American Oil and Gas Reporter - April 2016 - 40

SpecialReport: GOM Field Development
The results demonstrate how the combination of these borehole data types was
able to identify cycles of high-energy
mass transport deposits followed by relatively lower-energy phases of sand deposition. The impact of geological deformation affects the geological interpretation,
and the connectivity and types of fluids
present in the reservoir. Pressure and
fluid analysis from formation testing data
confirmed nonlinear relationships at different depths, which then were analyzed
for implications to the reservoir.
Delta House achieved first oil in April
2015, only three years after the first of
three anchor fields was discovered. After
drilling discoveries at Son of Bluto 2 in
Mississippi Canyon 431 and Marmalard
12 miles to the north in Mississippi
Canyon 300, LLOG and its partners initiated a process to develop a regional
host facility to handle these and other
potential discoveries.
Comprehensive Model
With the speed required to satisfy a
quick turnaround to develop the facility,
the subsurface team recognized the need
to maximize all the data acquired within
the Son of Bluto 2 and Marmalard wells
to make decisions about the overall value

FIGURE 2
Synthetic VSP Overlain with Actual Upgoing VSP Wave Field

of the reservoirs to be developed. Surface
seismic was a critical part of the equation,
as was a full set of wireline data.
From a development perspective, an
accelerated time frame has a tremendous
impact on project economics. To ensure
that accelerated development was appropriate, the subsurface team worked with
all available data for integrating into a
comprehensive subsurface model that

FIGURE 1
Seismic Profile with 3-D Structure Map Showing
Marmalard Discovery and Follow-Up Wells

Source: Image courtesy of TGS

40 THE AMERICAN OIL & GAS REPORTER

also incorporated subsequent development.
Reservoir, geologic and geophysical logging were performed and integrated into
the model to establish a base line for development. This integration was used for
both project development and follow-up
drilling.
In the case of Marmalard, the integrated
reservoir model supported drilling a follow-up well more than 3.5 miles from
the discovery well because it indicated
connectivity between the wells. Figure 1
displays a seismic profile with a threestructure map, showing the overall structure of the primary zone at Marmalard,
and the locations of the discovery and
follow-up wells.
The majority of the reservoir features
targeted are late and middle Miocene in
age. The interpreted depositional model
is that the region was dominated by largescale proximal turbidite fan features that
were laid down on a relatively flat seafloor.
Later, clay drape particles were deposited
in intervals between large channel and
fan deposits. Also, later mass transport
complexes and channels scoured the original fan sequences. These elements are
interpreted through detailed analysis and
integration of wireline logs synthesized
to create an overall geologic model.
Borehole Seismic
A vertical seismic profile was planned
for the second well to establish an accurate
time/depth relationship, and to provide a
seismic character tie with the 3-D surface
data at the well location. Appropriately,
prejob VSP ray trace modeling was performed, based on an interpretation of the

American Oil and Gas Reporter - April 2016

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