D.N. Kozlov, R.V. Zharkov

Institute of Marine Geology and Geophysics FEB RAS, Yuzhno-Sakhalinsk, 693022

The paper provides the results from a bathymetric survey of the intercaldera lakes Goryachee and Kipyashee (Golovnin Caldera, Kunashir Island) and the Biryuzovoye Lake (Zavaritskiy Caldera, Simushir Island). Overviews are given for the calderas, the last stages of their eruptive activity, and their present state. The paper introduces and describes in detail a modern method for conversion data from the echo shooting into bathymetrical schemes. Keywords: phreatic explosion, caldera, lake, sonar, bathymetric scheme, gas-hydrotherms.