Overview Onboard Geophysicist

By: Harris Tri PratamaOverview Onboard GeophysicistGeophysicists must be read the PEP for the guidance onboard. Geodetic parameter & Coordinate locationLine intervalSurvey equipment2D High Res Seismic Parameter (Only geophysical site survey)Data deliverable

Mobilization Geophysicists must be prepare all templates that needed onboard.Preliminary reportSound Velocity Profile Calibration ReportsSoil Sampling Log

Sound velocity is important for MBES data to get precise water depth.SVP is use for check the water depth either MBES and SBES. (depends on water depth)Thermocline zone is depth at which the rate of decrease of temperature with increase of depth is the largest.

SVP

Thermocline zoneSoil Sampling Log

Geophysicists must check and calibration the geophysical equipment (Sound Velocity Profiler, Side Scan Sonar and Pinger).

SSS Rub test SSS Wet test

Pinger wet testGeophysicists must ensure the connection is connect with other PC (ProMax, Processor, Surveyor, Analogue, Digital and Back-up hard disk).Geophysicists must involve and ensure the parameter of 2D High Res Digital Seismic (Near Offset, Gun Depth, etc.)

2D High Res Digital Seismic

Geophysicists must playback all data after recording in software processing (CODA, Sonarwiz, Discover), for 2D High Res, the data can be playback after process by ProMax Processor.All geo hazards that it found when playback the data must be inform into QC Geophysics Log data.

QC Geophysical Data Onboard

QC Geophysical Data OnboardFor Single beam Echosounder (SBES) and Multibeam Ecshounder (MBES), geophysicists must ensure the water depth has the same value between them, if not the same please ensure the draught check value in SBES.

d = depth from water surface v = average speed of sound in watert = measured travel time dr= Draught d = ((V*t)/2) + dr

MBES Bathymetry*The water depth value is not equal, due to the input value of draught check is incorrectSBES Bathymetry

For SSS, geophysicists must ensure the data hasnt a gap because of position jumping or not injected and cover range.

QC Geophysical Data Onboard

Position InjectedPosition Not InjectedFor Pinger, geophysicists must ensure the layer is continue with visually, except in bad weather condition and position is injected.

QC Geophysical Data Onboard

Bad data record

Good data recordGeophysicists must check the area that surveyed is in corrected coordinate with overlay one of the mosaic SSS data and survey grid.

QC Geophysical Data Onboard

Geophysicists must check the distance between SSS and Pinger is right with overlay their trackplot.

QC Geophysical Data OnboardSeabed tagTagging featuresGenerate taggingMosaic

Geophysical Processing (SSS)Tagging R1Tagging geo-hazard (Shallow Anomaly, Shallow Channel and Fault)Tagging Seabed, It must injected the cornav (CNV) before taggingGenerate the taggingGeophysical Processing (Pinger)Seabed features mapGeophysical Interpretation (SSS)

Isopach mapShallow Channel and Anomaly development map

Geophysical Interpretation (Pinger)

Preliminary report based on all geophysical data in 500-m radius from the proposed location (Geophysical Site Survey) and Based on the proposed pipeline route (pipeline route survey).

Geophysical Reporting Onboard