The Tosashimizu Geopark Plan
The city of Tosashimizu spreads out on both sides of Cape Ashizuri in southern Kochi Prefecture. It occupies land formed by tectonic and magma-related activity millions of years ago, and has a mild climate thanks to the warm Kuroshio, also known as the Japan Current, which flows north from the East China Sea along Japan’s Pacific coast. This combination of tectonic and oceanic forces gave birth to the seaside landscape and ecosystems that have provided a livelihood for the local people, who have practiced fishing and agriculture here for centuries. Tosashimizu works to conserve and highlight this unique natural environment and the seaside lifestyles it supports, and to pass the legacy on to future generations.
The Geological Origins of Tosashimizu
The land that is now occupied by Tosashimizu was formed when deep-sea sediment was pushed upward by the interplay of tectonic plates over tens of millions of years. In addition, the geological strata in the Tatsukushi and Ashizuri areas bear marks from 15 to 20 million years ago, when land at the edge of mainland Asia broke off into the ocean and formed the Japanese archipelago. The land that was fashioned in this great upheaval continues to be shaped by the movement of tectonic plates, as well as by weathering and erosion.