University of California Publications. Bulletin of the Department of Geological Sciences, 2. sējumsUniversity of California Press, 1902 |
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abundant actinolite analcite andesite angle appear augite bands basalt basin beds Berkeley Hills Berkeleyan California Campan Cañon character cherts Chico cliffs coarse Coast Ranges coastal color conglomerate Creek crystalline crystals cutting deposits diabase diallage dikes elevation erosion eruptive evidence extends facies fault feet feldspar feldspathic formation forms fossils fragments Frowning Ridge gabbro Geol geological grains granite gravels Grizzly Peak hornblende hypersthene inches intrusive island Isthmus John Day Knoxville latter lava limestone locality lower magma magnetite mass miles mineral Miocene Monterey Morrito mountain nearly occur olivine Orindan outcrop Panama peneplain peninsula peridotite phenocrysts plain Pleistocene Pliocene Point Sal porphyritic portion present probably pyroxene quartz region rhyolite rocks San Pablo sandstone Santa serpentine shales shore side Siestan silica slopes species specimens strata stream structure subaerial submarine summit surface syncline terraces thickness tion topography tuff upper valley volcanic width
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2. lappuse - Sal does not form a very marked break in the regularity of the coast line, yet it shows several miles of rocky cliffs which offer exceptional exposures for the study of its remarkably • interesting geology. The geographical features of the accompanying map have been taken from the map of Santa Barbara County, the contours having been added with the aid of an aneroid. The area included com prises all that portion of the region about Point Sal which presents any marked geological interest. It is...
293. lappuse - The lower division consists usually of highly-colored shale, which breaks down readily, forming characteristic mud-covered domes. These beds are in the main a deep red, with occasional alternating strata of buff or white ash. At Bridge Creek alternating beds of red, white, and green, occurring in a group of the typical hills of this division, form a striking feature of the landscape, the colored strata making sharply-defined rings about the hills.
85. lappuse - the general succession is from a rock of average composition through less silicious and more silicious ones to rocks extremely low in silica and others extremely high in silica, that is, the series commences with a mean and ends with extremes.
309. lappuse - Kept. US Geol. Surv., p. 446, 1883-84. Povana Bendirei (Ward) Lesq., Proc. US Nat. Mus., vol. xi, p. 16, pi. viii, fig. 4, 1888. "Gravel and tuff section, south side of East Fork Valley. Four miles east of Dayville. [Locality 880.] Carpinus grandis Unger. " The flora of Van Horn ranch [loc. 878] finds its greatest affinity with the Auriferous gravels and allied floras of California and is to be regarded as upper Miocene in age. "The locality four miles east of Dayville [loc. 880] is represented by...
276. lappuse - The typical localities of this Miocene basin are along the John Day River, and this name may very properly be used to designate the lake basin. The strata in this basin are more or less inclined and of great thickness.
277. lappuse - Taxodium nearly resembles that from the shales at Osino, Nevada, and on various grounds I suspect that these beds form a part of the 'Amyzon Group' (American Naturalist, June, 1880), with the shales of Osino and of the South Park of Colorado. Below these, is a system of fine-grained, sometimes shaly, rocks of delicate gray, buff, and greenish colors, containing calamites, which Professor Condon calls the Catamite beds. Their age is undetermined.
276. lappuse - The regions of the John Day River and Blue Mountains furnish sections of the formations of central Oregon. Above the Loup Fork or Upper Miocene there is a lava outflow, which has furnished the materials of a later lacustrine formation, which contains many vegetable remains. The material is coarse, and sometimes gravelly, and it is found on the Columbia River, and I think also in the interior basin. Professor Condon, in his unpublished notes, calls this the Dalles Group.
376. lappuse - From the fact that several of the lava sheets have lateritic surfaces, which indicates a long exposure to weathering, and from the further fact that waterworn gravel is to some extent intercalated with the lavas, it is apparent that there were intervals between the successive flows. During these intervals not only would the surface of the lava be subject to decay under the processes of weathering, but the effects of erosion would be manifest in proportion to the duration of the interval; and if the...
276. lappuse - Vol. 9, p. 52. whole country has since been deeply buried by successive overflows of volcanic rock. It is only where the latter have been washed away that the lake deposits can be examined. The discovery and first explorations in this basin were made by Rev. Thomas Condon, the present state geologist of Oregon. The typical localities of this Miocene basin are along the John Day River, and this name may very properly be used to designate the lake basin.
277. lappuse - These are composed of fine material, and vary in color from a white to a pale brown and reddish-brown. They contain vegetable remains in excellent preservation, and indeterminable fishes. The TtLcodium nearly resembles that from the shales at Osino, Nevada, and on various grounds I suspect that these beds form a part of the Amyzon group (American Naturalist, June, 1880), with the shales of Osino and of the South Park of Colorado.