Hydrocarbon systems in the southwest Maracaibo Basin, Colombia

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · AAPG Bulletin

OSTI ID:421236

Yurewicz, D A; Advocate, D M; Sequeira, J J; McDermott, V J; Young, R H; Wellman, P C ^[1]

---

1. Exxon Exploration Co., Houston, TX (United States); and others

Multiple hydrocarbon systems are recognized in the Colombian portion of the Maracaibo Basin (Catatumbo subbasin). Hydrocarbons, trapped in wrench controlled, faulted anticlines, were generated from two different source horizons, in two distinct source kitchens, and migrated along different pathways into Cretaceous and Tertiary reservoirs. Cretaceous reservoirs are shallow-marine sandstones and limestones characterized by low matrix porosity and permeability. They are separated from Tertiary reservoirs by a thick shale seal that limited cross-stratal migration. Tertiary reservoirs are fluvial-deltaic sandstones with good to excellent porosities and permeabilities. Geochemical data suggest the presence of two oil families. Family 1 oils were sourced locally from Cretaceous marine shales and limestones and account for most of the oil in Tertiary and Cretaceous reservoirs. Family 2 oils are only present in Tertiary reservoirs in the southern part of the subbasin, and are interpreted to be sourced from Paleocene terrestrial shales and coals. Two distinct migration systems operated to fill Catatumbo traps. Family 1 oils migrated from local Cretaceous source beds along fractures and faults that developed concurrently with trap formation. Family 2 oils were sourced from outside the Catatumbo subbasin. Maturation data and burial history modelling indicate that Paleocene rocks are immature in the Catatumbo subbasin. Maturation levels increase westward into the Maracaibo Basin and along the axis of the North Andean foredeep. The proximity of Rio Zulia Field to the North Andean foredeep, and lack of Tertiary-sourced oils in other Catatumbo fields suggest that the North Andean foredeep is the primary source for these oils.

• OSTI ID: 421236
• 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

Related Subjects

02 PETROLEUM
COLOMBIA
EXPLORATION
FLUID FLOW
MATURATION
ORIGIN
PETROLEUM
PETROLEUM DEPOSITS
SOURCE ROCKS
STRATIGRAPHY