USGS Visual Identifier

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GEOLEX database

Geologic Unit: Moat

Publication:
Billings, M.P., 1928, The petrology of the North Conway quadrangle 
   in the White Mountains of New Hampshire: American Academy of 
   Arts and Sciences Proceedings, v. 63, no. 3, p. 67-137.
Usage in Publication:
Moat volcanics

Modifications: Geologic Province: Dominant Lithology:
 Named
 New England province
 Breccia
 Tuff
 Porphyry

Summary:
Named for South Moat Mountain. Includes rocks previously mapped as Pequawket breccia and quartz porphyry by Hitchcock (1877). Occurs in North Conway 15-min quad on Moat Mountain and on Mount Kearsarge. Consists of siliceous volcanic flow rocks and interbedded tuffs and breccias. Section at Red Ridge is 8,300 ft; section on northwest slope of Big Attitash toward Humphrey Ledge is 9,700 ft; entire thickness estimated at 11,800 ft. Forms a simple monocline, the bottom and top having been stripped away. Intruded by Albany and Conway granites. Contains fragments of Montalban schist, Intervale clay-slate, Chatham granite, and Meredith porphyritic granite. No age given.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Billings, M.P., 1956, The geology of New Hampshire; Part II, 
   Bedrock Geology: New Hampshire State Planning and Development 
   Commission, 203 p.
Usage in Publication:
Moat volcanics

Modifications: Geologic Province: Dominant Lithology:
 Areal limits
 Age modified
 Overview
 New England province
 Rhyolite
 Andesite
 Basalt
 Tuff

Summary:
Moat volcanics present on Moat Mountain, on Mount Pequawket, in the Ossipee Mountains, in the southern Belknap Mountains, on Mount Hale, on North Twin Mountain, and 3 mi southeast of Mount Lafayette summit. Consists of rhyolite, andesite, basalt, flows, tuffs, breccias. Rhyolite flows are light-gray, blue-gray, and red porphyries with quartz and feldspar phenocrysts. Age is Mississippian based on stratigraphic position and is part of White Mountain plutonic-volcanic series which is younger than Early Devonian Littleton Formation. Moat is probably same age as Quincy granite and related rocks in MA which are pre-Pennsylvanian. Recent radioactive age determinations support this age.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Hatch, N.L., Jr., and Moench, R.H., 1984, Bedrock geologic map 
   of the wilderness and roadless areas of the White Mountain 
   National Forest, Coos, Carroll, and Grafton Counties, New 
   Hampshire: U.S. Geological Survey Miscellaneous Field Studies 
   Map, MF-1594-A, 1 sheet, scale 1:125,000
Usage in Publication:
Moat Volcanics*

Modifications: Geologic Province: Dominant Lithology:
 Age modified
 New England province
 

Summary:
Although ages as old as Late Triassic have been reported from rocks of the White Mountain Plutonic-Volcanic Suite in southwestern ME, no ages other than Early Jurassic have been reported from this map area.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Moench, R.H., Canney, F.C., and Gazdik, G.C., 1984, Mineral 
   resource potential map of the wilderness and roadless areas 
   of the White Mountain National Forest, Coos, Grafton, and 
   Carroll Counties, New Hampshire: U.S. Geological Survey 
   Miscellaneous Field Studies Map, MF-1594-B, 12 p., 1 sheet, 
   scale 1:125,000
Usage in Publication:
Moat Volcanics*

Modifications: Geologic Province: Dominant Lithology:
 Age modified
 New England province
 

Summary:
The White Mountain batholith and outlying bodies, including the Moat Volcanics, are Jurassic in age.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Eby, G.N., Krueger, H.W., and Creasy, J.W., 1992, Geology, 
   geochronology, and geochemistry of the White Mountain batholith, 
   New Hampshire, IN Puffer, J.H., and Ragland, P.C., eds., 
   Eastern North American Mesozoic magmatism: Geological Society 
   of America Special Paper, 268, p. 379-397.
Usage in Publication:
Moat volcanics

Modifications: Geologic Province: Dominant Lithology:
 Isotopic dating
 New England province
 

Summary:
Lower part of Moat volcanics dated at 173.1+/-1.5 Ma using Rb/Sr whole-rock methods. Upper part of Moat dated at 168.2+/-1.2 Ma using Rb/Sr whole-rock methods. Trachyte of Moat volcanics dated at 169+/-4 Ma and 162+/-4 Ma using K-Ar whole rock methods.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Moench, R.H., Boone, G.M., Bothner, W.A., Boudette, E.L., Hatch, 
   N.L., Jr., Hussey, A.M., III, Marvinney, R.G., and Aleinikoff, 
   J.N., 1995, Geologic map of the Sherbrooke-Lewiston area, 
   Maine, New Hampshire, and Vermont, United States, and Quebec, 
   Canada: U.S. Geological Survey Miscellaneous Investigations 
   Series Map, I-1898-D, 56 p., 2 sheets, scale 1:250,000, 
   Prepared in cooperation with the Maine Geological Survey and 
   the New Hampshire Geological Survey.
Usage in Publication:
Moat Volcanics*

Modifications: Geologic Province: Dominant Lithology:
 Isotopic dating
 Age modified
 Areal limits
 New England province
 

Summary:
Shown mapped on North and South Moat Mountains, Kearsarge North [a mountain], Mount Lowell, southeast slopes of Mount Hancock, and Mount Tom. Age is Jurassic based on radiometric dates reported in Eby and others (1992) (173.1+/-1.5 Ma Rb/Sr whole-rock isochron on lower part of Moat, 168.2+/-1.2 Ma Rb/Sr whole-rock isochron on upper part of Moat, and 169+/-4 Ma and 162+/-4 Ma K-Ar whole-rock isochron on trachyte from Moat), and using time scale of Harland and others (1989). Report includes geologic map, cross sections, and correlation chart.
Source: GNU records (USGS DDS-6; Reston GNULEX).


Publication:
Lyons, J.B., Bothner, W.A., Moench, R.H., and Thompson, J.B., 
   Jr., 1997, Bedrock geologic map of New Hampshire: U.S. 
   Geological Survey Special Map, 2 sheets, scale 1:250,000 and 
   1:500,000, Prepared in cooperation with the U.S. Department 
   of Energy and State of New Hampshire.  Supersedes U.S. 
   Geological Survey Open-File Report OF-86-1.
Usage in Publication:
Moat Volcanics*

Modifications: Geologic Province: Dominant Lithology:
 Overview
 Age modified
 Isotopic dating
 New England province
 

Summary:
Used as Moat Volcanics of White Mountain Plutonic-Volcanic Suite. Consists of bedded and ignimbritic tuffs, flows, and breccias; includes porphyritic rhyolite, with minor trachyte. Age changed from Early Jurassic to Middle Jurassic(?) based on the following isotope ages: lower part dated at 173+/-2 Ma using Rb/Sr methods (Eby and others, in press), upper part dated at 168+/-1 Ma using Rb/Sr methods (Eby and others, 1992), and trachyte dated at 169+/-4 and 162+/-4 Ma using K-Ar methods (Eby and others, 1992). Report includes geologic map and correlation chart, and 1:500,000-scale map of plutons and sample localities for age dating.
Source: GNU records (USGS DDS-6; Reston GNULEX).