In the same way that the number of rings in a tree can tell us its age, the characteristics of rocks such as breccia can tell us about the history of a region. The breccia around Ichinokawa Mine are of particular interest, as the mine is located south of the Median Tectonic Line. Researchers uncovered how breccia can provide valuable evidence to estimate the energy of past earthquakes in the area.
In the same way that the number of rings in a tree can tell us its age, the characteristics of rocks such as breccia can tell us about the history of a region. The Ichinokawa breccia are unique in that they can retain a record of the frequent seismic activity that occurs along the Median Tectonic Line . The MTL is a fault line that extends approximately 1000 kilometres along the southwest region of Japan. This makes the breccia formed in this area to be of particular interest to researchers.
Many factors were assessed in order to calculate the energy and nature of the earthquake. For example, close observation of breccia revealed the formation of carbonates such as CaMg estimated to be 5.8-8.3 Mw.