Slide 1

Industry-style combined active/passive dense array surveys: directions and issues. Dan Hollis, NodalSeismic, LLC 26 January 2014Active Source Workshop

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Road Map Continuous Seismic Data Recording in Active Source Surveys Equipment Operations Long Beach 3D Survey Description Lessons Learned Modifications for Enhancing Passive Component Santa Fe Springs 3D Generic Concept Fisher County 3D Data Products Issues Going Forward Conclusions/Questions 26 January 2014Active Source Workshop

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Autonomous Node System 26 January 2014Active Source Workshop Spike Internal Geophone Element (10 Hz, vertical) NAND Flash Memory Li-ion Batteries 2-week life @ 24/7 (5-week model in Q4 13) GPS Receiver 24-bit A/D Convertor Controller-processor

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26 January 2014Active Source Workshop Autonomous Node System GEN-2, 3-C 3 component 30-day battery life @ 24/7 1.8 kilograms

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Traditional 3D Recording Array and Operations 26 January 2014Active Source Workshop 300 square mile survey (10 x 30) 1320 RLS & 220 RI (dark blue) Nominal 18x100 Active Recording Patch (light blue)

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Receiver Array Flexibility 26 January 2014Active Source Workshop Traditional - 990 RLS x 110 RIRURA - 330 RLS x 330 RI Both designs are about 256 receivers per square mile

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Road Map Continuous Seismic Data Recording in Active Source Surveys Equipment Operations Long Beach 3D Survey Description Lessons Learned Modifications for Enhancing Passive Component Santa Fe Springs 3D Generic Concept Fisher County 3D Data Products Issues Going Forward Conclusions/Questions 26 January 2014Active Source Workshop

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Long Beach 3D Seismic Survey 26 January 2014Active Source Workshop -5400 receivers/nodes (static) -Spacing ~100m inline & X-line -24 hr/day, 7 day/week recording -Active sourcing weekdays and Sunday morning -2 ms sample interval -3 Hz low cut filter -10 Hz CT-30 geophone (vertical)

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Long Beach 3D Passive Seismic Dataset ~ 6 month duration ~ 150 TB of data Several significant local events Teleseismic events (March 11, 2011 Japan earthquake) Passive Data Analyses Ambient Noise Correlation Receiver function Travel-time tomography Microseismic 26 January 2014Active Source Workshop

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Carson EQ -12 Hz HC 26 January 2014Active Source Workshop

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Long Beach 3D Lessons Learned Preserving continuous data Frequency response and instrument filters Uniform vs traditional receiver arrays Survey Design Considerations Stations external to survey to reduce edge effects with ambient noise correlation analysis Larger size surveys, insufficient equipment to cover entire survey 26 January 2014Active Source Workshop

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Edge Effects - Anisotropic Velocity Variations 1.25 Hz1.00 Hz Azimuth 1.0 Hz 17 December 2013Shell Lunch-n-Learn

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Road Map Continuous Seismic Data Recording in Active Source Surveys Equipment Operations Long Beach 3D Survey Description Lessons Learned Modifications for Enhancing Passive Component Santa Fe Springs 3D Generic Concept Fisher County 3D Data Products Issues Going Forward Conclusions/Questions 26 January 2014Active Source Workshop

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6 km 26 January 2014Active Source Workshop Santa Fe Springs 3D

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Generic Concept Outliers Active Source Patch Backbone Array Conventional survey outline 26 January 2014Active Source Workshop

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Fisher Co, TX 3D Active Source Receiver Array 26 January 2014Active Source Workshop

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Fisher Co, TX 3D Outlier and Backbone Array 26 January 2014Active Source Workshop

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Fisher Co, TX 3D Proposed Broadband Array 26 January 2014Active Source Workshop

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Road Map Continuous Seismic Data Recording in Active Source Surveys Equipment Operations Long Beach 3D Survey Description Lessons Learned Modifications for Enhancing Passive Component Santa Fe Springs 3D Generic Concept Fisher County 3D Data Products Issues Going Forward Conclusions/Questions 26 January 2014Active Source Workshop

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Data Products (and Formats) Active Receiver Patch Shot Slice Data SEG-Y Active Receiver Patch Continuous Data SEG-D Outliers and Backbone Array SEG-D Shot Timing/Location Data SBS OB Logs Survey Data SEG-P1 26 January 2014Active Source Workshop

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Road Map Continuous Seismic Data Recording in Active Source Surveys Equipment Operations Long Beach 3D Survey Description Lessons Learned Modifications for Enhancing Passive Component Santa Fe Springs 3D Generic Concept Fisher County 3D Data Products Issues Going Forward Conclusions/Questions 26 January 2014Active Source Workshop

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Issues Going Forward Data format for continuous data. SEG-D not common for long record lengths. 26 January 2014Active Source Workshop

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Questions 26 January 2014Active Source Workshop