Rock Magnetism and Paleomagnetism of Some North Pacific Deep-Sea Sediments

Abstract

Research Article| March 01, 1975 Rock Magnetism and Paleomagnetism of Some North Pacific Deep-Sea Sediments H. P. JOHNSON; H. P. JOHNSON 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 981952Present address: (Johnson) Cooperative Institute for Research in Environmental Sciences, Department of Geology, University of Colorado, Boulder, Colorado 80302; (Kinoshita) Meteorological College, Asahi-Cho, Kashiwa, Japan. Search for other works by this author on: GSW Google Scholar H. KINOSHITA; H. KINOSHITA 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 981952Present address: (Johnson) Cooperative Institute for Research in Environmental Sciences, Department of Geology, University of Colorado, Boulder, Colorado 80302; (Kinoshita) Meteorological College, Asahi-Cho, Kashiwa, Japan. Search for other works by this author on: GSW Google Scholar R. T. MERRILL R. T. MERRILL 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 98195 Search for other works by this author on: GSW Google Scholar Author and Article Information H. P. JOHNSON 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 981952Present address: (Johnson) Cooperative Institute for Research in Environmental Sciences, Department of Geology, University of Colorado, Boulder, Colorado 80302; (Kinoshita) Meteorological College, Asahi-Cho, Kashiwa, Japan. H. KINOSHITA 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 981952Present address: (Johnson) Cooperative Institute for Research in Environmental Sciences, Department of Geology, University of Colorado, Boulder, Colorado 80302; (Kinoshita) Meteorological College, Asahi-Cho, Kashiwa, Japan. R. T. MERRILL 1Department of Oceanography and Geophysics Program, University of Washington, Seattle, Washington 98195 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1975) 86 (3): 412–420. https://doi.org/10.1130/0016-7606(1975)86<412:RMAPOS>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation H. P. JOHNSON, H. KINOSHITA, R. T. MERRILL; Rock Magnetism and Paleomagnetism of Some North Pacific Deep-Sea Sediments. GSA Bulletin 1975;; 86 (3): 412–420. doi: https://doi.org/10.1130/0016-7606(1975)86<412:RMAPOS>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Detailed paleomagnetic and rock magnetic studies have been conducted on eight deep-sea cores from the North Pacific. Magnetic studies include alternating field demagnetization, thermal demagnetization, anhysteretic remanent magnetization studies, magnetic hysteresis measurements over a variety of different temperatures, viscous and drying effects, strong field versus temperature measurements, x-ray diffraction, and x-ray fluorescence analyses. Six of the eight cores studied contain an abundance of fossils, particularly silicoflagellates, and appear to have acquired their remanent magnetization sufficiently close to the surface to reliably record the Earth's paleomagnetic field. The remaining two cores do not contain fossils and do not appear to accurately record the Earth's paleomagnetic field. Low-temperature oxidation appears to have occurred in situ in these cores. A gamma phase (cation-deficient spinel) iron-titanium oxide with lattice parameter of 8.38 A and Curie temperature of 545°C near the top of the cores changes with depth to a gamma phase with lattice parameter of 8.33 A and Curie temperature near 600°C close to the bottom of the cores. These chemical changes appear to be associated with the production of a chemical remanent magnetization that makes it impossible to use these cores for paleomagnetic studies. This work summarizes many of the problems in obtaining reliable paleomagnetic results from deep-sea cores, including possible spurious magnetic directions resulting from chemical changes, drying, and coring effects. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.