Hike: Truckhaven Rocks to Coachwhip (Moderate to Fairly Strenuous) – FULL (waitlist)

Leader: Bruce Kelley, ABDNHA Volunteer HIKE IS FULL - PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist.and see if This walk will explore ancient rocks that were split from the Santa Rosa Mountains and uplifted due to tectonic action, located just northwest of S-22, near the Salton Sea. This is a moderate+ 3-mile hike mostly in Truckhaven Wash, circling behind the main rocks visible from the highway. We will leave that wash and cross a ridge to emerge in Coachwhip Canyon. The last part up and the first part down the ridge are steep. Bring water, hat, sunscreen, hiking shoes & you may want a stick (I’ll have several extras). Bring your AWD or 4WD vehicle if possible. We are going to do a shuttle hike. Meet in the parking lot of ABDNHA by 7:50 a.m.

Continue ReadingHike: Truckhaven Rocks to Coachwhip (Moderate to Fairly Strenuous) – FULL (waitlist)

Hike: West Truckhaven Wash (Moderate) – FULL (waitlist)

Leader: Kathy Bussey, ABDNHA Volunteer HIKE IS FULL - PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist. A mile east of Arroyo Salado, on the North side of S-22, lie the unique Truckhaven Rocks, a Swiss cheese sandstone formation. This 2.3-mile round-trip hike skirts the West side of the Rocks. We will walk up a sandy wash that eventually narrows between weathered sandstone walls. The hike is easy. However, there is one 3-foot dry waterfall that we need to climb up. Meet at ABDNHA and be willing to carpool. 2WD OK. Bring water, snacks, a hat, and sturdy boots. Call 760-767-3098 to reserve. Limit 18 people.

Continue ReadingHike: West Truckhaven Wash (Moderate) – FULL (waitlist)

Lecture: The Story of the Salton Sea

Speaker: Dave Blanchet, (ret.) Hydrologist First there was the geology, and then came the flood.  The Salton Sea is located along the San Andreas Fault, and it is geology that repeatedly created and drained a vast natural lake over millions of years, called Lake Cahuilla, in what is now the Imperial Valley. Starting in the 20th century, agriculture began to flourish in California’s Imperial Valley, and diversion canals were dug to divert water from the Colorado River into the dry desert.  But the wild nature of the Colorado River soon took the upper hand. Events went horribly awry as record-breaking floodwaters destroyed the manmade dams and canals, and the full flow of the Colorado River flowed unabated into the Salton Trough for two years. Only through immense effort was the flooding finally stopped, and the Colorado River returned to its course, flowing into the Sea of Cortez.  Tonight’s speaker, Dave Blanchet, is a retired hydrologist from Anchorage, Alaska, and a lifetime member of ABDNHA.  General Public: $12, Members: $10, Volunteers: $8. Please register at www.abdnha.org or at the Nature Center, 760-767-3098.

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Read more about the article Lecture: Flash Floods in Semi-Arid Landscapes

Lecture: Flash Floods in Semi-Arid Landscapes

Special Earth Sciences Weekend Speaker: Suzanne Walther, Ph.D., University of San Diego It has been said that the two most common ways to die in the desert are from thirst and from drowning. Flash floods are the leading weather-related cause of death in the U.S. and many parts of the world, and cause billions of dollars in damage. Dr. Suzanne Walther is a fluvial geomorphologist. She studies rivers, streams, floods, sediment movement, and how the natural flow of water shapes the landscape, interacts with ecosystems, and significantly impacts human development. The focus tonight is on flash floods in semi-arid areas, such as Borrego Springs, where they can occur, the conditions that lead to their formation, the powerful forces they unleash, their effects on water supply and drought, and what can be done to mitigate their destructive impact on human development. In the ABDNHA Library. General Public: $12, Members: $10, Volunteers: $8. You can register online at abdnha.org or at the Nature Center, 760-767-3098.

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Field Trip: Geology of San Diego County’s Peninsular Ranges – FULL (waitlist)

Special Earth Science Series FIELD TRIP IS FULL - PLEASE CALL ABDNHA to get on waitlist *Note the start and end locations in the description below! Leader: Geologist Don Barrie Don will lead the group on an exploration of the rocks along Sunrise Highway, west of Borrego Springs. The rocks in this area comprise part of a regional geologic suite known as the Peninsular Ranges Batholith (PRB), which extends from southern Baja, California, northward into the Palm Springs area. We'll meet near the intersection of Sunrise Highway and Interstate 8, then follow Sunrise Highway into the Laguna Mountains, stopping to examine rock exposures along the way. The last stop will be in Julian, where the group will tour the Eagle/High Peak gold mine and learn about the gold rush in Julian during the 1870s. On the field trip, we'll discuss the geologic story of how the gold got into the rocks. During the gold mine tour, we'll learn how hard-rock miners got the gold out of the rocks. To register, www.abdnha.org, or the Nature Center at 760-767-3098. General Public: $20, Members: $14, Volunteers: $10. Please note that an additional $14 entrance fee per person is required, payable upon entry to the mine. Field Trip Details: 9 a.m. - 3 p.m., Sun., Jan. 25, ending at the Eagle-High Peak mine in Julian. Meet at 9 a.m. along Sunrise Highway (County Road S1), about 1/4 mi north of the Interstate 8 Sunrise Highway exit, in a dirt parking area along the east side of the road. Bring lunch and water. 2WD okay. Please check the local weather in Mt. Laguna and dress accordingly (it may be chilly!). Carpooling is highly recommended. Heavy rain or snow cancels. The trip ends at the Eagle-High Peak Mine in Julian.

Continue ReadingField Trip: Geology of San Diego County’s Peninsular Ranges – FULL (waitlist)
Read more about the article Lecture: Geology of San Diego County’s Peninsular Ranges

Lecture: Geology of San Diego County’s Peninsular Ranges

Special Earth Science Series Speaker: Geologist Don Barrie Please join Mesa College geology professor and ABDNHA board member, Don Barrie, for this lecture on San Diego County’s Peninsular Ranges, with emphasis on the Laguna Mountains west of Borrego Springs. Don’s lecture will focus on how plate tectonic processes have created the complex collage of igneous and metamorphic rocks exposed both regionally, throughout southeastern California, and locally, in the Lagunas. In the ABDNHA Library. General Public: $12, Members: $10, Volunteers: $8. A related field trip is scheduled for Sun., Jan. 25.

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Field Trip: Ancient Lake Cahuilla – FULL (waitlist)

Special Earth Science Series FIELD TRIP IS FULL - PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist. Leader: John Peterson, Hydrologist and Geologist Approximately 12,000 years ago, the Colorado River altered its course, forming a massive prehistoric lake known as Lake Cahuilla, which is now the Salton Sea.   The lake served as a vital resource for the Cahuilla, Kumeyaay, and Cocopah peoples. Over the centuries, the lake filled and dried up many times. It last filled between 1731 and 1733. Hydrologist John Peterson will lead a half-day field trip to the Salton Sea, where participants can explore the ancient lake's remnants, including visible "bathtub rings" and fishing traps. Meet at ABDNHA. General Public: $18, Members: $12, Volunteers: $10. Register online or at the Nature Center, 760-767-3098.

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Hike: Exploring Coyote Canyon

Leader: Marlin Burke, Naturalist Volunteer We meet at ABDNHA and then carpool to Coyote Creek, where we explore the history of Native Americans and early settlers, geology, paleontology, Plant life, Coyote Creek itself, and whatever else catches our attention. Easy walking; driving on a dirt road. High clearance 2WD or SUV acceptable due to dirt road with possible rocks or potholes. No charge, but registration is required.  Call or visit the ABDNHA Nature Center, 760-767-3098.

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Hike: Geology Hike to Canyon Sin Nombre (Moderate) – FULL (waitlist)

HIKE IS FULL. Call 760-767-3098 to get on waitlist. Leader: Geologist Don Barrie Join Don on a hike to explore the geology of Canyon Sin Nombre, located in a major fault zone, and shaped by ancient faulting, sedimentary rock, and ongoing erosion. Meet along S2, at the intersection of  S2 and Canyon Sin Nombre Road. Bring lunch and water. 4WD required. Register at the ABDNHA Nature Center or call 760-767-3098. Note: Meet at the intersection of S2 and Canyon Sin Nombre Road.

Continue ReadingHike: Geology Hike to Canyon Sin Nombre (Moderate) – FULL (waitlist)

Hike: West Butte, Hawk Valley (Fairly Strenuous) – FULL (waitlist)

HIKE IS FULL. Call 760-767-3098 to get on waitlist. Trip leader: Tom Keffer Gorgeous sandstone cliffs, killer views out the Borrego Valley, all in a close-to-home package. We will be entering from Hawk Valley, then climbing up a hidden slot to the ridge above, then on to West Butte. 3.5 miles RT, 500' of climbing, steep sections with scary drop offs, some step-ups. Access road is suitable for most 2WD. Meet at ABDNHA by 7:50 a.m. Bring lunch/snacks, water. Call 760-767-3098 to reserve. Limit: 10.

Continue ReadingHike: West Butte, Hawk Valley (Fairly Strenuous) – FULL (waitlist)