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Research about Gulf Of Mexico

Source-linked reports with geographic coverage including Gulf Of Mexico.

64 records · Page 4Linked to original sources

Growth in conventional fields in high-cost areas: A case study

Exploration managers commonly base future drilling decisions on past experience in an area. To do this well, they should consider both discovered and undiscovered resources to characterize total future potential. Discovery-size estimates should be adjusted to account for future field growth; otherwise, the relative efficiency of recent exploration will be undervalued. This study models and projects field growth for pre-1997 discoveries in the U.S. Federal Gulf of Mexico (GOM) Outer Continental Shelf (OCS). Projected additions to reserves for these fields from field growth through 2020 are 5.2 billion bbl of oil and 46 Tcfg. Projections include growth associated with sizable new oil discoveries in deepwater areas and initial reserve additions from new subsalt plays discovered through 1996. This article focuses on the U.S. GOM because it has produced longer than other worldwide offshore areas. Its field-growth profile may be prototypical of other offshore provinces such as the North Sea, Scotian Shelf and deepwater Angola, as well as high-cost onshore areas.

Gulf Of Mexico

Factors controlling heavy-mineral variations on the South Texas outer continental shelf, Gulf of Mexico

Heavy-mineral distribution on the outer continental shelf off the southern coast of Texas shows regional variability induced by provenance and local variability reflecting genetic differences in sea-floor sediments. Q-mode factor analysis showed that three suites of heavy minerals are present. The southern ancestral Rio Grande delta sediments contain a distinct opaque-pyroxene-garnet suite, whereas the northern ancestral Brazes-Colorado delta sediments contain a tourmaline-green hornblende suite. An interdelta region contains a heavy mineral suite that is mixed owing to contributions from both ancestral deltas. Analysis of variance, correlation, and regression methods indicate that heavy-mineral variations in each sedimentary province have been significantly influenced by hydraulic fractionation by size, shape, and density, and by a selective chemical decomposition of unstable minerals. These factors have operated at varying degrees on the relict, palimpsest, and modern sediment populations of the sedimentary provinces since the end of Pleistocene time. The differential effects of these processes on the sediments have resulted in local variations that contribute to the total mineralogical variability. A comparison of the heavy mineral suites of the modern and relict Rio Grande delta sediments, which are derived from a common provenance, also shows mineral variations resulting from factors other than provenance.

Texas

Interstitial water studies on small core samples, Deep Sea Drilling Project: Leg 10

Leg 10 interstitial water analyses provide new indications of the distribution of rock salt beneath the floor of the Gulf of Mexico, both confirming areas previously indicated to be underlain by salt bodies and extending evidence of salt distribution to seismically featureless areas in the Sigsbee Knolls trend and Isthmian Embayment. The criterion for presence of salt at depth is a consistent increase in interstitial salinity and chlorinity with depth. Site 86, on the northern margin of the Yucatan Platform, provided no evidence of salt at depth. Thus, our data tend to rule out the suggestion of Antoine and Bryant (1969) that the Sigsbee Knolls salt was squeezed out from beneath the Yucatan Scarp. Cores from Sites 90 and 91, in the central Sigsbee Deep, were not obtained from a great enough depth to yield definite evidence for the presence of buried salt. Site 86, on the northern margin of the Yucatan Platform, provided no evidence of salt at depth. Thus, our data tend to rule out the suggestion of Antoine and Bryant (1969) that the Sigsbee Knolls salt was squeezed out from beneath the Yucatan Scarp. Cores from Sites 90 and 91, in the central Sigsbee Deep, were not obtained from a great enough depth to yield definite evidence for the presence of buried salt.

Initial reports of the Deep Sea Drilling Project