The Maacama Fault is a right lateral-moving (dextral)
geologic fault located in the
Coast Ranges of northwestern
California. It is considered to be the northernmost segment of the
Hayward Fault subsystem of the
San Andreas Fault zone.
Creep along the Maacama is about 8 mm per year, consistent with the steady movement along the rest of the Hayward Fault system. It is also capable of producing large earthquakes.[1][2]
The Maacama Fault runs just east of
Ukiah and just west of
Willits.
^Larsen, M.; Prentice, C. S.; Kelsey, H. M.; Zachariasen, J.; Rotberg, G. L. (April 2005). "Paleoseismic Investigation Of The Maacama Fault At The Haehl Creek Site, Willits, California". Geological Society of America Abstracts with Programs. 37 (4): 68.