Changes

==Combining BHGM with tomography==

==Combining BHGM with tomography==

[[file:applying-gravity-in-petroleum-exploration_fig15-17.png|thumb|{{figure number|6}}After <ref name=ch15r12>van Popta, J., Heywood, J., M., T., Adams, S., J., Bostock, D., R., 1990, Use of borehole gravimetry for reservoir characterisation and fluid saturation monitoring: Expanded Abstracts, SPE Europec 90 conference, p. 151–160. Use of time-lapsed borehole gravity logging to monitor fluid movement away from the borehole.</ref>. Copyright: SPE.]]

[[file:applying-gravity-in-petroleum-exploration_fig15-16.jpg|left|thumb|{{figure number|5}}After .<ref name=ch15r7>Lines, L., R., Tan, H., Treitel, S., 1991, Velocity and density imaging between boreholes: CSEG Recorder, vol. 16, no. 6, p. 9–14. A unique case study that integrates borehole gravity with the processing and interpretation of cross-well tomography.</ref> Copyright: CSEG Recorder.]]

Between-well imaging jointly uses borehole gravity with seismic tomography. Because of the unique distant resolution capabilities of borehole gravity, these data provide a useful integrating tool at the seismic wavelet scale. In the Gulf of Mexico example shown in [[:file:applying-gravity-in-petroleum-exploration_fig15-16.jpg|Figure 5]], Amoco used its borehole gravity log to help interpret a detailed cross-borehole seismic tomography image. The two wells were located less than [[length::250 ft]] apart. Two faults, Fl and F2, are seen in both data sets, and excellent correlations are made of various sands labeled M5, M6, M8, M9, M10, and M10A. Note that the well on the left encountered more pay sands than the well on right. Also note that the M6 sand is missing in the well on the left. The between-well structural and stratigraphic changes in only [[length::250 ft]] can be understood by combining the interpretations of the two comparable distant imaging tools: borehole gravity and seismic tomography.

Between-well imaging jointly uses borehole gravity with seismic tomography. Because of the unique distant resolution capabilities of borehole gravity, these data provide a useful integrating tool at the seismic wavelet scale. In the Gulf of Mexico example shown in [[:file:applying-gravity-in-petroleum-exploration_fig15-16.jpg|Figure 5]], Amoco used its borehole gravity log to help interpret a detailed cross-borehole seismic tomography image. The two wells were located less than [[length::250 ft]] apart. Two faults, Fl and F2, are seen in both data sets, and excellent correlations are made of various sands labeled M5, M6, M8, M9, M10, and M10A. Note that the well on the left encountered more pay sands than the well on right. Also note that the M6 sand is missing in the well on the left. The between-well structural and stratigraphic changes in only [[length::250 ft]] can be understood by combining the interpretations of the two comparable distant imaging tools: borehole gravity and seismic tomography.