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Full QC Service
This comprises
provision of staff and systems for comprehensive evaluation of positioning
and/or seismic data as it is acquired or during/ following processing. For QC of
positioning data the company offers Quest Geo-Solutions’ GeoMetis Suite of
processing, reporting and QC products, enhanced with additional toolbox modules
where appropriate. For seismic data QC and evaluation, WTW is able to supply 2D
or 3D ProMAX systems running on Sun or PC platforms.
All WTW’s positioning QC Consultants and Analysts have
extensive experience in the processing of positioning data, as well as a good
knowledge of acquisition parameters and techniques. This experience is
invaluable in situations where positioning data is processed in the field, since
the experience of many QC personnel is limited to the acquisition elements of
positioning and surveying. Quest’s PXCheck format compliance checking software
ensures that final SPS, P1 or raw P2 data for archiving complies in all respects
with UKOOA standards.
WTW is able to supply seismic
consultants with backgrounds appropriate to the required tasks. These include
generalists, who are able to take on most QC-related tasks, and specialists (eg
experienced ProMAX operators) for processing comparisons, Geophysicists with
ProMAX experience for more advanced technical evaluations, etc.
Positioning QC may be carried out by spot-checking or by full
reprocessing of some/ all of the data gathered followed by comparison of
contractor-generated and WTW-generated P1 files. Independent checks on recent
surveys have highlighted incorrect offsets, badly set up filters, poor network
observation selection, bad compasses and geometry problems. Checks on OBC data
have shown receivers positioned using incorrect source lines, receivers pulled
out of position following deployment, poor contractor picking. Use of PXCheck
has highlighted numerous instances of cosmetic and data errors in supposedly
completed/checked P2 and P1 data sets.
rGPS range showing bias of data
reverse-engineered from Contractor P1(magenta)
compared with WTW result (red) and raw/ filtered data (green/blue)
WTW is able to QC effectively the whole range of
positioning data, from land survey data, through TZ and OBC to 2D/ 3D/ 4D towed
streamer operations. The company is very experienced in QCing QMarine
operations, a task for which the GeoMetis suite is ideally suited. WTW is also
experienced in the QC of downstream and engineering activities such as rig
moves, pipeline inspection, site surveys, etc.
QC of suspected spurious cable
movement
WTW and Associates is a member of the
IAGC
and is registered with
FPAL.
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Welcome to WTW and
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