The Villeperdue oil field is located in the Paris basin less than 100 km east of Paris. The first well was drilled in 1959 and tested some oil, but it was not until 1982 that exploration was resumed and the field proved commercial.
The trap is not obvious from seismic data because of velocity variations in the Tertiary and in the Cretaceous chalk. It is a combination of stratigraphic, structural, and diagenetic features. The structure is a western-plunging nose, the eastward updip closure being controlled mainly by variation of permeability and possibly influenced by gentle faults and pressure barriers. The Villeperdue field has a producing surface area of about 65 km2 and a 60-m oil column.
The reservoir is an oolitic limestone of Middle Jurassic (lower Callovian) age. Its average thickness is about 30 m and its approximate depth is 1850 m (1650 m subsea). Two main units, linked to specific oolitic microfacies, can be identified. Detection of porosity over the field, and consequently delineation, are therefore dependent on detailed facies and sedimentological studies.
The generation of oil from Liassic source rocks started during the Cretaceous, and the migration upward into the lower Callovian carbonate was made possible by Tertiary faulting.
The current production of 12,000 BOPD comes from 100 wells and is enhanced by water injection. Horizontal drilling has given positive results and will be used more in future programs.
The play concept has been successfully applied on a regional basis and has resulted in several other discoveries, although minor in size.
Figures & Tables
Giant Oil and Gas Fields of the Decade 1978-1988
The success of Memoir 14 and the worldwide interest shown for data on giant fields prompted AAPG to schedule a symposium on giant fields at the end of each subsequent decade. The 1968-78 symposium was held in Houston, Texas, April 1-4, 1979, and the papers were published in AAPG Memoir 30, December 1980.
The Stavanger Conference "Giant Oil and Gas Fields of the Decade: 1978-1988" was held in Stavanger, Norway, September 9-12, 1990, and is a continuation of the Giants of the Decade series.
Scientific studies and projections of future world energy demand indicate that although alternative-energy fuel sources must be actively pursued and developed, there also must be adequate petroleum supplies to bridge the gap. For the international petroleum industry, the years covered by this conference, 1978-88, were complex. They were years of boom and bust. The world's energy consciousness was boosted sharply by the effects of the 1979 Iranian revolution and the resulting embargo, which sent world oil prices to record heights. Global petroleum exploration soon surged, leading to the industry's all-time drilling high in 1981. Then came the oil price collapse in 1985, and the following years were characterized by falling oil prices and drastic budget cuts for exploration and development.
Although exploration dropped sharply during the latter part of the decade, there was a steady flow of giant oil and gas field discoveries. Using the giant field designation criteria of 500 million bbl of oil recoverable for fields in Asiatic Russia, North Africa, and the Middle East,