Owens Valley*

Owens Valley happens to be one of the most singular and interesting places in the United States. It is located in the western part of the continent – between the Sierra Nevada and the Inyo Mountains. This valley forms part of the geomorphic province of Basin and Range, characterized by mountains and valleys as unique features resulting from the process of Earth crust movement.

Geomorphology: The Shape of the Land

The Owens Valley lies within crust of the Basin and Range province, which is famous for its “horst and graben” structure. Consider the crust of the earth to be rifting apart: the surface breaks, and some blocks go down while others rise up. This process forms a pattern of highs and lows. Owens Valley is one of these low areas, known as a “graben,” while surrounding mountains are the high areas known as “horsts.” The elevation of the valley varies from about 3000 to 6000 feet and includes flat and gently sloping areas.

Erosion, the wearing away of rocks and soil by water and wind, and deposition combine in the process whereby these materials are laid down in new places. Through such continuous action, an alluvial fan—the fan-shaped deposit of soil and rocks at the base of the mountains—and a basin fill, or a layering of sediments on the floor of the valley, form over time.

Soil and Vegetation: Life on the Land

Soils in Owens Valley vary considerably. On the alluvial fans, Torrifluvents and Torriorthents soils are well drained and support a wide variety of plant life. Elsewhere in the basin-fill areas, the soils may be poorly drained and these areas may support different kinds of plants. There is even dune sand in places!

The vegetation of Owens Valley differs according to soil and location. You might find plants such as saltbush and greasewood that are tolerated on salty soils in the areas of basin fill. On the alluvial fans, there were plants like shadscale and hop-sage that could stand the drier conditions. Higher up on the fans, there is black bush with sagebrush. South of Owens Lake, creosote bush is the predominant plant.

Climate: Hot and Dry

Long-term temperatures and rainfall—Owens Valley has a hot and dry climate. Average annual precipitation, or the amount of rain that falls in an average year, is only about 4 to 8 inches. Most of this rain falls during the winter months. The mean annual temperature varies from 55° to 65° F. Because it is so dry, plants and animals must be tough in order to survive with little water.

Water: The Lifeline

Water plays a major role in the Owens Valley way of life. Along the middle of this long valley runs the Owens River, which furnishes water to many plants, animals, and people. Centuries ago, Owens Lake used to overflow periodically and send water to the neighboring valleys. Nowadays, so much of the Owens River water is exported to Los Angeles that Owens Lake is virtually dry.


Owens Valley is a place both fascinating in geology and ecology. Distinct landform, variety of soils, and flora hardiness testify to the ability of life to adapt to the rigors of heat and dryness. Understanding Owens Valley would help us recognize the sensitive links between land, water, plants, and animals that give this part of the world its special identity.


Comparative Geomorphology

Here’s a comparison between the geomorphology of the Funeral Mountains – Greenwater Valley subsection and the second geomorphological description:

Funeral Mountains and Greenwater Valley

  • Landforms: Steep to very steep mountains and valleys, with very gently to moderately sloping alluvial fans, nearly level basin floors, and dry lake beds.
  • Orientation: Mountains align north-south or north-northwest.
  • Elevation Range: About 1,000 feet to 6,703 feet on Pyramid Peak, with many peaks over 5,000 feet.
  • Geomorphic Processes: Mass wasting, fluvial erosion and deposition, and eolian deflation and deposition.


Geomorphology is the scientific study of landforms and the processes that shape them, including their origin, evolution, and spatial distribution.

Lucerne and Johnson Valleys

  • Landforms: Steep mountains, moderately steep hills, gently to moderately sloping pediments and alluvial fans, nearly level basin floors, and dry lake beds. Presence of “badlands” on eroded Miocene nonmarine sedimentary rocks.
  • Orientation: The hills’ general orientation is less straightforward than the major faults, which trend northwest.
  • Elevation Range: About 1,600 feet up to 4,873 feet in the Granite Mountains, 5,525 feet in the West Ord Mountains, 6,309 feet in the East Ord Mountains, and 5,878 feet in the Rodman Mountains.
  • Dry Lake Beds: Includes Lucerne, Soggy, Melville, Galway, Emerson, and Deadman Lake.
  • Geomorphic Processes: Mass wasting, fluvial erosion and deposition, and eolian deflation and deposition.
Greenwater Valley, Death Valley National Park


  • Landforms: Both regions feature steep mountains and valleys, alluvial fans, basin floors, and dry lake beds. However, the second description includes pediments and mentions “badlands,” which are not noted in the Funeral Mountains – Greenwater Valley description.
  • Orientation: The Funeral Mountains – Greenwater Valley mountains align north-south or north-northwest, while the hills in the second description have a less clear orientation than the major northwest-trending faults.
  • Elevation Range: The Funeral Mountains – Greenwater Valley has a broader elevation range, reaching higher peaks (up to 6,703 feet), whereas the second area reaches 6,309 feet in the East Ord Mountains.
  • Dry Lake Beds: The second description specifies several large dry lake beds by name, which are not mentioned in the Funeral Mountains – Greenwater Valley description.
  • Geomorphic Processes: Both regions experience similar geomorphic processes, including mass wasting, fluvial erosion and deposition, and eolian deflation and deposition.

In summary, while both regions share common geomorphic features and processes, they differ in specific landform characteristics, elevation ranges, and the presence of features such as “badlands” and named dry lake beds.

Geologic Diversity

When someone mentions they are a geologist, it’s easy to assume that all geologists do the same thing. However, geology is a diverse and multifaceted field, encompassing a wide range of specialties. Each geologist may focus on different aspects of the Earth’s structure, materials, processes, and history. Here’s a more detailed look at the various types of geology and the distinct roles that geologists might have:

Types of Geology

  1. Structural Geology: Geologists in this field study the architecture and processes responsible for the deformation of the Earth’s crust. They analyze faults, folds, and rock formations to understand tectonic movements and stress patterns.
  2. Petrology: Petrologists examine the origin, composition, and structure of rocks. They specialize in:
    • Igneous Petrology: Focuses on rocks formed from magma or lava.
    • Sedimentary Petrology: Studies rocks formed by the accumulation of sediments.
    • Metamorphic Petrology: Investigates rocks transformed by heat and pressure.
  3. Mineralogy: Mineralogists study minerals, including their structure, properties, classification, and distribution. They identify and analyze mineral compositions in various geological contexts.
  4. Geochemistry: Geochemists explore the chemical composition of Earth materials and the chemical processes occurring within and on the Earth’s surface. They study element cycles and mineral interactions.
  5. Geomorphology: Geomorphologists study landforms and the processes that shape them. They analyze erosion, weathering, and sediment deposition to understand landscape evolution.
  6. Sedimentology: Sedimentologists focus on sediments and sedimentary rocks, including their formation, transport, and deposition. They study sedimentary environments like rivers, lakes, and oceans.
  7. Paleontology: Paleontologists study fossils and ancient life forms to understand the history of life on Earth. They analyze fossil records to reconstruct past ecosystems and evolutionary trends.
  8. Volcanology: Volcanologists study volcanoes, volcanic processes, and volcanic rocks. They monitor volcanic activity and assess eruption risks.
  9. Seismology: Seismologists study earthquakes and the propagation of seismic waves through the Earth. They analyze seismic data to understand earthquake mechanics and predict future events.
  10. Geophysics: Geophysicists use physical methods to study the Earth’s interior and its physical properties. They specialize in:
    • Seismic Geophysics: Uses seismic waves to map the Earth’s interior.
    • Magnetic Geophysics: Studies the Earth’s magnetic field and anomalies.
    • Gravitational Geophysics: Examines variations in the Earth’s gravitational field.
  11. Hydrogeology: Hydrogeologists study groundwater, its distribution, movement, and quality. They analyze aquifers and manage water resources.
  12. Engineering Geology: Engineering geologists apply geological knowledge to construction and environmental management engineering practices. They assess ground stability and risks for infrastructure projects.
  13. Environmental Geology: Environmental geologists focus on human interaction and the geological environment. They address natural hazards and resource management to mitigate environmental impacts.
  14. Economic Geology: Economic geologists study materials for financial and industrial purposes, such as minerals, oil, and gas. They explore and develop natural resources.
  15. Planetary Geology: Planetary geologists study the geology of other celestial bodies, such as moons, planets, and asteroids. They analyze surface features and geological processes beyond Earth.

Each type of geologist brings unique expertise to their field, contributing to a comprehensive understanding of the Earth’s dynamic systems. Understanding these distinctions helps us appreciate geologists’ specialized skills and knowledge of various challenges and projects.


Geology is a diverse field with various specialties. Structural geologists study Earth’s crust deformation, while petrologists focus on rock origins and types. Mineralogists analyze minerals, and geochemists explore Earth’s chemical processes. Geomorphologists study landforms, sedimentologists examine sediments, and paleontologists investigate fossils. Volcanologists monitor volcanic activity, seismologists study earthquakes, and geophysicists use physical methods to probe Earth’s interior. Hydrogeologists focus on groundwater, engineering geologists apply geology to construction, and environmental geologists manage natural hazards. Economic geologists explore resources like minerals and oil, and planetary geologists study celestial bodies. Each specialty offers unique insights into Earth’s processes and history.

Dune Saltation

Dune saltation is a key process in the formation and movement of dunes. It involves the hopping or bouncing movement of sand grains across the surface, driven by wind. Here’s a detailed explanation:

Dune Saltation Process

  1. Initiation: Wind speeds reach a threshold where they can lift sand grains from the ground. This threshold varies depending on the size and weight of the grains, as well as the wind speed and direction.
  2. Lift-off: Sand grains are lifted into the air by the wind. The initial lift is usually caused by the impact of other grains, which creates a chain reaction.
  3. Transport: Once airborne, the grains are carried by the wind. They travel a short distance before falling back to the ground due to gravity.
  4. Impact: When the grains land, they can dislodge other grains, causing them to lift off and continue the saltation process. This impact also leads to the erosion and smoothening of the surface.
  5. Repetition: The cycle of lift-off, transport, and impact continues, causing the sand grains to move in a series of short hops or bounces.

Factors Influencing Saltation

  • Wind Speed: Higher wind speeds increase the distance and height of saltation.
  • Grain Size: Smaller grains are more easily lifted and carried by the wind, while larger grains require stronger winds.
  • Surface Conditions: Smooth surfaces allow for easier saltation, while rough surfaces can trap grains and reduce movement.
  • Moisture: Moisture in the sand can cause grains to stick together, inhibiting saltation.

Impact on Dune Formation

  • Dune Shape: Saltation contributes to the growth and movement of dunes. The continuous movement of sand grains causes dunes to migrate toward the prevailing wind.
  • Sorting of Grains: Saltation can lead to sorting grains by size, transporting finer grains further than coarser ones.
  • Erosion and Deposition: Saltation causes erosion and deposition, shaping the landscape and forming various dune structures, such as crescent-shaped barchan and linear dunes.

Understanding dune saltation is crucial for studying desert geomorphology and predicting changes in dune landscapes.

Dune saltation is the wind-driven process where sand grains are lifted, transported, and deposited in a series of hops. Wind lifts grains into the air, which then travel short distances before falling back, dislodging other grains upon impact. This cycle causes sand to move and shapes dunes. Wind speed, grain size, surface conditions, and moisture influence saltation. Higher wind speeds and smaller grains increase movement, while moisture and rough surfaces reduce it. Saltation contributes to dune formation, migration, and sorting of grains by size, playing a crucial role in desert geomorphology.

#6 – Trona Pinnacles: A Unique Geological Wonderland


The Trona Pinnacles, located in the California Desert National Conservation Area near the town of Trona, offer a striking landscape of unusual tufa formations rising dramatically from the desert floor. Here’s an expanded look at what makes the Trona Pinnacles a popular destination:

Geological Significance

  • Formation: The Trona Pinnacles are composed of tufa, a type of limestone that forms in alkaline lake waters. These formations were created 10,000 and 100,000 years ago when the area was submerged under the prehistoric Searles Lake.
  • Structure: The site features over 500 pinnacles, ranging from small spires to large towers that reach up to 140 feet. These formations vary in shape and size, creating a surreal and otherworldly landscape.

Attractions and Activities

  1. Exploring the Pinnacles:
    • Self-Guided Tours: Visitors can explore the pinnacles at their own pace, walking among the formations and marveling at their unique shapes and textures. The area is open for hiking and offers numerous trails and pathways.
    • Interpretive Signs: Informational signs throughout the site provide insights into the geological history of the pinnacles, explaining how they were formed and their significance.
  2. Photography:
    • Landscape Photography: The Trona Pinnacles are a favorite subject for photographers due to their striking appearance and the dramatic contrasts between the tufa towers and the surrounding desert. The light at sunrise and sunset casts a magical glow on the formations, enhancing their visual appeal.
    • Astrophotography: The remote location and dark skies make the Trona Pinnacles an excellent spot for stargazing and astrophotography. The formations provide unique foregrounds for night sky photography, including stunning views of the Milky Way.
  3. Off-Roading and Vehicle Access:
    • Off-Road Trails: The area around the Trona Pinnacles is accessible by dirt roads suitable for high-clearance and four-wheel-drive vehicles. Off-road enthusiasts can enjoy exploring the rugged terrain and discovering hidden viewpoints.
    • Scenic Drives: For those who prefer a more leisurely visit, scenic drives through the area offer beautiful views of the pinnacles and the surrounding desert landscape.
  4. Camping:
    • Primitive Camping: The Bureau of Land Management (BLM) allows primitive camping near the Trona Pinnacles. Campers can set up their tents or park their RVs in designated areas, providing a unique opportunity to experience the pinnacles up close, especially during sunrise and sunset.
    • Stargazing: Camping overnight offers a chance to enjoy the clear desert skies, which are perfect for stargazing and experiencing the tranquility of the desert.
  5. Filming and Events:
    • Film Location: The Trona Pinnacles have been used as a backdrop for numerous movies, TV shows, and commercials due to their otherworldly appearance. Productions like “Star Trek V: The Final Frontier” and “Planet of the Apes” have featured scenes shot at the pinnacles.
    • Special Events: Occasionally, the area hosts special events such as photography workshops, stargazing parties, and off-road vehicle rallies, providing unique opportunities for visitors to engage with the site.

Visitor Information

  • Location and Access: The Trona Pinnacles are about 20 miles east of Ridgecrest, California. The access road to the pinnacles is a graded dirt road off Highway 178, which can be rough in places but is generally passable for most vehicles.
  • Facilities: The Trona Pinnacles do not have developed facilities. Visitors should come prepared with their water, food, and supplies. Portable toilets are sometimes available, but it’s best to be self-sufficient.

Best Times to Visit

  • Spring and Fall: These seasons offer mild temperatures, making it the best time for outdoor activities such as hiking and camping. Springtime may also bring wildflower blooms, adding color to the landscape.
  • Winter: Winter can be a good time to visit if you prefer cooler weather, but be prepared for cold nights. The clear winter skies are excellent for stargazing.

Conservation and Preservation

  • Protected Area: The Trona Pinnacles are managed by the Bureau of Land Management as part of the California Desert National Conservation Area. Efforts are made to preserve the site’s unique geological features and natural beauty.
  • Responsible Tourism: Visitors are encouraged to practice Leave No Trace principles, respecting the delicate desert environment and minimizing their impact on the land and formations.

Nearby Attractions

  • Searles Valley Minerals: The nearby town of Trona is known for its mineral processing facilities. The Searles Valley Minerals plant conducts an annual Gem-O-Rama event, where visitors can collect various minerals and crystals from the Searles Lake deposits.
  • Death Valley National Park: Located to the east, Death Valley National Park offers additional opportunities for exploring diverse desert landscapes, unique geological features, and historic sites.

Educational and Interpretive Programs

  • Guided Tours and Talks: Occasionally, the BLM or local organizations may offer guided tours and interpretive talks about the geology and natural history of the Trona Pinnacles, providing deeper insights into the site’s formation and significance.

The Trona Pinnacles offer a unique and memorable experience for visitors interested in geology, photography, outdoor adventure, and the natural beauty of the Mojave Desert. Whether exploring the pinnacles on foot, capturing their striking forms with a camera, or simply soaking in the serene desert atmosphere, the Trona Pinnacles provide an extraordinary destination for all who visit.


#8 – Amboy Crater: A Volcanic Landmark in the Mojave Desert


Amboy Crater – Outside looking in.

Amboy Crater is a remarkable natural feature in the Mojave Desert, offering visitors a unique opportunity to explore a dormant volcanic cinder cone and its surrounding landscape. Here’s an expanded look at what makes Amboy Crater a popular attraction:

Geological Significance

  • Formation: Amboy Crater is a cinder cone volcano that formed during an eruption approximately 79,000 years ago. The eruption produced the cone and extensive lava fields that stretch across the desert floor.
  • Volcanic Structure: The crater stands about 250 feet above the surrounding landscape and has a diameter of about 1,500 feet—the crater’s interior features a flat floor and a breached rim, indicative of past volcanic activity.

Attractions and Activities

  1. Hiking to the Crater:
    • Trail Information: The hike to the summit of Amboy Crater is a moderately challenging trek of about 3 miles round trip. The trailhead is equipped with interpretive signs that provide information about the volcanic history and the local ecology.
    • Trail Experience: The trail leads through lava fields and desert terrain, offering a chance to see various volcanic features up close. The ascent to the crater rim provides stunning views of the surrounding desert.
  2. Exploring the Crater:
    • Crater Interior: Once at the top, hikers can descend into the crater’s interior, which features a flat floor covered with volcanic ash and small rocks. It’s a unique landscape that feels almost otherworldly.
    • Scenic Views: The crater’s rim offers panoramic views of the Mojave Desert, including the vast lava fields and distant mountain ranges. The view is particularly striking at sunrise and sunset.
  3. Wildlife and Flora:
    • Desert Plants: The area around Amboy Crater is home to various desert plants, including creosote bushes, cacti, and wildflowers. During spring, the landscape can be dotted with colorful blooms.
    • Wildlife: Visitors might spot desert wildlife like lizards, snakes, and birds. Despite the harsh conditions, the area’s natural habitat supports a diverse ecosystem.
  4. Photography Opportunities:
    • Landscape Photography: The stark contrast between the black lava fields and the sandy desert creates dramatic photo opportunities. The crater’s unique geological features make it a favorite subject for photographers.
    • Astrophotography: Amboy Crater’s remote location and lack of light pollution make It an excellent spot for stargazing and astrophotography. The clear desert skies provide breathtaking views of the night sky.

Visitor Information

  • Location and Access: Amboy Crater is located off historic Route 66, near the town of Amboy. The site is accessible via a well-maintained dirt road and a parking area at the trailhead.
  • Facilities: The trailhead features shaded picnic tables, informational kiosks, and restroom facilities. There is also a viewing platform for those who prefer not to hike but still want to enjoy the scenery.

Historical and Cultural Context

  • Route 66: Amboy Crater is situated along the iconic Route 66, adding a layer of historical significance. The nearby town of Amboy and the famous Roy’s Motel and Café provide a nostalgic glimpse into the heyday of America’s Mother Road.
  • Cultural Significance: The crater and its surroundings have been a significant landmark for indigenous peoples, early travelers, and modern explorers. It has been a navigation point and a source of fascination for centuries.

Safety and Preparation

  • Hiking Precautions: Due to the harsh desert environment, hikers should come prepared with plenty of water, sun protection, and appropriate footwear. The trail can be challenging, especially in hot weather.
  • Weather Considerations: The best times to visit are during the cooler months of fall, winter, and early spring. Summer temperatures can be extreme, making hiking hazardous.

Conservation Efforts

  • Protected Area: Amboy Crater is designated a National Natural Landmark, recognizing its geological significance and ensuring its protection for future generations.
  • Responsible Tourism: Visitors are encouraged to practice Leave No Trace principles, respecting the delicate desert environment and preserving the area’s natural beauty.

Amboy Crater offers a unique blend of geological wonder, natural beauty, and historical intrigue. Whether you’re an avid hiker, a photography enthusiast, or simply curious about the natural world, Amboy Crater provides a memorable and enriching experience in the heart of the Mojave Desert.

Pinto Basin and Mountains

The Pinto Basin and Mountains, located in Joshua Tree National Park in southern California, are notable for their rugged terrain, diverse geology, and rich history. Here’s an overview of the key aspects of this region:

Geography and Geology

Pinto Basin

  • Location: The Pinto Basin is in the southeastern part of Joshua Tree National Park.
  • Terrain: The basin is characterized by broad, sandy expanses interspersed with rocky outcrops and occasional washes.
  • Geology: The basin’s geology is diverse, with ancient Precambrian rocks, including gneiss and schist, and recent sedimentary deposits. The basin’s alluvial fans are made of materials eroded from the surrounding mountains.

Pinto Mountains

  • Location: The Pinto Mountains lie to the south of the Pinto Basin.
  • Elevation: The mountains vary in elevation, with some peaks rising over 3,000 feet above sea level.
  • Geology: The mountain range comprises various rock types, including granitic and metamorphic rocks, indicative of a complex geological history involving volcanic activity and tectonic movements.


Prehistoric and Native American Presence

  • Pinto Culture: The region is named after the Pinto Culture, an early Native American group that inhabited the area around 8,000 to 10,000 years ago. Artifacts such as stone tools and points have been found, suggesting a hunter-gatherer lifestyle.
  • Native American Tribes: Various tribes, including the Chemehuevi and Cahuilla, lived in the region, relying on its resources for sustenance.

Historic Era

  • Mining: In the late 19th and early 20th centuries, the Pinto Basin and Mountains saw sporadic mining activity, primarily for gold and other minerals. Remnants of old mines and mining equipment can still be found in the area.
  • Homesteading: In the early 20th century, homesteaders attempted to settle in the region, though the harsh desert environment made it challenging.

Flora and Fauna

  • Flora: The Pinto Basin is home to various desert plant species, including creosote bush, Joshua trees, and ocotillo. The area’s unique ecosystem supports common and rare plant species adapted to the arid conditions.
  • Fauna: The Pinto Basin’s wildlife includes desert bighorn sheep, coyotes, jackrabbits, and numerous bird species. Reptiles such as lizards and snakes inhabit the area.

Recreation and Attractions

  • Hiking: The Pinto Basin offers several hiking opportunities, with trails ranging from easy walks to challenging backcountry routes. Popular trails include the Lost Palms Oasis and the Arch Rock Nature Trail.
  • Scenic Drives: The Pinto Basin Road provides a scenic drive through the basin, offering stunning landscape views and access to various trailheads and viewpoints.
  • Stargazing: The remote location and minimal light pollution make the Pinto Basin an excellent spot for stargazing and astrophotography.

The Pinto Basin and Mountains are a fascinating area within Joshua Tree National Park, offering visitors a glimpse into the natural and cultural history of the Mojave Desert.


History of the Salton Sea

Salton Sea view from Mastodon Peak

The Salton Sea, located in the Colorado Desert of Southern California, is a fascinating and complex body of water with a rich history shaped by both natural and human influences. Here’s an overview of its history:

Prehistoric and Early History

  1. Ancient Lake Cahuilla:
    • The Salton Sea’s basin has intermittently held water for thousands of years. The area was once part of Lake Cahuilla, a massive freshwater lake that existed during prehistoric times and was periodically filled by the Colorado River.
    • Native American tribes, such as the Cahuilla and Kumeyaay, lived around the lake and utilized its resources.

Formation of the Modern Salton Sea

  1. 1905-1907: Creation:
    • The modern Salton Sea was created by accident in 1905 when engineers working on irrigation canals for the Imperial Valley inadvertently diverted the entire flow of the Colorado River into the Salton Sink.
    • For nearly two years, the river flowed unchecked into the basin, filling it and creating the Salton Sea.

20th Century Development

  1. Agricultural Hub:
    • The region around the Salton Sea became a vital agricultural area due to the fertile soil and irrigation from the Colorado River.
    • Runoff from these agricultural activities has been a major source of water for the Sea.
  2. Mid-20th Century: Recreation Boom:
    • In the 1950s and 1960s, the Salton Sea became a popular recreational destination, often referred to as a “miracle in the desert.”
    • Resorts, marinas, and yacht clubs flourished, attracting celebrities and tourists for boating, fishing, and other water activities.

Environmental Challenges

  1. Rising Salinity and Pollution:
    • Over time, the Salton Sea’s salinity increased due to evaporation and lack of freshwater inflow: agricultural runoff containing fertilizers and pesticides further degraded water quality.
    • The increasing salinity began to harm fish populations, leading to mass die-offs and the collapse of the once-thriving fishing industry.
  2. Health and Environmental Concerns:
    • The drying of the Salton Sea has exposed toxic dust from the lakebed, posing health risks to surrounding communities.
    • The ecosystem has been severely impacted, with significant losses of fish and bird populations that once thrived in the area.

Modern Efforts and Challenges

  1. Restoration Efforts:
    • Numerous efforts have been proposed and some initiated to address the Salton Sea’s environmental issues. These include water management projects, habitat restoration, and dust suppression measures.
    • California state agencies and environmental groups continue to work on strategies to mitigate the ecological and health impacts.
  2. Ongoing Challenges:
    • Despite these efforts, the Salton Sea remains a critical environmental challenge. Balancing agricultural needs, wildlife conservation, and public health concerns continues to be a complex and contentious issue.

The history of the Salton Sea is a testament to the intricate interplay between human activities and natural processes. It serves as a poignant reminder of the consequences of environmental mismanagement and the ongoing need for sustainable solutions.

The Needles, Mohave Mountains, Arizona

The Needles in the Mohave Mountains of Arizona present a unique geological character.

Here’s an overview of the geology of this area:

Location and Formation

The Chemehuevi Mountains are located in southeastern California and extend into the Mohave Mountains in Arizona. This range is part of the Basin and Range Province and is characterized by its dramatic elongated mountain ranges separated by flat valleys or basins.

Erosional Features

The Needles within the Mohave Mountains are likely a result of extensive erosional processes that have sculpted the landscape over millions of years. Weathering and erosion, driven by temperature fluctuations, water action, and wind, have exposed the harder, more resistant rock formations. These processes create the sharp, needle-like spires and rugged terrain typical of the area.

Ecological and Environmental Significance

The Mohave Mountains’ geological diversity supports various habitats and is significant for biodiversity. The area’s unique geology affects soil composition, water availability, and vegetation types, all of which contribute to the ecological complexity of the region.

These geological and erosional processes have given the Mohave Mountains their distinctive rugged appearance, making them a notable example of the dynamic Earth processes at work in the desert environments of the American Southwest.

Cat Dune – Hanging Dune

A “hanging dune” is a specific type of sand dune that forms on the leeward side of a hill or mountain, typically above the general level of the surrounding terrain. These dunes are essentially perched above other landforms, often appearing as though they are hanging on the slopes.

Here’s how they develop and some characteristics:


Hanging dunes primarily form in areas with significant wind activity where the topography causes the wind to deposit sand on steep slopes rather than just along flat surfaces. This process involves:

  • Wind Patterns: Strong, consistent winds carry sand from lower areas.
  • Obstacle Impact: When these winds encounter steep slopes or cliffs, their upward deflection causes a reduction in wind speed, dropping the sand and forming a dune.
  • Accumulation: Over time, more sand accumulates, stabilizing despite the steep slopes due to vegetation or moisture, further building the dune.


  • Location: They are typically found on the sides of hills, cliffs, or within mountain ranges where wind patterns are disrupted by the topography.
  • Stability: These dunes can be quite stable if vegetation anchors the sand, or they can be transient and shift with changes in wind patterns.
  • Ecological Impact: Hanging dunes can create unique microenvironments that support specialized plants and animals adapted to these specific conditions.

Geologic and Ecological Significance

  • Indicator of Wind History: The presence and orientation of hanging dunes can provide clues about historical wind directions and strengths.
  • Biodiversity: These dunes can host unique species that have adapted to the niche environments created by the unusual moisture and temperature conditions on the slopes.
  • Conservation: Due to their unique nature and the specialized ecosystems they support, hanging dunes can be important areas for ecological studies and conservation efforts.

Hanging dunes are less common than other dune types and require a unique set of environmental conditions to form and persist, making them particularly interesting for geologists and ecologists studying aeolian (wind-driven) processes and desert ecosystems.