Environmentalists are in Federal Court hoping to block seismic testing that will send high decibel blasts into the ocean off Vancouver Island, possibly harming whales and other marine life in the area.

A U.S. research team wants to investigate the tectonic plates making up the ocean sub-floor around the Endeavour Hydrothermal Vents marine protected area, 250 kilometres west of Vancouver Island.

Ecojustice lawyer Lara Tessaro says environmentalists want a court injunction barring Canadian authorities from allowing a research ship to map the plates by bombarding them with sound waves.

Tessaro says she also wants the court to spell out the government's obligations when it comes to protecting marine mammals from potentially harmful seismic testing.