Eastport quadrangle notebook #2, 1907
Page 36
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Transcription
food and a ball is exposed immedi- ately under, the slate; the upper surface striking N. 48° W. and dipping 32° & 50° N. 42° E. A speci- men is 1139. After a covered dip of slate and 25 feet the same kind of staff reappears to the west in a compact mass which shows no cracking planes and which ex- tends for 70 ft. I compute thickness at 32° dip, and add 10 feet for light of exposure. A specimen at 1140. In place the material is rough, blue in patches; blocks light creamy brown. Foot trace of bedding is des- cernible. There massive trachyolite against a mass of very coarse gabbro—1141—which is exposed in large concretionary nodules one foot to two feet thick with an even, snow rounded mass, 4 feet thick. This gabbro resembles a dark granite. The feldspar is well developed purple.—The width of outcrop is about 50 feet. The gabbro appears to be a sill with general inclination similar to the lying sediments. About 20 feet of the massive entirely unbedded triff or volcanic ash seems to lie west of the gabbro similar to that to the east. A specimen is 1142. Fragments over an inch or 2 nearly 3 inches, are exceedingly num- erous. After a covered interval of 15 feet made through some stratified gray flags and thin volcanic ash seems striking N. 35° W. and dipping 40°, N. 55° E. The rock is grayish above but becomes purplish below. The ash seams are usually half an inch or less, the flags to 2-6 inches, one ash seam runs the middle is a foot thick and rather purpl- ish—1143. This series must be about 20 feet thick. It overlies some massive entirely unbedded ash 1144, which is about 20 feet thick and this overlies a very dark purple rhyolite glass unbedded massive possibly a tuya—last grades upward into the ash—1144. A specimen is 1145. Its pigmentary between Selmon as East and Long Cove is composed of black cones of gabbro which is very coarse and ark across some volcanic tuffs. These tuffs are generally purplish color and with purplish ash fragments, some with similar in general way to those near Head of Blackford. These tuffs are massive & without any stratification planes. Very 20 feet thick is very fine glass below to column- lar purplish rhyolite which is underlying & an irregular mass of volcanic mud exposed west the top two mark 184. The east slope of Long Cove. This volcanoes must be much smaller by a few miles (5 or 6) of volcanic tuffs.