Lyell Collection

Geological Society, London, Special Publications

Lyell Centre  |   Lyell Collection  |   Subscriptions   |   Geological Society  |   Email alerts  |   Online bookshop  |   Help


Keywords:
Author:
Advanced search>>
This Article
Right arrow Full Text (PDF)
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Strong, G. E.
Right arrow Articles by Milodowski, A. E.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation
Geological Society, London, Special Publications; 1987; v. 36; p. 325-337;
DOI: 10.1144/GSL.SP.1987.036.01.23
© 1987 Geological Society of London

Regional Studies and Burial Diagenesis

Aspects of the diagenesis of the Sherwood Sandstones of the Wessex Basin and their influence on reservoir characteristics

G. E. Strong & A. E. Milodowski

British Geological Survey, Keyworth, Nottingham NG12 5GG, UK

The Sherwood Sandstone Group sandstones of the Wessex Basin are important potential reservoirs for both hydrocarbons and geothermal brines. Analyses of conglomerate, sandstone and siltstone samples from outcrop and deep boreholes indicate a complex diagenetic history that has had important positive and negative effects on the reservoir properties. Over most of the basin, early diagenesis (eodiagenesis) is dominated by calcrete development but, towards the basin centre, non-ferroan dolomite associated with early evaporitic sulphate cements that appear to have been deposited in an inland sabkha or playa environment are important. Later diagenesis (mesodiagenesis) is characterized by selective framework grain dissolution of feldspars, and anhydrite cementation and subsequent dissolution—processes that have locally yielded significant secondary porosity. However, in some cases this secondary porosity has been destroyed by the precipitation of late manganiferous ferroan calcite and ferroan dolomite. Quartz cements are locally important. Rocks near the present-day outcrop have been affected by weathering processes (telodiagenesis) that have resulted in decalcification, and the precipitation of kaolinite, illite and iron hydroxides. The key factors determining the permeability of the sandstones are the original grain size and degree of sorting, the precipitation and subsequent removal of anhydrite, and the extent of early and late carbonate cementation, framework grain dissolution and overgrowth.





This article has been cited by other articles:


Home page
Geological Society, London, Special PublicationsHome page
D. J. Evans and S. Holloway
A review of onshore UK salt deposits and their potential for underground gas storage
Geological Society, London, Special Publications, 2009; 313: 39 - 80.
[Abstract] [Full Text] [PDF]


Home page
Geological Society, London, Special PublicationsHome page
J. Parnell
Diagenesis and fluid flow in response to uplift and exhumation
Geological Society, London, Special Publications, 2002; 196: 433 - 446.
[Abstract] [PDF]


Home page
Geological Society, London, Special PublicationsHome page
R. Metcalfe, C.A. Rochelle, D. Savage, and J.W. Higgo
Fluid-rock interactions during continental red bed diagenesis: implications for theoretical models of mineralization in sedimentary basins
Geological Society, London, Special Publications, 1994; 78: 301 - 324.
[Abstract] [PDF]