Director s Report: CRTN, Epoch Update & Dynamic Datum. Yehuda Bock

Transcription

1 Director s Report: CRTN, Epoch Update & Dynamic Datum Yehuda Bock California Spatial Reference Center (CSRC) Scripps Orbit and Permanent Array Center (SOPAC) Institute of Geophysics and Planetary Physics (IGPP) Scripps Institution of Oceanography (SIO) University of California San Diego (UCSD) May 4, 2017 IGPP, La Jolla

2 Summary CRTN update Status epoch date for California Dynamic datum Earthquake and Local Tsunami Early Warning System

3 Director: Yehuda Bock Coordinator: Maria Turingan Analysis: Peng Fang System Administrator: Anne Sullivan Programmers: Allen Nance, TBD Archivist & Web Admin: TBD CRTN Engineer: Matt Norenberg Graduate Students: Dara Goldberg, Lauren Coden, Minghua Wang Consultant: John Canas, PLS SOPAC/CSRC Group

4 CSRC Executive Committee Chairperson: Richard C. Maher Vice-Chairperson: Scott P. Martin Secretary: Thomas Dougherty Treasurer: Jim McNeil Member: Bryan Banister Member: Kimberley Holtz Member: Greg Helmer Member: Ken Joyce Non-elected: Past Chairperson: Art Andrew UCSD representative: John Orcutt Director of IGPP: Steve Constable NGS Adviser: Dana Caccamise CSRC Director: Yehuda Bock

5 CRTN Station May 2, :45 PM Started in 2003, 1 Hz RTCM 3.0 data are available from 420 stations from 2 CRTN servers (SC: 207 stations; NC: 213 stations) at SIO with a latency of ~ s. Data directly collected from SCIGN/PBO stations via UCSD s HPWREN, and from servers at UNAVCO/PBO, USGS Pasadena, UC Berkeley, Caltrans, Orange County, and Metropolitan Water District. NAD83(NSRS2007) coordinates transmitted, with station metadata in RTCM 3.0 format

6 CRTN Update Nearly 800 users Increased number of stations to 420 Incorporated 28 USGS/Pasadena stations Completed repairs and maintenance at 24 SCIGN/SOPAC stations, includes OCRTN (Topcon GNSS receivers) Determined location for new Gillespie Field station and rebuilding NSSS in SW corner of County (San Diego County Ray Mathe) Worked with USGS to diagnose Topcon firmware issues

7 CRTN Consortium Members 1. City of Los Angeles, Department of Public Works, Bureau of Engineering, Cesar Bregaudit, Robert Nielsen 2. Riverside County Flood Control and Water Conservation District, Jim McNeil 3. Orange County Public Works, Art Andrew 4. San Diego County, Department of Public Works, Ray Mathe 5. Riverside County Transportation Department, Rick Lantis, Ed Hunt, Tim Rayburn, David McMillan 6. Santa Clara Valley Water District, Kris Puthoff 7. City of Long Beach, Gas and Oil, Kimberley Holtz 8. California Spatial Reference Center, Rich Maher 9. Scripps Institution of Oceanography, UCSD, Yehuda Bock 10. California Department of Transportation, Scott Martin, Mark Turner 11. Swift Navigation, James Murphy, Grant Hausler, Rob Hranac

8 CRTN Contributing Members 1. Adkan Engineers, Tom Chrisman 2. Bock and Clark Corporation, Eric Berben 3. Burkett and Wong Engineers, Casey Lynch 4. California American Water, Stephen San Nicolas 5. Cardno Inc., Sean Fitzpatrick 6. Coast Surveying, Inc., Ken Kasbohm, Gwen del Castillo 7. Dixon Marine Services, Inc., Jeff Haran 8. East Bay Municipal Water District, Steve Martin and Tara Sweet 9. East Bay Regional Parks, Duncan Marshall 10. Helix Water District, Rebecca Vanegas 11. Honda Research Institute USA, Inc., Paul Cummings 12. Japan Aerospace Exploration Agency, Satoshi Kogure, Mike Ramirez 13. Terra-Mark Surveying, Robert Shellman 14. LocusView Solutions, Eric Gakstatter 15. MBS Land Surveys, Michael B. Stanton 16. PSOMAS, Jeremy Evans 17. Quantum Spatial, Kenny Roberts 18. Rail Surveyors and Engineers Incorporated, Cody Festa 19. RBF Consulting, Company of Michael Baker Corporation 20. RSE Inc., Cody Festa 21. Salsbury Engineering, Inc., Jon Gauthier 22. San Francisco Water Department, Edward Peterson 23. Southern California Gas Company, Gregory Irwin 24. SubCarrier Systems Corp., David Kelley 25. US Army Corps of Engineers, Ronald Spencer

9 Sample of CRTN Users An NTRIP account (username & password) is required, requested by online registration: ( 792 companies/agencies registered (up from 699 at 2016 Fall Meeting) > 25 multi-account users Recent accounts 751. U.S. Army Corps of Engineers (shoreline project) 756. Yamaha Motor Corporation (helicopter crop dusting) 759. Apollo Robotic Systems (precise UAV location) 763. Vernadero Group Inc. (rare plants survey at MCAS Miramar) 770. Brent Harvey Consulting, Inc. (golf course irrigation systems) 773. Pioneer Hi-Bred, Inc. (testing corn varieties, agricultural plots) 776. CB&I Federal Services (radiological & chemical remediation on former U.S. Navy properties) 785. City of Ventura, Water (map water meters, valves, fire hydrants) 788. Kaweah Delta Water Conservation District (subsidence mapping) 787. Jingchi Corp. (automobile industry, autonomous driving)

10 Connections to CRTN Stations through March 2017

11 CRTN Usage: Top Connections in March 2017 Total Usage: 48,238 Connections 34,395: Swift Navigation (latest CRTN Consortium Member) 1290: Javad, Bay Area 607: PrecisePositioning, San Francisco, UAV mapping for telecom industry 589: Locusview, GIS, natural gas and water 447: Jose Casanova, Southern California surveying 427: Cozad & Fox, Hemet, civil engineering, surveying 401: Yamaha Motor, Orange & Napa, crop dusting helicopter 378: Driscoll s, central California, agriculture 373: Tulare County, surveying 370: Honda, Mountainview, high precision ground-truth navigation data

12 Caltrans Task Order: New Epoch Date for California Work authorized by Mark Turner on March 16, 2016 Updated metadata for Caltrans real-time stations in SOPAC database (CVSRN, CCSRN), Bryan Banister and Eric Adney Included remaining CVSRN and CCSRN data into CRTN (collect RINEX data from all Caltrans stations and store in SOPAC archive) Added full set to Master List for processing Backfilled missing RINEX data from CVSRN Add new California stations in California (USGS, PBO, other) into the Master List for reprocessing Double check metadata and completeness of data for all stations on Master list Assign preliminary quality codes to stations Convert to ITRF2014/IGS14 through global repro Reprocess of entire California data set while continuing forward with regular SOPAC processing, in ITRF2014 reference frame

13 CSRC Epoch Date Finalized list of stations (885 active stations; 84 inactive stations) Converted to new ITRF2014/IGS14 global reference frame by reanalyzing ~400 global stations, from 1995 to transition to ITRF2014 in early 2017 Only GPS data input to the analysis Products: o List of coordinates at epoch (ITRF2014/IGS14, WGS84 geodetic, sigmas; NSRS geodetic and sigmas) o Final report, working with CRSC committee o Web posting, in progress

14 New CSRS Coordinate Epoch stations CRTN stations ITRF2008 to ITRF2014 Connect CSRS to NSRS: NAD83 (NSRS2007)? NSRS (2022)?

15 Continuous GPS stations for epoch date: ITRF2008 velocities 50 mm/yr

16 Significant Earthquakes in California

17 Detrended Displacement Time Series ( ) Coseismic & Postseismic Motions 0.16 ft 0.24 ft North DHLG GLRS CRRS East Up

18 Dynamic Datums Surveyors do not like changing reference frames and coordinates In California and other seismically active regions this is not possible. Therefore, CSRC publishes a new epoch date every few years ( , , , , ).

19 Dynamic Datums - II Reference frames need to be periodically updated to accommodate new types and number of observations and new stations. There are other phenomena other than tectonic motions that cause significant changes in coordinates (e.g., vertical land motion) requiring quality control to identify and possibly discard stations.

20 Example of Non-Tectonic Motions (Station BOMG near Salton Sea) 0.26 ft 0.11 ft 0.26 ft

21 Non-Tectonic Motions BOMG 0.26 ft 0.11 ft Waste treatment plant 0.26 ft

22 Dynamic Datums - III Creating a new epoch date for coordinates with an increase in number of stations modifies the reference system, realized through the epoch-date coordinates of the permanent GNSS stations. So does the change from, say, ITRF2008 to ITRF2014 You can think of the reference frame as a triangulated network in 2-D (or a polyhedron in 3-D) whose shape and size changes in time. The epoch-date coordinates are a snapshot at a particular epoch of time with respect to a global reference frame (ITRF2014/IGS14)

23 Dynamic Datums - IV The reference frame is defined by the positions of the permanent GNSS at a particular epoch of time (now CSRC Epoch ), and you can update CSRS station coordinates to any other epoch through, for example, SOPAC s SECTOR application. However, estimating the true-of-date coordinates of a new surveyed station with respect to the reference frame requires an additional step. There are at least two approaches: interpolation or crustal deformation model

24 SECTOR Utility Epoch-Date Coordinates

25 Interpolation Model Independent

26 Crustal Deformation Model Earthquake Cycle Elastic Rebound Theory

27 Crustal Deformation Model: Fault transects Tong et al., 2014

28 Crustal Deformation Model Coseismic Motion: 2010 Mw7.2 El Mayor-Cucapah Gonzalez et al., 2014

29 Dynamic Datums - V A GNSS survey (say RTK) is conducted at some date and positioned wrt the CSRS (say, in real time using CRTN). The surveyor receives the metadata for the reference station(s) and true-of-date ITRF coordinates as part of the RTCM3 message, consistent with the IGS frame and orbits, and estimates coordinates of surveyed marks with his/her usual field device. The true-of-date coordinates of the CRTN stations are derived using a SECTOR-type app. The surveyor can refer back to an earlier epoch date using an up-to-date HTDP-type model, which is consistent with the CSRS, since the model was derived from the CSRN coordinate time series. Whether at the survey date or an earlier date, the ITRF positions can then be converted to geodetic coordinates (say with respect to the NSRS) and then to map coordinates, if required. Is implementation and acceptance of a dynamic datum made any easier now that maps are digital, or after paper maps have been digitized?

30 Seismogeodesy: Real-time optimal integration of GNSS and seismic data in the near field of strong motion Broadband 250 Hz Singly Integrate Velocities Accelerometer Geodetic Seismogeodetic Hz Doubly Integrate Accelerations 1-10 Hz Displacements No Static Offset No Static Offset Static Offset Magnitude Saturation Clips in the near field Magnitude Saturation No Magnitude Saturation Cannot detect P wave + + Kalman Filter Advantages of Seismogeodesy Very broadband instrument that doesn t clip even in the near field of the largest earthquake Reduces baseline errors in doublyintegrated accelerometer data and preserves static offset Is not affected by regional magnitude saturation for earthquakes greater than ~M7.5 Able to detect P-wave arrivals, not possible with GNSS data alone Provides very high-rate displacement and velocity waveforms Provides two degrees of freedom (three independent observations of ground motion) Is less susceptible to false alarms for EEW

31 Real-Time Seismogeodetic Station SIO5 Mt. Soledad, La Jolla Radio Antennas GNSS Antenna/Radome Solar Panel SIO MEMS Met Sensor SIO MEMS Accelerometer GNSS Equipment Enclosures Monument Photo courtesy D. Glen Offield

32 100 Real-Time Seismogeodetic Stations in the Western U.S.: Candidates for EEW A seismogeodetic station has a GNSS/GPS and at least one seismic instrument within 2-3 km, but preferably within meters. Goldberg and Bock, JGR, 2017

33 Earthquake Early Warning: 2016 Mw5.2 Borrego Springs Earthquake Pick P waves on seismogeodetic velocities derived from GPS displacements and MEMS accelerations Goldberg and Bock, JGR, 2017

34 Extending Seismogeodesy to the Oceans: Local Tsunami Warning On-shore seismogeodetic data + Tsunami Wave Data: GNSS buoys Pressure gauges + GNSS/A Seismometers Strainmeters Earthquake Models Seafloor deformation Topography Bathymetry Tsunami Prediction Melgar & Bock, JGR, 2015

35

36 Data Gathering Satellite Orbits & Clocks

37 Data Gathering

38 Precise Point Positioning

39 Hierarchy of Warnings

40 Data and Warnings to Tsunami Warning Centers

41 Director s Report: CRTN, Epoch Update & Dynamic Datum Questions?