Santa Ana Mountains - Fernando Formation EarthCache

Parking cannot be found at the above coordinates. The above coordinates are for the site of the Fernando Formation. Parking can be found at the waypoints provided.

The Fernando formation is a rock formation in the northern parts of the Santa Ana Mountains and extends into the Chino hills area as well as parts of Anaheim Hills. Other sections of the Fernando formation can be found in the Santa Monica mountains just west of Los Angeles. This rock formation was created anywhere from 5.3 - 2.6 million years ago. Speaking in geologic terms, this is a fairly new formation considering the earth has been around for over four billion years. The formation itself is made of three types of sedimentary rocks. They are siltstone, sandstone, and conglomerate. All of which is evidence that this are was underwater for quite some time. So how do these different types of rock form?

Siltstone is exactly what it sounds like. It's a stone made out of silt. Silt that came from fine powdery sediments from the Pacific, and deposited on the ocean floor. Water from the ocean becomes trapped inside the rounded powder which turns it into a muddy substance. When the Fernando Formation finally uplifted, the water that was trapped in the mud evaporated, leaving behind mainly salt, but also a hard brown rock known as siltstone.

Conglomerate is very similar to siltstone. Instead of having fine powdery sediments, conglomerate is made of large sediments and is formed deeper in earth's crust. In order for conglomerate to form, you need heat and pressure to physically fuse large sediments together, unlike siltstone. Overtime, the land from the ocean uplifts, brining the rock with it. Conglomerate is located below the siltstone because it forms at a deeper depth.

Sandstone is a little more easier to understand. It's exactly what it sounds like. It's a stone, made of compacted sand. If you rub at it long enough, small pieces of sand will fall off. But please, do not try that here and tamper with the rocks at this location. Sandstone is formed during a processes called lithification. The first step in lithification is to have bare rock exposed to the elements where it can be eroded. When wind or water erodes the rock away, small fragments of the original rock are carried to a different location. Overtime, these small pieces of rock are carried to the ocean, where they sink to the bottom of the sea floor and accumulate. After a few million years, and with added heat and pressure, the sand compacts and creates sandstone.

http://pubs.usgs.gov/pp/0420d/report.pdf

http://archives.datapages.com/data/pac_sepm/109/109001/pdfs/349.htm

https://pubs.er.usgs.gov/publication/pp420D

http://study.com/academy/lesson/conglomerate-definition-uses-facts.html

http://www.blinn.edu/STEM/Geology/faculty/Sed_Web_Page/pages/Siltstone.htm

https://morgoblogocon.wordpress.com/2011/08/24/denali/

http://www.mnh.si.edu/earth/text/dynamicearth/6_0_0_GeoGallery/geogallery_specimen.cfm?SpecimenID=2018&categoryID=4&categoryName=Rocks&browseType=type&typeID=22&typeName=Sandstone

TO LOG A FIND ON THIS CACHE YOU MUST E-MAIL (NOT THE GEOCACHING.COM MESSAGE CENTER) ME THE CORECT ANSWERS BEFORE YOU LOG A FIND. ANY INCORRECT ANSWERS WILL RESULT IN A DELETED LOG

**No group emails will be accepted as for me, this is a form of cheating. If this happens, all your logs will be deleted. Any incorrect or inaccurate answer will result in a deleted log, so don't let this happen to you!**

1. Santa Ana Mountains - Fernando Formationon the first line of your email.

2. Out of the three sedimentary rocks that make up the Fernando Formation we've discussed above, which ones are the most abundant at this site AND why do you think this is? ALSO, list the order from newest to oldest (top to bottom) in which these rocks start to appear on the exposed rock.

3. Explain the erosion process here AND which rock(s) (that you answered above) are eroding the fastest? ALSO, explain if the exposed rock is growing or shrinking? In other words, is it growing faster, due to tectonic movements, than the cliff can be eroded or vise versa.

4. About half way down the middle of the exposed rock you'll see a fracture that is angled at about 75 degrees. The west side of the exposed rock is a different, distinctive color than the east side. Why do you think there is completely different colorations here?