{"id":730,"date":"2025-11-12T15:53:56","date_gmt":"2025-11-12T15:53:56","guid":{"rendered":"https:\/\/www.finitesource.com\/senza-categoria\/from-ground-deformation-to-faulting\/"},"modified":"2025-12-09T14:09:08","modified_gmt":"2025-12-09T14:09:08","slug":"from-ground-deformation-to-faulting","status":"publish","type":"post","link":"https:\/\/www.finitesource.com\/en\/insights\/from-ground-deformation-to-faulting\/","title":{"rendered":"From ground deformation to faulting"},"content":{"rendered":"<section class=\"l-section wpb_row us_custom_9acb681f height_auto width_full\"><div class=\"l-section-overlay\" style=\"background:#20232D\"><\/div><div class=\"l-section-h i-cf\"><div class=\"g-cols vc_row via_grid cols_2 laptops-cols_inherit tablets-cols_inherit mobiles-cols_1 valign_top type_default stacking_default\"><div class=\"wpb_column vc_column_container us_custom_dffb9c9b has_bg_color\"><div class=\"vc_column-inner\"><\/div><\/div><div class=\"wpb_column vc_column_container\"><div class=\"vc_column-inner\"><div class=\"w-separator size_large\"><\/div><div class=\"w-post-elm post_taxonomy style_badge color_link_inherit\" id=\"chips\"><a class=\"w-btn us-btn-style_5 term-32 term-insights\" href=\"https:\/\/www.finitesource.com\/en\/category\/insights\/\"><span class=\"w-btn-label\">Insights<\/span><\/a><\/div><div class=\"w-separator size_medium\"><\/div><div class=\"wpb_text_column us_custom_a574d586 has_text_color\"><div class=\"wpb_wrapper\"><h2><span style=\"font-weight: 400;\">From ground deformation to faulting<\/span><\/h2>\n<\/div><\/div><div class=\"wpb_text_column us_custom_760b8a55 has_text_color\"><div class=\"wpb_wrapper\"><p>Look at the effects, go back to the causes<\/p>\n<\/div><\/div><div class=\"w-separator size_large\"><\/div><\/div><\/div><\/div><\/div><\/section><section class=\"l-section wpb_row height_medium\"><div class=\"l-section-h i-cf\"><div class=\"g-cols vc_row via_grid cols_1-2-1 laptops-cols_inherit tablets-cols_inherit mobiles-cols_1 valign_top type_default stacking_default\"><div class=\"wpb_column vc_column_container\"><div class=\"vc_column-inner\"><\/div><\/div><div class=\"wpb_column vc_column_container\"><div class=\"vc_column-inner\"><div class=\"wpb_text_column\"><div class=\"wpb_wrapper\"><p><span style=\"font-weight: 400;\">To understand how the parameters of a fault that generated an earthquake are obtained from InSAR maps, we must preliminarily introduce the concept of model. A model is a tool that reproduces a real phenomenon for the purpose of studying and better understanding it. There are various types of models, but we can distinguish two broad categories: <strong>analog models<\/strong> and <strong>mathematical models<\/strong>. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">For example, to study the impact of earthquakes on a building, we can build a model of the structure and put it on a vibrating platform. It is, in this case, an analog model, which reproduces reality in a small scale. Alternatively, or in addition, we can use mathematical equations in which we put the parameters of the structure and calculate the stresses: we can check, for example, whether the stress to which a column is subjected by a possible earthquake exceeds that expected. This is evidently a mathematical model. <\/span><\/p>\n<p><span style=\"font-weight: 400;\">Mathematical models are widespread because they are powerful tools for the use of which all that is needed is a computer, at most very powerful, such as those used for weather forecasting.<\/span><\/p>\n<p><span style=\"font-weight: 400;\"><strong>For faults we use mathematical models<\/strong>, i.e., equations into which we put the fault parameters<em>(length<\/em>, <em>width<\/em>, <em>slope<\/em>, <em>extent and direction of sliding<\/em>, etc.) and obtain displacement maps.<img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-794\" src=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/forward_modeling_eng.jpeg\" alt=\"\" width=\"1571\" height=\"710\" srcset=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/forward_modeling_eng.jpeg 1571w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/forward_modeling_eng-300x136.jpeg 300w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/forward_modeling_eng-1024x463.jpeg 1024w\" sizes=\"auto, (max-width: 1571px) 100vw, 1571px\" \/><\/span><span style=\"font-weight: 400;\">This model is also called a <strong>direct model<\/strong>, because starting from the causes of an earthquake (the fault) it returns the effects (the displacements). Once the displacement maps are obtained, we can compare them with those measured by SAR satellites.<img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-796\" src=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/modeled_observed.jpeg\" alt=\"\" width=\"1247\" height=\"698\" srcset=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/modeled_observed.jpeg 1247w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/modeled_observed-300x168.jpeg 300w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/modeled_observed-1024x573.jpeg 1024w\" sizes=\"auto, (max-width: 1247px) 100vw, 1247px\" \/><\/span><span style=\"font-weight: 400;\">But here comes the problem: what fault parameters do we use to feed the model, if we do not know them? We are in the presence of what is called, in mathematics, an <strong>inverse problem<\/strong>: we see the effects of an earthquake (the deformations) and we want to infer the causes (the fault parameters). <\/span><\/p>\n<p><span style=\"font-weight: 400;\">One could go by trial and error: we change the fault parameters until we find the ones that produce the most similar displacements to those observed. This is a legitimate but impractical way: there can be hundreds of parameters, and finding the right <em>cocktail<\/em> is not easy. There are more refined tools called <strong>inversion algorithms<\/strong> that do just that job for us: <strong>finding the source parameters that generate surface deformations as similar as possible to those observed<\/strong>. <img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-792\" src=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/inversion_scheme.jpeg\" alt=\"\" width=\"1318\" height=\"1423\" srcset=\"https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/inversion_scheme.jpeg 1318w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/inversion_scheme-278x300.jpeg 278w, https:\/\/www.finitesource.com\/wp-content\/uploads\/2025\/11\/inversion_scheme-948x1024.jpeg 948w\" sizes=\"auto, (max-width: 1318px) 100vw, 1318px\" \/><\/span><span style=\"font-weight: 400;\">A good direct model and a robust inversion algorithm are the tools by which we find the faults published in this portal using satellite-derived data.<\/span><\/p>\n<\/div><\/div><\/div><\/div><div class=\"wpb_column vc_column_container\"><div class=\"vc_column-inner\"><\/div><\/div><\/div><\/div><\/section>\n","protected":false},"excerpt":{"rendered":"InsightsFrom ground deformation to faulting Look at the effects, go back to the causes To understand how the parameters of a fault that generated an earthquake are obtained from InSAR maps, we must preliminarily introduce the concept of model. A model is a tool that reproduces a real phenomenon for the purpose of studying and...","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[32],"tags":[],"class_list":["post-730","post","type-post","status-publish","format-standard","hentry","category-insights"],"_links":{"self":[{"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/posts\/730","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/comments?post=730"}],"version-history":[{"count":4,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/posts\/730\/revisions"}],"predecessor-version":[{"id":870,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/posts\/730\/revisions\/870"}],"wp:attachment":[{"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/media?parent=730"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/categories?post=730"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.finitesource.com\/en\/wp-json\/wp\/v2\/tags?post=730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}