Large cracks believed to have been caused by the seismic force of the March 11 Great East Japan Earthquake have been confirmed in photographs and video footage of the seabed.
Large cracks believed to have been caused by the seismic force of the March 11 Great East Japan Earthquake have been confirmed in photographs and video footage of the seabed.
The images, taken by a manned deep-sea submersible around the epicenter of the quake that left more than 15,000 people dead, were released Aug. 15 by an independent administrative agency on marine technology development.
On the sea bottom 5,351 meters below the surface, a large crack?more than 80 meters long, 1 meter wide and 1 meter deep?was detected by the Japan Agency for Marine-Earth Science and Technology.
At another point 3,218 meters below the surface, a crack measuring several tens of meters in length and 20 centimeters in width was found.
JAMSTEC said the cracks were likely formed by the March 11 quake, its aftershocks or unrelated quakes after March 11.
The agency and other researchers investigated three locations near the epicenter aboard the manned research submersible Shinkai 6500 from July 30 to Aug. 14. During the investigation, the research team also found a group of calyptogena phaseoliformis, a type of clam that absorbs hydrogen sulfide?a substance made of bacteria proliferated by methane from cracks on the sea floor.