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Hiking in Great Basin National Park can be a fun and rewarding experience as in other national parks. It is a great way to both see and experience the park.
Great Basin National Park is a mountain park. Roads and trails open seasonally as snow conditions permit. Summer months are the best for access to the high country. The road from town of Baker to park visitor center is open year round.
| Bonneville Cutthroat Trout | Hiking Tips | Hiking Trails |
| Fishing Guide | Lehman Cave Dates | Lehman Cave Ecology |
| Lehman Cave Info | Lehman Cave Geology | Lehman Cave Tour |
Great Basin National Park is best explored by hiking. This is a park where it is possible to experience true solitude. Make sure you are prepared before starting any hike. Bring clothing for all types of weather, as weather may change rapidly, especially at high elevations. Eat and drink plenty while hiking. The trails listed below are only ideas to get you started. Rangers can recommend possible routes in even more remote areas of the park. Hiking cross-country can be an exciting challenge for the more experienced hikers and route-finders. Consider extending your hike by spending the night in the backcountry. Voluntary registration forms are at the visitor center. This is your park, please protect it. Always try to leave areas cleaner than how you found them. Use a park map to plan your trip. More detailed hiking maps are available at the park visitor center.
Most of these trails reach an elevation of 10,000 ft / 3,048 m and above. At higher elevations, people tire more easily. Pace yourself. If you experience symptoms of altitude sickness, (dizziness, nausea, headache, or difficulty breathing) return to a lower altitude immediately.
Taking water is essential. At least one quart / one liter per person for the shorter hikes is recommended. Portable water is available at the Visitor Center and sometimes at the campgrounds.
Wear proper foot gear. Most of the trails are studded with sharp rocks; hiking boots are recommended. Wear layered clothing. Weather conditions at higher elevations can change quickly. Be prepared for sudden storms of rain or snow.
If clouds begin to build, get off the ridges and move to lower ground. Lightning strikes often in the high country.
Be a conscientious hiker. Carry out trash and dispose of waste properly.
Check at the Visitor Center for current road conditions.
Rattlesnakes
While walking along a rocky, streamside trail a hiker hears an electric BUZZZ just a step ahead. The hiker is carrying a long walking stick which is pointed instinctively at the source of the sound. The hikers next action will depend upon their knowledge of the Great Basin rattlesnake.
Great Basin rattlesnakes (Crotalus viridis lutosis) are the only venomous reptiles in most of the Great Basin desert. They are best identified by their blunt, rattle-tipped tail & thick, stocky bodies. Adult Great Basin rattlesnakes average 30-36 inches in length, and are tan to yellow in color, with a series of darker oval blotches on their back.
Great Basin rattlesnakes may occur up to 11,000 feet in elevation, but are more common below 8,000 feet, in a variety of habitats- greasewood/shadscale, sagebrush, pinyon/juniper, & fir/spruce. The unifying characteristic of rattlesnake habitat in the Great Basin is rock. Great Basin rattlesnakes hibernate in dens, southern exposed rock outcrops, during the winter, emerging in May to bask in the spring sun. Males and non-reproducing females disperse into surrounding areas to forage for mice, rats, ground squirrels, gophers, birds, & lizards. A mature male may move up to 2.5 miles away from the den.
Gravid (pregnant) females remain near the den, basking frequently to facilitate proper development of their developing embryos. In mid to late September they give birth to 5-8 live baby rattlesnakes, remaining with them for the first 7-10 days of their life. Mortality is high among newborn rattlesnakes with less than 10% surviving to sexual maturity.
By late September the rattlesnakes have gathered back at the den site. As temperatures drop the rattlers re-enter their den to spend another winter underground, another annual cycle completed.
Great Basin rattlesnakes are fascinating and beautiful animals. Their venomous bite, although rarely fatal & used only for feeding and defense, commands respect & common sense in their presence.
To avoid being bitten:
If you see a rattlesnake in your campsite contact a ranger. The chances of being bitten are EXTREMELY low. If however you are bitten by a rattlesnake:
DO NOT:
DO:
Take some time to learn about rattlesnakes and other reptiles. Perhaps if you are lucky you will see or hear one during your travels. Rattlesnakes are protected in national parks but often are not on other public lands. With some knowledge & understanding of the biology of rattlesnakes, you will know how to react when you encounter one of these remarkable animals.
Article written by: Bryan Hamilton, 2000
| Trail | Length | Elevation change | Description |
| Visitor Center Nature | .25 mi / 400 km | 80 ft / 25 m | Starts at Rhodes Cabins near the Visitor Center at Lehman Caves. Provides a leisurely walk in the pinyon-juniper forest and a look at the geology and ecology of the area. |
| Lehman Creek | 4.0 mi / 6.5 km | 2150 ft / 650 m | Located at Upper Lehman Creek Campground the trail climbs along Lehman Creek to the Wheeler Peak campground. This trail provides an alternative to the Scenic Drive as a link between the two campgrounds. |
| Big Wash | The two forks of Big Wash lead to remote wilderness in the southern half of the park. A maintained trail follows the South Fork along a narrow limestone gorge. An abandoned jeep trail serves as a route up the North Fork. The roads to Big Wash are not well marked, so ask for directions at the Visitor center and carry a map. | ||
| Lexington Arch | 1.0 mi / 1.6 km | 1000 ft / 300 m | This trail leads to Lexington Arch, a six-story limestone arch which is thought to be a now exposed section of cave passageway. Directions to the rugged dirt road that leads to the trailhead should be obtained at the visitor center. From beneath the arch, you get a wonderful view of the valley to the east. |
| Alpine Lakes Loop | 1.5 mi / 2.5 km | 400 ft / 120 m | This trail begins at Wheeler Peak Campground and forms a 3 mile (5 km) loop that passes both Stella and Teresa Lakes at elevations above 10,000 ft / 3048 m. It serves as an approach route to the Wheeler Peak Summit Trail and the Bristlecone Pine-Glacier Trail. |
| Wheeler Peak Summit | 5.0 mi / 8.0 km | 3000 ft / 910 m | Begin at the parking lot and horse loading ramp on the Wheeler Peak Scenic Drive approx. .5 mile / 1 km above Wheeler Peak Campground. The path to the summit of Wheeler Peak climbs steeply over rugged terrain. At 13,063 ft / 3,982 m, Wheeler Peak is the tallest mountain in the Great Basin National Park and the view is spectacular. Should be in good physical condition because of steepness and high elevation. |
| Bristlecone Pine Glacier | 3.0 mi / 5.0 km | 1000 ft / 300 m | This trail branches from the Alpine Lakes Loop Trail a short distance from Teresa Lake. Less than one mile / 1.6 km from the Alpine Lakes Loop, you enter the bristlecone forest. A short interpretive trail describes the bristlecones, which are some of the oldest things living on Earth. The trail continues to Wheeler Peak Cirque, where you will find the only permanent body of ice between the Sierra Nevada and Wasatch Range. |
| Bristlecone Pine | 2.8 mi / 4.6 km | 600 ft / 180 m | Interpretive signs in the bristlecone pine grove explain the lives and significance of these ancient trees. Ranger-guided hikes on this trail are offered daily in season. |
| Mountain View | 0.3 mi / 0.4 km | 80 ft - 25 m | This is a leisurely walk in the pinyon-juniper forest. The trail guide (available for loan at the visitor center desk) describes the geology and ecology of the area. The trail starts at the Rhodes Cabin next to the visitor center. |
| Osceola Ditch Trail | 0.3 mi / 0.4 km | 100 ft / 30 m | Begin at the signed pull-out on the Wheeler Peak Scenic Drive. Walk down slope through ponderosa pine, white fir and Douglas fir trees to the remnant of an 18 mile long channel built by gold miners in the 1880's. |
| Baker Creek | 7.0 mi / 10 km | 2,700 ft / 825 m | Two maintained trails begin at the trailhead at the end of Baker Creek Road. One leads up to Baker Creek Canyon to Baker Lake. From there it is a steep hike to Johnson Lake. The other trail follows the South Fork of Baker Creek to a high meadow. From there you can follow a trail that leads to Johnson Lake or complete the loop by following an unmaintained Timber Creek trail to the trailhead. |
| Johnson Lake | 5.0 mi / 8.0 km | 2600 ft / 800 m | Begins at Shoshone Campground at the end of Snake Creek Road. Climb through stands of aspens and evergreens along an old jeep road to Johnson Lake. Some places are neither marked or maintained. |
| South Fork Baker Creek / Johnson Lake | 11.2 mi / 18.2 km | 2,740 ft / 840 m | This trail splits off from the Baker Lake Trail and follows the South Fork of Baker Creek. It then joins with the Johnson Lake Trail, passing historic Johnson Lake Mine structures just before reaching the lake. |
| Baker Lake/ Johnson Lake Loop | 13.1 mi / 21.1 km | 3,290 ft / 1010 m | The Baker Lake and Johnson Lake Trails can be combined as a loop hike. The connecting section is a steep route over the ridge between Baker and Johnson Lakes. The ridgetop offers spectacular views in all directions, including the south faces of Wheeler Peak and Baker Peak. |
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Lehman Caves is a beautiful limestone cave with intriguing, unusual formations. Lehman Caves is one of the best places to see rare shield formations. Over 300 shields are known in Lehman Caves, more than any other cave. All of the cave is profusely decorated; stalactites, stalagmites, helictites, flowstone, popcorn, and other formations cover almost every surface of the cave.
Lehman Caves is a window into the past. Information about past surface climates are preserved in the layers of cave formations, while much can be learned about natural history from the "treasures" in old pack rat middens. Thus the cave has great potential for researchers to study both past climate change and the effects of climate change on plant and animal communities.
Water, geologic forces, and climatic changes combined to form Lehman Caves over a period of thousands to millions of years. Some cave formations are still actively forming today, others may restart in the future. Human activities in the cave and on the surface have the capability to affect Lehman Caves. Some scientists feel that there is an increase in pinyon pine and juniper trees in the South Snake Range due to fire suppression. This increase in trees would mean less moisture would make it down into the cave. Visitors on cave tours shed lint, skin, and hair. These unnatural additions to the cave change the ecosystem of the cave, and can affect the growth of formations. Development in the cave for tours, including two artificial tunnels and electric lights, also affect the cave.
Tours of Lehman Cave takes about 1.5 hours. It is a .75 mile walk on a paved trail with stairways and indirect lighting. Dress warmly, the cave is a constant 50� F all year round. Those under 16 must be accompanied by an adult.
Tours of Lehman Caves are scheduled daily. Closed Thanksgiving Day, Christmas Day, and New Year's Day. Children under the age of 2 being carried on the 60 Minute Tour are free. Children under the age of 5 are not permitted on the 90 Minute Tour.
All cave walks are limited to no more than 30 people. Tickets for cave tours may be purchased when you arrive in the park or by phone. Tickets may be purchased in advance by calling 775-234-7331 no more than 30 days prior to the day you wish to tour the cave. Advanced Sale tickets may NOT be made the day of your tour. Advance Sale Tickets must be paid for by Visa or Mastercard and there are no refunds. Golden Age and Golden Access passport holders must have card numbers when purchase is made in order to receive discount. Passport must also be presented when tickets are picked up.
Walk-in Tickets
Can only be purchased in person the day of the walk
At least 18 spaces available on each walk
Cash, Check, Visa, and Mastercard accepted
Advance Sale Tickets
Must be purchased at least 1 day in advance, but no more than 30 days in advance
Up to 12 spaces available on each
Payment must be made at time of purchase
No refunds or changes allowed after purchase
Visa or Mastercard required for phone reservations
School groups and bus tours must call at least two weeks in advance so special arrangements may be made if staffing permits.
Please call the park for current information on group sizes and teacher to student ratio requirements.
| 90 Min Tour | 60 Min Tour | First Room Tour - 30 Min | |
| Adult -12 & older | $ 8.00 | $ 6.00 | $ 2.00 |
| Child - 11 & younger | $ 4.00 | $ 3.00 | Free |
| Golden Age - (cardholder only) | $ 4.00 | $ 3.00 | $ 1.00 |
| Golden Access - (cardholder only) | 50% discount | 50% discount | 50% discount |
Basic Visit Recommendations
During snow season allow at least half a day to visit cave and explore visitor center. During summer allow at least a full day to explore the park, more if you enjoy hiking and exploring backcountry roads.
Wheeler Peak scenic drive opens and closes progressively with changes due to weather. It is always open for three miles to Upper Lehman Campground. There are many backcountry dirt roads available in summer months.
Geological Dates:
Archeological dates:
Historical dates:
Life in Lehman Caves survives in such an unusual environment by seizing every opportunity possible.
Bacteria lives in moist areas of the cave. This bacteria may be feeding on organic material that has seeped with the water through the "solid" rock. Some limestone caves have bacterial colonies that are chemoautotrophic, or "rock eating". These bacteria can derive all their necessary food and energy from rocks, minerals, or dissolved chemicals. They can form an ecosystem that is totally independent of the life-giving light from the sun. Research would be needed to determine if Lehman Caves is home to bacteria of this type.
Many animals that use the cave must leave to forage for food. These animals include chipmunks, mice, pack rats and bats. Chipmunks, mice and pack rats feed on vegetation. Plants do not grow in the dark cave environment. The bats in the Great Basin feed on flying insects, such as mosquitoes. They also must leave the cave to find adequate food. The nesting material brought into the cave and droppings left behind by these temporary residents is a major source of nourishment for animals that may live their entire lives in the cave.
Crickets, spiders, psuedoscorpions and the smaller mites and springtails can live their full life cycle in the cave. However, they are dependent on organic material packed in by other animals or washed in from the surface. They optimize meals that are often few and far between. Animals in the cave use a variety of senses to find needed shelter and food. Bats navigate through the pitch dark cave using echolocation. Pack rats follow the scent of their urine trail to return to their midden (nest). They will decorate these nests with pine cones, aluminum can tops, or anything else interesting, even though they can not see the decorations in the darkness. Touch is also very important. Pseudoscorpions use their elongated pinchers to feel the route in front of them.
Humans have unintentionally changed the ecology of Lehman Caves by introducing more food sources (wooden steps, lint, etc.), opening two new entrances, and installing electric lights. The lights, entrances, and tour groups slightly affect the temperature of the cave. Light in the previously dark cave allows plants to grow. These plants (mostly algae) are a source of food for animals. This can change what species live in the cave and how they interact.
Park rangers are trying to reduce our effect on the cave ecology. Lights are only turned on when a tour is in that area of the cave and visitors are not allowed to carry food or drink in the cave.
Life in the cave has dealt in the past with very slow changing conditions (constant temperature and near constant humidity), constant darkness, and uncertain food supply. Life in most caves has been poorly studied by scientists. Recently, they have found bacteria in caves that might have medical benefits or be a clue to the types of life NASA hopes to find during a future probe beneath the surface of Mars. It may benefit us to learn from the life styles of cave animals. The first step is to protect the conditions they live in, including the temperature, humidity, and limited sources of food available in Lehman Caves.
Water working slowly over the ages is the sculptor of Lehman Caves. The beginning of Lehman Caves can be traced back to approximately 600 million years ago, in the early Cambrian period. Much of what is now Nevada and western Utah was covered by a warm, shallow, inland sea.
During this time, many thick layers of sediment accumulated on the sea bottom. Some of the layers were composed of silt, some were sand, and still others were made up of a limy substance that originated from decomposed bodies of minute shell creatures. One of these limy layers was to become the marble in which Lehman Caves formed. This limy layer was compacted greatly by the weight of latter sediments deposited upon it. Under this pressure, the limy layer slowly turned to limestone rock. Later, as pressure and heat increased, the limestone turned to a low-grade marble.
Later, great forces under the earth's crust caused the layers of rock to buckle. This mountain range (the buckle) rose gradually until its peaks were thousands of feet above the valley floor. The rock layers cracked and fractured from the stresses of the uplift. In the future, the pattern of these fractures would help determine the floor plan of the cave.
Acidic ground water came from melting snow and rain. Pure water could not dissolve marble. This water absorbed carbon dioxide from the air and decaying vegetation in the soil, which generated carbonic acid. This weak acid dissolved out cavities in the marble bedrock. Eventually, the water level dropped, leaving air-filled passageways ready for the next stage of cave development.
Seeping water continues to enter the cave at a slow rate. The weak acid dissolves some of the bedrock above the cave and redeposits the mineral (calcite) on the floors, ceilings, and walls of Lehman Caves. Many of the beautiful formations in Lehman Caves are still growing, and are very fragile. Humans take care as they visit the caverns to enjoy, but not disrupt, the formations still changing by the act of water.
Geology of Lehman Caves written by Abigail Wines
Caves have drawn people since prehistoric times. For some, the draw was a belief in the supernatural. Caves figured into the religions of many ancient cultures. The Greeks went to caves for oracles. Many Olmec sculptures depict a priest coming out of an underground void. The Lakota believe that a cave in the Black Hills may be the place of creation. Today, cavers are drawn to caves by the mystery. The unknown in darkness ahead compels cavers to go ever deeper into caves. Scientists look to caves for their geologic secrets, unique biota, and reserves of information about natural history. For over a hundred years, people have been going deep into Lehman Caves and wondering at its secret mysteries.
Just what is a cave? A cave is a naturally occurring underground cavity. There are many different types of caves, including solution caves, tectonic caves, boulder caves, sea caves, and lava tubes. Tectonic caves tend to be relatively small and can form in almost any type of rock that has been highly fractured. Lava tubes are the fastest forming type of cave. They form as a flow of lava is running down an inclined surface. The surface of the lava flow cools from contact with the air and hardens to rock, while the inside keeps flowing. When the inside drains out, the result is a black tube of rock. Some caves may have ice in them seasonally, or year-round. Depending on the shape of a cave and its entrance, caves can trap cold air and contain permanent ice. Lava tubes can often be cold air traps. Solution caves, such as Lehman Caves, can have a great variety of formations and passage patterns.
Solution caves form in a rock that dissolves in acidic water. Limestone, dolomite, gypsum, salt, and marble are examples of rocks that form solution caves readily. The bedrock of Lehman Caves is low grade marble (it was only lightly metamorphosed), but it is usually referred to as limestone. The Pole Canyon Limestone was deposited under a shallow sea during the Cambrian Period (over 500 million years ago). Limey ooze and hard, calcium-rich, parts of sea life settled on the sea floor in a layer that was over 1,000 feet thick in some places. With time and pressure, these sediments solidified into limestone. Limestone is made of the mineral calcite, which is calcium carbonate in chemistry (CaCO3).
Caves in limestone form by the chemical dissolution of the rock. Water is always the agent for cave development. Very rarely does physical abrasion by gravel in moving water play a role in cave formation. Lehman Caves formed mostly by chemical means. The calcite in the limestone can dissolve in water if the water is at least weakly acidic. The acid at work in Lehman Caves was carbonic acid. Carbonic acid is familiar to all of us. It is in soda pop. Where did the acid come from?
The carbonic acid forms when water combines with carbon dioxide. The carbon dioxide might come from the air or from biological activity and decay of organic material (roots, leaves, etc.) in the soil. The carbon dioxide levels in air in soil can exceed 10%, which is 300 times higher than the carbon dioxide concentrations of the air we breathe. The acid-forming reaction is:
H2O + CO2 --> H2CO3 (carbonic acid)
The water and carbonic acid solution then seeps down into the limestone. The acid reacts with the calcite to dissolve it in the liquid.
CaCO3 + H2CO3 --> Ca+2 + 2(HCO3-) (calcium bicarbonate solution)
Many factors influence the amount of limestone that a body of water can dissolve. Temperature and carbon dioxide content are a few of the factors. Most dissolution of limestone happens in the aerated zone (vadose zone), where the acidic water first contacts the limestone. This is just below the soil zone. It does not form caves, but instead dissolves the rock from the top down. This can contribute to the karst topography that often characterizes limestone regions. Karst topography refers to land that has many sinkholes, caves, sinking streams, and limestone pillars. It is most often found in areas of soluble rock with a high rainfall. Some sinkholes are collapsed caves. The water that dissolves the top layer of rock may quickly be saturated with calcite. It may seem surprising that the same water can travel downward and dissolve more limestone to form caverns underground when it mixes with other water.
The next location of high dissolution of limestone is at, or just below, the top of the water table. This is the place where most caves form. There are three main reasons for this:
Because of these factors, cave passages will develop at about the level of the water table, or just below it, if the water table remains at a relatively constant height for a long time. This is why Lehman Caves is relatively level, even though the bedrock is inclined at a great angle.
Lehman Caves formed by this process of a weak carbonic acid dissolving away the rock. The groundwater was probably only slowly moving (no raging underground whirlpools), so the chemical processes completely formed the cave passages. Physical erosion, or scouring, did not play a role in the formation of Lehman Caves. No one knows how long it took the cave to form. Caves often tend to be in the range of hundreds of thousands to a few million years old. Lehman Caves is probably not more than a few million years old, at oldest. It is also not known when the water drained out of the cave. This could have happened because of uplift of the mountain range, climate change, and/or down-cutting of surface streams. Dating the cave, especially in relation to key regional geologic events, could shed some more light on the specifics of how the cave formed.
Yet even today the water seeping through the soil above the cave forms carbonic acid. The acidic water dissolves a little of the bedrock above the cave passages. Most of the limestone is dissolved at the boundary of the rock and soil. This probably does not weaken the cave substantially, until the surface wears down to intersect a cave passage, forming an entrance. The calcite stays in solution until the water reaches the air of the cave passage. At this point the water usually redeposits some or all of the calcite it contains in solution. The reasons for this vary slightly.
Degassing is one main cause of calcite deposition. The carbon dioxide content of the groundwater entering the cave passage is about 250 times higher than that of the air. So when the water contacts the air, it degasses just like a soda pop when you open it. Without the carbon dioxide, the calcite cannot stay in solution.
The chemical reaction reverses.- Ca+2 + 2(HCO3-) (in solution)--> CO2(gas) + H20(water) + CaCO3 (calcite)
The water continues on, but it does not carry as much calcite in solution. Another major method for deposition of calcite is evaporation of the water it is dissolved in.
Either way, calcite is deposited. Depending on what shape the calcite takes, it may be called by different names. Travertine is one name for the calcite in the cave. Dripstone is a generic caver term that encompasses any cave decoration caused by dripping, splashing, or seeping water. Speleothems are cave decorations formed after the cave passage has formed, such as dripstone. (Speleogens are features like scallops that form in the bedrock while the cave is forming.)
People often want to know how old the formations are. Broken columns have growth rings that look like tree rings, but there might be thousands of years between each period of deposition. It is not possible to count the rings to date a stalactite. Formations in Lehman Caves have not been dated, so we can only guess by observing the current growth rates. Yet these current rates may not be at all similar to growth rates in the past. Soda straw stalactites that are growing on broken formations in Lehman Caves are mostly less than an inch long. Most of these formations were broken between 1885 and 1922, or roughly a century ago. Keep in mind that because soda straws are hollow, they grow longer much faster than wider speleothems do. The same amount of calcite may be deposited per year on other formations, but the change would not be as noticeable if it is spread over a greater surface area (i.e. flowstone or large columns). Growth rates vary depending on the amount of calcite in solution and the drip rate. Size can be misleading. The largest column in the cave may be younger than a two-inch long soda straw. Conditions can be very localized. Water can change the path it follows into the cave, so formations that are dry may someday be wet again. The amount of water dripping into Lehman Caves now does not seem to account for the large formations in rooms like the Gothic and Grand Palaces. Many formations now are dormant and probably grew more in the past when the climate was wetter, possibly during the Ice Ages.
When water seeps into the cave and drips from the ceiling, a stalactite is the result. The first stage is a soda straw stalactite. These are hollow. The water drop travels down the central canal of the soda straw and hangs on the end, depositing more calcite before dropping to the floor. When the hollow tube eventually plugs up, more water runs on the outside of the stalactite, making it thicker and forming a stalactite. Yet there is still some water moving internally through stalactites (hence the helictites that form on some and the recrystallization of the internal portions). If the drop of water that falls still contains calcite when it hits the ground, this may deposit as well to form a stalagmite. They tend to be squatter than stalactites. The longer the water drop hangs from the ceiling, the less likely it is to still contain calcite when it lands on the floor. Not all stalactites have stalagmites beneath them. Columns result when a stalactite and stalagmite join.
The horizontal ridges that developed on some formations in the cave, such as the stalactites over the path in the Grand Palace, are called crennulations. Crennulations tend to have a wavelength of about 1 cm, no matter what material they develop in. They are common on icicles as well. One theory says that they begin when water flows over a slight bump in the surface. The water film thins as it passes the bump, which increases evaporation and/or carbon dioxide loss. More calcite is deposited on the bump. Just below the bump the water pools up again, and below this small pool the water thins again due to surface tension, depositing more calcite to form another ridge. The whole cycle starts over again. Crennulations seem to be self-perpetuating below the initial bump. Microgours in flowstone and the saw-tooth edge of some draperies may also be self-perpetuating in the same way.
Draperies form when calcite-rich water runs down an overhanging wall. Draperies that are striped from varying amounts of impurities are also called cave bacon.
Flowstone forms if there is a thin film of water flowing down a sloping surface. The calcite is deposited layer upon layer, like coats of paint.
Cave popcorn (also called cave grapes or corraloids) is a catchall term describing a small, bumpy speleothem that usually does not have a central conduit, unlike stalactites. Although these formations are given the same name, they can form in very different ways depending on the location in the cave. Popcorn can be deposited on the walls of a standing pool of water (like on the rimstone dams in the Cypress Swamp and the small hollow along the West Room path). Most of the popcorn in Lehman Caves was not formed under water, however. Other ways popcorn can form is by a thin film of water flowing over an irregular surface, splashing water, and by water seeping through the bedrock. The seepage method is probably predominant at Lehman Caves. The water "sweats" through the wall and the crystals of the popcorn. The water then evaporates, or sometimes drips, and leaves calcite deposits.
Wall coating forms in a similar way to popcorn. It forms by water seeping from the bedrock and depositing calcite. The result is a calcite crust covering the wall.
Rimstone dams are located in the Cypress Swamp and in the Lodge Room. When active, each dam would hold a small pool of water behind it. Water flowing over the top of the dam deposits more calcite, increasing the height of the dam. They can grow much larger in some caves, up to a height of over 40 feet! Some of the formations (especially flowstone) in Lehman Caves also have a much smaller variation of rimstone dams on their surface, called microgours. These can look like tiny terraces in the flowstone or just like bumps. They build up as a thin film of water on the formation flows over irregularities on the surface.
Helictites are intriguing formations because they grow at all sorts of angles, seemingly defying gravity. They have a central tube that water passes through during their growth, but this tube is on a microscopic scale (0.008 to 0.5 mm in diameter). They form by seeping, capillary water, rather than by dripping water. It is unusual to see drops of water on the ends of helictites. Helictites originate at a very small hole in the side of a formation (like a column or soda straw) or in the calcite coating on a wall. The hole is small enough that water moves because of capillary action (water will rise through a small tube) or hydrostatic pressure rather than because of gravity. This explains why helictites do not grow straight down, but it does not explain why they curl and twist. This may be caused either by impurities or by the way the wedge-shaped calcite crystals stack upon each other. In some areas, particularly the West Room, there are a different variety of helictites, known as butterfly helictites.
Shields are the formation that Lehman Caves is best known for. They are not as rare as was once thought, and have been found in at least 80 caves in the United States. Caves that have shields often have them in large numbers. Lehman Caves has an unusually large concentration of shields, more than 300. Shields consist of two round or oval parallel plates with a thin medial crack between them. The medial crack is thought to be an important clue to their formation. Shields tend to form in caves with highly fractured limestone (like Lehman). Shields grow at all sorts of angles from the ceiling, wall, and floor of the cave. The most accepted theory for how shields form relates to fractures in the bedrock. Water under hydrostatic pressure moves through thin fractures in the limestone. As it enters the cave passage by means of capillary action, the water deposits calcite on either side of the crack, building plates of calcite with a thin, water-filled crack between them. Shields may be decorated with popcorn or helictites on the top and along the medial crack, and draperies and stalactites on the bottom. Sometimes the speleothems on the bottom plate get too heavy and pull the shield apart.
Welts are thought to be similar to shields. They are like scars of calcite. They grow along a fracture in the bedrock or in a speleothem that is opening very slowly. A sudden break will not form a welt. A column may pull apart because of settling of underlying sediment. As the crack grows, water seeps out and deposits calcite.
Some researchers believe that bulbous stalactites are related to shields and welts, but it is not known exactly how. Some researchers believe that turnip-shaped bulbous stalactites may be only a variation of a welt or shield. It has been observed that caves with this shape bulbous stalactites also have shields and welts, so there may be a connection. Another theory for the origin of bulbous stalactites has to do with intermittent flow of water. Usually, a growing soda straw stalactite has water flowing both internally and externally. If the internal flow stops, calcite may plug the internal channel. Then when the internal flow resumes, the internal pressure may cause the stalactite to rupture. If the water oozes out in small quantities, helictites form. If there is more water, a bulbous form results. However, no one really knows the real method that bulbous stalactites form by.
Soda straws in the Lodge Room area have been observed with bubbles on their tips during wet periods in early spring. Bubble-blowing stalactites are thought to be caused when internal flow in a soda straw is temporarily interrupted while external flow continues. This can draw water and air into the straw. When internal flow resumes, the result will be a bubble on the end of the soda straw with water dripping from the bubble. This theory of intermittent flow sounds similar to the one stated above for bulbous stalactites. Yet if this theory is correct, why the apparent correlation between bulbous stalactites and shields?
Moonmilk is a white formation that looks like powder when dry or cottage cheese when wet. There is a lot of it in the Rocky Road and on the ceiling in the Inscription Room. Moonmilk can be a combination of different (mostly carbonate) minerals. Some common minerals composing moonmilk are calcite, aragonite and hydromagnesite. Humans have used moonmilk as medicine to stop bleeding, induce a mother's milk, and for ulcers. There are several theories for moonmilk. One is that bacteria play a role in its origins. Another is that the moonmilk is deposited directly from water the same way other speleothems are, but for some reason the crystals never grow large or connected.
Gypsum formations form in a similar way to calcite speleothems. Gypsum is a mineral, with the chemical formula CaSO4� 2H2O. Basically, it is calcium sulfate with some water attached. Gypsum can take forms known by cavers as snow, flowers, crust, needles, and hairs, depending on the shape. There are no gypsum formations along the tour route, but there are many in the Gypsum Annex. They tend to be white (or colorless), small, and very fragile.
Calcite in its pure form is colorless, yet most of the speleothems in Lehman Caves are colored. The color comes from impurities in the calcite. White color can be caused by inclusions of water. Most of the brown to yellow to red color in the cave is caused by iron oxides (natural rust) or organics. One exception to this is the orange-pink color on the ceiling in the Inscription Room, which is caused by a bacteria, but no one knows what type.
Some of the formations in Lehman Caves have been redissolved. A good example of this is the Eagle�s Wing in the Lodge Room. The cave drained and some formations grew, then the cave refilled with water some time later. This water dissolved part of the formations. The water drained again, and decoration of the cave continued. It is also possible that some dissolution of formations happens in the air. The moisture in the air that condenses on formations and the bedrock may be able to dissolve some calcite. This is most apparent with draperies. Draperies can look heavily corroded and have holes in them. Draperies have a high surface area for water to condense onto and are very thin, so even a small amount of dissolution would be very noticeable. Some researchers believe that bacteria may play a role in condensation corrosion.
Flowing water caused the scalloping in some parts of the cave. The water (with a little acid in it) moved past the wall from the gradually inclined side towards the steep side of the scallop. As the water moved over the ridge, it swirled down on the backside of the scallop, enlarging it. The erosion was caused by acid in the water, not gravel and particles. It is possible to determine the speed of the water by measuring the length of the sides and the angle between them. The direction is determined by the steep and gradual sides. The steep side in each pocket is upstream (in other words, on the downstream side of the ridge). It is possible to map flow direction in a cave using the scallops. In Lehman Caves, there are places where the scallops in the same room indicate different flow directions. There were probably eddies off the main flow that caused this. The path of the water was generally from the Grand Palace towards the exit.
Some features in caves show definite directional characteristics. A good example in Lehman Caves is the directional popcorn found in the West Room and Inscription Room. Only one side of the formations has popcorn, while the other side is undecorated. This is probably because as water moved through the cave, it deposited the popcorn in the eddy behind the formations. It is also possible that this may have happened in an air-filled passage by similar means.
Speleologists have theorized that at one time there may have been rising warm or hot water in the cave. This water would only need to be at least 1� warmer than the water in the cave to make a difference chemically. In some places, especially in the Rocky Road, there are ceiling half tubes. These are felt to be places where warmer water entered the cave. The other evidence is the increased metamorphism of the marble along the Rocky Road fault. Not much research has been done to test this theory. Cracks in the bedrock (joints or faults) have been a major avenue for water (warm or cool) to enter the cave.
The location of faults controlled some of the cave passages. Cave passages tend to follow a fault for a short distance, then go off of it. Faults may be open or closed, meaning there may be space between the moving walls or not. Cave passages may develop along open faults because there is a space for the water to enter. If a fault is only open for a short distance, a cave passage may develop in that section, but the passage will not extend into the closed section of the fault. The Rocky Road, the Music Room, and the Royal Gorge (passage between Sunken Gardens and Talus Room) are examples of passages that developed along faults.
Any mention of faults usually results in questions about earthquakes. It does not seem that the faults in the cave have been active for a long time. If there were movement along one of them, it would probably cause some shifting in the cave. Earthquakes generated by movement along faults further away don�t seem to cause damage in the cave, even when they shake the surface. Earthquakes generate three different types of waves, which travel in different ways. The undulating motion waves travel along the surface and can cause a lot of damage. Sound waves generated by earthquakes can travel at deeper depths. It is sometimes possible to hear an earthquake while in a cave. The shear number of formations in Lehman Caves (and the size of the formations in the Gothic and Grand Palaces) is evidence that not much shifting has happened in most of the cave for a long time. The one exception is the Talus Room.
The rockfalls in the Talus Room may or may not have been triggered by earthquakes. Most collapse in caves happens either when the water first drains out of the cave or when the surface finally erodes to close to the roof of the cave. Not much has happened to weaken the strength of the bedrock since the water table lowered. Yet the water that filled the cave was also giving a little support for the weight of the ceiling. The Talus Room probably started to collapse when the water drained from the cave. It has not reached a stable point yet, probably because of the room�s size, although the fault zones have played a role as well. There are probably old cave passages buried beneath the rubble in the Talus Room.
There is airflow at the "ends" of the cave, beyond the Talus Room. Airflow in Lehman Caves is caused by a chimney effect, air moving between entrances. However, the air may be travelling through very small cracks and vents explorers would never be able to fit through.
Weather in caves tends to be very consistent, compared to the surface conditions. Lehman Caves is 50� F year round. The relative humidity varies between 90 and 100%. The closer a room is to an entrance, the more variation in temperature and humidity it will have. Most sizeable caves do have a nearly constant temperature. The airflow is not sufficient to change the temperature of the cave. Air entering the cave is either warmed or cooled by contact with the bedrock in the cave. The temperature of the bedrock controls the temperature of the air in the cave. The temperature of the bedrock is often just about the average surface temperature. Seasonal temperatur variations at the surface do not affect the bedrock at the depth of most caves.
The near-constant conditions in many caves is the main reason that change can be very slow in some caves. There are few large animals entering the passages in Lehman Caves. There are no rivers. It never rains. Airflow at its strongest is a slight breeze. Most of the cave is too deep to be invaded and changed by plant roots. The speleothems grow on a time scale that is difficult for humans to observe. This means that changes humans cause in caves will last much longer than might be expected by extrapolating from surface conditions. Footprints may last for centuries.
Lehman Caves present an interesting geologic puzzle. The geologists believe that they have figured out many of the mysteries of the cave, but there are many more questions to answer. There is a bacteria in the cave that should be studied, along with potential bacterial causes of moonmilk, colorations, and condensation corrosion. A paleonotological dig, especially in the Lost River Passage, could turn up some very interesting results and could help determine if and when there might have been another entrance in that part of the cave. Shields and bulbous stalactites are not well enough understood. The Gypsum Annex is an interesting part of the cave because it is so incredibly different from the main cave. Why? It might be possible to learn more about past climatic information by studying the speleothems. Many opportunities for discovery and learning are still in Lehman Caves. The mysteries continue, and the answers to these questions will only lead us to more questions.
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Great Basin National Park offers good fishing possibilities for anglers of all ages and experience. Two of the five lakes and three creeks contain fish. You will find Lahonton cutthroat trout in Baker Lake. Johnson Lake has brook trout. There is rainbow trout in the Snake and Lehman Creeks and Baker Creek has both rainbow and brown trout.
The high elevation (above 10,000 feet) allows ice free conditions only from June through September. Dense brush along the creeks can sometimes cause an access problem. The high elevation can also bring highly variable weather conditions. Be sure to boil all drinking water.
The use of live bait, amphibians or non-preserved fish eggs or fish roe and/ or chumming in park waters is prohibited. Fish entrails are not to be returned to the water. All lakes and rivers are closed to floatation devices. Some access roads may be closed from October to May. A Nevada fishing license with trout stamp is required in the park.
Great Basin National Park offers several fishing possibilities. Five different kinds of trout occur in the park: Bonneville cutthroat trout, Lahontan cutthroat, rainbow, brook, and brown. Of these only the Bonneville cutthroat is native.
There are self sustaining populations of trout in Johnson and Baker Lakes and in Lehman, Baker, Snake, Strawberry, Williams, Ridge, Pine and Shingle Creeks in Great Basin National Park. In Stella, Teresa, Brown and Dead Lakes there are no fish because of low late-season water levels and winter kill. Very few fish are found above 8,000 feet.
Access to these areas is sometimes a problem. High elevation may allow ice- free conditions only from June through September. Some access roads may be closed seasonally. To get to many of these locations a moderate to strenuous hike may be necessary, ask a ranger for details. Be prepared for all types of weather at higher elevations; weather conditions may change rapidly. Dense brush along the creeks may sometimes cause access problems. The most easily accessed fishing spots are along Lehman, Baker, Strawberry, and Snake Creeks. Finding parking can be difficult for Lehman Creek.
To legally fish in Great Basin National Park you need a Nevada state fishing license for anyone twelve and older. A trout stamp is required for annual license but not for a temporary license. A fishing license can be obtained at T & D's in Baker. The limit is ten (10) trout per person per day, with no size restrictions. Fishing is allowed anytime day or night. Worms and nightcrawlers are permitted, but digging for worms is not allowed in the park boundaries. The use of other live bait, amphibians or non-preserved fish eggs or roe and / or chumming in the park is prohibited. Fish entrails are not to be returned to the water. All lakes and rivers are closed to flotation devices. Transporting fish from one body of water to another is prohibited. Fishing by means other than rod and reel is prohibited.
Other places to fish outside the park are Cave Lake State Park, approximately 50 miles west of the park just off US 6 & 50. Here you can lake fish, boat, camp, and picnic. For more information on Cave Lake State Park contact:
Nevada Division of State Parks
Capitol Complex
Carson City, NV 89710
Phone: 775-728-4467
Pruess Lake, 20 mile south of Baker, has catfish and other warm water species. A Utah state-fishing license is required. For more information about getting a license write to:
Utah Wildlife Resource Division, Southern Regional Office
622 N Main St
Cedar City, UT 84720
Phone: 435-586-2455
For additional fishing information contact:
Nevada Department of Wildlife
1080 N Airport Rd
Ely, NV 89301
Phone: 775-289-1655
The Bonneville cutthroat trout is the only fish native to Great Basin National Park. Other trout species (Lahonton cutthroat, rainbow, brook and brown) have been stocked in the lakes and streams of the South Snake Range until 1986. The Bonneville cutthroat trout arrived in the mountain waters naturally, and was isolated there by changing climatic conditions. Unfortunately, the introduced fish species are a threat to the survival of the Bonneville cutthroat trout.
Thousands of years ago, an immense lake occupied the bottom of Snake Valley. This was only an arm of the ancient Lake Bonneville, which encompased what is now the Great Salt Lake in Utah. Ancestors of the current Bonneville cutthroat trout lived in this lake. With the end of the ice ages, the climate in the Great Basin slowly warmed and dried. As the lake slowly shrank down to the size of the current Great Salt Lake and increased in salinity, the fish took refuge in the streams of the bordering mountain ranges.
These mountain streams were isolated from each other. This meant that if a population of these fish in one stream died off for any reason, there was no way for fish to migrate from another stream's population.
Most of the streams on the eastern side of the South Snake Range had healthy populations of Bonneville cutthroat trout at the time the settlers arrived. They transplanted Bonneville cutthroat trout from steams on the east side to fishless streams on the west side of the mountain range as a source of food.
Decades later, other fish species were transported to the South Snake Range and planted in the mountain lakes and streams. These species outcompeted and/or interbreed with the native fish. Some of the park's streams no longer have any of the native Bonneville cutthroat trout. Others contain only Bonneville/rainbow trout hybrids.
Great Basin National Park is charged with a mission to provide for public enjoyment of the park AND to protect the park's natural resources. The park started a long-term project in 1999 to eliminate the nonnative fish from certain park streams and return the native Bonneville cutthroat trout to the habitat.
Reintroducing Bonneville Cutthroat Trout
The Bonneville cutthroat trout is the only trout native to Great Basin National Park and East Central Nevada. The species was abundant in Lake Bonneville 16,000 to 18,000 years ago. The Snake Valley contained an arm of this lake. As the climate changed and the lake level dropped, the trout migrated into the higher mountain streams where they eventually became trapped.
Unfortunately Bonneville cutthroat trout were extirpated from their ancestral waters within Great Basin National Park largely as a result of two factors: stocking of nonnative fish and habitat degradation from human activities. Indiscriminate and widespread stocking of nonnative brook, brown, and rainbow trout introduced overwhelming competition for food and other resources. In addition, rainbow trout interbreed with native cutthroats and reduce species purity. Tens of thousands of nonnative trout were stocked into streams of the South Snake Range before designation of Great Basin National Park.
Water diversions, mining, and domestic livestock grazing significantly altered the streams by reducing streamflows, increasing sediment, and decreasing streamside cover. In recent years, land use has changed within the park. Park streams and lakes are no longer stocked with nonnative trout, mining and livestock grazing no longer occur, and stream habitat is improving.
Great Basin National Park currently contains two small streams of Bonneville cutthroat trout. One stream on the western side of the park contains native fish that were stocked outside of their historic range around the turn of the century. A remnant population was discovered just last year on the east side of the park. Bonneville cutthroat trout
Great Basin National Park, in cooperation with Trout Unlimited, the U.S. Fish and Wildlife Service, Nevada Division of Wildlife, the Ely District Bureau of Land Management, and the Humboldt-Toiyabe National Forest, is working to restore the Bonneville cutthroat trout to approximately eighteen stream miles within the South Snake Range.
Six streams within the park are being considered for reintroduction efforts. The full Bonneville cutthroat trout reintroduction program is expected to take six to ten years to complete. The first step, to survey the selected streams to document existing baseline conditions, is currently underway. The first streams slated for study and reintroduction are Strawberry Creek, Mill Creek, and the South Fork of Big Wash. Upper Snake Creek, the South Fork of Baker Creek, and Upper Lehman Creek will follow.
When the new populations have stabilized, recreational fishing for this unique species will greatly add to visitor enjoyment of the park. Bonneville cutthroat in their native waters can reach relatively large sizes in small creeks compared to brook, rainbow and brown trout.
In order to make this project a success, the park asks that you please do not move any fish between bodies of water within the park. While fishing in those streams that contain populations of Bonneville cutthroat trout, please practice catch and release techniques using barbless hooks and fill out an angler survey card before you leave.
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