... in competent, brittle rocks (Precambrian crystalline basement, batholith intrusions, and Elkhorn Mountains Volcanics). Ductile rocks (Mesozoic shales and Belt Supergroup argillites) do not commonly contain major fissure veins, except where these rocks have been contact metamorphosed and have become more...

...Robert A. Houston; John H. Dilles Abstract The Butte district contains two porphyry Cu-Mo deposits and the younger zoned Main stage base metal lode deposits that formed in the period from 66 to 62 Ma, synchronous with Laramide compressional thrust faulting and folding in southwest Montana. New...

... (1993) . Several types of mineral deposits are hosted by the Boulder batholith. Silver-rich polymetallic quartz vein deposits in the Basin and Boulder districts, as well as similar silver-rich veins in the Rimini and Clancy districts to the north ( Knopf, 1913a ) and the Elkhorn district...

... lithologies include limestone, sandstone, and conglomerate ( Oetking et al., 1967 ). Several mining districts lie within the study area, including the Globe-Miami, Superior, and the Ray copper mining districts ( Gambell, 1978 ), the Mineral Hill gold and silver mineral deposit, and several small...

... Mineralization of Late Cenozoic Era In The Sapporo-Iwanai District. Y asushi W atanabe . Miscellaneous Map Series 38. 1:200,000. English and Japanese, printed on both sides, 2001. Price: F\3,600. Prof. Paper 1624. Migration of the Acadian Orogen anad Foreland Basin Across the Northern Appalachians...

... to obliterate the break; the subsidence amounts to as much as fifteen meters. It is diffi- cult to doubt the relationship between the phenomena." 7. Lindgren in his report on the Blue Mountains* called atten- tion years ago to a fault scarp along the front of the Elkhorn Moun- tains near Baker. This is a very...

... approximately 12,500 square miles of west-central Montana. From an an extensive questionnaire canvass, a maximum intensity of V was reported from a few places, principally from the Maudlow area, extending northwest through Radersburg to Elkhorn. At a ranch in the Maudlow area (close to 46.0 ° north, 111°06...

..., Maysville, and Richmond Groups, and the Mount Hope, Fairmount, Bellevue, Corryville, Mount Auburn, Arnheim, Waynesville, and Liberty Formations. Economy, Southgate, and McMicken have been suppressed at their type areas by Weiss and others (1965), and the name Elkhorn Formation recently has been suppressed...

... oppositely directed wedges, the Saluda thinning northward, the Whitewater thinning southward and overriding the Saluda.” Of the “formations” named, only the Saluda appears to satisfy the modern definition of a lithostratigraphic unit. The Elkhorn formation was named by Cumings (1908 , p. 678...

... recovered from sites along Elkhorn Creek, which is in the un-glaciated corridor mentioned above (Figure 1 ). However, we have not yet confirmed an outcrop in or near this corridor, which was modified during the Holocene, especially after European settlement. Therefore we assume that the Sterling pipestone...

... in the Elkhorn district, Montana . Econ. Geol . 79 , 573 – 579 . Wolf M.B. London D. ( 1997 ): Boron in granitic magmas: stability of tourmaline in equilibrium with biotite and cordierite . Contrib. Mineral. Petrol . 130 , 12 . Wood S.A. Williams-Jones A.E. ( 1993...

... poles selected to represent the cratonic paleomagnetic field in the studies of ( a ) Besse and Courtillot (2002) , ( b ) Torsvik et al. (2008) , and ( c ) Enkin (2006) and Kent and Irving (2010) . AM, Adel Mountains pole; EM, Elkhorn Mountain pole; ML, Maudlow Formation pole; BB, Boulder...

... , Hoboken, NJ . Trinkle , E.J. and Hower , J.C. 1984 . Petrography of the middle Pennsylvanian Upper Elkhorn no. 3 coal of eastern Kentucky, USA . International Association of Sedimentologists, Special Publication , 7 , 349 – 360 . Ward , C.R. 1984 . Coal Geology and Coal...

... the Midland and Val Verde basins and contains such productive pre-Permian structural highs as Todd, Elkhorn, and Midway Lane. The Val Verde basin, at the south, is a deep relatively unexplored basin which is terminated abruptly on the southern side by Llanoria and the associated Marathon folded and overthrust...

...) . REFERENCES CITED Barnett , V. H. , 1916 , Geology of the Hound Creek district of the Great Falls coal field, Cascade County, Montana : U.S. Geol. Survey Bull. 641-H , p. 215 – 231 . Becraft , G. E. , D. M. Pinckney , and S. Rosenblum , 1963 , Geology and mineral deposits...

... of the wells drilled in Potter County between 1932 and 1934 the Oriskany was encountered at depths varying from 4,875 feet to 5,875 feet. A well in the southern part of Potter County on the Marshlands anticline, East Fork district, is reported to have encountered the Oriskany at 6,280 feet (4,344 feet...

... related to the Elkhorn Mountain gabbro, which lies to the north and has yielded U-Pb zircon ages ranging from 1781 Ma (Hedge in Snyder, 1980b ) to 1774 ± 2 Ma ( Pallister and Aleinikoff, 1987 ). Figure 2. Geologic map (upper panel) and schematic stratigraphic and intrusive relationships (lower...