DOWNHOLE MEASUREMENT OF SUBSTANCES IN FORMATIONS WHILE DRILLING

• Main Authors: STEPHENSON KENNETH E, TARVIN JEFFREY A
• Format: Patent
• Language: English
• Published: 15.05.2008
• Subjects: COLORIMETRY; DETECTING MASSES OR OBJECTS; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT,POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRA-RED,VISIBLE OR ULTRA-VIOLET LIGHT; MEASURING; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PHYSICS; RADIATION PYROMETRY; TESTING

A method and apparatus for measuring a substance in formations surrounding an earth borehole being drilled with a drill bit at the end of a drill string, using drilling fluid that flows downward through the drill string, exits through the drill bit entrained with drilled earth formation cuttings, and returns toward the earth's surface in the annulus between the drill string and the borehole, the method including the following steps: waiting for any of the substance that is dissolved in the drilling fluid to be substantially in equilibrium with any of the substance in the earth formation cuttings; and then measuring, downhole, the substance dissolved in the drilling fluid.