2005 LEXUS LX470 Fuelpropulsion System Problems

VEHICLE WAS TOPPED OF WITH A FULL TANK OF GAS PRIOR TO GOING ON A OFF ROAD DRIVE. THE VEHICLE WAS DRIVEN MODESTLY UP SILVER CANYON TRAIL WITH NO MECHANICAL ISSUES UNTIL GAS FUMES BECAME APPARENT. I INITIALLY THOUGHT THE RIG WAS RUNNING RICH IN FUEL AND CONTINUED THE CLIMB. THEN ON A BREAK I NOTICED GAS SPEWING FROM THE VEHICLE'S GAS CAP. THERE WAS A TREMENDOUS PRESSURE BUILD UP. ONCE I REACHED THE TOP OF THE TRAIL THE ISSUE WAS PHOTOGRAPHED AND RECORDED. I WAITED TILL THE SPEWING OF GAS STOPPED THEN DROVE BACK DOWN. THE ISSUE WAS BROUGHT TO LEXUS KEARNY MESA AND BECAUSE THE ISSUE COULD NOT BE RECREATED NO REPAIRS WERE MADE. THE CONDITIONS WERE NOT PROPERLY RECREATED TO MAKE THE PROBLEM REAPPEAR. MY CONCERN IS POSSIBLE GAS IGNITION AND EXPLOSION.