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Zzyzx - The Oldest Rocks in the World

A cache by Troutpro Send Message to Owner Message this owner
Hidden : 12/12/2010
1 out of 5
2.5 out of 5

Size: Size: other (other)

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Geocache Description:

The Mojave Desert is home to some of the oldest rocks in the world and this earthcache is at a location were some of them can be seen.

The mojave is home to all three kinds of rocks, sedimentary, metamorphic, and igneous, can be seen here. The earliest rocks that can be found are a form of pre-cambrian gniess. That puts them at about 1.6 billion years old! These formations can be observed here. These rocks were then followed by the paleozoic era. The Paleozoic era lasted from 570 Million years ago to 225 MYA. During that time period much of this area was covered by shallow seas. This is what weathered the older formations part way into the open and added sedimentary formations. Next came the Mesozoic era from 225 MYA to 65 MYA. During that time period the mountain in this area were pushed up by volcanism and fault action, adding the third type of rock, igneous. This is also pushed up the formations from the two previous time periods into the open. Next came the Cenozoic Era, from 65 MYA to the present day. This is when ice ages and weathering from water and air exposed the formations even more up until the present day.  Fualt in the area continue to push the rocks into the open and even fold the rocks so that the older formations are above the younger formations. The geology of the area continues to change even today. This is evident because earthquakes still ocasionally rock the area.

It's easy to identify the different kinds of rocks in the area. The sedimentary rocks tend to be low-lying with layers visible within them. the igneous rocks tend to be higher up and have a darker color. The metamorphic rocks can be just about anywhere and tend to have a similar color to the igneous rocks, but can be identified by their slightly lower position in the hills.

To get credit for this earthcache e-mail me the answers to the following questions:
1. The GC code and name of this cache.
2. The number of people in your group.
1. Formations of all three kinds of rock can be seen here, in what direction is each one?
2. Based on the weathering of the metamorphic rock, are they the precambrian rocks or newer formed ones?
3. how does the color of the rocks around the highway compare to that of the rocks that form the hills?
4. How does the answer to number three support the fact that during the Paleozoic era, this area was covered by seas?
5. What formations have the most weathering?

Note: This area has a high population of rattlesnakes!

Additional Hints (Decrypt)

ab arrq gb yrnir lbhe N/P'rq pne

Decryption Key


(letter above equals below, and vice versa)



428 Logged Visits

Found it 422     Didn't find it 1     Write note 4     Publish Listing 1     

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Current Time:
Last Updated: on 1/13/2018 2:12:43 PM (UTC-08:00) Pacific Time (US & Canada) (10:12 PM GMT)
Rendered From:Unknown
Coordinates are in the WGS84 datum

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