The Itteville Oil Field : An Example of a Stratigraphic Trap in Mid-Jurassic Carbonates of the Paris Basin: ABSTRACT

Abstract

The Itteville Oil Field is located 30 km south of Paris. The top of the reservoir lies at an average depth of 1450 m below sealevel. The field is situated on a large scale monocline dipping gently toward the present center of the Paris Basin. At reservoir level, no anticline closure is seen to explain the oil accumulation. The reservoir is composed of oolitic, peloidal and bioclastic carbonates of Lower Callovian age, regionally known as {open_quotes}Dalle Nacree{close_quotes}. These carbonate sands were deposited by storm-dominated processes during a phase of major sealevel fall which caused the emersion of the main Burgundy Platform. This shoal is completely isolated from the main platform and surrounded by coeval marine shales. Marls corresponding to the Mid-Callovian major flooding event seal the reservoir. The occurrence of these shoals appears to be tectonically controlled. The Itteville Field is situated on a Liassic faulted block seated on the eastern flank of the so-called {open_quotes}Deep Magnetic Anomaly{close_quotes}. Sedimentological studies and high resolution sequential analysis, carried out on cores from 17 wells of the field, help define three main tabular correlable units within the reservoir. Geochemical studies, including cathodo-luminescence and isotope analysis, help define the diagenetic history. Original poroperm propertiesmore » are strongly enhanced by contemporaneous dissolution events related to high frequency sealevel fluctuations.« less