GEOLOGY & GEOPHYSICS
Brownfields offer opportunities
for seismic service sector
OBN technology may be well suited for these applications
At a recent conference primarily for the offshore oil and gas sector, in- dustry CEOs and other key leaders were present and provided their ex- pert insight into where the industry
One very clear message delivered by all
the majors was that the “E” in E&P is dead
– at least for the short- to medium-term, however long that may be. That admission is a
clear signal that the industry recognizes that
a “new normal” is really here.
That means long-term change, perhaps
even radical, structural change, to the industry is underway. For an industry that eschews
quick change, market forces are already carving away at staid conventional approaches and
attitudes about business. Such changes are
potentially huge for the seismic industry; and,
where there is change, there is opportunity.
Seismic is a very small share of the enormous economic engine that comprises the
global oil and gas industry. Interestingly
enough, nearly every decision made in the
oil patch, whether on land or offshore, passes
through the seismic stage gate. It has a key
role in the industry. The right seismic image
can be the difference between a $140-million
dry hole, or a well that produces a billion dollars in oil profits. The quality of that image is
critical in making billion dollar decisions.
And yet, oilfield service companies and
vendors will continue to face a challenging
market in the near term and perhaps beyond. Expectations are that another flat-to-down-year is possible in 2017 as the industry downturn finally bottoms out. It will be
a challenge for service companies of all vari-eties to weather the storm. Seismic companies are similarly challenged, and for certain
types of seismic acquisition methods, and
those companies concentrating their services offerings exclusively at the front- end life-of-field, the challenges may be significant.
Image still key
It is recognized that overall production
will grow in 2016 and beyond. The brownfield is very much alive, perhaps more than
ever, due to the industry’s new normal.
Despite the cuts made to every life-of-field
stage, it is clear that companies will focus
much more on maximizing the productive
capacity of existing brownfields. This will be
truer for offshore field developments than
onshore due to the significant complexities
and associated expense.
The lifting costs and conventional break-even price per barrel associated with an existing producing field offshore, even those
in decline and requiring some form of intervention, are still vastly less expensive than
The math is simple: brownfield breakeven prices/bbl range in the $30/bbl-$50/bbl
spread. For unsanctioned offshore projects,
the average breakeven costs are in the $65/
bbl-$85/bbl range even after the massive
supply chain cost compression experienced
over the past two years of this downturn. Expected average market oil price/bbl in the
$40-$60 range through 2020 makes it clear:
Operators will have to focus on how to best
characterize their existing reservoirs, intervene, and exploit oil production from existing fields as its first priority. Furthermore,
those decisions still have to flow through the
seismic stage gate.
Brownfield seismic methods
Seismic is now ever more critical to maximizing production in the brownfield.
Offshore brownfield exploitation generally
involves operations in remote/difficult-to-ac-cess areas; environmentally sensitive areas;
geologic basins with complex overburden,
structure, and stratigraphy; and most importantly, with field developments characterized
by dense infrastructure. Given these reali-ties, conventional towed streamer “surface”
acquisition is challenged in its ability to provide similar high-quality, reliable, ocean bottom seismic data acquisition.
OBS, and specifically ocean bottom node
(OBN) seismic acquisition is the technology
of choice for the brownfield, and there are
a number of valid reasons why. The most
important reason is found in the type of seis-
mic acquisition required in the brownfield,
generally known as 4D.
Critical in the brownfield, 4D seismic es-tablishes the required time-lapse characterization of the reservoir. However, most mature brownfield reservoirs, developed using
4D seismic, are surveyed only every two,
three, or five years apart. This is obviously
a function of cost and priority. In the past, it
has been mostly about E-seismic. P-seismic
has taken a back seat. But this approach
creates an unnecessarily high risk scenario;
operators can easily miss the opportunity to
effectively manage the reservoir and intervene if needed.
Ultimately, the 4D, P-seismic game is about
creating the highest quality imaging required
to accurately characterize the reservoir, and
then make the critical, best decision about how
to intervene (if at all). Intervention to improve
and further exploit the productive capacity of
the well goes beyond additional profit growth.
Successful intervention effectively delays decommissioning costs, which could run as high
as $60-$70 million in some cases. P-seismic is
an effective cost mitigation strategy as well.
The days of $120/bbl oil and resulting
profitability adequate to cover over the significant opportunity costs created by reservoir management mistakes are gone. Effective and affordable reservoir management
requires a 4D solution that enables multiple,
closely time-separated surveys that measure
how the reservoir is responding to production plans and well interventions.
While towed streamer acquisition is currently the lowest-cost alternative in shooting
virgin seabed and providing reasonable images for greenfield applications, that is not
the case in the brownfield. Towed streamers
often conduct 4D seismic in the brownfield
through wide azimuth (WAZ) surveys. WAZ
requires a huge commitment of time and
expense to conduct, and these surveys have
significant limitations imaging brownfields.
Reservoir image quality is affected by the
towed streamer’s inability to fill the image gaps
created by dense brownfield infrastructure
and other constraints. Nothing can change