Photo/IllutrationA colorful geological map is projected onto a precision miniature model of the Japanese islands at the Geological Museum in Tsukuba, Ibaraki Prefecture. (Shinichi Mishima)

TSUKUBA, Ibaraki Prefecture--A museum here spent about 25 million yen ($234,000) for a new showpiece that offers visitors a three-dimensional geological map of Japan in 194 colors.

The Geological Museum of the National Institute of Advanced Industrial Science and Technology replaced a miniature model that had been on exhibit for 38 years with the new display on March 1.

Five computer-controlled projectors throw a geological map image onto the new blank white model of the archipelago.

The model, which measures about 9 meters in length, has a scale of about 1:340,000.

The projected map shows, for example, that the Median Tectonic Line, which cuts across the Japanese archipelago, defines a key geological boundary.

Areas north of the line are mainly composed of igneous rocks, shown in reddish colors, that were formed when the Japanese islands were connected by land with the Eurasian continent.

Areas south of the line largely consist of sedimentary rocks, in greenish hues, that were generated on the Pacific seabed.

The projectors can also throw a topographic map or a satellite image, instead of the geological map, onto the blank model.

Superimposing diagrams of railways, roads, rivers and other features on top of one of those patterns allows the viewer to see, for example, what geological features underlie expressways and Shinkansen tracks.

“We hope to further increase the number of available projection image options so visitors will understand the links between geology and our society,” said Osamu Fujiwara, the 50-year-old director of the Geological Museum.

The museum has more than 2,000 exhibits, including minerals and fossils from around Japan.

Admission is free.