Thomas L Ragan

US Patent:

62017640, Mar 13, 2001

Filed:

Oct 31, 1997

Appl. No.:

8/962125

Inventors:

Charles Geoffrey Rice - Sugar Land TX
Paul Ellington Carroll - Houston TX
Thomas Glen Ragan - Sugar Land TX

Assignee:

Input/Output, Inc. - Stafford TX

International Classification:

G01V 138

US Classification:

367 21

Abstract:

A method and an apparatus are provided for matching the response of hydrophones 22 to the response of geophones 24 and significantly reducing response variations between hydrophones caused by inherent characteristics. The method includes the steps of determining a capacitance 66 for each of the hydrophones 22 in an operating environment, configuring a filter 36 based on the capacitance 66, and modifying a response of a channel of the hydrophone 22 using the filter 36. The apparatus includes an acquisition unit 20 having a geophone 24 and a hydrophone 22, a recording unit 30, a processing unit 31 and a filter 36 for correcting for variation between hydrophones 22 and changing a first order low frequency response of the hydrophone 22 to appear like a second order response like that of the geophone 24.