Updating the National Seismic Hazard Assessment. Philosophy and Implications

<div>Dam owners and operators must consider a range of hazards for the design and maintenance of infrastructure assets – including seismic hazards. In 2018, Geoscience Australia completed its National Seismic Hazard Assessment (the NSHA). This assessment used best-practice probabilistic approaches and resulted in considerably lower hazard estimates than previously considered applicable for Australia. This assessment, and subsequent site-specific assessments conducted on behalf of the dam industry have yielded divergent estimates in hazard. This has caused confusion and concern amongst the dam engineering community. Herein, we unpack the rationale for these large discrepancies, and identify best practices for the treatment of earthquake catalogues when undertaking probabilistic seismic hazard assessments for extreme-consequence facilities. A short summary of the 2023 update to the NSHA is also provided.

Presented at the 2023 Australian National Committee on Large Dams (ANCOLD) Conference

Identification info

Date (Creation): 2023-07-14T16:00:00

Date (Publication): 2024-10-30T22:02:56

Citation identifier: Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/148624

Cited responsible party

Role	Organisation / Individual Name	Details
Publisher	Commonwealth of Australia (Geoscience Australia)	Voice
Author	Allen, T.	Internal Contact
Author	Griffin, J.	Internal Contact
Author	Clark, D.	Internal Contact
Author	Ghasemi, H.	Internal Contact
Author	Cummins, P.	Internal Contact
Author	Ebrahimi, R.	Internal Contact
Author	Martin, S.	Internal Contact

Name: Australian National Committee on Large Dams (ANCOLD) Conference 25-27 October 2023, Cairns, QLD

Purpose: Conference paper - describes the rationale for changes to catalogue magnitudes in the National Seismic Hazard Assessment and provides recommendations for the Australin National Committee on Large Dams

Status: Completed

Point of contact

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

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Geoscientific information

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Maintenance and update frequency: Not planned

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Title: Product data repository: Various Formats

Protocol: FILE:DATA-DIRECTORY

Name of the resource: Data Store directory containing the digital product files

Description: Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes

Project

seismic hazard
NSHA
earthquake catalogue

Keywords

seismic hazard assessment

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NSHA

Keywords

earthquake catalogue

theme.ANZRC Fields of Research.rdf

Seismology and Seismic Exploration

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Published_External

Resource constraints

Title: Creative Commons Attribution 4.0 International Licence

Alternate title: CC-BY

Edition: 4.0

Website

https://creativecommons.org/licenses/by/4.0/

Addressee

Role	Organisation / Individual Name	Details
User	Any

Use constraints: License

Use constraints: Other restrictions

Other constraints: © Commonwealth of Australia (Geoscience Australia) 2023

Resource constraints

Title: Australian Government Security Classification System

Edition date: 2018-11-01T00:00:00

Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification: Unclassified

Classification system: Australian Government Security Classification System

Associated resource

Association Type: Had derivation

Title: The 2018 National Seismic Hazard Assessment: Model overview

Citation identifier: 123020

Citation identifier: 9456a1ee-400d-43fa-bce3-58d1cd8cdf55

Website

http://pid.geoscience.gov.au/dataset/ga/123020

Link to eCat metadata record landing page

Associated resource

Association Type: Had derivation

Title: The 2018 national seismic hazard assessment of Australia: Quantifying hazard changes and model uncertainties

Citation identifier: 126324

Citation identifier: 9d84d182-eb0d-4637-b5cd-580b7da85cde

Website

http://pid.geoscience.gov.au/dataset/ga/126324

Link to eCat metadata record landing page

Language: English

Character encoding: UTF8

Distribution Information

Distributor contact

Role	Organisation / Individual Name	Details
Distributor	Commonwealth of Australia (Geoscience Australia)	Voice facsimile

Distribution format

OnLine resource: Link to Paper

Link to Paper

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OnLine resource: Related Record: The 2023 National Seismic Hazard Assessment for Australia. Model Overview

Related Record: The 2023 National Seismic Hazard Assessment for Australia. Model Overview

Distribution format

OnLine resource: Related Record: The 2023 National Seismic Hazard Assessment of Australia Rationale for changes in hazard

Related Record: The 2023 National Seismic Hazard Assessment of Australia Rationale for changes in hazard

Distribution format

OnLine resource: Related Record: The 2023 National Seismic Hazard Assessment for Australia. Model Input and Output Data

Related Record: The 2023 National Seismic Hazard Assessment for Australia. Model Input and Output Data

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Statement: <div>Extends knowledge developed through the 2018 National Seismic Hazard Assessment</div>

Metadata constraints

Title: Australian Government Security Classification System

Edition date: 2018-11-01T00:00:00

Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification: Unclassified

Metadata

Metadata identifier

urn:uuid/d16b3bf1-fd3a-4dfd-b1af-3e917a7bf10c

Title: GeoNetwork UUID

Language: English

Character encoding: UTF8

Contact

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: Journal Article / Conference Paper

Alternative metadata reference

Title: Geoscience Australia - short identifier for metadata record with uuid

Citation identifier: eCatId/148624

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng/catalog.search#/metadata/d16b3bf1-fd3a-4dfd-b1af-3e917a7bf10c

Date info (Creation): 2025-04-14T06:16:43.957Z

Date info (Creation): 2024-08-05T04:28:15

Date info (Revision): 2025-04-14T06:16:57.873Z

Metadata standard

Title: AU/NZS ISO 19115-1:2014

Metadata standard

Title: ISO 19115-1:2014

Metadata standard

Title: ISO 19115-3

Title: Geoscience Australia Community Metadata Profile of ISO 19115-1:2014

Edition: Version 2.0, September 2018

Citation identifier: http://pid.geoscience.gov.au/dataset/ga/122551

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Read here the full details and access to the data.

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