AS SEEN IN
APRIL 2014
Protecting offshore operations
from ice hazards
New ice management system helps operators keep Arctic offshore
drilling and production facilities safe.
Terry Kennedy, ION Geophysical
E
very year, blue-white glaciers inching down the western slopes of the 100,000-year-old Greenland ice
sheet plunge icebergs into Baffin Bay. Slowly melting
fragments drift south in the Labrador current along the
eastern coast of Canada, heading eventually toward
strategic offshore oil facilities on the Grand Banks of
Newfoundland. Icebergs and jagged rafts of sea ice
threaten the safety of drilling rigs, platforms, oil tankers,
and FPSO vessels.
“Iceberg Alley,” as the area is known, has seen more
than 500 collisions between icebergs and ships. The HMS
Titanic went down a few hundred miles from the Hibernia oil field, site of the world’s largest offshore platform.
Hibernia’s gravity-based structure is reportedly designed
to withstand a collision with a 1-million-ton iceberg, but
no one actually wants to test its durability. Over the past
few decades, therefore, operators and service companies
working off the coasts of Labrador and Newfoundland
have devised clever ice management strategies.
Ice management teams prevent icebergs of all sizes
from colliding with rigs and other costly facilities. To
locate, track, and predict potential ice hazards in a
timely manner, ice specialists require reams of detailed
ice, weather, and ocean information. Commercial vendors have developed electronic ice navigation and data
management systems. But many of these tools suffer
from shortcomings, especially when faced with chaotic,
unpredictable ice conditions. ION’s new Narwhal technology represents a step-change in integrated ice data
access, visualization, and decision-making efficiency.
As more nations such as Russia open ice-infested waters
to exploration and drilling, more operators will need to
implement effective ice management operations.
seismic acquisition find it much easier to dodge the ice.
Fixed or relatively fixed facilities such as drilling rigs
and FPSO vessels are more complex and costly to move.
Every minute the drillbit stops turning or oil stops flowing, asset owners are losing money. This is why every offshore operation in ice-prone waters has a formal ice
management plan specifying procedures for almost
every conceivable situation. Judgment and sound decisions, of course, are critical pieces of the puzzle.
Ice management vessels (IMVs) are tasked with keeping ice out of the operational area. During a drilling
operation off the coast of Greenland, a 1,500-m (4,920ft) iceberg floated south past a rig. Two days later, a
storm shattered the berg into 150 pieces and drove
them back north. A handful of IMVs had to pick their
way through potentially lethal debris, lassoing fragments
with ropes or special nets and towing them away or shoving them off course with their propellers (a technique
called prop washing) to ensure the safety of the rig.
Effective ice management operations
Whenever pack ice or an iceberg threatens an offshore
operation, ice management teams can either move the
operation or move the ice. Mobile operations such as
COPYRIGHT
©
The Hibernia platform can withstand a direct collision with a
1-million-ton iceberg. (Image courtesy of Hibernia)
HART ENERGY | 1616 S. VOSS, STE. 1000, HOUSTON, TX 77057 USA | +1 713 260 6400 | FAX +1 713 840 8585
HARSH ENVIRONMENT
& ARCTIC ADVANCES
Sometimes nature gets out of control, and some part
of the operation must be removed from harm’s way.
During a heavy ice season off the Grand Banks one
year, IMVs defended an FPSO vessel while the semisubmersible rig was towed away for a couple of days until
the threat passed. At a cost of perhaps US $1 million
per day, operators are loath to take this type of action.
On another occasion, an iceberg had grounded in
shallow water 16 km (10 miles) away. In the middle of
the night, after sitting harmlessly for days, the berg
started to drift toward a tanker offloading oil. To comply
with HSE requirements outlined in the ice management
plan, the tanker was disconnected and moved away
while IMVs deflected the danger. At 5:30 a.m., the
partner who owned that particular shipment called
to understand exactly what had happened. He had
to explain to management why they were paying the
overnight carrying charges on 860 MMbbl of oil.
Lost time always impacts the bottom line. Effective ice
management seeks to mitigate ice risks while reducing
downtime to the absolute minimum. An experienced ice
observer, rapid access to diverse ice data, and efficient ice
management technology are essential to success.
difficult to visualize, overlay, and correlate one piece
with another. Some data such as vessel positioning,
weather, currents, and sea temperature could not be
accessed. Ice analysis was therefore slow and inefficient.
ION’s own ice observers, working extensive seismic
surveys in Arctic waters since 2006, became frustrated
with existing software’s inability to automate, integrate,
or visualize critical ice data. As a result, ION’s Concept
Systems group developed Narwhal for Ice Management,
a patented and fully integrated system that automatically
downloads, updates, timestamps, and geo-references
every ice product available. With unlimited layers, ice
specialists correlate, analyze, and visualize all of the ice,
weather, radar, and ocean data required to make
informed decisions in rapidly changing conditions.
One of the most valuable features is the “trafficability”
or routing capability. Every offshore vessel has an ice rating, indicating the concentrations of sea ice it can safely
navigate. With vessel ratings and maps of current ice conditions, the software graphically displays – and continually
updates – go and no-go zones. This allows ice management teams to determine appropriate routes for tankers
and supply boats to traverse icy waters from producing
fields to the mainland, ensuring safety and minimizing
fuel costs.
The calendar feature in Narwhal can animate ice
movements and other changes over any selected period
of time. It can run backward or forward in time, even
projecting ice trajectories a day or two into the future.
At the end of an operational season, ice analysts can
visually review ice incursions and towing incidents using
the calendar feature to help meet reporting requirements, study ice behaviors, and fine-tune parameters
for the next season.
Additional capabilities include multivessel data sharing and visualization, automated alerts for approaching
ice, and the ability to track birds and marine mammals
in ecologically sensitive areas.
Efficient ice management technology
Growing Arctic activity
Anticipating ice threats as early as possible depends on
live radar, satellite images, aerial photographs, weather
reports, bathymetry, ice and navigation charts, and
other information. In the past, ice analysts printed fax
reports, plotted hard copy maps and images, and sifted
through piles of data scattered about the bridge.
Early ice navigation software combined electronic ice
charts, satellite images, and radar on a single computer.
However, data files had to be downloaded from various
sources via FTP and manually checked for quality. Some
data was not geo-referenced or timestamped, making it
Declining reserves from mature fields, growing demand
for oil, and retreating sea ice have sparked new activities,
with six of the eight countries with Arctic territories
granting energy companies offshore exploration licenses
despite the enormous challenges. To optimize ice
defense strategies and ensure the safety of personnel,
facilities, and the environment, operators must make
timely, well-informed decisions. Reliable ice management technology will be critical to ensuring the industry’s ability to safely explore, develop, and produce in
this delicate but harsh environment.
Narwhal can show go and no-go zones based on a particular
vessel’s ice classification. (Image courtesy of ION Geophysical)
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HART ENERGY | 1616 S. VOSS, STE. 1000, HOUSTON, TX 77057 USA | +1 713 260 6400 | FAX +1 713 840 8585