Sandstone fluid inclusions

Shikazono and Shimizu (1987) concluded that Ag contents of gold precipitated from low-salinity fluids is higher than that prediction and the relationship between NAg of gold and salinity of fluid inclusions estimated from freezing temperature data. Therefore, another interpretation is that NAg of gold from shale-hosted deposits is lower than that from sandstone-hosted deposits, because shale is expected to be richer in Cl mainly due to adsorption by clay minerals included in shale than sandstone. 

The Athabasca sedimentary Basin consists of Helikian polycyclic, mature fluvial to marine quartz-rich sandstone deposited in a near-shore shallow shelf environment (Ramaekers 1990) with an estimated filling beginning at about 1700 to 1750 Ma (Armstrong Ramaekers 1985). The estimate maximum thickness of the basin was 5 to 6 km from fluid inclusion studies (Pagel 1975). 

Walderhaug O. (1994) Temperatures of quartz cementation in Jurassic sandstones from the Norwegian continental shelf— evidence from fluid inclusions. J. Sedim. Petrol. 64,311-323. 

Dutkeiwicz A., Rasmussen B., and Buick R. (1998) Oil preserved in fluid inclusions in Archean sandstone. Nature 395, 885-888. 

Walderhaug, O. 1997. Precipitation rates for quartz cement in sandstones determined by fluid-inclusion microthermometry and temperature-history modeling. J. Sedim. Res., in press. 

Such cements occur in weakly compacted sediments and are characterized by low 6 0 values and fluid inclusions with high homogenization temperatures. This mechanism imposes difficulties in recognizing these cements from those formed by recrystallization at increased temperatures, as both mechanisms preserve a high, pre-cement porosity. A few workers (Giroir et al., 1989 Souza et al., 1995) argued that the early emplacement of calcite cement in sandstones of rift basins may take place... 

Few fluid inclusion data have been published for calcite cement in shallow marine sandstones, and homogenization temperatures in calcite may possibly be reset (Barker Goldstein, 1990). However, the measurements reported by Saigal Bjorlykke (1987) are in the range 56-68 C and thus compatible with calcite precipitation prior to deep burial. Finally, the high intergranular volumes found in many calcite-cemented sandstone samples (Table 1) also indicate relatively early calcite precipitation. 

Walderhaug, O. (1990) A fluid inclusion study of quartz-cemented sandstones from offshore mid-Norway— possible evidence for continued quartz cementation during oil emplacement. J. sediment. Petrol., 60, 203-210. 

Diagenetic carbonate cement in reservoir sandstones of the Oseberg Formation (Brent Group) in the Oseberg field, Norwegian North Sea, occurs as disseminated siderite and ankerite, and as massively calcite-cemented intervals. Other diagenetic features include extensive feldspar dissolution and K-feldspar, quartz, kaolinite and dickite cements. Conditions of carbonate cementation are constrained on the basis of textural, geochemical and fluid inclusion evidence. 

Last but not least, Stienstra (1992) cites fluid inclusion microthermometry data by Bone (1989) showing that poikilotopic calcite cements precipitated at temperatures between 85 and 120°C in the Jurassic Adori Sandstone (Fig. 2) of the Tantanna, Marana and Strzelecki Fields (Fig. lA) (Bone, 1989). In these fields, the calcite cement has the same petrographic and isotope characteristics (Fig. 8b) as the calcite in the Namur Sandstone of the Gidgealpa Field. 

McNeil, B., Shaw, H.F. Rankin, A.H. (1995) Diagenesis of the Rotliegend Sandstones in the V-Fields, southern North Sea a fluid inclusion study. In The Geochemistry of Reservoirs (Eds Cubitt, J.M. England, W.A.). Spec. Publ. Geol. Soc. London, 86, 125-139. 

Girard, J.P. Barnes, D.A. (1995) Illitization and paleothermal regimes in the Middle Ordovician St. Peter sandstone, central Michigan Basin K-Ar, oxygen isotope, and fluid inclusion data. Bull. Am. Xsi. Petrol. Geol., 79, 49-69. 

Fig. 4. Petrographic, BSE and colour image characteristics of Tirrawarra Sandstone siderites. (A) Plane-polarized view of the main siderite cement generations that can be distinguished under the optical microscope in this case, which is the exception rather than the rule. SI has a brownish colour, whereas S2 and S3 are clear and colourless. SI is typically engulfed by S2. Note the concentration of fluid inclusions in S2, and the irregular serrated boundary between S2 and S3 (arrow), implying some dissolution of S2 prior to precipitation of S3. Sample Ml-9598, Moorari 1, 2925.5 m.

Fig. 13. Fluid inclusion homogenization temperatures for the middle (S2) and late generations (S3) of the Tirrawarra Sandstone siderites. The fluid inclusions are considered to be of primary origin, and did not experience stretching. S2 formed at much lower temperatures than S3.

Fig. 17. Generalized paragenetic sequence for the Tirrawarra Sandstone in the Fly Lake-Moorari area. Cooper basin. The interpretation is based on the integration of petrographic, isotope and fluid inclusions results. The estimated timing of oil generation and migration is indicated (shaded zone). S1, early generation of siderite cement S2, middle generation of siderite cement S3, late generation of siderite cement D1 and D2, first and second phases of siderite dissolution, respectively.

Fig. 15. Homogenization temperatures (T f) for aqueous fluid inclusions in quartz cement-Norphlet sandstones, Mobile Bay.

Rossi, C., Goldstein, R. H., Ceriani, A. Marfil, R. 2002. Fluid inclusions record thermal and fluid evolution in reservoir sandstones, Khatatba Formation, Western Desert, Egypt a case for fluid injection. American Association of Petroleum Geologists Bulletin, 86, 1773-1799. 

Barclay, S. A., Worden, R. H., Parnell, J., Hall, D. L. Sterner, S. M. 2000. Assessment of fluid contacts and compartmentaHzation in sandstone reservoirs using fluid inclusions an example from the Magnus Oil Field, North Sea. American Association of Petroleum Geologists Bulletin, 84, 489-504. 

George, S. C. et al. 1997. Geochemical comparison of oil-bearing fluid inclusions and produced oil from the Toro sandstone, Papua New Guinea. Organic Geochemistry, 26, 155—173. 

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