The Walker Lane/Eastern California Sheer Zone is an extensive and complex tectonic rift system of mostly strike-slip transform fault strands east of the Sierra-Nevada, stretching longitudinally between the Sierra Nevada and the Basin and Range geomorphic/tectonic provinces, from approximately the Modoc Plateau in the north to the San Bernardino Mountains in the south.
The Walker Lane Belt and the San Andreas Fault System, together, define the North American-Pacific Plate boundary in California, and work in concert to accommodate relative tectonic movement and displacement between the plates.
The Walker Lane has been measured to express approximately 20% of the motion and strain between the Pacific and North American Plates, while the San Andreas System takes up approximately 80% of the tectonic energy of the plate margin.
