Carbonate cementation geochemical zones

Carbonate cements are often among the dominant components of diagenesis and hence are of decisive importance in determining the reservoir quality of sandstone sequences. Despite this, the timing, the geochemical conditions of precipitation and dissolution, as well as the source and fate of these cements are not fully understood. In continental and near-shore sediments, cements commonly precipitate as calcretes and dolocretes in the vadose and phreatic zones, and attain a variety of mineral-ogical, textural and distribution patterns as well as elemental and isotopic compositions. These cements form lenses and layers of densely cemented... 

The timing and conditions of carbonate cementation in the Oseberg Formation in the Oseberg field have been discussed on the basis of petrological, fluid inclusion and geochemical evidence. Samples from structural blocks and from a major fault zone were investigated. 

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