Petroleum systems of the Middle Magdalena Valley, Colombia

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

OSTI ID:421149

Mora, C; Cordoba, F; Luna, O; Sarmiento, L F; Rangel, A ^[1]

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1. and others

The petroleum systems of the Middle Magdalena Valley include 29 oil fields and numerous oil seeps with recoverable reserves of 3 billion barrels of oil. Based on API gravity, sulfur content, pristane/phytane index, carbon isotopic ratios of the saturated and aromatic hydrocarbon fractions, and biomarkers, at least two oil families occur within this province. Each oil family covers a different area. Based on stratigraphic occurrence, one oil family originated from the Tablazo Formation of Aptian age while the other oil family originated from the La Luna Formation of Cenomanian to Santonian age. Both of these rock units have high organic carbon contents and hydrogen indices indicative of petroleum source rocks. The primary reservoir rocks are the Tertiary sandstones of the La Paz, Esmeraldas, Mugrosa, and Colorado Formations. The La Cira Shale, a regional seal rock, is the uppermost part the Colorado Formation. Secondary reservoirs are limestones of the Tablazo, Rosablanca, and La Luna formations, and sandstones of the Lisama and Umir Formations. An Eocene unconformity separates the primary reservoir rocks above from the secondary reservoir rocks and active source rocks below. This unconformity places the primary reservoir rocks in angular discordance with the underlying active source rock intervals, forming the main plumbing system for migrating petroleum. Traps are related to pre-Andean and Andean folding and faulting. Overburden rocks are Cretaceous marine, Paleocene transitional, and Eocene-Pleistocene nonmarine sedimentary rocks. Thermal data and modeling indicates that the thermal history of the source rock intervals was sufficient to generate hydrocarbons during late Tertiary time.

• OSTI ID: 421149
• 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
FLUID FLOW
MATURATION
OIL FIELDS
ORIGIN
PETROLEUM
RESERVES
RESERVOIR ROCK
SOURCE ROCKS
STRATIGRAPHY