{"id":23691329,"url":"https://github.com/usgs/nshm-ak-2007","last_synced_at":"2026-02-17T07:09:12.728Z","repository":{"id":146383353,"uuid":"46445410","full_name":"usgs/nshm-ak-2007","owner":"usgs","description":"NSHM: Alaska 2007","archived":false,"fork":false,"pushed_at":"2022-12-08T19:35:41.000Z","size":4436,"stargazers_count":4,"open_issues_count":0,"forks_count":5,"subscribers_count":8,"default_branch":"main","last_synced_at":"2025-05-22T08:34:27.324Z","etag":null,"topics":["earthquake-hazard","earthquake-source","earthquake-source-characterization","nshmp-haz","psha","seismic-hazard","seismic-source","usgs"],"latest_commit_sha":null,"homepage":"","language":null,"has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"other","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/usgs.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE.md","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2015-11-18T20:27:23.000Z","updated_at":"2023-02-21T10:48:08.000Z","dependencies_parsed_at":null,"dependency_job_id":"ef2eb9fa-4c2b-4f9f-91c3-7218f27c2836","html_url":"https://github.com/usgs/nshm-ak-2007","commit_stats":null,"previous_names":[],"tags_count":3,"template":false,"template_full_name":null,"purl":"pkg:github/usgs/nshm-ak-2007","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/usgs%2Fnshm-ak-2007","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/usgs%2Fnshm-ak-2007/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/usgs%2Fnshm-ak-2007/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/usgs%2Fnshm-ak-2007/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/usgs","download_url":"https://codeload.github.com/usgs/nshm-ak-2007/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/usgs%2Fnshm-ak-2007/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":259650956,"owners_count":22890385,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["earthquake-hazard","earthquake-source","earthquake-source-characterization","nshmp-haz","psha","seismic-hazard","seismic-source","usgs"],"created_at":"2024-12-30T02:56:34.787Z","updated_at":"2025-10-13T09:09:20.030Z","avatar_url":"https://github.com/usgs.png","language":null,"funding_links":[],"categories":[],"sub_categories":[],"readme":"## NSHM: Alaska 2007\n\n**NOTE: This model is preliminary and for review purposes only. It is intended for use with an updated USGS earthquake hazards codebase: [nshmp-haz](https://github.com/usgs/nshmp-haz). It is currently under review and does NOT represent an official release or product. For official release products please see the [USGS Earthquake Hazards](http://earthquake.usgs.gov/hazards/) website.**\n\nFor details on the format of this U.S. Geological Survey (USGS) National Seismic Hazard Model (NSHM), see the [nshmp-haz wiki](https://github.com/usgs/nshmp-haz/wiki).\n\nSee also the [2007 USGS Alaska Earthquake Hazard Maps \u0026 Data](http://earthquake.usgs.gov/hazards/products/ak/).\n\n### Implementation Details\n\nNotable implementation details (in fortran source and inputs) that set Alaska 2007 apart from later COUS models and this updated nshmp-haz implementation of the Alaska model:\n\n* Grid and slab optimization tables use discretization of 2km out to 200km.\n  * nshmp-haz: __discretization = 1km__\n* Grid and slab sources use the Wells \u0026 Coppersmith (1994) magnitude-length scaling relation.\n  * nshmp-haz: __slab sources use Youngs et al. (1997)__ (aka 'geomatrix'; consistent with 2014 COUS NSHM)\n* Grid and slab sources randomize strike at M≥6.\n  * nshmp-haz: __uses point-source distance corrections for M≥6__ (in relations above; consistent with 2014 COUS NSHM)\n* Ground motion models do not impose one-sided 3σ upper truncation on exceedances.\n  * nshmp-haz: __no change__\n* Other details:\n  * nshmp-haz: __grid source maxDepth = 15 km__\n* Focal mechansim variations are encoded into coefficients supplied with each input file; flavors for strike-slip and mixed strike-slip/reverse were ported from the 2002 COUS model.\n  * nshmp-haz: __point sources generate focal mechanism specific ruptures with appropriate rake that are processed independently, consistent with 2014 COUS NSHM__\n* Aleatory uncertainty was added in the 2002 COUS model and was carried over here as a moment-balanced Gaussian distribution on mMax of M±0.15 discretized over 5 values with σ=0.12. The 2008 COUS model increased the width of the distribution to M±2σ and increased the discretization to 11 values. Both implementations require custom code; the more recent approach is more straightforward with the distribution a function of σ.\n  * nshmp-haz: __uses more recent (11-point; ±2σ) aleatory uncertainty model__\n* Hazard curves are not truncated at 3σ.\n  * nshmp-haz: __no change__\n\n### Other Notes\n\n* Consistent with 2008 and 2014 COUS models, slab and grid Gutenberg-Richter MFD magnitudes bins are centered on 0.05; interface MFD bins are centered on 0.1.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fusgs%2Fnshm-ak-2007","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fusgs%2Fnshm-ak-2007","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fusgs%2Fnshm-ak-2007/lists"}