The Inter-Relationships of Scales of Heterogeneity in Subsurface, Deep Water E&P Projects—Lessons Learned from the Mount Messenger Formation (Miocene), Taranaki Basin, New Zealand
Published:December 01, 2000
J. L. Coleman, Jr., G. H. Browne, P. R. King, R. M. Slatt, R. J. Spang, E. T. Williams, G. R. Clemenceau, 2000. "The Inter-Relationships of Scales of Heterogeneity in Subsurface, Deep Water E&P Projects—Lessons Learned from the Mount Messenger Formation (Miocene), Taranaki Basin, New Zealand", Deep-Water Reservoirs of the World, Paul Weimer
Download citation file:
Sea cliff exposures, conventional and high resolution seismic profiles, conventional oil and gas field boreholes, and shallow behind-outcrop core holes along the west coast of the Taranaki Basin, North Island, New Zealand, afford an excellent opportunity to examine the inter-relationships of scales of heterogeneity within slope channel-levee-overbank and toe-of-slope deep water sediments. Here, the Taranaki sea cliffs, are up to 240 m high and exhibit over 25 km of nearly continuous exposure. Across the spectrum from seismic profile to microscopic and instrumental analysis, detectable features that affect reservoir heterogeneity range across at least 13 orders of magnitude from greater than 104 m to 10-9 m.
Using the exposures along the Taranaki Coast, it is possible to assess the extent and detectability of the various scales of lithologic heterogeneity and to estimate their effects on analogous intervals in the subsurface. Bed/bedset heterogeneity ratios (calculated as vertical distance divided by horizontal distance of a given parameter), as detected by the tools mentioned above, cluster in two domains. Because of their limited radius of investigation, borehole logs have ratios between 100 and 10-1, whereas outcrop, seismic, and log profiles, which are based on a horizontal arrangement of data, generally show ratios between 10-1 to 10-3. Because of their design limitations and strengths, each of the tools sees a different scale of lithologic or bedform heterogeneity.
Data sets such as that available from the Taranaki cliffs section are invaluable for constraining estimates of reservoir heterogeneity in subsurface models.