This cliff face can be found along West Cliff Drive at John Street. The Quaternary deposits show many different layers which vary greatly in color and grain size; from fine sands to coarse channel deposits.

The sediments at the top of this cliff face along West Cliff Drive are generally referred to as recent from a geological perspective. They are from the Quaternary Period, which is made up of the Holocene (the last 12,000 years) and the Pleistocene (12,000 to 2.6 million years ago). The change between the Pleistocene and the Holocene is marked by the end of the last glaciation and the beginning of the warm period of the last twelve thousand years.

Along West Cliff Drive near John Street, very carefully walk down to the right of the garbage cans where there is a steep path through the ice plant and you will see the above profile.

Interestingly, a whole new geologic period, the Anthropocene, may soon be officially added to the geologic time scale. The Anthropocene is a recent term that recognizes the extent and impact of human activities on the earth; like our ability to outline the planet in lights. The Anthropocene will likely start at the beginning of the industrial revolution.

The Earth at night, a composited night-time image of the world during the anthropocene. Data courtesy Marc Imhoff of NASA GSFC and Christopher Elvidge of NOAA NGDC. Image by Craig Mayhew and Robert Simmon, NASA GSFC.

Take the Self-Guided Mobile Tour

This piece is part of the West Cliff Drive Tour. Download the free app with many tours of the Santa Cruz area and beyond.

Go to Mobile Ranger Guides in the Apple App Store

Go to Mobile Ranger Guides in the Google Play Store

Sources Used
- Anthropocene. Wikipedia. http://en.wikipedia.org/wiki/Anthropocene.
- International Commission on Stratigraphy 2012.
- Our Ocean Backyard: Ancient mud, diatoms and whales. Gary Griggs. Santa Cruz Sentinel. February 27, 2010. www.santacruzsentinel.com/localstories/ci_14482797.
- Personal Communication with Gary Griggs, Distinguished Professor of Marine Sciences, University of California Santa Cruz, February 2012.
- Quaternary. Wikipedia. http://en.wikipedia.org/wiki/Quaternary.