How do scientists measure the depth of the volcano?

Scientists aboard the March 2002 and March 2003 NOAA research cruises of Kick-‘em-Jenny used SeaBeam technology to measure the depth of the volcano and conduct bathymetric surveys of Kick-’em-Jenny. Bathymetry essentially means “submarine topography”, and a bathymetric survey refers to a series of sophisticated depth soundings over a particular area to determine the depth and shape of the sea floor. Signals are transmitted from the ship down to a specific point beneath the ship and the return speed of these signals is used to calculate the depth. During the recent cruises, scientists sent millions of signals to various points on Kick-’em-Jenny and all of these points, when put together, were used to form a detailed bathymetric map of the volcano. The early surveys over Kick-‘em-Jenny conducted in the 1960s used much less sophisticated technology, and it was only possible to obtain the depth to a few points on the volcano.