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- W1981910776 abstract "Generally, the history of past sub-surface fluid movements is difficult to reconstruct. However, the composition of oil-field waters characterizes the origins and mixing processes that allow such a reconstruction. We have investigated present-day formation waters from Brent Group sedimentary rocks of the Oseberg Field in order to assess both their geochemical variations, and their origin(s). Water samples (sampled at the separator) produced from immediately above the oil–water contact and from the aquifer (water-saturated zone below the oil–water contact) were taken from 11 wells across the field. In addition, 3 trace water samples were extracted from oil produced from higher up in the oil column. The water samples were analysed for their chemical components and isotopic compositions. Conservative tracers such as Cl, Br, δD, and δ18O were used to evaluate the origin of the waters. All formation waters can be characterised as Na–Cl-brines. The separator samples are of aquifer origin, indicating that aquifer water, drawn up by the pressure reduction near the well, is produced from the lower few tens of metres of the oil-zone. By defining plausible endmembers, the waters can be described as mixtures of seawater (60–90%), meteoric water (10–30%), evaporated seawater (primary brines) (3–5%), and possibly waters which have dissolved evaporites (secondary brines). Alternatively, using multidimensional scaling, the waters can be described as mixtures of only 3 endmembers without presupposing their compositions. In fact, they are seawater, very dilute brine, and a secondary brine (confirming the power of this approach). Meteoric water was introduced into the reservoir during the end-Brent and early-Cretaceous periods of emergence and erosion, and partially replaced the marine pore fluids. Lateral chemical variations across the Oseberg Field are extremely small. The waters from closer to the erosion surfaces show slightly stronger meteoric water isotopic signatures. The primary and secondary brines are believed to come from Permian and Triassic evaporitic rocks in the deeply buried Viking Graben to the west, and to have been modified by water–rock interactions along their migration path. These primary basinal brines have not been detected in the oil–zone waters, suggesting that the brines entered the reservoir after the main phase of oil-migration. There are indications that these external fluids were introduced into the reservoir along faults. Present-day aquifer waters are mixtures of waters from different origins and hardly vary at a field-scale. They are different in composition to the water trapped in the present oil-zone. One of the oil-zone samples is a very dilute brine. It is thought to represent a simple mixture of seawater and meteoric water. Due to oil-emplacement, this geochemical signature was preserved in the waters trapped within the oil-zone. Another oil-zone water shows a very similar chemical signature to the aquifer waters, but the chlorine isotopic signature is similar to that of the dilute oil-zone water. This water is interpreted to represent a palaeo-aquifer water. That is, it was within the aquifer zone in the past, but was trapped by subsequent emplacement of more oil. These vertical differences can be explained by two features: (i) emergence of the Brent Group sedimentary rocks in the Early Cretaceous allowed ingress of meteoric water; (ii) subsequent rapid burial of Viking Graben rocks caused migration of petroleum and aqueous fluids into the adjacent, less deeply buried Oseberg Field." @default.
- W1981910776 created "2016-06-24" @default.
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- W1981910776 date "2001-05-01" @default.
- W1981910776 modified "2023-09-24" @default.
- W1981910776 title "Palaeohydrodynamics of fluids in the Brent Group (Oseberg Field, Norwegian North Sea) from chemical and isotopic compositions of formation waters" @default.
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- W1981910776 cites W1968448747 @default.
- W1981910776 cites W1969340698 @default.
- W1981910776 cites W1973192023 @default.
- W1981910776 cites W1975194082 @default.
- W1981910776 cites W1976620802 @default.
- W1981910776 cites W1976846270 @default.
- W1981910776 cites W1977472551 @default.
- W1981910776 cites W1978142032 @default.
- W1981910776 cites W1988378253 @default.
- W1981910776 cites W1993041545 @default.
- W1981910776 cites W1998933135 @default.
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- W1981910776 cites W2014945279 @default.
- W1981910776 cites W2021730831 @default.
- W1981910776 cites W2026229574 @default.
- W1981910776 cites W2028712559 @default.
- W1981910776 cites W2039248536 @default.
- W1981910776 cites W2045645213 @default.
- W1981910776 cites W2049105121 @default.
- W1981910776 cites W2051820263 @default.
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- W1981910776 cites W2061442059 @default.
- W1981910776 cites W2062208402 @default.
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- W1981910776 cites W2066532548 @default.
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- W1981910776 cites W2131867281 @default.
- W1981910776 cites W2137978035 @default.
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- W1981910776 doi "https://doi.org/10.1016/s0883-2927(00)00057-3" @default.
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