OPR-M367-RA-18Cascadia MarginOffshore Southern OregonNOAA Ship RAINIERH132065Saint George ReefCaliforniaOregonUnited States800002018Benjamin Evans, CDR/NOAANavigable Area2018-06-272018-08-142018-08-15Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUTC -7Pacific Hydrographic BranchThe purpose of this survey is to provide contemporary surveys to update National Ocean Service (NOS) nautical charts. All separates are filed with the hydrographic data. Any revisions to the Descriptive Report (DR) generated during office processing are shown in bold red italic text. The processing branch maintains the DR as a field unit product, therefore, all information and recommendations within the body of the DR are considered preliminary unless otherwise noted. The final disposition of surveyed features is represented in the OCS nautical chart update products. All pertinent records for this survey, including the DR, are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via http://www.ncei.noaa.gov/.NOAAThe project instructions reference sheet H13117 which was subsequently split into H13117 and H13206. Please see the supplemental correspondence for more information on the split. The survey area for H13206 is referred to as Saint George Reef (sheet 5). The area encompasses approximately 238 square nautical miles. The area is roughly rectangular extending from 25 nm west of Crescent City, CA to to 17 nm west of Rogue River, OR, as shown in Figure 1.42.4094444444124.9241.7655555556124.834166667Cyan tint shows the coverage area of H13206 offshore CA-OR border.file:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_Survey_Area.pngData were acquired within survey limits as required in the Project Instructions and HSSD unless otherwise noted in this report.The primary purpose of this survey is to provide bathymetry, backscatter, and water column data to the United States Geological Society (USGS) Hazard Mission Area objectives. The survey also supports the Expanding Pacific Research and Exploration of Submerged Systems (EXPRESS) campaign. Additionally, the survey supports NOAA's Integrated Ocean and Coastal Mapping project and updates NOAA's nautical charting products. The bathymetric data will be used as a pre-event baseline to be analyzed after large earthquakes. The water column data will be used to continue mapping sea floor seep distribution.The entire survey is adequate to supersede previous data.Pydro QC Tools 2 Grid QA was used to analyze H13206 multibeam echosounder (MBES) data density. The submitted H13206 variable-resolution (VR) surface met HSSD density requirements.Pydro derived histogram plot showing HSSD density compliance of H13206 finalized variable-resolution MBES data.file:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_MB_VR_MLLW_Final.QAv5.density.pngAll waters in survey areaComplete coverage MBES data, backscatter data, and water column data. Refer to HSSD Section 5.2.2.3.Survey coverage was in accordance with the requirements listed above and in the HSSD.H13206 MBES Coverage with Sheet Limitfile:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_MBES_Coverage.pngS2210239.800000000239.8000000000000238.472018-08-152018-08-16Refer to the Data Acquisition and Processing Report (DAPR) for a complete description of data acquisition and processing systems, survey vessels, quality control procedures and data processing methods. Additional information to supplement sounding and survey data, and any deviations from the DAPR are discussed in the following sections.S22170.44.7NOAA Ship Rainier (S221)file:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_Vessel_S221.jpgAll data for H13206 were acquired by NOAA Ship RAINIER (S221). The vessel acquired depth soundings, backscatter imagery and sound speed profiles.Kongsberg MaritimeEM 710MBESTeledyne RESONSVP 70Sound Speed SystemSippicanXBT Deep BlueTemperature sensorApplanixPOS MV 320 v5Positioning and Attitude SystemThe priority for this project was to maximize overall MBES coverage during the short duration of acquisition. Given this priority and the deep, offshore nature of the survey area, crosslines were not acquired. See Appendix 2, Supplemental Correspondence. A waiver from HSD Operations Branch has been requested.00.173ERS via VDATUMS221N/AN/A0.05Expendable Bathythermographs (XBT) were used in lieu of a CTD or MVP due to the survey depth. The measured XBT sound speed uncertainty used for H13206 was 4 m/s. Total Propagated Uncertainty (TPU) values for survey H13206 were derived from a combination of fixed values for equipment and vessel characteristics, as well as from field assigned values for sound speed uncertainties. Tidal zoning uncertainty of 0.173 meters was provided in the Project Instructions as part of VDatum. See the 2018 DAPR for further information. In addition to the usual a priori estimates of uncertainty, some real-time and post-processing uncertainty sources were also incorporated into the depth estimates of this survey. Real-time uncertainties from Kongsberg MBES sonars were recorded and applied in post-processing. Applanix TrueHeave (POS) files, which record estimates of heave uncertainty, were applied during post-processing. Finally, the post processed uncertainties associated with vessel roll, pitch, yaw, and position were applied in Caris HIPS using SBET and RMS files generated using POSPac MMS software. Uncertainty values of the submitted finalized grid was calculated in Caris using "Greater of the Two" of uncertainty and standard deviation (scaled to 95%). Grid QA v5 within Pydro QC Tools 2 was used to analyze H13206 TVU compliance, a histogram plot of the results is shown below.Pydro derived plot showing TVU compliance of H13206 finalized multi-resolution MBES data.file:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_MB_VR_MLLW_Final.QAv5.tvu_qc.pngNo junctions were performed on sheet H13206.Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR.Sonar Ping ModeSurvey H13206 was acquired to produce bathymetric data and high quality backscatter data. In order to acquire high quality backscatter, minimal changes to the sonar's operating mode were required. Instead of operating sonar ping mode automatically, it was manually switched between "shallow", "medium", "deep", "very deep", and "extra deep" where appropriate. The hydrographer monitored the effects of these manual changes out in the field and found no issues with the resulting data.None ExistThere were no other factors that affected corrections to soundings.At least once every four hours.Additional casts were taken when significant changes to surface sound speed were observed or when operating in a new area. Sound speed profiles were acquired using Sippican Deep Blue XBT Profilers. All casts were concatenated into a master file and applied to MBES data in Caris HIPS using the nearest in distance within time 4 hours profile selection method. The first cast was taken outside the sheet limits to give the sonar system an SVP profile before starting the first line of MBES acquisition, as shown in Figure 6.H13206 Cast Locationsfile:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_Cast_Locations.pngAll equipment and survey methods were used as detailed in the DAPR.Detect FliersPydro QC Tools 2 Detect Fliers was used to find fliers in a finalized VR surface. The following are the settings used for Detect Fliers: (1) Force flier heights left blank (2) Checks - #1 and #6 unchecked, # 2 #3 #4 and #5 checked (3) Filters - Distance <= 1.0 nodes, Delta Z <= 0.01 meters, #1 and #2 unchecked Obvious noise was rejected by the hydrographer in Caris subset editor. After data cleaning, Detect Fliers listed five potential fliers. All potential fliers are outside the sheet limit. All potential fliers were investigated in subset editor and were found to be natural slopes comprising the sea floor. The results of the Detect Fliers tool are included as a .000 file in the Pydro QC section of this report. Potential fliers shown in Figure 7.Results for Detect Fliersfile:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_Detect_Fliers.pngAll data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.All equipment and survey methods were used as detailed in the DAPR.CarisHIPS/SIPS10.3.3FledermausFledermaus Geocoder Toolbox (FMGT)7.8.1NOAA Profile V_5_7H13206_MB_VR_MLLW_FinalCARIS VR Surface (CUBE)Variable Resolution1394.2523.5NOAA_VRComplete MBESH13206_MB_VR_MLLWCARIS VR Surface (CUBE)Variable Resolution1394.2523.5NOAA_VRComplete MBESSubmitted surfaces were generated using the recommended parameters for "Ranges" style variable resolution bathymetric grids as specified in HSSD 2018. No soundings were designated in this survey and no Dangers to Navigation (DTONs) were detected throughout the survey area.Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying HVCR.Mean Lower Low WaterERS via VDATUMshapefile_xyNAD83-MLLW_geoid12b.csarNorth American Datum 1983Projected UTM 10Precise Positioning-Real Time Extended (PP-RTX) processing methods were used in Applanix POSPac MMS 8.1 software to produce Smooth Best Estimates of Trajectory (SBETs) for post-processing horizontal correction.A comparison was made between H13206 survey data and Electronic Navigation Chart (ENC) US3OR03M. This was accomplished by creating CUBE surfaces and contours in Caris and comparing the surveyed contours with the charted depth curves on chart US3OR03M. The chart used is the most recent edition.US3OR03M196948212018-07-192018-07-19falseA comparison with H13206 surveyed contours and ENC US3OR03M revealed the following: All surveyed contours generally agree with the ENC charted depth curves except in southern portion of the survey. Minor revision is required for the H13206 survey area, as shown in Figure 8.ENC US3OR03M overlaid with H13206 surveyed contoursfile:///M:/OPRM367RA18/Surveys/H13206/Office_Processing/Reports_office/Components/SupportFiles/H13206_Chart_Comparison.pngNo Maritime Boundary Points were assigned for this survey.No charted features exist for this survey.No uncharted features exist for this survey.No shoals or potentially hazardous features exist for this survey.No channels exist for this survey. There are no designated anchorages, precautionary areas, safety fairways, traffic separation schemes, pilot boarding areas, or channel and range lines within the survey limits.No bottom samples were required for this survey.Shoreline was not assigned in the Hydrographic Survey Project Instructions or Statement of Work.No Aids to navigation (ATONs) exist for this survey.No overhead features exist for this survey.No submarine features exist for this survey.No platforms exist for this survey.No ferry routes or terminals exist for this survey.No abnormal seafloor and/or environmental conditions exist for this survey.No present or planned construction or dredging exist within the survey limits.No new surveys or further investigations are recommended for this area.No new insets are recommended for this area.As Chief of Party, field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports.All field sheets, this Descriptive Report, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch.The survey data meets or exceeds requirements as set forth in the NOS Hydrographic Surveys Specifications and Deliverables, Field Procedures Manual, Letter Instructions, and all HSD Technical Directives. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required with the exception of deficiencies noted in the Descriptive Report.Benjamin K. Evans, CDR/NOAAChief of Party2018-12-19Andrew R. Clos, LT/NOAAField Operations Officer2018-12-19James B. JacobsonChief Survey Technician2018-12-19Christopher K. DunnSheet Manager2018-12-19