APPARATUS AND METHOD FOR ACQUIRING INFORMATION WHILE DRILLING

摘要

An apparatus and method useful for acquiring information from a subsurfa ce formation penetrated by a wellbore contemplate the use of a tubular body adapted for connection within a drill string disposed in the wellbore. The tubular body is equipped with one or more protuberances (e.g., ribs) defining an expanded axial portion. A probe is carried by the tubular body at or near a first location within the expanded axial portion of the body where the cross-sectional area of the expanded axial portion is a minimum. T he probe is movable between retracted and extended positions. In another aspect, the inventive apparatus may further include a cover releasably-secured about the probe for protectin g the probe while drilling. In a further aspect, the inventive apparatus may include a shearab le backup support carried by the tubular body azimuthally opposite the probe permitting releas e of the apparatus from the wellbore in the event of a failure. In yet another aspect, the prob e is at least partially carried within a debris-clearing channel formed in a protruding portion of t he tubular body to promote fee movement of the probe within the wellbore.