Hydrocarbon-Induced Diagenetic Aureoles (HIDA): Indicators of deeper leaky reservoirs

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · AAPG Bulletin

OSTI ID:86609

Al-Shaieb, Z; Cairns, J; Puckette, J ^[1]

---

1. Oklahoma State Univ., Stillwater, OK (United States)

The Permian redbeds that overlie some giant oil fields in southwestern and south-central Oklahoma have undergone extensive mineralogical and chemical diagenesis. The diagenetic minerals occur within a distinctly zoned aureole that delineates the position of the oil field. The geometries of the aureoles strongly reflect the major structural elements that controlled emplacement of hydrocarbons in the underlying rocks . Calcite, ferroan calcite, manganese-rich calcite, dolomite, ankerite, pyrite and native sulfur are the major diagenetic minerals. The innermost zone of the aureole (zone 1) is characterized by abundant carbonate cementation and generally coincides with a major fault system. Zone 2 is composed of altered (bleached) redbeds with minimal calcite cement. Pyrite cement (zone 3) is commonly associated with the carbonate-cemented zones and is disseminated in some bleached sandstones. Zone 4 represents the unaltered red beds. {delta}C{sup 13} values of carbonate cements indicate 3 major sources of carbon: (1) an organic source with {delta}C{sup 13} values approximately -32 {per_thousand} vs. PDB, (2) a freshwater source with an average {delta}C{sup 13} value of -8.0 {+-} 3 {per_thousand}, and (3) a hybrid source (freshwater and organic). {delta}S{sup 34} values of pyrite average 6.1{per_thousand} and range from -9 {per_thousand} to +16 {per_thousand}. Leakage from deeper hydrocarbon-bearing reservoirs formed shallow petroleum accumulations and contributed to the alteration of the redbeds. Faults were the likely conduits that carried leaked hydrocarbons to the shallow rocks. The development of the oil fields with alteration halos indicate that the HIDA can be used to identify potential shallow oil and deep gas accumulations. Therefore, the HIDA concept can be used in the exploration for oil and gas, especially in faulted structural settings.

• OSTI ID: 86609
• Report Number(s): CONF-9506190--
• Journal Information: AAPG Bulletin, Journal Name: AAPG Bulletin Journal Issue: 6 Vol. 79; ISSN 0149-1423; ISSN AABUD2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
DIAGENESIS
EXPLORATION
HYDROTHERMAL ALTERATION
NATURAL GAS DEPOSITS
OKLAHOMA
PERMIAN PERIOD
PETROLEUM DEPOSITS
RESERVOIR ROCK