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Research about Maine

Source-linked reports with geographic coverage including Maine.

At least 379 records · Page 21Linked to original sources
USGS1970

Woodcock feeding habits as related to summer field usage in central Maine

In 1968 and 1969, 60 American woodcock ( Philohela minor ) were collected before and after alighting on summer fields in central Maine. A comparison of stomach contents from these birds showed that woodcock fed prior to entering fields at dusk. No evidence was found to indicate that any substantial amount of food was eaten by birds remaining on fields throughout the night. In 1968, the availability and abundance of known woodcock foods were measured in 30 soil samples from one field. Few woodcock foods were found in samples located randomly and at flush sites, thus providing no evidence that birds selected sites where soil invertebrates were concentrated.

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USGS1967

Rocks of eocene age on fippennies ledge, Gulf of Maine

In August 1965, a scallop dredge from R/V Albatross brought up many pieces of fossiliferous opaline chert or porcellanite of Eocene age from Fippennies Ledge , a bank 70 m deep in the central Gulf of Maine . Their presence in this area supports the idea that part of the Gulf is underlain by sedimentary rocks of Tertiary age . Occurrence in the porcellanite of two identifiable species of Bryozoa (ascophoran Cheilostomata), Kleidionella lobata Canu and Bassler and "Ocheto-sella" robusta Canu and Bassler, suggests (1) correlation with the Castle Hayne Limestone of Claiborne to Jackson age ; (2) a temperate zone, distinctly American biogeographic provenance; and (3) accumulation in quiet water.

Maine↗
USGS1967

Geology and petrology of the Greenville quadrangle, Piscataquis and Somerset Counties, Maine

In the Greenville quadrangle, west-central Maine, slate, siltstone, and sandstone (calcareous and noncalcareous) of probable Silurian to Early Devonian age are intruded by a large mafic pluton and two granitic stocks of probable Early Devonian age. Ages of the sedimentary rocks are based upon tentative correlations with fossiliferous beds in adjacent quadrangles because the few fossils in the Greenville quadrangle are nondiagnostic; ages of the intrusive rocks are based upon radiometric age determinations. The sedimentary rocks are tightly folded about northeast-trending axes and have strong slaty cleavage. Widespread graded bedding is very useful in determining the tops of beds and thus the location of fold axes. The sedimentary rocks are in the chlorite zone of metamorphism except in the contact aureoles where the metamorphism ranges from the biotite zone, through the andalusiite-amphibole zone, to the sillimanite-cordierite zone adjacent to the intrusions; retrograde metamorphism is a minor local feature. The mafic rocks are part of the Moxie pluton, which extends southwest and northeast of the Greenville quadrangle for a total distance of about 45 miles. Troctolite and norite are the principal rock types; gabbro is less common. Plagioclase is the dominant mineral; it usually makes up 50-75 percent of the rock. Olivine and orthopyroxene are widespread, clinopyroxene is uncommon and biotite and hornblende are generally present in small amounts. The rocks can be separated into magnesium-rich and iron-rich varieties; magnesium-rich olivine and orthopyroxene are usually accompanied by plagioclase containing from 57 to 77 percent anorthite, and iron-rich olivine and orthopyroxene are associated with plagioclase containing about 50-62 percent anorithite. Compositional layering is rare, but flow structure is very common. Flow structure generally dips northward to eastward, whereas geophysical data indicate that the contacts of the pluton dip southeastward. The granitic stocks are discordant pipelike bodies that range from granodiorite to quartz monzonite in composition. Both the mafic and the felsic intrusions are undeformed and unmetamorphosed. Slate quarrying was once an important industry in the region, but in 1965 only one quarry was active at Monson just east of the report area. Slate is a potential source of raw material for lightweight concrete aggregate. There are several possible sites for stone quarries in the intrusive masses. Sand and gravel resources seem to be limited. Small amounts of sulfides that have low copper and nickel values are known at a few places in the mafic pluton.

Maine↗
USGS1967

Geology of the Arnold Pond quadrangle, Oxford and Franklin Counties, Maine

The Arnold Pond quadrangle lies on the northwest limb of the boundary Mountain anticlinorium (Albee, 1961), a major northeast-trending fold that extends across northern New Hampshire, west-central Maine and adjacent Quebec. The anticlinorium is defined in a regional sense by the Taconic unconformity separating pre-Silurian rocks from the rocks of Silurian and Devonian age. In the western part of the Arnold Pond quadrangle this unconformity is folded and locally faulted. Within the anticlinorium is a thick and highly folded sequence of green salte and quartzite, black slate, mafic and felsic volcanic rocks, and graywacke dated in part as late Middle Ordovician (Harwood and berry, 1967). These pre-Silurian rocks are flanked to the northwest by calcareous slate and limestone, thin lenses of conglomerate, and well-bedded slate and quartzite of Late Silurian to Early Devonian Age. Because the complete section of rocks in the anticlinorium is not exposed in the Arnold Pond quadrangle, the interested reader is referred to the work of Hatch (1963) and Green (1964; in press) in northern New Hampshire; Albee and Boudette (in press), Boucot and others, (1964), Harwood (1966), and Harwood and Sealy, (1967) in west-central Maine; and Marleau (1957; 1959) in adjacent Quebec.

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