They are beginning to test the bioassy by correlating results of the bioassy with the actual effects on fish populations of chemicals found in high concentrations in areas like Kailua's Enchanted Lake. The size of particles that can be imaged above and below the seafloor depends on the length of a sonar system. Unfortunately, the length of a sonar is limited by the space available onboard a ship. Mathematics and advanced engineering techniques make it is possible to improve the resolution of a system, collecting data comparable to that of a much longer sonar. This enhanced system is called a synthetic aperture sonar.
Conventional sonars can penetrate into the subbottom, but only directly under the instrument.
It is therefore able to map shallow seafloor in three-dimensions very quickly and accurately. Beyond the environmental applications, the instrument holds important scientific potential. Edwards wants to peer through sediments to study the relative ages of lava flows on Loihi. Colleague Charles Fletcher hopes to identify drowned reefs obscured by ocean sediment. Tests of the prototype instrument have been encouraging, detecting gas cylinders buried two feet below the seabed.