WorldOil

Sandstone intrusions: Implications for exploration and production

Sandstone intrusions, or sand injectites, are the natural product of syn- or post-depositional remobilization and injection of sand into surrounding strata due to factors such as overpressure, hydrocarbon migration, diagenesis and seismicity.1-3 The natural processes of sand remobilization and injection and their products in the rock record (sandstone intrusions or sand injectites) should not be confused with any process that may occur or be induced during drilling. Sandstone intrusion occurrence has been discussed over the last two centuries, but they have only recently come to the attention of the petroleum industry due to their importance in the prolific Lower Tertiary play in the North Sea Basin. Their importance in the North Sea, an increasing interest in understanding fluid migration and a possible link between the intrusions and seismicity or even meteorite impacts has sparked a surge in the number of examples reported.