Geometry and controls on fracturing in a natural fault-bend fold: Rosario field, Maracaibo basin, Venezuela
Journal Article
·
· AAPG Bulletin
OSTI ID:421031
- Exxon Production Research Company, Houston, TX (United States)
- DePauw Univ., Greencastle, IN (United States)
- Exxon Exploration Company, Benmar, Houston, TX (United States)
The Rosario oil field lies between the Perija Mountain front and Lake Maracaibo and produces from fractured Cretaceous carbonates and Tertiary clastics. We interpret the structure as a detached fault-bend fold which ramps through Cretaceous Cogollo and La Luna carbonates and flattens into an upper detachment at the base of the Upper Cretaceous Colon Shale. The structural relief formed primarily during the Mid Miocene and younger. Seismic and well control on the three-dimensional geometry illustrates the effects of (1) lithology and displacement variation on fold geometry, (2) an oblique footwall ramp on hangingwall faulting, and (3) fold curvature on fracturing and hydrocarbon production. Fold geometry at different structural levels is strongly controlled by lithology. Stiff Cogollo and La Luna carbonates exhibit kink-style folding above the upper fault-bend. The weak Colon Shale decouples the faulted carbonates from the concentrically folded Tertiary clastics. Regions of enhanced faulting and fracturing of Cretaceous carbonates are a function of structural position. We observe normal faults in the hangingwall where the strike of the footwall ramp changes from N20{degrees}E to N65{degrees}E. Fold curvature highlights fold hinges, yet distributed faulting is seismically imaged in the forelimb, suggesting that rocks fracture as they migrate through the ramp-upper flat fault-bend. Production rates are higher near the forelimb relative to the flat crestal region.
- OSTI ID:
- 421031
- Report Number(s):
- CONF-9609255--
- Journal Information:
- AAPG Bulletin, Journal Name: AAPG Bulletin Journal Issue: 8 Vol. 80; ISSN 0149-1423; ISSN AABUD2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Clockwise block rotations in the Perija Mountains, Venezuela
Thin-skinned deformation of the Cretaceous and Tertiary sedimentay section of Eastern Offshore Trinidad
Structural styles of the High Atlas mountains, Morocco: Potential hydrocarbon traps in the footwall of thrusts developed from the reactivation of syn-rift normal faults
Conference
·
Sun Jan 31 23:00:00 EST 1993
· AAPG Bulletin (American Association of Petroleum Geologists); (United States)
·
OSTI ID:5939792
Thin-skinned deformation of the Cretaceous and Tertiary sedimentay section of Eastern Offshore Trinidad
Journal Article
·
Thu Aug 01 00:00:00 EDT 1996
· AAPG Bulletin
·
OSTI ID:421079
Structural styles of the High Atlas mountains, Morocco: Potential hydrocarbon traps in the footwall of thrusts developed from the reactivation of syn-rift normal faults
Conference
·
Mon Dec 30 23:00:00 EST 1996
·
OSTI ID:425421