Stratigraphic oil or gas trap produced by porous reef limestones (reservoir rock) covered by impermeable strata. Porosity of limestones depends on post-depositional diagenetic changes. A reef trap may also host lead and zinc mineralization in material deposited from migrating brines. Compare anticlinal trap; fault trap; stratigraphic trap; structural trap; and unconformity trap.
Subjects: Earth Sciences and Geography.