The connection between natural gas hydrate and bottom‐simulating reflectors

• Published in: Geophysical research letters Vol. 43; no. 13; pp. 7044 - 7051
• Main Authors: Majumdar, Urmi, Cook, Ann E., Shedd, William, Frye, Matthew
• Format: Journal Article
• Language: English
• Published: Washington John Wiley & Sons, Inc 16-07-2016; American Geophysical Union
• Subjects: Accumulations; Area; bottom-simulating reflector; Data; Datasets; Drilling; Electrical resistivity; gas hydrate; Gas hydrates; GEOSCIENCES; Gulf of Mexico; Hydrates; Identification; Marine sediments; Natural gas; Natural gas hydrates; Reflectors; Sediment; Sediments; Seismic data; Seismic studies; Seismological data; Shear strength; Well logs; Wells; ASW, Mexico Gulf
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2016GL069443

Bottom‐simulating reflectors (BSRs) on marine seismic data are commonly used to identify the presence of natural gas hydrate in marine sediments, although the exact relationship between gas hydrate and BSRs is undefined. To clarify this relationship we compile a data set of probable gas hydrate occurrence as appraised from well logs of 788 industry wells in the northern Gulf of Mexico. We combine the well log data set with a data set of BSR distribution in the same area identified from 3‐D seismic data. We find that a BSR increases the chances of finding gas hydrate by 2.6 times as opposed to drilling outside a BSR and that the wells within a BSR also contain thicker and higher resistivity hydrate accumulations. Even so, over half of the wells drilled through BSRs have no detectable gas hydrate accumulations and gas hydrate occurrences and BSRs do not coincide in most cases.
Key Points
We quantify the relationship between gas hydrate and bottom‐simulating reflectors
Bottom‐simulating reflectors improve the chances of finding gas hydrate by 2.6 times
Gas hydrate and bottom‐simulating reflectors, however, do not always coincide