ATP Completes Cheviot 3 -D Seismic Survey

ATP Oil & Gas has completed the seismic survey at its Cheviot property in the North Sea. The program, previously announced by ATP and begun September 12, 2004, was performed by Western Geophysical with its vessel, the Western Regent. This survey encompassed over 150 square kilometers of data acquisition. The orientation and the technical parameters of the 3-D survey were designed to better define the structural and stratigraphic nature of the oil and gas reservoirs. The survey further includes the surrounding previously undeveloped and exploratory locations on the Cheviot property.

The Cheviot property (formerly known as Emerald) originally had estimated in-place oil of 232 million barrels and gas in-place of 59 Bcf. Emerald produced less than 8% of the estimated amount of in-place oil and was developed in the 1990's utilizing 2-D seismic data. Utilization of the 3-D seismic data after it has been processed will enhance for ATP the opportunity to eventually book reserves. ATP has not recorded any estimate of Cheviot oil and gas reserves on its books or in its reserve reports.

Leland E. Tate, Chief Operating Officer, said, "The completion of the 3-D seismic survey is a major step forward in formulating our development plan for this property. During the first half of 2005 we expect to process and evaluate the seismic and based on our findings, move forward with field development plans for the previously developed portion of the Cheviot field. We also intend to examine the possibility of developing other previously drilled but undeveloped locations and exploratory targets confirmed within our lease acreage."