Читать книгу Trinity Alps & Vicinity: Including Whiskeytown, Russian Wilderness, and Castle Crags Areas. A Hiking and Backpacking Guide онлайн

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These mountains are only vaguely related, geologically, to the Coast Range to the west, and not related at all to the volcanic Cascades beginning with Lassen Peak and Mount Shasta to the east. They are, in fact, the southern part of the Klamath Mountains, which include the Marbles and Siskiyous farther north. The Klamath Mountains harbor some of the oldest rocks in California. These rocks originated as offshore sediments, largely volcanic in origin, which were repeatedly uplifted, folded, and combined with the granite bedrock below the seafloor, creating an amalgam of varied rock types formed at different times, by different means, and in different locations. In the process, tremendous pressures metamorphosed the deposits into uptilted and distorted strata of slate, quartzite, schist, gneiss, chert, and soapstone. Isolated pockets of unmetamorphosed sandstones, limestones, mudstones, and conglomerates can be attributed to later sedimentation and fallout from eruptions in a nearby volcanic chain. Geologists refer to this widely varied, complex, and mixed-up geology as the Klamath Knot.