Trails Report: Explore geologic wonders

Nestled in Long Valley Caldera, the Mammoth Lakes Trail System (MLTS) is home to many fascinating geologic wonders. From CO2  vents, volcanic fissures, pumice strewn craters, glacial moraines, hot springs, and one mammoth ski hill, the geologic past and present of the Eastern Sierra is exemplified throughout the MLTS.

Though many are familiar with the CO2  vents which have laid waste to the mixed conifer forest surrounding Horseshoe Lake, much less visited are Inyo Craters—part of a larger volcanic event extending north to Mono Basin, along the “earthquake fault” south to Red Cones.

This week, MLTS stewards led their first interpretive geology and bird walk at Inyo Craters. These walks are offered free to the public throughout the season. Also this week, Friends of the Inyo trail crews dug in on a five week project to maintain the much used Convict Lake trail, home to some of the best examples of glacial moraines found anywhere in the Sierra.

While thousands of visitors come to hot creek geologic site and Dave McCoy’s ski hill each year for recreation, the geologic composition of the Eastern Sierra has historically attracted people to the MLTS for different reasons. Rumors of the lost cement-mine on Mammoth Mountain first brought gold and silver speculators to the Lakes District in the latter days of the 19th century. Though the cement mine remained an unsubstantiated myth, several small mining operations sprang up on nearby Mineral Hill (Red Mountain) and brought the first year-round settlers to the MLTS. While these earlier attempts at mining were eventually abandoned, a saddle trail sprang up from Mammoth City—over Mammoth Pass to Fresno Flats (Oakhurst) and much-developed the MLTS region.

Later ventures found Archie Mahan and son forming the Mammoth Consolidated Mine. Though this venture was eventually defeated by the Great Depression, Archie Jr. went on to operate Red’s Meadow Pack Station, marking the transition of local economy from mining to tourism. Friends of the Inyo stewards and volunteers will be leading weekly Consolidated Mine Tours (Thursdays 1 p.m. at Heart Lake trailhead) of this latter-day mining operation, and much of the buildings, machinery, and stamp mills of this and earlier ventures remain throughout the MLTS for self-exploration. Please visit friendsoftheinyo.org or swing by the Mammoth Lakes Visitor Center for more information on weekly Consolidated Mine Tours and Inyo Craters geology/ bird walks. Also, don’t forget to join Friends of the Inyo, MLTPA, the town of Mammoth Lakes, and local businesses for our next summer of stewardship volunteer day at Minaret Vista, Saturday July 19th at 8:30 am.