1. IN CORING TOOL FOR OBTAINING A CORE FROM EARTHEN FORMATION FROM AN UNDERWATER LOCATION, THE COMBINATION OF: A VERTICALLY ORIENTED ELASTIC STEM, AT LEAST THE LOWER PORTION OF WHICH COMPRISES A CORE TUBE, A UNITARY POWER UNIT STRUCTURE AT THE UPPER END OF SAID STEM, A SONIC FREQUENCY ELASTIC WAVE GENERATOR IN SAID POWER UNIT ACOUSTICALLY COUPLED TO SAID STEM AND OPERABLE AT A LONGITUDINAL RESONANT FREQUENCY OF SAID STEM SO AS TO ESTABLISH A LONGIDUTINAL ELASTIC STANDING WAVE VIBRATION IN SAID STEM, MOTOR MEANS IN SAID POWER UNIT STRUCTURE DRIVINGLY CONNECTED TO SAID WAVE GENERATOR, AND A CABLE SUSPENSION SYSTEM WITH TENSION CONTROL SUPPORTING SAID POWER UNIT STRUCTURE AND SAID STEM UNDER WATER IN A VERTICALLY HANGING POSITION, WITH THE CORE TUBE PORTION OF SAID STEM ACOUSTICALLY COUPLED TO SAID UNDERWATER EARTHEN FORMATION WITH AN ACOUSTIC COUPLING BIAS WHEREBY SAID FORMATION HAS SONIC ENERGY TRANSMITTED THERETHROUGH AS IT FLOWS AS A CORE INTO SAID CORE TUBE.