Method for correcting lost circulation of drilling fluids

Claim 1

IN THE PROCESS OF DRILLING A WELL BORE IN THE GROUND WHEREIN A DRILLING FLUID IS PUMPED FROM THE SURFACE OF THE GROUND THROUGH SAID WELL BORE AND THENCE BACK TO THE SURFACE OF THE GROUND AND LOST CIRCULATION OF SAID DRILLING FLUID IS ENCOUNTERED BY REASON OF SAID DRILLING FLUID ENTERING A LOST CIRCULATION ZONE WITHIN SAID WELL BORE, SAID LOST CIRCULATION ZONE CONTAINING WATER, THE IMPROVEMENT IN CORRECTING LOST CIRCULATION OF SAID DRILLING FLUID COMPRISING DISCONTINUING PUMPING OF SAID DRILLING FLUID FROM THE SURFACE OF THE GROUND THROUGH SAID WELL BORE, PUMPING INTO SAID WELL BORE TO CONTACT SAID LOST CIRCULATION ZONE OIL CONTAINING A FIRST AGENT WHICH WILL ASSIST IN STABILIZATION OF AN EMULSION AND ALSO CONTAINING A SECOND AGENT WHICH WILL ASSIST IN STABILIZATION OF AN EMULSION, SAID SECOND AGENT CONSISTING OF BLOWN ASPHALT, WHEREBY SAID OIL WILL ADMIX WITH SAID WATER IN SAID LOST CIRCULATION ZONE AND FORM AN EMULSION THEREIN AND SAID BLOWN ASPHALT WILL FLOCCULATE, WHICH EMULSION WILL ADHERE TO THE WALLS OF THE INTERSTICES OF SAID LOST CIRCULATION ZONE AND WHICH FLOCCULATED BLOWN ASPHALT WILLLADHERE WITH THE EMULSION TO THE WALLS OF THE INTERSTICES OF SAID LOST CIRCULATION ZONE TO FORM A MATTING THEREIN, THEREAFTER PUMPING INTO SAID WELL BORE TO CONTACT SAID LOST CIRCULATION ZONE A SUSPENSION OF SHREDDED LEATHER IN A LIQUID WHEREBY SAID SHREDDED LEATHER WILL ADHERE TO SAID MATTING WITHIN SAID LOST CIRCULATION ZONE TO FORM WITHIN SAID LOST CIRCULATION ZONE A BARRIER TO THE ENTRY OF DRILLING FLUID, AND THEREAFTER PUMPING DRILLING FLUID FROM THE SURFACE OF THE GROUND THROUGH SAID WELL BORE.