Burial, sedimentary basins

Land L. S. (1997) Mass transfer during burial diagenesis in the Gulf of Mexico sedimentary basin an overview. Special Publication—SEPM (Society for Sedimentary Geology) 57, 29-39. 

Land L. S. (1997) Mass-transfer during burial diagenesis in the Gulf of Mexico sedimentary basin. In Basin-wide Diagenetic Patterns, SEPM Special Publication 57 (eds. I. Montanez, J. M. Gregg, and K. L. Shelton). Society for Sedimentary Geology (SEPM), Tulsa, OK, pp. 29-39. 

LandL. S., MackL. E., Milliken K. L., andLynchF. L. (1997) Burial diagenesis of argillaceous sediment, south Texas Gulf of Mexico sedimentary basin a reexamination. Geol. Soc. Am. Bull. 109, 2-15. 

No perfectly homogeneous isotropic sedimentary basin exists in nature, though certain parts of existing basins may be considered homogeneous, favouring burial-driven vertical upward flow of groundwater. 

In addition to the grovmdwater pressure distribution, the burial-induced flow of groundwater is associated with several physical and chemical characteristics of the sedimentary basin. These include the distribution of temperature, salinity and chemical composition of the groundwater, and the distribution of diagenetic minerals in the basin. 

Bjdrlykke, K. and H0egh, K. 1997. Effects of burial diagenesis on stresses, compaction and fluid flow in sedimentary basins. Mar. Pet. Geol., in press. 

The rate of the smectite - illite reaction is thus directly proportional to K"" and H+, but is retarded by and by dissolved silica and Na". In deepening sedimentary basins, the extent of the reaction at any depth also depends on the local thermal gradient (temperature) and the sediment burial rate (reaction time). Because smectites of small particle size are the least stable, they alter to illite at lower temperatures than do coarser-grained smectites (Fig. 9.5). 

The origin of saline formation water in sedimentary basins has been problematical since it was first recognized that basinal fluids typically contain dissolved solids in concentrations considerably in excess of seawater. Vast differences in major-ion ratios quickly dispelled early assiunptions that basinal fluids were connate and represented buried seawater (Chave, 1960). Since then, different mechanisms have been advocated to account for the composition of subsurface water, and indeed, different mechanisms probably operate in basins with different lithologies and different burial histories. In some cases saline formation water may evolve in near isochemical rock—water systems during burial, as increasing temperature and pressure induce reactions which transfer components from the solid to the dissolved state. At the other end of the spectrum, fluid bearing no resemblance to the interstitial burial water may be imported from another part of the basin, or even from outside the basin, for example, by meteoric recharge, and modified by rock—water interaction. 

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