Use of several types of production logs in combination can provide important information, often quite cost effectively, for diagnosing a gas kick encountered during drilling. An example is discussed below. During the coring of a gas sand at 15,000 ft, a pressure kick occurred, gas pressure was then lost at the surface, and mud was added periodically to keep the drillpipe full. These logs were run to identify the flow path of a likely underground blowout. At 15,000 ft, the noise log (Figure 1a) exhibits a nearly "dead-well" noise level, indicating no activity (i.e., no fluid movement).