The Black Rock Desert Landscape
The Black Rock Desert Landscape
By Mike & Barbara Bilbo, Socorro, New Mexico, January 3, 2008
The Black Rock Desert landscape consists of the largest playa in North America and surrounding wind-formed mounds, sheet sands, dunes, alluvial slopes, terraces, foothills and mountains. These elements along with the occurrence of hot springs form a significant visual resource which is attracting increasing visitor use. At the center of this landscape is the Black Rock Playa, a relict lake barren except for sparse, local occurrences of stunted bud sage and greasewood in disturbed areas. Underlying the playa are thousands of feet of water-saturated saline silt and clay with interbeds of fine-textured lacustrine silt and clay sediments interbedded with coarse deltaic, beach, offshore and lake deposits as well as several hardpan layers (Sinclair 1963, table 4).
Coarse alluvial fan deposits interfinger the finer lake deposits around the basin margin and for some distance toward the basin center bed of Pleistocene Epoch Lake Lahontan, the lowest surface in the Black Rock Desert and which covers approximately 300 square miles. The Black Rock Desert, one of the major structural basins in Nevada (Sinclair 1963, p. 1), is bounded on the east and west by north-south trending fault block mountain ranges (the Black Rock and Granite ranges respectively). The basins are down-dropped blocks relative to the mountain blocks and have debris-filled, U-shaped floors underlying the present landscape. Playa elevations vary from about 3,500 feet above sea level at the southwestern edge near the town of Gerlach, to nearly 4,000 feet along the margins to the north and northeast. The higher elevations are Granite Peak, 9,510 and about 6,000 feet on associated ridge-crests; Black Rock, 4,240; Pahute Peak (Big Mountain), 8,508; and Donnelly Peak, 8,491.
Mountain slopes are steep and angular and support scrub vegetation with few trees. Along lower slopes sagebrush and greasewood form a characteristic landscape component on deep soils. Salt-tolerant shrubs such as greasewood grow in playa margin dunes, mounds, and sand sheets. The playa is barren except for sparse, local occurrences of stunted bud sage and greasewood in disturbed areas. Underlying the playa are thousands of feet of water-saturated saline silt and clay with interbeds of fine-textured lacustrine silt and clay sediments interbedded with coarse deltaic, beach, offshore and lake deposits as well as several hardpan layers (Sinclair 1963, table 4).
Coarse alluvial fan deposits interfinger the finer lake deposits around the basin margin and for some distance toward the basin center. The depth to the water table varies but is generally about 10 feet below the surface, although it lies about 5 feet below under nearly 200,000 acres of the playa (Sinclair 1963, p. 15). In several locations the water table intersects the playa surface to form ponds or saturated surface sediments including the Quinn River sink, the upper reaches of Mud Meadows Creek, and the area where the Bowen Creek drainage reaches the playa.
The playa is the discharge location for a runoff area of about 2,600 square miles. A major portion of the runoff comes from the Quinn River valley which extends from southeastern Oregon, about 150 miles to the north. Numerous, small ephemeral and one intermittent stream (Mud Meadows Creek) contribute the rest. During late fall, winter and spring, when 70% of the annual precipitation occurs, the playa surface is normally wet and may be covered with as much as five inches of standing water (Sinclair 1963. P. 2). During this time superficial surface impacts from motorized traffic are minimized or obliterated. Surface clays swell and salts dissolve, surfaces are fluffed up through freeze and thaw action and wind sweeps standing water around, scouring and planing the surface (Sinclair 1963, p. 6).
This action also tends to smooth out areas of eolian deposition that resemble small dunes which form across the playa surface, often in locations where a natural obstacle, such as a rock or plant occurs or where event activities and structures have caused wind eddies to sweep up and deposit sediments.
The playa surface is an essentially flat, non-vegetated ephemeral lakebed. Variations in surface relief develop seasonally and are not readily apparent to the eye. Wind effects change the shape and size of dunes, sheets of silt and sand, and mounds. Winter rains and spring snow-melt runoff make incipient drainage channels a few inches deep wherever runoff channels intersect the playa edge. Channeling is greatest where there are loose silt and clay sediments on the playa surface. These channels change position seasonally. A wide, shallow depression exists where the Quinn River ponds on the playa (Quinn River Sink) south of the Black Rock Range. Standing water persists there well into summer and occasionally throughout the year.
As the playa surface dries out during early summer, desiccation polygons form (Wilden and Mabey 1961; Sinclair 1963, p. 6). They are a foot or so in diameter and the surrounding cracks may extend several feet below the surface. The polygons form because the clay sediment shrinks as it dries. The polygon shape develops due to structures inherent in clay. A white, saline mineral crust, precipitated from the evaporating water, covers the polygons but is blown away along with loose clay and silt particles as summer progresses and impact from vehicles and wind occur. The hard flat surface attracts diverse forms of recreational activities.
The Earth's Curvature?
There is a visible convex profile to the playa surface when viewed from some points. It is probably due to the swelling of clays in the basin sediments and their water-saturated conditions (Zielinski 1998, personal communication). A past interpretation has been to ascribe the apparent curvature as the actual earth's surface curvature and to the moon's tidal influence.
In reality, the earth's surface curvature can only be seen from elevations about 80,000 feet above the earth's surface, as illustrated in photographs taken during U-2, Gemini, Apollo, SKYLAB, and space shuttle missions (Baker 1981).
Dr. Elbow (2000, personal communication) provides this view:
Given the scale of Earth, one has to reach a considerable altitude before curvature becomes perceptible. From the ground one can infer curvature by noting an object rising or dropping over the horizon. However, in the latter case the observation could only be made at sea. On land there are too many surface irregularities for this to be possible. You indicated that Black Rock Desert extends some 27 miles on its longest axis. Even the flattest surface of this size might show very gentle up or down warps that could appear to be curvature but are actually related to local surface irregularities. Depending on the local soils, underlying rock types and structure, and on local and large scale tectonic processes, these surface warps might change from time to time, as well. Flat lake bed deposits fit this description very well. Even in the unlikely event that they were deposited with perfect flatness, the dynamism of Earth's crust makes it unlikely that they would remain that way for very long. What appears to be Earth's curvature at Black Rock Desert is most likely local Earth surface variations.
Playa Margins: Mounds, Dunes, and Biological Soil Crusts
In the playa margins the surface is irregular and soft, consisting of dunes and silt and clay parna deposits (Soil Survey Staff 1996; Peterson 1981, p. 28), sand sheets, ridges, vegetation-stabilized mounds of eolian clay and silt particles (Blank et al. 1998; Young and Evans 1986) and phreatophyte mounds (Walker and Motts 1970, p. 151).
The deposits referred to as sand sheets consist of unstructured eolian deposits of clay and silt particles. These various features range from a few inches to about 30 feet in height. Several mound or dune areas are composed of particles, usually angular, of quartz, feldspar and mafic minerals derived from weathered igneous rocks and deposited by water and wind action. These features may be dunes, e.g. having a specific internal structure and having slip faces on their leeward slopes. No field study has been carried out to show that these are true dunes. The principal location in the area of these deposits lie north of Double Hot Springs along the west base of the Black Rock Range. Another is located east of the Black Rock Desert area just north of Sulphur. Salt-tolerant vegetation populates most of these features.
Dunes, with their characteristic shape and structures are not as common in the Black Rock Desert as might be thought. No source of fine sand exists in the area but there are abundant silt and clay particles on and around the playa. The wind constantly moves this material and it is incorporated into various margin features where some is captured by vegetation. Some becomes part of sheet sands (actually mostly clay and silt), while some develop into true dunes, in this case parna dunes, a term describing eolian features consisting of aggregates of clay and silt particles (Soil Survey Staff 1996, p. 28). Parna dunes are located in several locations on the playa.
Where vegetation takes hold, eolian particles are captured by plant roots and stems, eventually forming semi-permanent mounds. A mound may begin around one plant. As mounds enlarge they will coalesce and the environment, for a more diverse plant community, will develop due to the establishment of soil biological crusts (Belnap and Gillette 1998), the accumulation of organic matter and the protective cover of plant structures. Salinity is reduced in the mounds for decades but eventually it will increase to a point where only plants tolerant of excess salinity remain. At some point salinity may become so high that no plants survive or seedlings grow. This process, in undisturbed areas, may require perhaps 100 years. Without vegetation, the mounds will gradually collapse (Blank et al. 1998, p. 227).
Stabilizing mineral and biological soil crust develop on the surface of these features and are vulnerable to disruption by vehicle, animal and human impacts. Cryptobiotic or biological crust forms through the action of living organisms such as cyanobacteria, green algae, lichen, mosses, and microfungi (Belnap and Gillette 1998, p. 134). Once crusts are broken, underlying soils are subject to wind and water erosion leading to loss of favorable growing conditions and soil fertility. Continued disruption can lead to accelerated erosion. Such areas then become ever-changing, soft accumulations of unconsolidated sediments in which plants cannot become established, animal habitats are reduced or disappear, and vehicles can become stuck whether the sediment is wet or dry ("bug dust"). Recovery to a stable landscape is on the order of hundreds of years (Blank et al. 1998; Lathrop 1983).
Recently part of the Nobles National Historic Trail near Trego Hot Spring was identified due to cryptobiotic soil covering the trail trace. At the same location were hand-forged wagon parts and other artifacts corresponding with the early 1850's.
Alluvial fans cut by arroyos, flank the mountains ranges, ending at the playa's edge. Sagebrush grows in moderate density on the fans and the soil surfaces are protected by pebbles and cobbles along with biological crusts. Within these gently sloping accumulations of sand, gravel, cobbles, and boulders lie fresh water aquifers carrying water from mountain slopes and drainage into the playa basin. Over thousands of years of erosion from the mountains in the basin, alluvial fans extended into the basin, before Lake Lahontan existed, during its different water levels, and after. The fan material interfingered with fine-grained lake sediments as the water levels rose and fell. The basin-ward ends of fans are now buried under the playa surface from the base of the playa sediments to the top. Aquifers in the alluvial fans carry water into the basin sediments, contributing to the saturated conditions in them. Several dug or drilled wells have intersected the aquifers, resulting in artesian flows which were originally intended for farming use but are now wildlife habitats and sought after for recreation. The dug, or flowing, wells are currently part of the landscape as a result of shrub and tree establishment and an oasis-like environment. The transition from alluvial slopes and the playa surface and margins is marked by the appearance of salt-tolerant species such as saltgrass, greasewood, and shadscale (Sunzeri 1975, p.37).
Around the playa margins the lower reaches of fans are covered by mounds and associated features. Among the mounds appear hot springs fed by water percolating deep along the curved trace of a fault which allows the water to be heated by geothermal sources lying thousands of feet below the playa surface. Saltgrass and several species of salt-tolerant shrubs are spaced evenly across the mound fields and are best developed around the springs. Fault trace lines and the springs appear east of Gerlach on the south side of the playa. These are manifested by the presence of a thermal spring at a locality generally known as Garrett Ranch. The fault line heads northeastward from the Garrett Ranch to Trego Hot Spring, a popular camping and off-highway vehicle use area. The spring pool is above the playa surface in a vegetated dune and mound area.
Nineteenth-century emigrants dug a trough from the hot pools to allow water to cool enough for livestock to drink. The trough is now used for bathing although the high alkalinity is a deterrent to some. Wildlife habitat is well developed around Trego Hot Springs but is becoming degraded due to easy vehicle access. Vegetated and stabilized mounds are becoming increasingly compacted, the biological soil crust disturbed and vegetation is not regenerating in large areas. Areas of destabilized mounds have become soft enough to create broadening areas in which vehicles may become stuck.
The fault line associated with the occurrence of hot springs in the Black Rock Desert area trends northeastward from Trego well below the playa towards Black Rock. The Black Rock is a landmark and special place for Native Americans, Euro-American explorers and emigrants, and recreation-seeking escapees from the contemporary urban frenzy. Black Rock Hot Spring comes to the surface on the fault line just west of Black Rock in an interesting, clear pool lined with tufa, a calcareous and siliceous deposit unique to hot springs. Tufa towers occur as amorphous landscape features at several locations beyond the Black Rock Desert area where springs are marginally active. There are several near State Highway 447 between Nixon and Empire. Others occur near Interstate 80 between Fernley and Lovelock.
The temperature in Black Rock Hot Spring averages 133°F. Bubbles with a sulphurous odor can be observed emanating from small holes in the tufa deposit in the pool bottom. Water from Black Rock Hot Spring seeps through margin sediments and out onto the playa. This and other springs can easily be seen from the air in fall, when thick dormant sedge growths turn an orangish color.
From Black Rock Hot Spring the fault line trends northward and about five miles further along the fault trace is another significant hot spring called Double Hot. The water here has been measured as reaching boiling temperature (Sinclair 1963, table 3). A more recent, informal, measurement showed a temperature of 185°F
Sept.22. In the first part we reached a pretty clear sparkling rill, about six feet broad, and a few inches deep; when to my astonishment the mules halted short at the edge, and refused in spite of the whip and shouting, to put a foot it! - I guessed there might be a vapor from it, but on putting my hand in, found it quite hot - not sufficiently to scald, however...Next, on left, observed a cluster of hot Spring mounds, with their circlets of marsh and tall green grass. - In one lay a dead ox, apparently fell there yesterday; one hind leg in the basin of hot water, which had so well cooked it, that naught but white bones and tendons were left, of that limb, as high as the water had influence. Bruff 1849.
Over the years there have been a number of fatalities and serious scalding incidents when people or their pets entered or fell into several area hot springs. While the hot springs are historical and interesting to visit, the BLM does not maintain them as recreational resources and visitors are advised of these as scalding hazards, and that bathing in them is at their own risk.
The water in all the hot springs is highly mineralized (alkaline) which makes it difficult, when cooled, to drink, and very drying, even irritating to the skin. The potability of the hot springs is unknown - some emigrants described serious gastric effects from drinking the water. Hot spring water and mud is highly alkaline and mineralized and dries the skin out. The whitish tufa deposits seen at some hot springs and coating rocks in edge areas is calcium carbonate, the same mineral as cave formations. Algae species flourish in all the springs. These hot springs are apparently related to the same volcanic systems that drive Mount Lassen, Mammoth Lakes and other volcanic areas in California and Oregon, and can vary in temperature from time to time. The hot springs are located on an active fault along the eastern margins of the West Arm, extending from the Gerlach vicinity, north to the Soldier Meadows area.
The fault line continues northwest to Soldier Meadows and beyond. Hot springs occur at Soldier Meadows, where a series of interconnecting faults occur, as well as at locations further on outside the Black Rock Desert area. But nowhere do the hot springs form such picturesque and interesting features as the ones occurring in the Black Rock Playa margins. Even though water temperatures in the springs can be as high as boiling (210°F.), the moisture around them allows shrubs and salt grass to grow in greater density than further away from the springs, creating wildlife habitat and a pleasant visitor experience.
In several locations there are mound springs (Meinzer and Hare 1915), features several or more feet in height, with a spring, usually in a central position. Vegetation grows around the spring pool margins and sparsely on the sides of mounds. Coyote Spring is a spring mound located on the playa near the southern edge and the Garrett Ranch. In the 1950's a well was dug at the ranch and soon after the flow in Coyote Spring was seen by area residents to have dropped noticeably. There is no record it its flow prior to that time. The water temperature has been recorded at 60°F and the flow rate about 1 gallon per minute (or less now, as the last known measurement was over 25 years ago) (Sinclair 1963, table 3). The spring mound is about 15 feet high and 50 feet wide. The mound was built as a result of wind blown sediment being captured by vegetation which had become established around the initial spring pool which most likely resembled a small water pool several feet in diameter. Over centuries sediment has accumulated around vegetation at Coyote Spring and more vegetation has grown resulting in the spring mound seen today. As the mound height increased, the spring became higher accompanied by upward development of tufa lining the spring channel or throat. Coyote Spring may eventually cease to exist. The slow flow rate could be suppressed when sediment fills in the pool basin as a result of human-induced impact at the spring pool rim. Several mound or dune areas are composed of particles, usually angular, of quartz, feldspar and mafic minerals derived from weathered igneous rocks and deposited by water and wind action.
South of Coyote Spring lie a unique series of mounds in relative straight alignment. The morphology of these features is not known but they could be a line of developing spring mounds aligned along a crack, resulting from a fault or subsidence under the playa surface, which extends deep enough to penetrate some hardpan layers under the playa and intersect the water table which may be ten feet or so under the surface. Water from saturated sediments under the playa could then rise to the surface under artesian pressure.
Sediment comprising the mounds may have obscured the pools, but wind-blown sediment continues to accumulate. The origin may also be due to mad-made features such as a trench made many years ago in which vegetation became established. The water in these possible spring mounds probably comes from aquifers in alluvial fans extending from the mountain slope and out under the playa and from which water in the Garrett Ranch and other dug wells originate.
Relict Features of Lake Lahontan
Up-slope, alluvial fans abut the steep mountain slopes and drainage-ways. The mountain slopes show the former presence of Lake Lahontan (Russell 1885) by traces of wave action remaining as shoreline marked by the presence of wave-cut and wave-built terraces, bars and other features, several of which are also seen at the current playa surface level. Wave-cut and built terraces in the Black Rock Desert basin are not as visible as at other locations in the Great Basin. There were at least three deep lake cycles during the existence of Lake Lahontan (Russell 1885; Wallace 1961) as evidenced by clay and silt lacustrine sediments interbedded with layers of alluvial sand and gravel. The highest lake level reached an elevation of about 4370 feet above sea level, evidenced by a wave-built terrace of unsorted gravel called Lahontan Beach (Russell 1885, p. 101).
A lower water line is located about 30 feet below Lahontan Beach which indicates a long period of wave cutting which left a terrace a hundred or more feet wide. The wave-built terrace of Lahontan Beach rests on this wide, wave-cut terrace. A little less that 100 feet above the current playa surface is a wave-cut terrace which marks the last stable shoreline before the lake completely evaporated about 6000 years ago (Russell 1885).
Along the basin-ward slopes of the Selenite Range are several shoreline terrace remnants which can be located by viewing the slopes on a clear day early or late in the day. The distinguishing aspect is a level line of narrow surfaces which are inclined gently toward the playa and are even with each other across the mountain slopes. At one point there is a noticeable flat area on a spur off the mountains toward the playa. East and west of the spur are more subdued, possible shoreline traces. This feature may have instead been created by faulting during which the north (playa-side) end of the spur was down-dropped.
The probable time of faulting was pre-Pleistocene. Wave cutting may have also contributed to its broad appearance in contrast to adjacent traces. Near the mountain slope-side of the terrace are possible remains of a wave-built terrace (unsorted debris left on the wave-cut terrace by wave action on the steep mountain slopes) and/or debris accumulated from the slopes above along a fault trace. Research has shown that the terraces are not absolutely level. On slopes adjacent to the deepest parts of the lake basin terraces have been recorded as lying about six feet higher that those adjacent to shallow water parts of the lake basin due to compression from the weight of the water and the land-surface rebound (isostatic) when the water was gone (Adams 1990).
As water evaporated over hundreds of years there were a number of short-term stable lake levels. Gravel and sand deposits formed barriers which contained lake waters in small basins or microplayas in the mountains as the lake level dropped and which now appear as small, elevated playas. Two of these features, Lower and Upper High Dry Lakes, lie east of Black Rock in the southern end of the Black Rock Range.
Another accumulation lake-deposited sediments appear as a causeway on the east side of Black Rock, connecting it to the Black Rock Range. Southeast of Black Rock a well-developed spit (Wilden 1964, p. 71) extends from what was a final shoreline, and curves northeastward around a relect of a small bay or lagoon of perhaps 6,000 years ago. Materials forming the spit were deposited by horizontal currents along the shore on the lee side of a point of land. A large offshore bar of the same time-frame is located along a western portion of the playa West Arm.
From mid-Pliocene to the early Pleistocene the mountains surrounding Lake Lahontan and other Great Basin areas were covered by mesic forests much like that of present West Coast mountains today. Toward the later part of the Pleistocene the Sierra Nevada had been uplifted to an elevation at which moisture from eastward moving oceanic air masses was largely blocked and the arid and semi-arid conditions which characterizes the Great Basin developed, the forests gradually disappearing. Leaf imprints in shale and petrified wood remain as evidence of this ecosystem (Axelrod 1962, 1956).
From about A.D. 1600 to about 1800 a cooler climate returned and glaciers expanded again in the Sierra Nevada (Curry 1969). The cooler conditions were also wetter and the lakes in Lahontan's basins reappeared (Morrison 1964; Russell 1885). Lake depths are unknown but it is accepted that nothing like Lake Lahontan existed. Research in the Carson Sink, another basin left by Lake Lahontan located about 100 miles southeast of the Black Rock Desert, has documented the existence of lake in that area perhaps as recently as the 19th Century (Blank et al. 1998). Drought conditions preceded the neo-glacial period and returned afterward, continuing today, part of natural, long-term climatic variability.
When the lake was finally gone and the climate became warmer and drier, all that was left of that immense body of water, once over 500 feet deep (Adams 1990) over the Black Rock Desert, was the playa, a wind-swept plain covering nearly three hundred square miles. For over five millennia it has remained much as it is today. Except for the stream of vehicles of all kinds which appear during the dry season. And the people in them with all sorts of gear. And some dogs, maybe a few cats. In winter, the playa is empty for awhile again.
The Black Rock Desert: A Visual Resource
The mountain slopes are angular and steep, characteristic of arid land landscapes. Faulting and variations in lithology have contributed to the appearance of the Black Rock Desert landscape features. Dark igneous rocks contrast with the pale colors of undifferentiated Tertiary sediments, most of which have been transformed into multicolored pastel landscapes by hydrothermal alteration processes which have also created the mineral potential of the area. The brightness of a dry summertime playa and a clear blue sky make the mountains appear as distant apparitions on a far horizon, enhanced by a spot of Calico. During winter, a blue-gray sky above shimmering gray water, dove-gray mud, neutral gray sagebrush and greasewood covered foothills and alluvial fans, and charcoal-colored mountains are highlighted by the ever-colorful Calico Range. The Black Rock Desert landforms are a visual resource above the rest.
The information contained in this general landscape description is based on the information in Russell (1885) and Adams (1990), which covers the entire Lake Lahontan basin, discussions of landforms in several geologic studies, consultation with others, and field observations of this writer.
Adams, J.A. 1982. Desert Soil Compaction Reduces Annual Plant Cover. California Agriculture 36(9-10): 6-7.
Adams, Ken D. 1990 History of Isostatic Rebound of Ancient Lake Lahontan, Nevada and California. Unpublished M.S. Thesis, University of Nevada, Mackay School of Mines, Reno.
Axelrod, D.L. 1956. Mio-Pliocene Floras from West-central Nevada. University of California, Publications in Geological Sciences 34(2):91-160.
Axelrod, D.L. 1962. A Pliocene Sequoiadendron Forest from Western Nevada. University of California, Publications in Geological Sciences 39(3):195-267.
Barker, C.E. 1996. Resource Assessment of the Bureau of Land Management's Winnemucca District and Surprise Resource Area, Northwest Nevada and Northeast California – Geochemical Analysis and Thermochronologic Modeling to Evaluate Conceptual Petroleum Plays. U.S. Geological Survey, Open-File Rept. 96-051.
Belnap, Jayne and Dale A. Gillette 1998. Vulnerability of Desert Biological Soil Crusts to Wind Erosion: the Influences of Crust Development, Soil Texture, and Disturbance. Journal of Arid Environments 39(2): 133-142.
Blank, Robert R., James A. Young, James D. Trent, and Debra E. Palmquist 1998. Natural History of a Saline Mound Ecosystem. Great Basin Naturalist 58(3): 217-236.
Brainard, Jeffrey 1998. Patton Tank Marks Suggest Long Recovery. Science News 154(6):87.
Curry, R.R. 1969. Holocene Climatic and Glacial History of the Central Sierra Nevada, California. Geological Society of America, Special Paper.
Elbow, Gary S, Ph.D. 2000. Professor of Geography, Department of Economics & Geography, Texas Tech University, Lubbock, Texas. Personal Communication.
Meinzer and Hare 1915. Geology and Groundwater Resources of the Tularosa Basin, New Mexico. U.S. Geological Survey Water-Supply Paper. U.S. Government Printing Office, Washington, D.C.
Nevada State Engineer 1996. Well Logs and Drillers Report. Nevada State Engineer's Office, Water Resources Division, Carson City, NV
Peterson, F.F. 1981. Landforms of the Basin and Range Province Defined For Soil Survey. Nevada Agricultural Experiment Station, Technical Bulletin 28, University of Nevada, Reno.
Russell, I.C. 1885. Geological History of Lake Lahontan, a Quaternary Lake in Northwestern Nevada. U.S. Geological Survey, Monograph 11.U.S. G.P.O., Washington, DC.
Sinclair, W.C. 1963. Ground-water Appraisal of the Black Rock Desert Area, Northwestern Nevada. Nevada Dept. of Conservation and Natural Resources, Ground-water Resources-Reconnaissance Series, Report 20. Carson City.
Soil Survey Staff, National Resources Conservation Service 1996. National Soil Survey
Handbook. U.S. Government Printing Office, Washington, D.C.
Sunzeri, Christine C. 1975. The Lean Brown Land: A Study of the Relationship Between
Landform and Plant Ecology in the Black Rock Desert. Unpublished M.S. thesis, University of California, Santa Cruz.
Wallace, R.E. 1961. Deflation in Buena Vista Valley, Pershing County, Nevada. U.S.
Geological Survey Research 1961, U.S. Geological Survey Professional Paper 424-D, pp. C10-C13.
Wheeler, Session S. 1978. The Black Rock Desert. Caxton Printers, Ltd., Caldwell, ID.
Wilden, Ronald and D. R. Mabey 1961. Giant Desiccation Fissures on the Black Rock and Smoke Creek Deserts, Nevada. Science 133(3461):1359-1360. AAAS, New York, NY.
Wilden, R. 1964. Geology and Mineral Deposits of Humboldt County, Nevada. Nevada Bureau of Mines and Geology, Bulletin 59, University of Nevada, Mackay School of Mines, Reno.
Young, James A. and R.A. Evans 1986. Erosion and Deposition of Fine Sediments From
Playas. Journal of Arid Environments 10(2):103-115
Zielinski, M. 1998. BLM Soils/Vegetation Specialist, Winnemucca Field Office, Nevada. Personal Communication.
Acknowledgement: We'd like to thank Louise Johnson for helping with formatting for [the Word doc] version. Uploaded and formatted for Friends of Black Rock, September 2009.
The Leave No Trace Spirit: "A Healthy Playa is a Happy Playa."
Mike Bilbo photo 9/21/98