{"id":678,"date":"2023-08-08T11:47:16","date_gmt":"2023-08-08T15:47:16","guid":{"rendered":"https:\/\/wpstaging.whoi.edu\/site\/deeptow\/?page_id=678"},"modified":"2023-10-25T15:34:42","modified_gmt":"2023-10-25T19:34:42","slug":"jurassic-magnetism","status":"publish","type":"page","link":"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/","title":{"rendered":"Jurassic Magnetism"},"content":{"rendered":"\n\n\t<h1>Jurassic Magnetism &#8211; Near-bottom magnetic record<\/h1>\n<p>Jurassic-aged ocean crust represents the oldest surviving ocean crust in the world today and consequently only resides in a few places, such as along the continental margins of the Atlantic Ocean and in the western Pacific Ocean. This Jurassic crust is marked by the disappearance of correlatable magnetic anomaly stripes in both the Atlantic and Pacific oceans, thus leading to name of the &#8220;Jurassic Quiet Zone&#8221; or JQZ\u00a0<i>[Larson and Chase, 1972; Larson and Hilde, 1975; Cande et al, 1978; Vogt and Einwich, 1979]<\/i>. The precise origin of the JQZ is unclear. It could be period of constant polarity similar to the more well-known the Cretaceous Quiet Zone. It could be that the crust has suffered sufficient aging that the signal has been totally degraded. The equatorial latitude of the Pacific JQZ and deep water depths has meant that sea surface magnetic profiles are contaminated by noise from the strong diurnal and magnetic effects of the equatorial electrojet, so even measuring the magnetic field in these areas is difficult.<\/p>\n<p>I was Co-Principal Investigator with Paul Johnson (U Washington) and Will Sager (TAMU) on a 1992 deeptowed-magnetic survey of the JQZ in the western Pacific. This survey found correlatable magnetic lineations within the Jurassic Quiet Zone proving that the field was reversing quite fast (8-10 revs\/million years) during this period. A paper was been published in\u00a0<i>Journal of Geophysical Research, 1998<\/i>\u00a0on the results of this study.<\/p>\n<p>I was Co-Chief Scientist on RV Thompson (TN152) with Will Sager again in 2002\/2003 when we revisited the area using the deeptow-towed\u00a0<a href=\"https:\/\/www.whoi.edu\/what-we-do\/explore\/underwater-vehicles\/towed-vehicles\/dsl-120a\/\">DSL-120 sidescan sonar<\/a>\u00a0and magnetometer to extend the high-resolution survey south to ODP Hole 801C and also complete a detailed survey around the hole. Several papers have been published on those results (Tivey et al., 2006; Tominaga et al., 2008); see links to them below.<\/p>\n<ul>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-high-resolution-surveys-2002-2003-cruise\/\">Click here to go to JQZ2002 research page.<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/JQZ2002_report_complete-2.pdf\">Click here for the JQZ2002\/03 TN152 cruise report.<\/a><\/li>\n<\/ul>\n<p>In 2011, I was a Co-Principal Investigator again, this time with\u00a0<a href=\"https:\/\/www.msu.edu\/~tominaga\/index.html\">Masako Tominaga (Mich. State Univ)<\/a>\u00a0on a deeptow and autonomous underwater vehicle\u00a0<a href=\"https:\/\/www.whoi.edu\/what-we-do\/explore\/underwater-vehicles\/auvs\/sentry\/\">(Sentry)<\/a>\u00a0survey of the Pacific Hawaiian magnetic record. As part of this RV Thompson (TN272) marine survey we had a significant outreach component with\u00a0Prof. Adrienne Oakley of Kutztown University\u00a0who brought undergraduates out on the research vessel with an innovative outreach program.<\/p>\n<ul>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-high-resolution-surveys-2011-cruise\/\">Click here to go to JQZ2011 research page.<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/TN272_Cruise_Report-1.pdf\">Click here for the JQZ2011 cruise report.<\/a><\/li>\n<\/ul>\n<p>Most recently I completed a 2014\/2015 cruise onboard the newly launched icebreaker\u00a0RV Sikuliaq\u00a0where we took the ship to the tropical Pacific to complete the transect we started in 2011 on the Hawaiian lineations. This cruise with CoPIs Masako Tominaga (TAMU) and Will Sager (Houston) successfully completed seven long\u00a0<a href=\"https:\/\/www.whoi.edu\/what-we-do\/explore\/underwater-vehicles\/auvs\/sentry\/\">AUV Sentry<\/a>\u00a0dives along the transect corridor along with deeptow and sea surface towed magnetic profiles.<\/p>\n<ul>\n<li><a href=\"http:\/\/web.whoi.edu\/jurassicmagnetism\/welcome-to-the-jurassic-quiet-zone\">Click here for a link to the 2014 outreach website.<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-high-resolution-surveys-2014-cruise\/\">Click here to go to JQZ2014 research page.<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/skq201402s_cruisereport_final-2.pdf\">Click here for the JQZ2014 cruise report.<\/a><\/li>\n<\/ul>\n\t<h2>Data Links<\/h2>\n<p>Historical JQZ cruise data from 1992 (and soon 2002\/2003 cruise) will be available from the\u00a0IEDA-MGDS database.\u00a0This was part of a small data rescue project to Maurice Tivey made possible by\u00a0IEDA.<\/p>\n\t<h2>Links to published papers<\/h2>\n<ul>\n<li>Sager, Weiss,\u00a0<strong><u>Tivey<\/u><\/strong>, and Johnson, 1998:\u00a0<a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/sager1998.pdf\"><strong>Geomagnetic polarity reversal model of deep-tow profiles from the Pacific Jurassic Quiet Zone.<\/strong><\/a><strong>\u00a0\u00a0<\/strong><em>J. Geophys. Res.<\/em><\/li>\n<li><strong><u>Tivey<\/u><\/strong>, Larson, Schouten and Pockalny, 2005:\u00a0<a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/tivey2005.pdf\"><strong>Downhole magnetic measurements of ODP Hole 801C: Implications for Pacific oceanic crust and magnetic field behavior in the Middle Jurassic.<\/strong><\/a><strong>\u00a0<\/strong><em>Geochem. Geophys. Geosys.<\/em><\/li>\n<li><strong><u>Tivey<\/u><\/strong>, Sager, Lee and Tominaga, 2006:\u00a0<a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/tivey2006.pdf\"><strong>Origin of the Pacific Jurassic Quiet Zone.<\/strong>\u00a0<\/a><strong>\u00a0<\/strong><em>Geology<\/em><\/li>\n<li>Tominaga, Sager,\u00a0<strong><u>Tivey<\/u><\/strong>\u00a0and Lee, 2008:\u00a0<a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/tominaga_etal_JGR08.pdf\"><strong>Deep-tow magnetic anomaly study of the Pacific Jurassic Quiet Zone and implications for the geomagnetic polarity reversal timescale and geomagnetic field behavior.<\/strong>\u00a0<\/a><strong>\u00a0<\/strong><em>J. Geophys. Res.<\/em><\/li>\n<li>Tominaga and Sager, 2010:\u00a0Revised Pacific M-anomaly geomagnetic polarity Time scale\u00a0<em>Geophys. J. Int.<\/em><\/li>\n<li>Tominaga,\u00a0<strong><u>Tivey<\/u><\/strong>, and Sager, 2015:\u00a0<a href=\"https:\/\/website.whoi.edu\/deeptow\/wp-content\/uploads\/sites\/66\/2023\/08\/TominagaTiveySager2015.pdf\"><strong>Nature of the Jurassic Magnetic Quiet Zone.<\/strong><\/a><strong>\u00a0<\/strong><em>Geophys. Res. Lett.<\/em><\/li>\n<li>Tominaga,\u00a0<strong><u>Tivey<\/u><\/strong>, and Sager, 2121:\u00a0A New Middle to Late Jurassic Geomagnetic Polarity Time Scale (GPTS) from a multiscale marine magnetic anomaly survey of the Pacific Jurassic Quiet Zone.<strong>\u00a0<\/strong><em>Jour. Geophys. Res.<\/em><\/li>\n<\/ul>\n\t<ul>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-1992-survey\/\">Click here to go to the results from the 1992 survey.<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-high-resolution-surveys-2011-cruise\/\">Link to the 2011 page documenting the survey of the Jurassic Pacific Hawaiian lineations<\/a><\/li>\n<li><a href=\"https:\/\/website.whoi.edu\/deeptow\/research\/jurassic-magnetism\/jurassic-magnetism-high-resolution-surveys-2014-cruise\/\">Link to the 2014 page documenting the AUV survey of the Jurassic Pacific Hawaiian lineations<\/a><\/li>\n<\/ul>\n\n","protected":false},"excerpt":{"rendered":"<p>Jurassic Magnetism &#8211; Near-bottom magnetic record Jurassic-aged ocean crust represents the oldest surviving ocean crust in the world today and consequently only resides in a few places, such as along the continental margins of the Atlantic Ocean and in the western Pacific Ocean. This Jurassic crust is marked by the disappearance of correlatable magnetic anomaly&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":588,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":""},"_links":{"self":[{"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/pages\/678"}],"collection":[{"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/comments?post=678"}],"version-history":[{"count":3,"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/pages\/678\/revisions"}],"predecessor-version":[{"id":1084,"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/pages\/678\/revisions\/1084"}],"up":[{"embeddable":true,"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/pages\/588"}],"wp:attachment":[{"href":"https:\/\/website.whoi.edu\/deeptow\/wp-json\/wp\/v2\/media?parent=678"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}