SOURCES SOUGHT
B -- SOURCES SOUGHT ONLYInversion Data-based Q-determinations, S-wave Velocities, P-wave Velocities, Seismic Reflection Surveys, Seismic Refraction Tomography Surveys, Multichannel Analysis of Surface Waves (MASW) Surveys
- Notice Date
- 7/12/2011
- Notice Type
- Sources Sought
- Contracting Office
- Bureau of Reclamation-DO-Acquisition Operations Group PO Box 25007, 84-27810 Denver CO 80225
- ZIP Code
- 80225
- Solicitation Number
- R11PS81160
- Response Due
- 7/18/2011
- Archive Date
- 7/11/2012
- Point of Contact
- Carol Ditmer Contract Specialist 3034452403 cditmer@usbr.gov;
- E-Mail Address
-
Point of Contact above, or if none listed, contact the IDEAS EC HELP DESK for assistance
(EC_helpdesk@NBC.GOV)
- Small Business Set-Aside
- N/A
- Description
- Please respond to cditmer@usbr.gov with company name, DUNS #, POC name, email address, and phone number. 1.0Background: 1.1The subject dam and its foundation are undergoing analyses for predicted earthquake ground motions and accelerations. As part of these analyses, compression (P-wave) and shear (S-Wave) common mid-point seismic reflection, P-wave and S-wave seismic refraction tomography, and Multichannel Analysis of Surface Wave (MASW) surveys are required at the downstream toe area of the dam. This survey data will provide input for inversion-based P-wave and S-wave velocity and Q-factor (Vp, Vs, Qp, Qs) 1.2This requirement specifies conducting seismic surveys for the purpose of delineating several subsurface earth properties including P-wave and S-wave velocity and Q-factor (Vp, Vs, Qp, Qs), seismic layer orientation, and thickness. It requires seismic P- and S-wave reflection profiling, multichannel analysis of surface waves (MASW), and seismic refraction tomography profiling in specific areas of the dam. Profile lines would be conducted on Reclamation-owned or county roads. It is anticipated that approximately 2 km (1.6 mi) of seismic profiling would be conducted on each of two profile lines, one near dam station 560+00 and the other near dam station 730+00 for a total of approx 4 km (3.2 mi) of profiling. 2.0Technical Requirements: 2.1The Contractor shall perform seismic P- and S-wave reflection profiling using nominal 3-meter (10-foot) receiver spacing, 6-meter (20-foot) source point spacing, utilizing 480 channel acquisition system (Geometrics Geode / StrataVisor or 100% equivalent at the signal level and binary file level). 2.2Contractor shall utilize hydraulic-based vibratory seismic source system for all seismic reflection survey work under this requirement. Source sweep parameters for each profile and each vibrator source orientation (horizontal or vertical) shall be determined on the initial testing at each profile and source type. The same physical vibratory seismic source unit shall be used for all seismic reflection data acquisition work, by varying the mass/plate/vibrator configuration. All vibratory sweeps shall be recorded by separate accelerometers on the mass and on the baseplate, and shall be submitted as part of the data deliverables along with observer's logs documenting the filename to source/receiver geometry correspondence. All seismic data recorded as part of this contract shall be recorded and stored uncorrelated. All of the uncorrelated raw files shall be submitted as part of the data deliverables along with observer's logs as mentioned above. 2.3All seismic reflection profiles (P- & S-) shall be acquired to obtain subsurface layer velocity information to a depth of approximately 750-1000 meters (2,460-3,280 feet) below ground surface from observable reflecting horizons. 2.4Contractor shall perform QC processing on a daily basis during seismic profile work to insure that survey objectives are being met. 2.5Contractor shall perform MASW profiling along coincident line as the reflection profile lines, and shall acquire data in such fashion as to yield fundamental and higher mode dispersion curves capable of being inverted into S-wave velocity data in the 0-30 m (0-100 ft) range. Contractor shall use mechanical, accelerated weight-drop impact seismic source to generate frequencies low enough to image to the desired 30 m below ground surface. The accelerated weight drop shall be tuned to produce high signal-to-noise ratio and high bandwidth in the 5 to 8 Hz range (lower spectral components). All MASW profiles shall be acquired to obtain data-based inversion Q-factor values to a depth of approximately 30 m (100 ft) below ground surface. 2.6Contractor shall perform P- and S-wave refraction tomography using above mentioned mechanical accelerated weight drop seismic source, along coincident lines as the reflection and MASW profile lines, and shall acquire data in such fashion as to be able to invert reflection, MASW, and refraction data in the 0-30 m (0-100 ft) range, where applicable, to improve imaging over the 0-1000 m reflection depth section and the 0-30 m MASW depth section. 2.7Along the seismic profiles, the Contractor shall measure source and receiver ground locations by means of GPS-RTK, or other method as approved by COR. 2.8Contractor shall process P- and S-wave reflection data in such fashion as to be able to accurately estimate and provide uncertainty in Vp, Vs parameters versus line station and depth.2.9Contractor shall process MASW data in such fashion as to be able to accurately estimate and provide uncertainty in Qp, Qs parameters versus line station and depth for all profiles collected. Contractor shall use actual on-site data collected under this contract to perform inversion-based Vp, Vs, Qp, Qs determinations. 3.0Deliverables 3.1 The Contractor shall prepare the following: 3.1.1 A discussion of the surveys performed, survey locations, data acquisition parameters, and interpretation procedures used. The description of the interpretation methods used shall include references to journal or other sources describing the basis for the numerical modeling and interpretation.3.1.2 A discussion of the survey results, including profiles of measured seismic velocities and Q values (Vp, Vs, Qp, Qs.). This discussion shall also include estimates of the quality or estimated errors in the measured or modeled results. 3.1.3Data appendices (may be electronic files on DVD or CD) containing raw uncorrelated vibrator sweep data, mass and vibrator plate accelerometer data, observer's logs, GPS/RTK files, and data files developed as part of the data reduction and interpretation work.
- Web Link
-
FBO.gov Permalink
(https://www.fbo.gov/notices/d2391d3db80f598f1e92254e529a0716)
- Place of Performance
- Address: Denver Federal Center, Denver, CO
- Zip Code: 80225
- Zip Code: 80225
- Record
- SN02496740-W 20110714/110712235621-d2391d3db80f598f1e92254e529a0716 (fbodaily.com)
- Source
-
FedBizOpps Link to This Notice
(may not be valid after Archive Date)
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