Event Cementation in Sandstones
ROBINSON, ANDREW, BP Exploration, London, England, and JON GLUYAS,* BP Norway, Stavanger, Norway
Precipitation of quartz overgrowths on sand grains is a common cause of porosity reduction in sandstones. The amount of quartz overgrowths ("cement") often increases with depth so that the process of cementation is generally considered to be a direct response to burial and to proceed throughout the burial history of a sandstone. We show that some Mesozoic and Cenozoic sandstones are cemented during events 1-10 m.y. in length, periods one to two orders of magnitude less than their burial histories. Burial alone is unlikely to be the cause of quartz cementation. This new knowledge should markedly change our perception of porosity evolution in sandstones.
AAPG Search and Discovery Article #91007© 1991 AAPG International Conference, London, England, September 29-October 2, 1991 (2009)