LECTURE no.

RESEARCH VESSEL

Research Vessel What Are They?

A research vessel (RV or R/V) is a ship designed and equipped to carry out research at
sea. Research vessels carry out a number of roles. Some of these roles can be combined into a
single vessel, others require a dedicated vessel. Due to the demanding nature of the work,
research vessels are often constructed around an icebreaker hull, allowing them to operate in
polar waters.
Research vessels falls roughly into six size categories, regarding they navigation zone:
Global Class ships are the high endurance vessels. They are large general-purpose,
multidisciplinary oceanographic research ships capable of worldwide cruising and able to support both
over-the-side and laboratory work in high sea states. The ships can accommodate large scientific
parties
Ocean Class ships are the increased endurance, technological capability and number of science
berths then ordinary ships.
Intermediate Class ships are medium endurance, general-purpose research vessels.
Regional Class ships work in and near the continental margins and coastal zone. They are
general-purpose ships, designed to support integrated, interdisciplinary coastal oceanography in the
broadest sense from shallow coastal bays and estuaries out to deep water beyond the shelf
Regional/Coastal Class ships operate in a mode that is similar to the Regional ships; however,
they are generally smaller in size and tend to have lower operating costs.
Local Class ships fulfill near-shore needs that do not require larger or higher-endurance ships.
They are fully capable of continuous 24-hour operations. Although these ships are designed for small
size and cost effectiveness, they still have the multidisciplinary capabilities required by modern
research.
Regarding they purposes, the research vessel falls into the next general categories:

Hydrographic survey
A hydrographic survey ship is a vessel designed to conduct hydrographic research and
survey. Nautical charts are produced from this information to ensure safe navigation by
military and civilian shipping. Hydrographic survey vessels also conduct seismic surveys of
the seabed and the underlying geology. Apart from producing the charts, this information is
useful for detecting geological features which are likely to bear oil or gas. In practice,
hydrographic survey vessels are often equipped to perform multiple roles.
Oceanographic research
Oceanographic research vessels carry out research on the physical, chemical and
biological characteristics of water, the atmosphere and climate, and to these ends carry
equipment for collecting water samples from a range of depths, including the deep seas, as
well as equipment for the hydrographic sounding of the seabed, along with numerous other
environmental sensors. These vessels often also carry scientific divers and unmanned
underwater vehicles
Fisheries research
A fisheries research vessel (FRV) requires platforms which are capable of towing
different types of fishing nets, collecting plankton or water samples from a range of depths,
and carrying acoustic fish-finding equipment. Fisheries research vessels are often designed
and built along the same lines as a large fishing vessel, but with space given over to
laboratories and equipment storage, as opposed to storage of the catch.

Naval research
Naval research vessels investigate naval concerns, such as submarine and mine detection,
sonar and weapon trialing.
Polar research
Polar research vessels are constructed around an icebreaker hull, allowing them to operate
in polar waters. These boats usually have dual roles, particularly in the Antarctic where they
function also as polar replenishment and supply vessels to the Antarctic research bases.
Oil exploration
Oil exploration is performed in a number of ways, one of the most common being mobile
drilling platforms or ships that are moved from area to area as needed to drill into the seabed
to find out what deposits may or may not lie beneath it.
Technical research ship
Technical research ships were used to gather intelligence by monitoring, recording and
analyzing wireless electronic communications of nations in various parts of the world. the true
mission was more or less an open secret and the ships were commonly referred to as "spy
ships".
Weather ship
A weather ship was a ship stationed in the ocean as a platform for surface and upper air
meteorological observations for use in weather forecasting. They were primarily located in the
north Atlantic and north Pacific oceans, reporting via radio. In addition to their weather
reporting function, these vessels aided in search and rescue operations, supported transatlantic
flights, acted as research platforms for oceanographers, monitored marine pollution, and aided
weather forecasting both by weather forecasters and within computerized atmospheric
models.
RADARS, warning lights, and meteorology
sensors
satellite communication equipment

ship control stations

Captain and Chief Engineers quarters

rescue boats

lab and electronics equipment

A-frame crane and crane

bow crane

anchor chain locker

propeller
storeroom for science gear
bow thruster room
tanks for fuel, water and oils
main and auxiliary machinery room

spaces for the science

staterooms for the crew

Fig.2.1. General Arrangement of a research vessel

Located at the very top of the vessel are the masts, RADARS, warning lights, and
meteorology sensors. The large round dome on top of the bridge contains the satellite
communication equipment. Next is the 04 Level with the bridge containing fore and aft ship
control stations, which give the crew great visibility of operations. The 03 Level contains the
Captain and Chief Engineers quarters along with a small lab and electronics equipment. The
02 Level has a large bow crane and staterooms for the rest of the crew. Also there is a winch
control station near the center of the ship as well as work and rescue boats. The 01 Level
holds the berthing spaces for the science party along with other common spaces on the port
side of the ship such as a small gym, galley, mess/lounge, library, and spa. The after-most
stateroom on this level will be wheelchair accessible. Just aft of this stateroom is a second

winch operator station for controlling the Conductivity, Temperature, and Depth CTD as it
is launched through a side door from the Baltic room below it. The Main Deck is where most
of the research activity will take place on this vessel. There are storerooms, a workshop, a
large main laboratory and then the wet lab and Baltic room. On deck there is a large van for
more science space, cranes, and an A-frame. A mooring and the floats for the anchor line are
on deck waiting to be deployed. On the port side and hidden from view the main deck
includes more labs and storage spaces. Below the main deck are the anchor chain locker,
storerooms, food freezers, and the electricians workshop. Next is the winch room for the
CTD and Hydro winches, another storeroom for science gear, the aft winch room, and the
thruster engines. Below that is the bow thruster room, the main and auxiliary machinery
rooms and most of the tanks for fuel, water and oils.

Fig. 2.2. Baltic Room and the CTD

Source: http://iceberg.dri.edu/palmer.php
IMAGES

Fig. 2.3. Research ship OGS Explora

Source: Google images

Fig.2.4. Research ship OGS Explora General Arangement

Source: Google images
VIDEO
http://science360.gov/obj/video/995685be-0e94-440b-898f-11eb41861112/next-generationarctic-research-vessel-track-voyage-discovery
http://www.youtube.com/watch?v=tQxQfQU_hsk
http://www.youtube.com/watch?v=NaVeyySqkz0

SEISMIC SURVEY VESSEL

Why Are Seismic Surveys Needed?

Oil and gas exploration takes place all over the Earths surface. It can be generally
considered as falling into the two main categories:
onshore or land exploration;
offshore or marine exploration
Modern offshore oil and natural gas exploration requires the use of seismic surveys.
Seismic surveys are the only feasible technology available to accurately prospect for oil and
natural gas reserves offshore. Seismic surveys have been used for decades to assess the
location and size of potential oil and natural gas deposits, which often lay several miles
beneath the ocean floor. Modern seismic surveys make offshore energy production safer and
more efficient by greatly reducing the drilling of dry holes (where no oil or gas is found).

Seismic surveys provide information on the depth, position and shape of underground
geological formations that may contain oil or gas. End result is a detailed picture of the
structures and rock formations in the survey area. Seismic surveys help companies decide
whether:
the available information is sufficient to justify drilling an exploratory well
additional surveys are needed to better define the structures before drilling
the features present are not attractive enough to warrant further interest
How Are Seismic Survey Performed?
Generally speaking, the marine seismic survey supposes:
uses sound energy to map geological structures under the seabed;
vessels tow devices that use compressed air to produce pulses of high energy, low
frequency sound waves;
sound waves can penetrate more than 6,000 meters below the sea floor;
travel through the water and into the rock layers beneath the seabed;
bounce back to receivers (hydrophones) that measure strength and return time.

seismic vessel

ocean flooor

sound source
(air gun array)

multiple receiver cables

with hydrophones

geological layers
oil and gas reservoir

Fig.2.5. Seismic survey principle of function

Types of seismic surveys:
two dimensional (2D): uses one sound source and one set of receivers
three dimensional (3D): uses multiple synchronized sound sources and hydrophones
four dimensional (4D): uses multiple synchronized sound sources and hydrophones
with the added dimension of time (i.e.: a 3D survey is conducted multiple times over
the same location at different periods to compare data)
geohazard or well site survey: uses one sound source and one set of receivers towed
over a small area prior to drilling to check for possible hazards
verticial seismic profiles: hydrophones are lowered into a drilled well and sound is
produced at the surface to give a detailed view of the geology near the well bore
The two main types of seismic exploration are seismic refraction and seismic reflection.
Refraction measures the travel time of seismic energy, which travels to the top of a
distinct subsurface density contrast, is refracted along the top of the density contrast and
returns to the surface as a head wave.
Reflection measures the travel time of seismic energy that is reflected from a subsurface
density contrast and is the method to be used here.

Seismic reflection exploration is routinely used worldwide both onshore and offshore to
identify and assess subsurface geological structures, and the potential presence and extent of
any associated oil and gas deposits.
In the offshore environment seismic surveys are conducted by discharging directionally
focused energy pulses in the form of low frequency sound into the water column. These
pulses travel though, and are reflected back from, boundaries exhibiting a difference in
acoustic impedance, defined as the product of seismic wave velocity and density. These
reflections are recorded by receivers (hydrophones), which are deployed in streamers towed
behind the seismic survey vessel. Depths and spatial extent of the strata are then calculated
and mapped, based upon the difference between the time of the energy being generated and
subsequently recorded by the receivers.

Fig.2.6. Acoustic receivers disposal

Source: Google images
In 2D surveys one hydrophone streamer is towed behind the survey vessel, together with
a single source. The reflections from the subsurface are assumed to lie directly below the
streamer/source. This produces a vertical slice or 2D image of the geology below the source.
Typical 2D surveys are designed to cover wide areas and provide a broad understanding of the
subsurface geology. Survey duration varies from several days to months. 2D data can often be
distorted with diffractions and events produced from offline geologic structures, making
accurate interpretations difficult.
In 3D surveys several hydrophone streamers are towed behind the survey vessel, together
with multiple (generally dual) sources. Because seismic waves travel along expanding
spherical wave fronts they have surface area. A truly representative image of the subsurface is
only obtained when the entire wave field is sampled. A 3D seismic survey is more capable of
accurately imaging reflected waves because it utilizes multiple points of observation. Multi
streamer, multi source surveys allow a range of different angles and distances to be sampled
resulting in a volume of seismic data. This allows a more detailed and accurate delineation of
the boundaries and extent of subsurface geological structures. Potential oil and gas reservoirs
can be imaged in three dimensions allowing interpreters to view the data in cross-sections
along 360, in depth slices parallel to the ground surface, and along planes that cut arbitrarily
through the data volume. Information such as faulting and fracturing, bedding plane direction,

the presence of pore fluids, complex geologic structure, and detailed stratigraphy are now
commonly interpreted from 3D seismic data sets.
The air gun is now the most common energy source used in seismic surveys. It works as
follows:
an array of air guns is trailed behind the survey vessel, under the surface of the water
(usually at a depth of anywhere between 5 and 30m, depending on the environmental
characteristics of the marine environment, and also on the target geological structures
being imaged);
Air at high pressure (c. 2000 psi) is supplied continuously to the air guns from air
compressors on the survey vessel. This forces the piston downwards, and the
chambers fill with high-pressure air while the piston remains in the closed position;
when triggered to do so (at prescribed time or distance intervals) the solenoid valve
opens and the piston is forced upwards;
compressed air in the lower chamber flows rapidly out. An air-filled cavity is
produced in the water that expands and then collapses, then expands and collapses
again and continues cyclically. This oscillation creates seismic pressure waves
releasing the energy (sound) into the water column.

Fig.2.7. Air gun device

Air guns produce a short sound (<30 ms), with a relatively rapid rise time (time to reach
maximum amplitude typically <8 ms). Sound levels emitted are typically around 250 dB at 1
m distance for an air gun array. To place seismic signal levels in perspective, low level
background noise in coastal regions is about 60 dB, this corresponds to gentle wave action
and little wind. In adverse weather conditions, the background noise increases to 90 dB.
What Are Seismic Vessels?
Seismic vessels are ships that are solely used for the purpose of seismic survey in the
high seas and oceans. A seismic vessel is used as a survey vessel for the purpose of
pinpointing and locating the best possible area for oil drilling in the middle of the oceans.

Companies engaged in the oil drilling process make use of such vessels so that they find
the best possible subsea areas to drill oil. Another major reason such seismic vessels are so
important is that if oil drillers do not get the best subsea location to drill the oil and gas, then it
could lead to dangerous and threatening consequences for the marine eco-system. The usage
of the seismologic vessels prevents such inadvertent mistakes.
A survey vessel is the one that helps monitor such seismic waves. It is the primary
requirement for any shipping concern engaged in or planning to engage in the process of oil
and gas excavation from the oceanic reservoirs. A seismic vessel is fitted with all
technological gadgets like GPS, computers, nautical charts and any other equipment that
would enhance the process of seismic survey.
Such vessels are built very carefully and only in selected locations across the world. This
is because the entire ship-building process for seismic vessel involves fitting all the necessary
gadgets (mentioned above) without missing even a single one. Seismic vessels are more in
demand in todays time considering the amount of subsea drilling that is being carried out.
They are also known as research vessels because in a completely different way, they do help
research the oceans and seas.
In addition to being vessels that survey underwater seismology, seismic vessels are also
used to study the geology of the oceans and seas. This aspect includes the formation of rocks,
oceanic trenches and many other details that are important and could affect the lives of
humans and marine creatures alike. Thus it can be seen that the main USP of seismic vessels
lies in the fact that it helps not just scientists and researchers find out relevant oil and gas but
also helps them to prevent any other major catastrophe in the form of natural calamities from
occurring.
IMAGES

Fig.2.8. Seismic survey ships

Source: Google images

Fig.2.9. Research ship Vikland

Source: Google images
VIDEO
http://www.youtube.com/watch?v=vrOLWRVGosQ
http://www.youtube.com/watch?v=vOuBcE73Lew