Energy has amassed an impressive track record using "Geology 101,"
i.e., paper maps, cross sections, etc., to find new production at
Lake Washington field in Louisiana's Plaquemines Parish.
field, which is located around a shallow piercement salt feature,
was first discovered in the 1930s, and most of the drilling activity
occurred in the 1950s and 1960s. The operating agreement between
operator Exxon and partners Gulf and Shell required unanimous consent
for each project, which proved to hinder development, minimizing
the amount of data collected over the years.
purchased the field in 2001, the deal included no seismic, a few
maps of isolated reservoirs where the most recent operator saw some
opportunity, and computerized historical production data from Exxon.
proceeded in rapid-fire fashion following the Swift acquisition.
In fact, the company has drilled close to 100 wells (averaging 500,000
barrels recoverable per well) with a 79 percent success rate, increasing
reserves from 7.7 million barrels to 43 million barrels -- a huge
payoff using basic, nuts 'n' bolts geology.
mapping at 1,500 feet and did multiple level maps," said Bill Moody,
director of exploitation and development at Swift, "and probably
made 150 old-timey structural cross sections.
a lot of this on the copy machine, shooting logs down using reducing
machines and basically built a framework of seismic lines from cross
sections," he said. "We hooked all the faults up and made fault
plane maps on all the faults, and we overlaid the subsurface structure
maps in base fashion where we could see what the contours did as
we went deeper."
Click images to enlarge
of Swift Energy
computerized production data from Exxon, the team of geologists
and engineers did a lot of material balance work to make sure the
fault blocks mapped were large enough to handle the production that
had come out of them.
then it was back to the drawing board until the geology better fit
the production data.
started drilling wells," Moody said, "the more we drilled, the more
we liked it."
70 productive sands in the Lake Washington area, according to Moody,
and Swift has completed in 33 of these thus far, often encountering
new sands by going deeper than the intended target.
been steering the bit as much as we can along the salt face and
taking it a bit deeper each time, using directional drilling techniques,
which the previous operator hadn't used," Moody said. "This is how
we came into the F Sand, which had not been seen productive in the
field before, and now it's the most productive sand."
exception of a couple of wells, the company's drilling program to
date has concentrated on depths no greater than 6,000 feet. The
Swift team is gearing up to implement the second stage of development,
targeting intermediate depths between 6,000 and 12,000 feet.
To do so,
they'll go high tech, using 3-D seismic data, which doesn't come
cheap in the shallow inland-water environs.
is to acquire 3-D data to get a better image of the salt face going
down and help to better develop the field away from well control.
Moody says it's possible there will even be another round of shallow
development where the 3-D shows additional opportunities.
most of the Lake Washington production is oil, there is a substantial
amount of associated gas being produced. A portion of the gas volumes
is used for gas lift, which is necessary because of the low energy
at the shallow depths being plumbed in the initial development stage
of the property.