Landscape Evolution at an Active Plate Margin - Biological Science ...

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6.6 (0.4) The “Ball Dome” east of 395 is a doppler radar, EYX. 12.0 (5.4) Continue past a right turn. 14.0 (2.0) Continue past a road leading east to the former siding of Fremont on the Randsburg Railroad, running parallel to Hwy 395. This railroad was active from 1887 to 1933 (Myrick, 1991), serving rich mines in Randsburg and Johannesburg. Because of the 1,200-foot drop into Fremont Valley, a spur to Goler was never attempted. Processing of the ores from mines discovered in the Rand Mountains initially proved difficult due to the lack of water. For this reason Garlock, with good wells, was the first site of ore milling operations. By 1896 there were 4 short-lived mills at Garlock, one at Mesquite Spring, and Charley Koehn’s mill at Kane Spring. After the Randsburg Railroad was completed to Johannesburg in 1898, Yellow Aster ore was processed by a 50-stamp mill in Barstow. A water line from Garlock to Randsburg allowed a 30 stamp mill at the Yellow Aster mine to become operational in 1899. In 1901 the Yellow Aster added 100 stamps to the existing battery. 17.1 (3.1) The Rand Hills are at 10:00; the 1990s dumps of the Yellow Aster mine are at 11:00; and Red Mountain is at 2:00. 18.8 (1.7) Cross 20 Mule Team Parkway. This road also leads from Mojave northeast to Blackwater Well, Granite Well at Pilot Knob, through Panamint Valley and down Wingate Wash to the Furnace Creek borate deposits in Death Valley (Faye, 1999). 21.6 (2.8) Look ahead to excavations for scheelite placer mining for in the Atolia Tungsten District. Scheelite (calcium tungstate, CaWO 4 ) initially bedeviled dry placer gold miners. They were troubled by fragments of tungsten since it was heavy (specific gravity 6.0) and wound up with the gold concentrate. Scheelite was recognized as valuable in 1903. Claims purchased by De Golia and Atkins, with a contraction of names, became “Atolia.” Ore from lode deposits was initially hand-sorted but a mill was constructed in 1907. The peak tungsten production, nearly $10 million, was between 1916 to 1918, when Atolia boasted a payroll of $60,000 per month. The Atolia Tung–Sun Mining Company began placer mining in Baltic Gulch in 1942. 21.8 (0.2) Enter the Atolia Mining District. The headframe of the Union Tungsten Mine can be seen to the northwest (Fig. 1-1). The Paradox claims are on both sides of Hwy 395. D. R. Jessey and R. E. Reynolds Figure 1-1. Union Tungsten Mine headframe. [J. Westbrook photo] The district was a major producer of tungsten during the early 20 th century. At one point, Atolia had a population in the thousands (Clark, 1997). Interest in tungsten deposits continues to the present but little mining has occurred for the past 40 years. Scheelite, the main tungsten ore, occurs with quartz and carbonates along faults in the Jurassic Atolia Quartz Monzonite (Peck, 1953). The veins strike northwest and deep steeply to both the north and south. They consist of coarse grained scheelite, quartz, and calcite, deposited as open space filling in the fractures. Wall rock alteration has caused pervasive alteration of biotite to chlorite and feldspar to white mica, carbonate, and clays. The district was referred to as the “spud patch” because of the round, light brown nuggets of tungsten. 22.9 (1.1) Enter Atolia. 24.7 (1.8) Continue past a left turn to Randsburg. View northwest of the 1990 Yellow Aster Mine dumps. 25.1 (0.4) Sign: “Entering Red Mountain.” The Kelly silver mine structures are to the west, although the headframe has been dismantled. Initial samples from the mine assayed 300 ounces of silver with three ounces of gold per ton. It became California’s largest silver deposit with over 20 million ounces produced between 1919 and 1942. The ore occurs in quartz– carbonate–chalcedony veins. Silver mineralization consists mainly of Ag–Cu–Sb sulfosalts (miargyrite and pyrargyrite) and Ag chlorides with minor native silver. Arsenopyrite is the chief gangue mineral. Due to the difficulty of milling, native silver was often rejected during processing and large nuggets can still be found on the dumps. 8 2009 Desert Symposium
25.3 (0.2) Continue past Osdick Rd. 25.5 (0.2) View west of remaning Kelly Mine control building. 26.5 (1.0) Continue past Trona Road on the right to Searles Lake (see Reynolds, 2002). Steam Wells Valley is to the north. Some of the pumps on the wells that provided Johannesburg and Randsburg with water were operated by steam, an early use of geothermal power (Mendenhall, 1909; Reynolds, et al., 1998). 28.2 (1.7) Enter Johannesburg and Kern County. Randsburg and Johannesburg were the twin metropolises of the Rand Mining District. Randsburg was the company town, while Johannesburg was a planned community for miners with families (Clark, 1997). They functioned as major trans-shipping points for rail and stage lines. Ore from the district was initially shipped south to Barstow for milling, but with the construction of a 100-stamp mill in 1901 the district began to thrive. Large-scale gold mining continued until 1918. Gold production from the district was substantial into the 1930s and early 1940s, and there has been intermittent mining since, most recently from 1989 to 1995 at the Yellow Aster. Total estimated production from Randsburg mines up to 1940 is estimated at $40 million. The mine was shut down in 2004 and the dumps and heap leach piles have been “reclaimed.” The principal rocks underlying the Rand district are Precambrian Rand Schist and Jurassic Atolia Quartz Monzonite. The Rand Schist is chiefly biotite schist with smaller amounts of amphibolite and quartzite. Most of the lode-gold deposits are in veins along faults, except at the Yellow Aster mine where the gold occurs in a series of closely spaced veinlets in areas of intense shearing. The veins do not have a well defined strike; high grade ore zones most commonly occur at or near vein intersections or in sheared and brecciated zones. The ore consists of iron oxide-stained, brecciated and silicified rock containing fine-grained gold with varying amounts of sulfides. The sulfides increase at depth, but the gold values decrease. Mining stopped at a depth of 600 feet where unoxidized sulfides were found in the veins. 29.2 (1.0) Prepare for left turn across oncoming traffic. 2009 Desert Symposium Landscape evolutuion at an active plate margin: field trip 29.4 (0.2) TURN LEFT (west) to Randsburg via the Redrock–Randsburg Road. Randsburg has a museum and a recently active single stamp mill. 29.9 (0.5) Disposal Site signs. TURN RIGHT (north) on Goler Road, and proceed north 4.2 miles to Garlock Road. View right (northeast) of Summit Diggings district. Placer gold deposits to the northeast are called Hard Cash Gulch and Summit Diggings (Reynolds, et al, 1998). Auriferous gravels of Summit Diggings may have been derived from Goler Gulch, three miles to the west. Right lateral restoration of movement on the left lateral Garlock fault would place auriferous gravels at the mouth of Goler Gulch. Farther east, the trace of the Garlock fault on the south shore of Searles Lake at the 2,250 foot shorelines is marked with tufa dated at 50,000 ka. Since the dated shorelines are not cut by the Garlock fault, that date constrains the latest movement on that portion of the fault to greater than 50,000 ka (Smith, 1964). We are entering Fremont Valley. 31.3 (1.4) Pass gravel dumps from hydraulic mining operation. 32.9 (1.6) Pass through low hills of Pleistocene alluvium elevated above axial drainage of Fremont Valley by the south-side up Cantil Valley Fault. 33.4 (0.5) Cross Fremont Wash and Cantil Valley Fault. 33.8 (0.4) Railroad crossing, watch for trains. Prepare to turn left (west). Figure 1-2. Shuttle Radar Topography Mission (SRTM) image looking west along the Garlock fault. El Paso Mountains are in the foreground and Tehachapi Mountains in the background; San Gabriel Mountains on the distant skyline. 9
Page 1 and 2: Landscape Evolution at an Active Pl
Page 3 and 4: Table of contents Landscape evoluti
Page 5 and 6: Evaluation of minor and trace eleme
Page 7: Landscape evolution at an active pl
Page 11 and 12: and Wesnousky, 1994). Reported rate
Page 13 and 14: into six units which range in age f
Page 15 and 16: Nevada & California railroad were u
Page 17 and 18: een built to meet the growing deman
Page 19 and 20: Figure 1-10. Offset drainages of Lo
Page 21 and 22: tary and metavolcanic units are lar
Page 23 and 24: Landscape evolutuion at an active p
Page 25 and 26: the Independence fault is dip-slip,
Page 27 and 28: Figure 1-18. Upper—view to the no
Page 29 and 30: 2009 Desert Symposium Landscape evo
Page 31 and 32: eruption of the Long Valley caldera
Page 33 and 34: Figure 2-2. Collapsed aqueduct pipe
Page 35 and 36: 63.7 (0.4) PARK at turnout. STOP 2-
Page 37 and 38: Sierra Nevada fault system has offs
Page 39 and 40: Landscape evolutuion at an active p
Page 41 and 42: (Cleveland, 1962). The rhyolite has
Page 43 and 44: ahead on the left. 95.6 (1.2) Stop
Page 45 and 46: ay. The big 40m dish is now used by
Page 47 and 48: cupied in 1865, and finally abandon
Page 49 and 50: Figure 3-6. Independence dikes. [S.
Page 51 and 52: which has significant concentration
Page 53 and 54: The Pliocene (Blancan NALMA) Coso F
Page 55 and 56: Current Research in the Pleistocene
Page 57 and 58: Quaternary data and references: A c
Page 59 and 60:
and volume, p. 26-35. Smith, G. I.,
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Stolzite and jixianite from Darwin,
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(112) (Palache, et al., 1951). The
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ing gold and silver deposits. From
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the United States. Several small de
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at the base of the Lost Burro were
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silver-lead ore and is the one exce
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Significance of the Independence Di
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Independence Dike Swarm Figure 2: C
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40 km of displacement was too low.
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dominant northwest strike. Dikes wi
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Moore, J.G., 1963, Geology of the M
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summarizes the formations you will
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The Perdido Formation conformably r
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note the spheroidal weathering patt
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Lower Cambrian-Precambrian stratigr
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lus. Six to ten species of echinode
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The Olancha Dunes, Owens Valley, Ca
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Triassic ammonoids from Union Wash,
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Archaeocyathids from Westgard Pass,
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Basaltic volcanism in the southern
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Basaltic volcanism in the southern
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oxene, whereas Pleistocene basalt i
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in much slower rates of displacemen
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Vegetation of the Owens Valley and
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cone and limber pine woodlands and
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Figure 21. The alpine zone of the W
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The rush from the Kern River mines
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The rush from the Kern River mnes i
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2009 Desert Symposium The rush from
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mining company; and A. K. Warner an
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chinery and the castings for a smel
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Advertisement for the Hobard and Re
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November 1864, a series of lines be
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When the geologist W. A. Goodyear v
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Montgomery City Alan Hensher, 593 C
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The Blue Chert Mine: an epithermal
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2009 Desert Symposium The Blue Cher
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2009 Desert Symposium The Blue Cher
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Tectonic implications of basaltic v
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The Goler Club Figure 2. Outcrop ma
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closest relatives were early Paleoc
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The Goler Club Figure 8. Goler Club
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prospecting, Baum wandered over to
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ejonian age (Thewissen 1990; Lofgre
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Fish Creek rhythmites and aperiodic
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We analyzed each of the three rhyth
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Figure 10. Threshold rhythmite prod
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Holocene slip rate and tectonic rol
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Figure 2. Camelops sp. (camel) meta
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moist, brush- and grass-covered, fr
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Recent records of fossil fish from
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geal arches are similar to S. b. sn
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elatives seen in Pliocene and early
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Jennings, C.W. 1958, Geologic map o
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Competing mesquite and creosote dun
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Figure 9. Sheetwash area near the w
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Page 191 and 192:
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The Oak Crrek mudflow of July 12, 2
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Photo 8. Deeply incised channel of
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than the north fork because of the
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mass contents of Gram negatives (sa
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to different uses. I do not suggest
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Geochronology and paleoenvironment
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Reproductive ecology of female Sono
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Garbage production is the other sid
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ties and preparation for use of som
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