Satellite DGPS systems C-Nav and Veripos are used to carry out receiver and shooting equipment positioning.
DGPS C-NAV2050R receivers are used in the mode of RTG corrections. RTG is a navigation service providing a decimeter accuracy positioning worldwide.
DGPS Veripos LD2-G2 receivers are used in “Ultra” mode. Veripos Ultra is a new generation navigation service providing a decimeter accuracy positioning worldwide. It is based on PPP (Precise Point Positioning) technology, according to which any GPS errors can be both independently corrected or precisely patterned.
DGPS receiver Trimble SPS461 is used for source group center positioning within decametric accuracy, its antennas are located at each source line.
DGPS Trimble SPS351, DSM232, AgGPS132 receivers are used in the base station correction receive mode, providing sub-meter accuracy.
During 3D multi-vessel survey integral navigational system Trigger Fish is used providing on-line control and management of all vessels involved.
Software
NaviPac EIVA, NaviEdit EIVA, TriggerFish , GeoMetis BX and HydroPro v 2.31 programs are used as software for streamer and OBC surveys.
While the bottom cable is being spread, its positioning is done via module sensor receiver. Sonardyne TZ / OBC 12 underwater acoustic positioning system is applied to accurately position the exact location of the bottom cable receiving sensors.
Streamer positioning is done both through compass birds Digicourse 5010, 5011 and the tail buoy equipped with GPS receiver.
Depth Measuring Equipment
We generally apply dual frequency two-beam Simrad EA400 (38/200 kHz) and single-frequency ODOM Hydrotrac (200 kHz) echo sounders. The Simrad EA400 accuracy of depth taking at 200 kHz is equal to 1 cm ± 0,1% , whereas at 38 kHz it is 5 cm ± 0,1%. The Hydrotrac accuracy is 1 cm ± 0,1% . All the vessels are equipped with Furuno FCV 620 (50/200 kHz) dual frequency single-beam echo sounders. Valeport 740 is used as tidal gauge with 0.1% of accuracy. The sound speed is measured by Valeport Mini SVP profilometer. It enables to measure the sound speed in the range of 1375-1900 m / s with an accuracy of 0.02 m / sec.
Sonar survey equipment
High-resolution side-scan sonar EdgeTech 4125-P (400/900 KHZ)is usedto get information of the bottom surface topography and structure.
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