Anaheim Landing is registered as a California State Historical Landmark site number 218. It dates back to the late 1850s when Anaheim was becoming an important industrial city and needed a shipping port, which was located here in Seal Beach. The above coordinates will bring you to a state historical marker. The marker is made up of several different types of rocks, a few of which are worth creating into an earthcache. Be sure to find the nearby traditional cache here as well.
The monumnet you see in front of you contains very well preserved speciments of agates and one notable peice of obsidian, better known as volcanic glass. Agates are made up of mostly chalcedony and quartz while the obsidian has no mineral structure (as it is considered a type of glass and is why it is smooth and appears black in color). Agate is a type of sedimentary and igneous rock. Quartz and other disolved minerals in water find they way into an igneous cavity. Overtime, these minerals in solution start to crystalize within these cavities and beautify crystals form. There are several nice examples on this state historical marker.
Obsidian is formed when lava, usually basaltic in composition, is rapilidy cooled or quenched. This means there was not enough time for the minerals to fully cool and crystalize out, hence why obsidan contains no mineral structure. These are commnly found near basalt volcanoes such as those found on the Hawaiian Islands or in Iceland. Obsidian is usually smoothed and sometimes contains ripples in which you can tell the direction of lava flow.
For reference, the obsidian is the very dark, smooth rock about 3 rocks below the word "STATE" in the last line of the historical marker. The agates are more plentiful, with two of them just above the 2 stars at the top of the historical marker. And the other 2 are just above the "A" and the "G" in the title of the historical marker.
Works Cited
https://geologycafe.com/class/chapter3.html
TO LOG A FIND ON THIS CACHE YOU MUST ANSWER ALL THE QUESTIONS BELOW. YOU CAN CONTACT ME THROUGH MY EMAIL OR THE GEOCACHING MESSAGE CENTER TO SEND YOUR ANSWERS. ANY INCORRECT ANSWERS MAY RESULT IN A CLARIFICATION RESPONSE FROM ME.
1. "Anaheim Landing" on the first line of your email AND list all geocaching names of your party so I can match your answers to them. If you all want to learn something, I would prefer each cacher send me individual emails in the spirt of earthcaching.
2. Describe the textures and colors of the (a) agates and (b) obsidan.
3. Using the mineral chart above, what types of minerals do you see in the (a) agates and (b) obsidan?
4. Among the agates, do the colors (and the minerology) appear the same?
5. Describe the patterns you see in the mineralogy of the aggates. Specifically, are they flat, wavy, ciruclar, etc.? What might this tell you about the flow of water as it was forming?
