Product catalogue
Evaluation of the NSHA23 Magnitude Conversion Equations Using a New Moment Magnitude Catalogue
<div>An earthquake catalogue based on the moment magnitude scale (<em>M</em>W) is a prerequisite for global best practice seismic hazard analyses. The 2018 National Seismic Hazard Assessment (NSHA18) was the first national-scale seismic hazard assessment for Australia to apply magnitude conversions to express earthquake magnitudes uniformly in terms of <em>M</em>W. This approach led to the single-biggest change in seismic hazard estimates between Geoscience Australia-led national seismic-hazard models. Between the 2012 and 2018 assessments, the hazard reduced because of: 1) the general reduction in the number of earthquakes of magnitude 4.0 and larger due to the correction of local magnitudes (<em>M</em>L) and subsequent conversion to <em>M</em>W, and; 2) the increase in the Gutenberg-Richter <em>b</em>-value due to the non-linear conversion of local magnitudes <em>M</em>L to <em>M</em>W.</div><div>Using a new continental-scale attenuation model, independent assessment of <em>M</em>W has been performed for over 300 earthquakes recorded between 1990 and September 2024. After recalculating <em>M</em>L for the same earthquakes using improved filtering and time-domain windowing criteria, the <em>M</em>W catalogue is used to test and validate the <em>M</em>L to <em>M</em>W conversion equations used in the 2023 National Seismic Hazard Assessment (NSHA23). The earthquakes are partitioned into their regional magnitude polygons as applied by Geoscience Australia in its real-time operations; notionally central and western Australia, South Australia (Mt Lofty and Flinders Ranges) and eastern Australia. The performance NSHA23 <em>M</em>L to <em>M</em>W conversion equation is then assessed for each of these magnitude regions. Overall, the NSHA23 <em>M</em>L to <em>M</em>W conversion performs very well relative to continental-scale earthquake dataset. The sensitivity of this conversion to an earthquake’s static stress drop is also assessed. There is evidence that minor adjustments could be applied to the NSHA23 <em>M</em>L–<em>M</em>W conversion equation for larger-magnitude events with high stress drops.</div><div><br></div> Presented at the Australian Earthquake Engineering Society (AEES) National Conference 2024
Simple
Identification info
- Date (Creation)
- 2024-09-27T16:00:00
- Date (Publication)
- 2024-12-16T23:45:29
- Citation identifier
- Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/149927
- Cited responsible party
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Role Organisation / Individual Name Details Publisher Commonwealth of Australia (Geoscience Australia)
Voice Author Allen, T.I.
External Contact
- Name
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Australian Earthquake Engineering Society (AEES) National Conference, Novermber 21-23 2024, Adelaide, SA
- Purpose
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Reviews the performance of the 2023 National Seismic Hazard Assessment's magnitude conversion equations
- Status
- Completed
- Point of contact
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Role Organisation / Individual Name Details Resource provider Place and Communities Division
External Contact Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Allen, T.
Internal Contact
- Spatial representation type
- Topic category
-
- Geoscientific information
Extent
))
- Maintenance and update frequency
- Not planned
Resource format
- Title
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Product data repository: Various Formats
- Website
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Data Store directory containing the digital product files
Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes
- Project
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2023 National Seismic Hazard Assessment
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- Keywords
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earthquake catalogue
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- Keywords
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magnitude conversion
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- Keywords
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seismic hazard assessment
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- theme.ANZRC Fields of Research.rdf
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Seismology and Seismic Exploration
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- Keywords
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Published_External
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Resource constraints
- Title
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Creative Commons Attribution 4.0 International Licence
- Alternate title
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CC-BY
- Edition
-
4.0
- Access constraints
- License
- Use constraints
- License
- Other constraints
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© Commonwealth of Australia (Geoscience Australia) 2024
Resource constraints
- Title
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Australian Government Security Classification System
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
- Classification system
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Australian Government Security Classification System
Associated resource
- Association Type
- Was informed by
- Title
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The 2023 National Seismic Hazard Assessment for Australia. Model Overview
- Citation identifier
- 148969
- Citation identifier
- 86d9ffcf-8bbf-4aad-b6c4-70fcae2be457
- Language
- English
- Character encoding
- UTF8
Distribution Information
- Distributor contact
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Role Organisation / Individual Name Details Distributor Commonwealth of Australia (Geoscience Australia)
Voice facsimile
- OnLine resource
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Link to conference paper
Link to conference paper
- Distribution format
-
- OnLine resource
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Link to conference page
Link to conference page
- Distribution format
-
Resource lineage
- Statement
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<div>Reviews the performance of the 2023 National Seismic Hazard Assessment magnitude conversion equations</div>
Metadata constraints
- Title
-
Australian Government Security Classification System
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
Metadata
- Metadata identifier
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urn:uuid/5caf387d-a98f-48f4-862f-7dd3297d8027
- Title
-
GeoNetwork UUID
- Language
- English
- Character encoding
- UTF8
- Contact
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Role Organisation / Individual Name Details Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Allen, T.
Internal Contact
Type of resource
- Resource scope
- Document
- Name
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Journal Article / Conference Paper
Alternative metadata reference
- Title
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Geoscience Australia - short identifier for metadata record with
uuid
- Citation identifier
- eCatId/149927
- Date info (Creation)
- 2024-12-16T01:19:10
- Date info (Revision)
- 2024-12-16T01:19:10
Metadata standard
- Title
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AU/NZS ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-3
- Title
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Geoscience Australia Community Metadata Profile of ISO 19115-1:2014
- Edition
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Version 2.0, September 2018
- Citation identifier
- http://pid.geoscience.gov.au/dataset/ga/122551