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X-WR-CALDESC:Events for ABDNHA
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DTSTART;TZID=America/Los_Angeles:20260109T183000
DTEND;TZID=America/Los_Angeles:20260109T193000
DTSTAMP:20260106T002752Z
CREATED:20260106T002752Z
LAST-MODIFIED:20260106T002752Z
UID:10000920-1767983400-1767987000@abdnha.org
SUMMARY:Lecture: The Story of the Salton Sea - FULL
DESCRIPTION:THIS PROGRAM IS FULL. \nSpeaker: Dave Blanchet\, (ret.) Hydrologist \nFirst 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.
URL:https://abdnha.org/activity/lecture-the-story-of-the-salton-sea-full/
LOCATION:ABDNHA Library\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:In-Person Lecture
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BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260110T083000
DTEND;TZID=America/Los_Angeles:20260110T120000
DTSTAMP:20251224T231438Z
CREATED:20251224T231438Z
LAST-MODIFIED:20251224T231438Z
UID:10000891-1768033800-1768046400@abdnha.org
SUMMARY:Hike: West Truckhaven Wash (Moderate) - FULL (waitlist)
DESCRIPTION:Leader: Kathy Bussey\, ABDNHA Volunteer \nA mile east of Arroyo Salado\, on the North side of S22\, 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 three-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.
URL:https://abdnha.org/activity/hike-west-truckhaven-wash-moderate-full-waitlist/
LOCATION:ABDNHA Parking Lot\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:Hike
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260112T080000
DTEND;TZID=America/Los_Angeles:20260112T120000
DTSTAMP:20260112T190351Z
CREATED:20251224T231735Z
LAST-MODIFIED:20260112T190351Z
UID:10000892-1768204800-1768219200@abdnha.org
SUMMARY:Hike: Truckhaven Rocks to Coachwhip (Moderate to Fairly Strenuous) - FULL (waitlist)
DESCRIPTION:Leader: Bruce Kelley\, ABDNHA Volunteer \nHIKE IS FULL – PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist. \nThis walk will explore ancient rocks that were split from the Santa Rosa Mountains and uplifted due to tectonic action\, located just northwest of S22\, near the Salton Sea. This is a moderate three-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 and 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 am. \n 
URL:https://abdnha.org/activity/hike-truckhaven-rocks-to-coachwhip-moderate-to-fairly-strenuous-full-waitlist/
LOCATION:ABDNHA Parking Lot\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:Hike
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260123T183000
DTEND;TZID=America/Los_Angeles:20260123T193000
DTSTAMP:20260119T014131Z
CREATED:20260113T000525Z
LAST-MODIFIED:20260119T014131Z
UID:10000933-1769193000-1769196600@abdnha.org
SUMMARY:Lecture: Flash Floods in Semi-Arid Landscapes - FULL (waitlist)
DESCRIPTION:Special Earth Sciences Weekend! \nSpeaker: Suzanne Walther\, Ph.D.\, University of San Diego \nPROGRAM IS FULL – PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist. \nIt 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. \n\n\n  Get Tickets
URL:https://abdnha.org/activity/lecture-flash-floods-in-semi-arid-landscapes-full-waitlist/
LOCATION:ABDNHA Library\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:In-Person Lecture
ATTACH;FMTTYPE=image/jpeg:https://abdnha.org/wp-content/uploads/2025/12/260123_Flash-Floods.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260124T084500
DTEND;TZID=America/Los_Angeles:20260124T123000
DTSTAMP:20251226T232137Z
CREATED:20251206T215505Z
LAST-MODIFIED:20251226T232137Z
UID:10000822-1769244300-1769257800@abdnha.org
SUMMARY:Field Trip: Ancient Lake Cahuilla - FULL (waitlist)
DESCRIPTION:Special Earth Science Series! \nFIELD TRIP IS FULL – PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist \nLeader: John Peterson\, Hydrologist and Geologist \nApproximately 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.
URL:https://abdnha.org/activity/field-trip-ancient-lake-cahuilla/
LOCATION:ABDNHA Parking Lot\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:Field Trip
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260124T183000
DTEND;TZID=America/Los_Angeles:20260124T193000
DTSTAMP:20260120T182142Z
CREATED:20251206T215505Z
LAST-MODIFIED:20260120T182142Z
UID:10000821-1769279400-1769283000@abdnha.org
SUMMARY:Lecture: Geology of San Diego County’s Peninsular Ranges
DESCRIPTION:Special Earth Science Series! \nSpeaker: Geologist Don Barrie \nPlease 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. \n\nGet Tickets
URL:https://abdnha.org/activity/lecture-geology-of-san-diego-countys-peninsular-ranges/
LOCATION:ABDNHA Library\, 652 Palm Canyon Drive\, Borrego Springs\, CA\, 92004\, United States
CATEGORIES:In-Person Lecture
ATTACH;FMTTYPE=image/jpeg:https://abdnha.org/wp-content/uploads/2025/12/Peninsular-Ranges.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20260125T090000
DTEND;TZID=America/Los_Angeles:20260125T150000
DTSTAMP:20251226T231945Z
CREATED:20251206T215505Z
LAST-MODIFIED:20251226T231945Z
UID:10000818-1769331600-1769353200@abdnha.org
SUMMARY:Field Trip: Geology of San Diego County’s Peninsular Ranges - FULL (waitlist)
DESCRIPTION:Special Earth Science Series! \nFIELD TRIP IS FULL – PLEASE CALL ABDNHA at 760-767-3098 to get on waitlist \nLeader: Geologist Don Barrie \nNote the  start and end locations detailed below. Don will lead the group on an exploration of the rocks along Sunrise Hwy.\, 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 Hwy. and Interstate 8\, then follow Sunrise Hwy. 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\, go to www.abdnha.org\, or call 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. \nStart and end locations details: 9:00 am – 3:00 pm\, Sun.\, Jan. 25\, ending at the Eagle-High Peak mine in Julian. Meet at 9:00 am along Sunrise Hwy. (County Rd. S1)\, about 1/4-mile north of the Interstate 8 Sunrise Hwy. 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.
URL:https://abdnha.org/activity/field-trip-geology-of-san-diego-countys-peninsular-ranges/
CATEGORIES:Field Trip
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