The Following File Is Part of the Grover Heinrichs Mining Collection
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CONTACT INFORMATION Mining Records Curator Arizona Geological Survey 416 W. Congress St., Suite 100 Tucson, Arizona 85701 602-771-1601 http://www.azgs.az.gov [email protected] The following file is part of the Grover Heinrichs Mining Collection ACCESS STATEMENT These digitized collections are accessible for purposes of education and research. We have indicated what we know about copyright and rights of privacy, publicity, or trademark. Due to the nature of archival collections, we are not always able to identify this information. We are eager to hear from any rights owners, so that we may obtain accurate information. Upon request, we will remove material from public view while we address a rights issue. CONSTRAINTS STATEMENT The Arizona Geological Survey does not claim to control all rights for all materials in its collection. These rights include, but are not limited to: copyright, privacy rights, and cultural protection rights. The User hereby assumes all responsibility for obtaining any rights to use the material in excess of “fair use.” The Survey makes no intellectual property claims to the products created by individual authors in the manuscript collections, except when the author deeded those rights to the Survey or when those authors were employed by the State of Arizona and created intellectual products as a function of their official duties. The Survey does maintain property rights to the physical and digital representations of the works. QUALITY STATEMENT The Arizona Geological Survey is not responsible for the accuracy of the records, information, or opinions that may be contained in the files. The Survey collects, catalogs, and archives data on mineral properties regardless of its views of the veracity or accuracy of those data. 10 GEOLOGY AND MINERAL DEPOSITS, LINCOLN AND FLATHEAD COUNTIES STRATIGRAPHY- BELTIAN ROCKS 15 lake. The water from the lake, which is very deep, As the climate gradually ameliorated, the ice for the quartzose rocks is between 0.01 and 1.0 altered shell surrounding unaltered pyrite-bearing mm or more, the average grain size being about now flows northeastward down Logan Creek. stopped advancing, and for a relatively long period .. \ carbonate rock attains a thickness of 2 cm or Few of the moraine-dammed lakes provide the lake level was static. Presumably evaporation 0.1 or 0.15 mm; in the argillite the mean diameter more. such conspicuous evidence of drainage diversion offset melting. A prominent terrace was locally is about 0.05 mm. Small angular quartz particles Clastic rocks in the Missoula Group in as do Bull Lake and Tally Lake, but there are other developed at an altitude of about 4,100 feet (Mc are probably of detrital origin, whereas larger clude quartzite, sandstone, argillite, claystone, and Murtrey and others, 1965, p. 12). Continued warm examples. The whole subject of the interrelation grains exhibit fused or welded boundaries indica siltstone. Angular to subangular quartz particles ship of glacial erosion, glacial deposition, and ing accelerated the runoff, the lake filled to an tive of secondary growth. Magnetite octahedra are most abundant. Sericite, magnetite, ilmenite, altitude of about 4,200 feet, even though the ice drainage diversion is too complex for further con of both primary and secondary origin are perva specular hematite, and chlorite are found in the may have been retreating slowly, and at last the sive throughout the Ravalli, the size ranging be sideration here, however. Striped Peak Formation. Ferruginous quartzose water overtopped the ice dam. Once water started tween 0.2 and 1.0 mm. Other minerals in rocks Kettle holes, swales, and hummocky topo rocks of the Libby Formation in western Lincoln flowing over it, the ice dam could not long persist; of the Ravalli Group include secondary sericite, County are sporadically sericitic and contain some graphy characteristic of ground moraine are it may have failed completely within a few days. leucoxene, and rare chlorite, carbonate, a moder noticeable west of the Stillwater River between chlorite. Rocks above the Purcell Lava in eastern Obviously, no shoreline markings could have de ate amount of biotite, and minor potash feldspar, Flathead County contain quartz, muscovite, minor Lost Creek and Kalispell (Alden, 1953, p. 123) veloped as the water level fell. The effects down plagioclase, zircon, apatite, epidote, ilmenite, tour and also east and north of Kalispell. Similar topo sericite, chlorite, iron oxides, feldspar, glauconite, stream can hardly be visualized. maline, and hematite. Dahlem (1959, p. 32) barite, sparse biotite, epidote, zircon, magnetite, graphy was observed in the Little Bitterroot described magnetite particles in quartz, and Hall At its maximum, Glacial Lake Missoula was apatite, tourmaline, and carbonate. Valley 2 miles south of Little Bitterroot Lake and (1962, p. 29) found inclusions of quartz in magne about 2,000 feet deep just above the ice dam and also about halfway up Evers Creek 3 miles east tite granules, attesting to secondary growth of The Shepard Formation is dominantly calcar covered an area estimated at 3,300 square miles. of Johnson Peak. the quartz and of the magnetite, respectively. eous. Local discontinuous impure limestone beds If the maximum altitude of the water surface is Biotite about 0.20 mm in diameter encloses crystals occur elsewhere in Missoula strata in eastern Flat Drumlins are numerous and prominent only assumed to have been 4,200 feet, the 4,200-foot in the valley of the Tobacco River. They trend of quartz, zircon, and opaque minerals (Latus head County but carbonate rocks are relatively contour on topographic maps would outline the uncommon in the Missoula Group in western southeastward up the valley from Eureka to the extreme extent of the lake, except in areas that zynski, 1962, p. 28). Lincoln County. vicinity of Stryker, which is on the low divide were still covered by ice when the lake was In the Wallace Formation, carbonate-bearing between the Tobacco and the Stillwater drainages. drained. Inasmuch as the ice dam was destroyed strata are sporadically distributed through the Ripple marks, mud-crack casts, flow casts, One other elongate drumlinlike deposit was ob soon after the glacial retreat began, most of the unit, but most of the impure limestone was ob raindrop imprints, clay galls, mud-chip breccia, served 'l4 mile south of Tally Lake, about 15 area in Lincoln and Flathead Counties was still served near the central part of the formation. In crossbedding, salt-crystal casts, scour-and-fil! miles northwest of Kalispell. covered by ice, and therefore most of the lakebed the Piegan Group, of which the P I, Siyeh, and Ps channels, graded bedding, and load casts are wide silts that are found in that area were deposited in units are the approximate eastern equivalents of spread throughout the Belt strata. These features PLEISTOCENE GLACIAL LAKES lakes other than Glacial Lake Missoula. the Wallace, the Siyeh Formation is everywhere aid in interpreting the geologic conditions under which the sediments were deposited. Ripple marks, Lakebed deposits that are definitely assign carbonate bearing but the lower and upper Piegan As the mountain glaciers and the lobes of the mud-crack casts, scour-and-fill channels, cross able to Glacial Lake Missoula are widespread in units contain more argillite and quartzite and Cordilleran ice sheet advanced, the small quan bedding, graded bedding, and load casts also pro the Little Bitterroot Valley, most of which is south less carbonate. tities of meltwater were at first free to escape to vide evidence helpful in determining the top and of the study area. A terrace fill consisting of 20 Carbonate strata are almost everywhere im the Columbia River drainage system, but even base of individual beds where overturning by feet of brownish-gray clay and silt was observed pure, the major rock-forming minerals being cal tually the lobe that came down the Purcell Trench structural deformation is suspected. near Little Meadow Creek, which is east of Hub cite, dolomite, quartz, and sericite. Minor con into Idaho blocked the Kootenai Valley northwest bart Reservoir. Scattered erratic blocks of quart stituents make up about 5 percent of the rock. Throughout the Prichard Formation, relative of Troy and later the Clark Fork Valley northwest zite and gneiss observed in the Niarada area below Grain size of carbonate minerals ranges from about sparseness of ripple marks, mud cracks, and cross of Thompson Falls. Thereafter the meltwater was an altitude of 3,800 feet are ice-rafted material 0.05 to 0.4 mm; angular and subrounded quartz bedding may indicate that the water was deeper ponded behind these ice dams and probably some deposited in Glacial Lake Missoula. grains range between 0.05 and 0.3 mm. The P I than during deposition of Ravalli and Wallace others, forming lakes; the largest was Glacial sediments. Ravalli rocks, including the Appekunny • and P3 units contain quartz, muscovite, sericite, Lake Missoula, which also has been the most Elsewhere in the study area, Glacial Lake Mis chlorite, and minor amounts of feldspar, biotite, and Grinnell Formations east of the Rocky Moun extensively studied. Although a major glacial lake soula could have extended far up the Thompson dolomite, zircon, and leucoxene. Cubes and grains tain Trench, exhibit current and oscillation ripple may have been impounded in the same place and Vermilion Rivers but even if these valleys of pyrite and limonite pseudomorphs after pyrite marks, mud-crack casts, crossbedding, and mud earlier, possibly several times, only the last one were not filled with ice, the lake would have over are common in Wallace and Piegan carbonate rock. chip breccia. In the Grinnell Formation, mud is considered here. topped the divide only at maximum stage, and Wampler and Kulp (1964, p. 1423) observed that cracks are more common than ripple marks.