[ { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fwbvj-tg482", "eprint_id": 79524, "eprint_status": "archive", "datestamp": "2023-08-19 05:53:11", "lastmod": "2023-10-26 16:16:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Grappone-J-M", "name": { "family": "Grappone", "given": "J. Michael" }, "orcid": "0000-0001-5004-8561" }, { "id": "Chaffee-Thom", "name": { "family": "Chaffee", "given": "Thom" } }, { "id": "Isozaki-Yukio", "name": { "family": "Isozaki", "given": "Yukio" } }, { "id": "Bauert-Heikki", "name": { "family": "Bauert", "given": "Heikki" } }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" } ] }, "title": "Investigating the duration and termination of the Early Paleozoic Moyero reversed polarity Superchron: Middle Ordovician paleomagnetism from Estonia", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Elsevier B.V. \n\nReceived 22 March 2017, Revised 23 July 2017, Accepted 24 July 2017, Available online 26 July 2017. \n\nWe thank Momoko Shimatsuka, Hiroki Nakahata, Tomoyo Tobita, Valerie Pietrasz and Isaac Hilburn for fieldwork assistance, technical help and support through the project. We would also like to thank and acknowledge the Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant-in-Aid, no. 26257212) for fieldwork expenses, the Summer Undergraduate Research Fellowship program at Caltech to Thomas Chaffee, and named SURF donors, Karen and James Cutts, for providing funding for part of this project.\n\n
Accepted Version - 1-s2.0-S0031018217302067-main.pdf
", "abstract": "Ever since their discovery nearly 50 years ago, geomagnetic superchrons have been a puzzle for the geophysical community. Although there have only been a few during Phanerozoic time, Driscoll and Evans (2016) recently proposed multiple superchrons during the Proterozoic. Biggin et al. (2012) suggested that superchrons are the result of low heat flow at the Core Mantle Boundary (CMB), which causes low dynamo activity, and that they are generally separated by 180\u2013190 Myr. According to Courtillot and Olson (2007), one potential process for ending a superchron is via the generation of a superplume at the bottom of the mantle, followed by the eruption of a large igneous province (LIP) 10\u201320 Myr later. However, this theory is unable to explain the Middle Cretaceous LIP activity and recent modelling favors a longer plume rise-time of 20\u201350 Myr (Biggin et al., 2012).", "date": "2017-11-01", "date_type": "published", "publication": "Palaeogeography, Palaeoclimatology, Palaeoecology", "volume": "485", "publisher": "Elsevier", "pagerange": "673-686", "id_number": "CaltechAUTHORS:20170728-073217224", "issn": "0031-0182", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170728-073217224", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Japan Society for the Promotion of Science (JSPS)", "grant_number": "26257212" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Karen and James Cutts" } ] }, "doi": "10.1016/j.palaeo.2017.07.024", "primary_object": { "basename": "1-s2.0-S0031018217302067-main.pdf", "url": "https://authors.library.caltech.edu/records/fwbvj-tg482/files/1-s2.0-S0031018217302067-main.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Grappone, J. Michael; Chaffee, Thom; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cgkyx-w6467", "eprint_id": 56120, "eprint_status": "archive", "datestamp": "2023-08-22 14:44:40", "lastmod": "2023-10-20 23:40:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" }, { "id": "Isozaki-Yukio", "name": { "family": "Isozaki", "given": "Yukio" } }, { "id": "Shibuya-Hideotoshi", "name": { "family": "Shibuya", "given": "Hideotoshi" } }, { "id": "Otofuji-Yo-ichiro", "name": { "family": "Otofuji", "given": "Yo-ichiro" } }, { "id": "Raub-T-D", "name": { "family": "Raub", "given": "Timothy D." }, "orcid": "0000-0002-7471-0246" }, { "id": "Hilburn-I-A", "name": { "family": "Hilburn", "given": "Isaac A." } }, { "id": "Kasuya-Teruhisa", "name": { "family": "Kasuya", "given": "Teruhisa" } }, { "id": "Yokoyama-Masahiko", "name": { "family": "Yokoyama", "given": "Masahiko" } }, { "id": "Bonifacie-M", "name": { "family": "Bonifacie", "given": "Magali" } } ] }, "title": "Challenging the sensitivity limits of Paleomagnetism:\n Magnetostratigraphy of weakly magnetized Guadalupian\u2013Lopingian (Permian) Limestone from Kyushu, Japan", "ispublished": "pub", "full_text_status": "public", "keywords": "Paleomagnetism; Limestone; Permian; Kiaman superchron; Illawarra Reversal; Mass extinction", "note": "\u00a9 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license. Received 5 July 2014, Revised 14 October 2014, Accepted 28 October 2014, Available online 4 November 2014.\n\nWe thank Tomomi Kani of Kumamoto University, Masafumi Saitoh, Tomohiko Sato, and Daisuke Kofukuda of the University of Tokyo (Komaba) for their help in field work, and John Eiler of the California Institute of Technology for use of mass spectrometer for clumped isotope measurements.\n\nPublished - 1-s2.0-S0031018214005537-main.pdf
Supplemental Material - mmc1.pdf
Supplemental Material - mmc2.xls
", "abstract": "Despite their utility for bio- and chemostratigraphy, many carbonate platform sequences have been difficult to analyze using paleomagnetic techniques due to their extraordinarily weak natural remanent magnetizations (NRMs). However, the physical processes of magnetization imply that stable NRMs can be preserved that are many orders of magnitude below our present measurement abilities. Recent advances in reducing the noise level of superconducting magnetometer systems, particularly the introduction of DC-SQUID sensors and development of a low-noise sample handling system using thin-walled quartz-glass vacuum tubes, have solved many of these instrumentation problems, increasing the effective sensitivity by a factor of nearly 50 over the previous techniques of SQUID moment magnetometry.\n\nHere we report the successful isolation of a two-polarity characteristic remanent magnetization from Middle\u2013Late Permian limestone formed in the atoll of a mid-oceanic paleo-seamount, now preserved in the Jurassic accretionary complex in Japan, which had proved difficult to analyze in past studies. Paleothermometric indicators including Conodont Alteration Indices, carbonate petrology, and clumped isotope paleothermometry are consistent with peak burial temperatures close to 130 \u00b0C, consistent with rock magnetic indicators suggesting fine-grained magnetite and hematite holds the NRM. The magnetic polarity pattern is in broad agreement with previous global magnetostratigraphic summaries from the interval of the Early\u2013Middle Permian Kiaman Reversed Superchron and the Permian\u2013Triassic mixed interval, and ties the Tethyan\u2013Panthalassan fusuline zones to it. Elevated levels of hematite associated with the positive \u03b4^(13)C_(carb) of the Kamura event argue for a brief spike in environmental oxygen. The results also place the paleo-seamount at a paleolatitude of ~ 12\u00b0 S, in the middle of the Panthalassan Ocean, and imply a N/NW transport toward the Asian margin of Pangea during Triassic and Jurassic times, in accordance with the predicted trajectory from its tectono-sedimentary background. These developments should expand the applicability of magnetostratigraphic techniques to many additional portions of the Geological time scale.", "date": "2015-01-15", "date_type": "published", "publication": "Palaeogeography, Palaeoclimatology, Palaeoecology", "volume": "418", "publisher": "Elsevier", "pagerange": "75-89", "id_number": "CaltechAUTHORS:20150326-102243417", "issn": "0031-0182", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150326-102243417", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1016/j.palaeo.2014.10.037", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/cgkyx-w6467/files/mmc1.pdf" }, "related_objects": [ { "basename": "mmc2.xls", "url": "https://authors.library.caltech.edu/records/cgkyx-w6467/files/mmc2.xls" }, { "basename": "1-s2.0-S0031018214005537-main.pdf", "url": "https://authors.library.caltech.edu/records/cgkyx-w6467/files/1-s2.0-S0031018214005537-main.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Kirschvink, Joseph L.; Isozaki, Yukio; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rbn8a-xcv18", "eprint_id": 24614, "eprint_status": "archive", "datestamp": "2023-08-22 03:08:33", "lastmod": "2023-10-23 23:30:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sekine-Yasuhito", "name": { "family": "Sekine", "given": "Yasuhito" } }, { "id": "Tajika-Eiichi", "name": { "family": "Tajika", "given": "Eiichi" } }, { "id": "Tada-Ryuji", "name": { "family": "Tada", "given": "Ryuji" } }, { "id": "Hirai-Takemaru", "name": { "family": "Hirai", "given": "Takemaru" } }, { "id": "Goto-Kosuke-T", "name": { "family": "Goto", "given": "Kosuke T." } }, { "id": "Kuwatani-Tatsu", "name": { "family": "Kuwatani", "given": "Tatsu" } }, { "id": "Goto-Kazuhisa", "name": { "family": "Goto", "given": "Kazuhisa" } }, { "id": "Yamamoto-Shinji", "name": { "family": "Yamamoto", "given": "Shinji" } }, { "id": "Tachibana-Shogo", "name": { "family": "Tachibana", "given": "Shogo" } }, { "id": "Isozaki-Yukio", "name": { "family": "Isozaki", "given": "Yukio" } }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" } ] }, "title": "Manganese enrichment in the Gowganda Formation of the Huronian Supergroup: A highly oxidizing shallow-marine environment after the last Huronian glaciation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "The Great Oxidation Event; Huronian Supergroup; Glaciation; Ocean redox state; Paleoproterozoic", "note": "\u00a9 2011 Elsevier B.V.\n\nReceived 14 February 2011; revised 27 April 2011; accepted 1 May 2011. Editor: P. DeMenocal. Available online 23 May 2011.\n\nThe authors thank M. Hailstone and A. Pace at the Ontario\nGeological Survey, Canada, for advice and access to their core library, without which this project could not have been done. This study is partly supported by Grant in Aid from the Japan Society for the Promotion of Science (No. 14403004 and No. 18340128), the 21 century COE Program at Dept. of Earth and Planetary Science, Univ. of\nTokyo, the Mitsubishi foundation, the NASA Exobiology program, and the Agouron Institute.", "abstract": "Oxidative precipitation and authigenic enrichment of the redox sensitive element Mn in sedimentary rocks can serve as a proxy for the release of high levels of O_2 during the Great Oxidization Event (GOE). Here we investigate Mn abundance in sedimentary rocks of the 2.45\u20132.22 Ga Huronian Supergroup, Canada. We found authigenic Mn enrichments with high Mn/Fe ratios following the appearance of Fe oxides in the Firstbrook Member of the Gowganda Formation of the Huronian Supergroup, which was deposited immediately after the last Huronian glaciation. The Mn-bearing minerals in the Firstbrook Member are spessartine-rich almandine and Mn-bearing chlorite, which are likely to have been formed through post-depositional diagenesis and/or metamorphism using Mn oxides precipitated in the ocean at the time of deposition. When assuming the solution equilibrium between the atmosphere and shallow oceans, oxidative Mn precipitation requires that atmospheric O_2 be higher than ~ 10^(\u22122) times the present atmospheric level (PAL). The cumulative Mn amount per unit area in the Firstbrook Member is comparable in magnitude to that in the Mn deposits in the Hotazel Formation of the Transvaal Supergroup, South Africa. Our results suggest an appearance of highly active aerobic biosphere immediately after the last Huronian glaciation, supporting the hypothesis that climatic recovery from the Huronian glaciation accelerated the GOE.", "date": "2011-07-01", "date_type": "published", "publication": "Earth and Planetary Science Letters", "volume": "307", "number": "1-2", "publisher": "Elsevier", "pagerange": "201-210", "id_number": "CaltechAUTHORS:20110801-113538061", "issn": "0012-821X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110801-113538061", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Japan Society for the Promotion of Science", "grant_number": "14403004" }, { "agency": "Japan Society for the Promotion of Science", "grant_number": "18340128" }, { "agency": "Univ. of Tokyo Dept. of Earth and Planetary Science, 21 century COE Program" }, { "agency": "Mitsubishi foundation" }, { "agency": "NASA Exobiology program" }, { "agency": "Agouron Institute" } ] }, "doi": "10.1016/j.epsl.2011.05.001", "resource_type": "article", "pub_year": "2011", "author_list": "Sekine, Yasuhito; Tajika, Eiichi; et el." } ]