{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1361137046103370112.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1190/1.1444214"}},{"identifier":{"@type":"URI","@value":"https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/62/4/1132/3172887/1132.pdf"}}],"dc:title":[{"@value":"3-D magnetic imaging using conjugate gradients"}],"description":[{"type":"abstract","notation":[{"@value":"<jats:title>Abstract</jats:title>\n                  <jats:p>A 3-D inversion approach is outlined that determines a distribution of susceptibility that produces a given magnetic anomaly. The subsurface model consists of a 3-D array of rectangular blocks, each with a constant susceptibility. The inversion incorporates a model norm that allows smoothing and depth-weighting of the solution. Since the number of parameters can be many thousands, even for small problems, the linear system of equations is inverted using a preconditioned conjugate gradient approach. This reduces memory requirements and avoids large matrix multiplications. The method is used to determine the 3-D susceptibility distribution responsible for the Temagami magnetic anomaly in southern Ontario, Canada.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1381137046103370112","@type":"Researcher","foaf:name":[{"@value":"Mark Pilkington"}],"jpcoar:affiliationName":[{"@value":"Geological Survey of Canada, Ottawa, ON, Canada"}]}],"publication":{"publicationIdentifier":[{"@type":"EISSN","@value":"19422156"},{"@type":"PISSN","@value":"00168033"}],"prism:publicationName":[{"@value":"Geophysics"}],"dc:publisher":[{"@value":"Society of Exploration Geophysicists"}],"prism:publicationDate":"1997-08-01","prism:volume":"62","prism:number":"4","prism:startingPage":"1132","prism:endingPage":"1142"},"reviewed":"false","url":[{"@id":"https://pubs.geoscienceworld.org/seg/geophysics/article-pdf/62/4/1132/3172887/1132.pdf"}],"createdAt":"2002-10-11","modifiedAt":"2025-12-11","relatedProduct":[{"@id":"https://cir.nii.ac.jp/crid/1050845763318233472","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"3-D inversion of magnetic data based on the L1-L2 norm regularization"}]},{"@id":"https://cir.nii.ac.jp/crid/1360013168799766656","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Magnetic inversion to recover the subsurface block structures based on<i>L</i>1 norm and total variation regularization"}]}],"dataSourceIdentifier":[{"@type":"CROSSREF","@value":"10.1190/1.1444214"},{"@type":"CROSSREF","@value":"10.1093/gji/ggab355_references_DOI_PB0Ogfk3wFvWWAMhdhTKbTRo5Ar"},{"@type":"CROSSREF","@value":"10.1186/s40623-019-1052-4_references_DOI_PB0Ogfk3wFvWWAMhdhTKbTRo5Ar"}]}