. Annual Reports of the Department of the Interior for the Fiscal Year Ended June 30, 1900--Twenty-First Annual Report of the United States Geological Society. ^ contain some cloudymaterial as inclusions, and f re(iueutly also capilhuy needles of is for the most part very fresh and finely twinned microcline, :^1 GEOL, IT 3—Ul .). —Secondarily enlarged quartz grains in the SouthBritain arkose conglomerate. Magnified about 50diameters. 6-1 NEWARK SYSTEM OF POMPERAUG VALLEY, CONN. with occasional grains of acid plagioclase and untwinncd feldspar. Thecementing material is calc
. Annual Reports of the Department of the Interior for the Fiscal Year Ended June 30, 1900--Twenty-First Annual Report of the United States Geological Society. ^ contain some cloudymaterial as inclusions, and f re(iueutly also capilhuy needles of is for the most part very fresh and finely twinned microcline, :^1 GEOL, IT 3—Ul .). —Secondarily enlarged quartz grains in the SouthBritain arkose conglomerate. Magnified about 50diameters. 6-1 NEWARK SYSTEM OF POMPERAUG VALLEY, CONN. with occasional grains of acid plagioclase and untwinncd feldspar. Thecementing material is calcite, but in comparison with that of the lessintense!} metamorphosed rock it is present in smaller amount and isto a larger extent twinned polysynthetically. In addition to the acces-sor} minerals observed in the specimens, the slide reveals a little ura-litic horn})lende, garnet, black tourmaline, sphene, zircon, and mag-netite. In one instanct^ sphene appeared to surround the garnet in ahalo. It is believed that tlie evidences of strong deformation which arefound in the wavy extinction and in the banding of the quartz grainsin all phases of this rock date from a period when these grains wereconstituents of the crystalline rocks of the region, and hence they are inno way to be connected with the metamorphism of the conglomerate. SECTIO
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Keywords: ., bookauthorunitedst, bookcentury1900, bookdecade1900, bookyear1901
