infrasound workshop san diego, usa 27-30 october 2003 infrasound processing at the idc and its...

Infrasound WorkshopSan Diego, USA27-30 October 2003

Infrasound Processing at the IDC and its Near-term Development

P. Firbas, N. BrachetInternational Data CentreWaveform Development and Software Integration Section

Preparatory Commission for the ComprehensiveNuclear-Test-Ban Treaty OrganizationProvisional Technical SecretariatVienna International CentreP.O. Box 1200, A-1400 Vienna, AustriaE-mail: [email protected]: [email protected]

Infrasound Workshop in San Diego, USA 27-30 October 2003

Outline of the Talk

• Introduction

• IDC processing - current status

• Software development and tuning

• Infrasound contracts in 2003

• Summary


Introduction

• Follow the guidelines from CTBT/WGB/TL-2/79 (Sept2003)

Significant effort should be directed into assessment and further development of infrasound tools for analysis. It is recognized that some existing tools (e.g. PMCC) show considerable potential for forming the basis for infrasound analysis, but are not yet in a form suitable for routine operations.

• Continuity with the work being accomplished

– Understand the infrasound signals with station monitoring

– Assess the capabilities and limitations of the current software

– Propose design for enhanced automatic and interactive software at the IDC

– Test and implement new tools


IDC Processing - Current Status

Operations: 11 infrasound arrays (+6 in 2003)

Testbed: 16 infrasound arrays (+4 in 2003)

IMS Infrasound arrays processed at the IDC (as of 22 October 2003)


I26,

I10

I07,

I10

I34

I34

I07

I33

I26

I59

I59

I57 I0

8 I24

I24,

I33 I0

8 I17

I22,

I31

I17 I1

8 I31 I2

2

I55

I09,

I53

SEL3 events with infrasound phases

0

100

200

300

400

500

600

Apr01May01Jun01Jul01Aug01Sep01Oct01Nov01Dec01Jan02Feb02Mar02Apr02May02Jun02Jul02Aug02Sep02Oct02Nov02Dec02Jan03Feb03Mar03Apr03May03Jun03Jul03Aug03Sep03

Testbed Operations



Types of phases contributing to infrasound automatic events (SEL3)

Situation in Sept 2002 Situation in Sept 2003

Ope

rati

ons

Tes

tbed

315 events

433 events

1910 events

4716 events



Types of phases contributing to infrasound automatic events


S. hemisphere marine storms


SEL3 infrasound events

7 infrasound arrays

461 events in 2002

IDC OPERATIONS: 2002


4 infrasound arrays

61 events





16 infrasound arrays

4384 events

IDC TESTBED: 2003


11 infrasound arrays

1743 events




(Alarming) Summary about automatic infra events at the IDC

• 2002 - 2003 statistics (period January-October)

• 4 infrasound arrays added to the Operational IDC processing (7->11).

• The number of SEL3 events multiplied by 6 (280 -> 1743).

• Near Future: IDC Testbed vs Operations

• 5 (4, excluding I57US) new arrays processed on Testbed (11 -> 16)

• The number of SEL3 events multiplied by 2.5 (1743 -> 4384).

• Long term: IDC operations using a complete IMS network

• 44 infrasound arrays to be added in IDC processing

• Reviewed Event Bulletin (REB)

Of 1743 SEL3 events including infrasound arrival(s), only 4 made it to the REB

• 1 N. Pacific Ocean storm: 3 Infra phases (I10CA, I34MN, I59US),

• 3 earthquakes: (Australia mb4.4, Algeria mb5.6, Hawaii mb4.5) 1 Infra phase



14 J

uly

2002

27 D

ec 2

002

N. Hemisphere

S. Hemisphere

IDC Processing - Annual Overview


Weekly DFX-PMCC detection bulletin at I53US

Daily Libinfra/PMCC detectionsI53US, 2003/09/22

IDC Processing - Weekly and Daily Overview


Automatic Detection Processing• IDC Operational software: DFX-libinfra

• Development and testing of DFX-PMCC software

Software Development and Tuning

Cou

nt

9045 225135 180 270 315 360

I34MN, 18Jan2003

0

I34MN, 18Jan2003

Cou

nt

45 90 135 180 225 270 315 3600


Automatic Detection Processing (Cont.)

• Accomplishments

– Comparison of the daily detections produced by DFX-libinfra DFX-PMCC

– DFX-PMCC source code modified and substantially improved

– DFX-PMCC results synchronized with WinPMCC results: high level of confidence in the detection capability and quality

– Baseline configuration established for DFX-PMCC

– DFX-PMCC ready to be implemented and tested on real-time processing (IDC Testbed)



Reduce the number of bogus events related to microbaroms/surfIdentify the type of station-event based on the signal characteristics

• Azimuth stability or slightly variable with time

• Series of detections distributed over a long time period

• Frequency content on a narrow band centered around 0.15 Hz• The quality of the detections is a key factor to allow the signal identification

Example of microbaroms recorded at I34MN on January 18, 2003

Example of surf noise recorded at I59US on October 12, 2003



Automatic Global Association Processing (GA)Decrease the number of HI bogus events (36% of total infra events)Disable in GA the possibility of using HI seed associations (R. Le Bras)


Period 20 Sep 2003 - 8 Oct 2003

After changes in GABefore changes in GA



Interactive Processing at the IDC

• Software installation and testing at the IDC– 2001: WinPMCC (developed by DASE, France) delivered to the IDC

– 2002: WinPMCC tested and validated at the IDC

• Design of the future IDC interactive software for infrasound signal analysis

– Use WinPMCC experience for prototyping the future IDC infrasound interactive software

– Use the efficient cross-correlation/consistency algorithm

– Need a 3D colored representation for the derived data (azimuth, speed, consistency ...)



Interactive Processing at the IDC (Cont.)

• Plans for the future IDC infrasound interactive software

– Continue to use ARS for infrasound interactive review

– Bypass the graphic limitation of ARS introducing a new tool that has the capability of displaying 3D information (PMCC pixels) in order to review infrasound signals

– Geotool window would be the best candidate to supplement ARS and support PMCC-type display

Geotool offers a good comfort for displaying color information in addition to the waveforms and arrivals. Geotool is also fully integrated with CSS database.

– Geotool-PMCC would display the derived information calculated by the automatic processing (DFX-PMCC)


Proposed Design for IDC infrasound processing

Database

Automatic processingDFX-PMCC

PMCC output files

ARS

Interactive processing


Geotool-PMCC


Infrasound contracts in 2003

Request for ProposalEstablishment of an Infrasound Reference Database and Support for Enhancement of Infrasound Data Processing, Phase 1

• TOR task 2: Collection of reference events and noiseCollection of infrasonic reference event data and noise generated by a wide variety of natural and artificial sources from different regions of the world, preferably recorded using modern instrumentation similar to that used at the IMS stations, including the relevant meta-data and along with results of expert analysis.

• TOR task 4: Automatic and interactive processing Automatic and/or interactive processing of selected continuous I data (from IMS stations) provided by the IDC.

• TOR task 8: Travel-time tablesGeneration of seasonally (monthly), or if essential, diurnally varying and azimuth and range dependent travel-time tables for IMS I stations and relevant algorithms/software.



• Contract with DASE (France), task 2,4– Continuation for Year 2, signed in April 2003 – Comprehensive analysis of continuous data at I08BO (Bolivia) and I24FR (Tahiti)– Semi-annual report (task4) delivered

• Contract with ANU (Australia), task 4– Contract signed in May 2002– Develop an advanced infrasound signal processing method using

• 3D slowness-space correlator • Basic pattern recognition system for detecting regions of consistent azimuth

– Noise field characterisation– Automatic and interactive processing of selected continuous infrasound data

(I07AU, I10CA, I26DE, I33MG, I34MN, I59US) - Software and reports in final stages



• Contract with University of Alaska Fairbanks (USA), task2– Signed in November 2002– Collect and process reference events at I53US (Alaska) and I55US (Antarctica)– Semi-annual report delivered

• Contract with UCSD (USA), task2– Signed in July 2003– Collect and process reference events at I57US (California)

• Contract with ISLA (Hawaii), task8– Signed in June 2003– Tau-P travel-time calculator, GUI interface with SAGE-RT* meteorological data

from Naval Research Laboratory (NRL), USA

* SAGE-RT: Specification of the Atmosphere from the Ground to the Exosphere - real Time


Summary

IDC current and near-future objectives

WGB-TL-2/79: Given the current lack of operational analysis capability, the group recommends that no attempts should be made in the short term to include infrasound into the routine analyst review, and that the automated operational processing of infrasound data may need to be suspended.

• Automatic Detection Processing: Improve the automatic detection bulletin to a high level of confidence and quality (DFX-PMCC)

• Phase identification: identify phases related to known categories of long duration events (microbaroms, surf noise) and exclude them from the automatic event association

• Event building: Limit building large amount of false events by configuring GA

• Interactive processing: Provide the IDC analysts with a suitable infrasound specific interactive tool (Geotool-PMCC)

• IDC systems configuration: [Follow WGB-TL-2/79] Suspend temporarily infrasound network processing on OPS, keep it on Testbed where DFX-PMCC will be tested

infrasound workshop san diego, usa 27-30 october 2003 infrasound processing at the idc and its...

Documents

infrasound processing

sel3 infrasound events

infrasound analysis

infrasound signals

infrasound workshop

events idc operations

ims infrasound arrays

events idc testbed