Parking in Malibu Creek State Park requires a fee, but will get you quite a bit closer to the earthcache. Free parking is available on surrounding streets, but it gets very crowded on weekends.
The Santa Monica Mountains have only been growing for the past few million years. Prior to that, the Ancient Malibu Creek had formed meanders across the prehistoric landscape. The Santa Monicas began growing as a bend formed in the San Andreas Fault. This bend causes the North American and Pacific Plates to be slightly pressed together instead of the just the typical strike slip faulting that the San Andreas is famous for.
As the mountains were pushed up, Ancient Malibu Creek continued flowing across the top of the incipient mountain range. The rate of erosion down into the growing mountains exceed the rate that the mountains grew up. As a result, the ancient creek meanders were eroded down into the underlying rock cutting through ridges as they grew on each side of the creek. Where the surrounding rock is strong, the creek flows through sheer walled canyons, while wider valleys form where the surrounding rock is weaker.
The coordinates bring you to an overview of where Malibu Creek cuts through a ridge of Conejo Volcanics, a well-cemented rock. Notice that the ridge of Conejo Volcanics runs northwest/southeast and the creek cuts a U-shaped mender through the ridge heading south then turns around and cuts back to the northeast (the valley you most likely hiked up).
This cut through the ridge is the geomorphologic feature called a water gap. There are additional water gaps both upstream and downstream in Triunfo Canyon.
On a larger scale, the start of Malibu Creek and its many tributaries are north of the Santa Monica Mountains. Malibu Creek then cuts through the Santa Monicas roughly perpendicular to the mountain range to drain into the Pacific Ocean south of the Santa Monicas. Malibu Creek cuts a water gap through the Santa Monica Mountains.
Send me a note with :
- The text "GC1BFCR Malibu Creek Water Gap" on the first line
- The number of people in your group.
- Describe the character of the stream flow west of the primary coordinates and what happens to the water flow as the stream flows northeast. What would account for that difference?
- Estimate the depth that Malibu Creek has eroded down through the ridge. You may want to check out GC1BFCN for a better view, or walk down to the dam.
The above information was compiled from the following sources:
- Santa Monica Mountains National Recreation Area Paleontological Survey, Alison L. Koch, Vincent L. Santucci, Ted R. Weasma; Geologic Resources Division National Park Service Denver, Colorado NPS/NRGRD/GRDTR-04/01 2004
- SEISMIC HAZARD ZONE REPORT FOR THE MALIBU BEACH 7.5-MINUTE QUADRANGLE, LOS ANGELES COUNTY, CALIFORNIA, SEISMIC HAZARD ZONE REPORT 050, 2001, DEPARTMENT OF CONSERVATION Division of Mines and Geology