METHOD AND APPARATUS FOR MONITORING THE POSITION AND MOVEMENT PROGRESS OF THE FLAME FRONT IN AN UNDERGROUND COMBUSTION OPERATION

摘要

ABSTRACT OF THE DISCLOSUREAn underground combustion operation in whichcombustible material, in a selected geologic forma-tion at a selected depth is burned by forcing airunder pressure down a first well into the formation,and collecting products of combustion at a secondwell, a selected distance away from the first well.The overburden above the formation is supported, inpart, by the combustible material, which might beviscous oil, tar, etc. This material is ignited atthe first well and a flame front is formed which burnsin the form of a circular front, which moves radiallyoutwardly as a function of time and the rate of airsupply. A plurality of electronic tilt meters arepositioned at or near the surface of the earth, inat least one linear array directed along the radiusfrom the first well to the second well. Combustionair is provided and the outputs of the tilt meters areamplified and recorded as a function of time. Asthe flame front progresses, the overburden behindthe front will slump, which will be reflected by acorresponding slump and tilting of the earth surface,which will be reflected in the corresponding readingsof the tilt meters.