Beach Treasures from Japan Rocks and Sand Dollars

Metamorphic Rocks Method: Beach combing fieldtrip in Japan Collection: Slate and Green Slate (see picture on display board) Interpretation: Metamorphic rock forms from pre-existing rock exposed to high temperatures and pressures which causes them to change. Metamorphic rock forms part of the earth’s crust. It contains crystals and can be layered. Slate is a hardened form of shale (clay) and resists harsh weather and repels water. It is used for student writing tablets. Green slate obtains its green color from chlorite. It’s formed from many different types of rock such as quartz, feldspar and mica.

Sedimentary Rocks Method: Beach combing fieldtrip, Japan Collection: Magnified Grains and Chert Interpretation: Magnified Grains were once big rocks that are broken down by erosion into small, smooth stones; Chert is like quartz which contains silicon dioxide and other elements, and is green and white in color. (See display board)

Igneous Rocks Method: Beach combing fieldtrip in Japan and a purchased science kit Collection: Pumice, Andesite, Banded Rhyolite, Welded Tuff, Cinders, Geyserite, Obsidian, Basalt. (See display board) Interpretation: Igneous rock is formed by great heat or lava that crystallizes. It contains silicon, oxygen and other elements. Pumice is made from airy lava that dries quickly and forms a light rock with holes. Andesite is a fine-grained rock formed from lava in subduction zones where lava is thrust upward when the earth’s plates collide. Rhyolite is formed from many other types of rocks called quartz, feldspar, mica and glass. It is a fine or very fine rock. Tuff is andesite-composition ash which consolidates into welded tuff. Cinders is a reddish color and has the texture of pumice and floats in water. Geyserite is a whitish gray rock that is formed by geysers. Obsidian is a black glossy looking rock. Its main component is glass. Ancient people used it for knives or arrow heads. Basalt is a dark, fine grained rock which contains crystals that are not easy to see. The ocean floor is made mostly of basalt.

Sand Dollars Method: Beach combing fieldtrip Mutsu Bay, Japan Collection: Western Sand Dollars Interpretation: Scientific name: Dendraster excentricus The familiar sand dollar is actually the exoskeleton called a test. It is usually a white, round disk with a five point star design on the top and can be found washed up on the beach. Their mouths are a hole on the bottom center of the exoskeleton. They feed on plants and animals by catching them with their five teeth-like sections. When they’re alive their exoskeletons are covered with fuzzy spines which helps them move. In still waters, they stand up on their sides and are halfway buried in the sand. In rough waters, the sand dollars will try to bury themselves in the sand to avoid being tossed around. They are related to the sea urchin and the sea star. There are many types of sand dollars in all the oceans and examples of these are listed on the display board.

Sources of Information The Nature Company Guides Rocks and Fossils by Arthur B. Busbey III, Robert R. Coenraads, Paul Willis, David Roots. Rocks and Minerals by Chris Pellant. Investigating God’s World, 3 rd edition, A Beka Book Science Series

Display Board and Close Ups

Display Board Con’t…

Collection Labels Sedimentary Rocks What: Magnified Grains Texture: Smooth Size: 1 1\2in.-2in. Where: Shipwreck beach, Mustu Bay, Japan When: Summer of 2006 Collected by: Jacob Urbano What: Chert. Texture: rough; fine grained Color: white, greenish, grayish Size: 6 1\2 in. Where: Misawa Air Base, Japan When: April 23, 2007 Collected by: Jacob Urbano Metamorphic Rocks What: Slate Texture: rough Size: 4 1\2 in. Where: Misawa Air Base, Japan When: April 17, 2007 Collected by: Jacob Urbano What: Green Slate Texture: rough Color: greenish Size: 6 1\2 in. Where: Misawa Air Base, Japan When: April 23, 2007 Collected by: Jacob Urbano

Collection Labels Igneous Rocks What: Pumice Texture: very rough; airy and light Color: whitish, grayish Size: 1-2 in. Where: Miss Veedol Beach, Misawa, Japan When: April 17, 2007 Collected by: Jacob Urbano What: Obsidian Texture: Smooth and glossy Size: 2 in. Color: shiny black Where: My science Kit When: April 19, Collected by: Jacob Urbano What: Rhyolite Texture: Coarse grained Color: Brown, orange, white, black mixed Size: 2 1\4 in. Where: My science kit When: April 23, 2007 Collected by: Jacob Urbano What: Cinders Texture: Coarse Color: Reddish, brown Size: 1 3\4 in. Where: My science kit When: April 23, 2007 Collected by: Jacob Urbano What: Basalt Texture: Bumpy Color: Blackish, grayish Size: 1 3\4 in. Where: My science kit When: April 23, Collected by: Jacob Urbano What: Geyserite Texture: Fine Grained Color: Whitish grayish Size: 1 1/2 inches Where: My science kit When: April 23, 2007 Collected by: Jacob Urbano

Collection Labels What: Welded Tuff Texture: Medium grained Color: pink, purple, white mixed Size: 2 1\4 in. Where: My science kit When: April 23, 2007 Collected by: Jacob Urbano What: Andesite Texture: Fine grained Color: Black Size: 2 in. Where: My science kit When: April 23, 2007 Collected by: Jacob Urbano Shells What: Sand Dollars Texture: fine grained Color: White and gray Size: 2 ½ inches diameter Where: Shipwreck Beach, Mutsu Bay, Japan When: Summer 2006 Collected by: Jacob Urbano

Acknowledgements I want to thank my mom and my older sister for helping and encouraging me with this project.