Children resting on bench along Upper Lake Loop interpretive trail, Bear Creek Redwoods Preserve / photo by Alisha Laborico

Bear Creek Redwoods Upper Lake Interpretive Tour: Significant Geology

Upper Lake Loop interpretive trail, Bear Creek Redwoods Preserve (Alisha Laborico)
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A cultural landscape is a place with both a unique natural setting and important human history. At Bear Creek Redwoods, the cultural landscape lies on a pressure ridge formed by the San Andreas Fault.

Here, the fault is not a single fissure, but rather a wide band of small fault lines, or traces. Both the ridge and Upper Lake were formed by the movement of the land along the fault. This fault activity also influenced how humans shaped the landscape.

Sag pond diagram
The movement of the plates can push land up into pressure ridges or cause it to slump into sag ponds. (Image courtesy of geocaching.com)

The 1906 earthquake destroyed James L. Flood’s mansion, and inspired Tevis to construct his estate with impressive seismic engineering. For example, the retaining walls he built to expand the flat top of the ridge are stabilized by massive ship anchor chains. These walls survived the 1989 Loma Prieta earthquake and still exist today.

Next Stop: Exotic Versus Invasive Species

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