 4 of the geologic and aeromagnetic map of northern Maine (Boucot and others, 1960).

Maine↗
USGS1964

Reconnaissance bedrock geology of the Wabassus Lake quadrangle, Washington County, Maine

Generally, shear zones in quadrangles of this area parallel the faults, especially those trending northeasterly. Additional faults and shear zones doubtless present in Wabassus Lake quadrangle but not shown for lack of field work in some areas, and lack of outcrops in others. Some lineaments seen on areal photographs, but not field checked, might be faults.

Maine↗
USGS1964

Suggested exploration target in west-central Maine

Reconnaissance geochemical drainage surveys have located a stream in the southern part of the Long Pond quadrangle in Somerset County, Maine, where the active stream sediment contains as much as 2,500 parts per million (ppm) lead and 7,000 ppm zinc. Although this anomaly has been known for some time, its apparent significance has recently increased. Reappraisal of the anomalous pattern in the light of a large quantity of geochemical data obtained by a regional geochemical mapping program during the past two years has shown that this lead anomaly is by far the strongest one yet found by the Geological Survey in Maine. Galena-and pyrite-bearing quartz veins are present in the drainage basin of this stream, but the exposed veins are not believed to contain enough lead to be the principal cause of the geochemical anomaly. Accordingly, the drainage basin of this stream is believed to be above average in mineral potential. The anomalous stream, here named Pyrite Creek for convenience, is the northeastern branch of a major tributary to Bean Brook. Figure 1 presents the data of the detailed geochemical survey along Pyrite Creek, reconnaissance geochemical data in the surrounding area, and the approximate distribution of the major rock types.

Maine↗
USGS1963

The peg claims spodumene pegmatites, Maine

The Peg Claims pegmatites are located southwest of Rockland in the towns of Warren and Cushing, Knox County, Maine . These pegmatites are representative of a group of zoned, granitic, lithium-bearing pegmatites in which spodumene is present nearly from wall to wall. The pegmatites are discordant, steeply dipping, tabular bodies in the Penobscot quartz-mica schist near the Waldoboro granite. A narrow quartz-tourmaline-muscovite-apatite aureole is commonly developed around each of the pegmatites and around inclusions of country rock in the pegmatites . The pegmatites are zoned, and each may be subdivided into: (1) a narrow quartz-muscovite border zone; (2) a narrow albite-quartz-muscovite wall zone; (3) and an albite-quartz- spodumene -perthite core that constitutes most of the pegmatite . Cross-cutting, fine-grained, quartz-albite- spodumene -muscovite lenses are found within pegmatite cores. The bulk mineralogy and variations in the mineralogy from zone to zone of the largest body (Dike 1) were determined by megascopic mineral point-counts. There is a decrease of albite, quartz, and muscovite and an increase of spodumene and perthite from the border and wall zones into the core. The alkali contents of Dike 1 and of each of its zones were determined by flame photometer and X-ray fluorescence analyses. The amount of Na20 decreases and the amounts of K 2 O, Li 2 0, Rb 2 0, and CS 2 O increase from the border and wall zones into the core. Estimated bulk compositions of Dike 1 and of each of its zones were computed. It is concluded that the distribution, structural features, bulk chemistry, and the mineralogical, chemical, and textural zoning of the pegmatites are consistent with development by fractional crystallization of a pegma-titic fluid in a restricted system.

Maine↗