New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield
Thellier paleointensity experiments are carried out on the Early Cretaceous Arapey Formation, which belongs to the Parana Magmatic Province (PMP) in northern Uruguay. Twenty‐seven samples out of 225 analyzed yield reliable absolute intensity determinations. For these samples the NRM fraction f used...
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| Format: | Article |
| Language: | English |
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Wiley
2008-11-01
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| Series: | Geochemistry, Geophysics, Geosystems |
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| Online Access: | https://doi.org/10.1029/2008GC002102 |
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| author | Avto Goguitchaichvili Ruben Cejudo Ruiz Leda Sanchez Bettucci Bertha Aguilar Reyes Luis M. Alva‐Valdivia Jaime Urrutia‐Fucugauchi Juan Morales Manuel Calvo Rathert |
| author_facet | Avto Goguitchaichvili Ruben Cejudo Ruiz Leda Sanchez Bettucci Bertha Aguilar Reyes Luis M. Alva‐Valdivia Jaime Urrutia‐Fucugauchi Juan Morales Manuel Calvo Rathert |
| author_sort | Avto Goguitchaichvili |
| collection | DOAJ |
| description | Thellier paleointensity experiments are carried out on the Early Cretaceous Arapey Formation, which belongs to the Parana Magmatic Province (PMP) in northern Uruguay. Twenty‐seven samples out of 225 analyzed yield reliable absolute intensity determinations. For these samples the NRM fraction f used for determination ranges between 0.33 to 0.83 and the quality factor q ranges from 4.5 to 14.1, being generally greater than 5. The flow‐mean paleointensity values obtained in this study range from 16.3 ± 2.3 to 41.5 ± 3.8 μT, with corresponding virtual dipole moments (VDMs) from 3.4 ± 0.6 to 8.2 ± 0.8 (1022 Am2). This corresponds to mean VDM value of 6.4 ± 2.3 × 1022 Am2. 40Ar/39Ar dating on the PMP sequence by Feraud et al. (1999) gave a mean age of 132.2 ± 0.5 Ma. Our results in conjunction with previous studies (Kosterov et al., 1998; Goguitchaichvili et al., 2002) suggest that the paleostrength during the early Cretaceous might be as variable and strong as Brunhes data and not anomalously low as previously suggested. The scatter observed in our study is similar to recent findings by Granot et al. (2007) for the Troodos Ophiolite. |
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| institution | Directory Open Access Journal |
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| language | English |
| last_indexed | 2024-04-24T22:40:23Z |
| publishDate | 2008-11-01 |
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| series | Geochemistry, Geophysics, Geosystems |
| spelling | doaj.art-54d715e85bc043108e8b2bca7288375d2024-03-19T04:50:49ZengWileyGeochemistry, Geophysics, Geosystems1525-20272008-11-01911n/an/a10.1029/2008GC002102New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofieldAvto Goguitchaichvili0Ruben Cejudo Ruiz1Leda Sanchez Bettucci2Bertha Aguilar Reyes3Luis M. Alva‐Valdivia4Jaime Urrutia‐Fucugauchi5Juan Morales6Manuel Calvo Rathert7Laboratorio Interinstitucional de Magnetismo Natural, Instituto de Geofísica–Sede Michoacán Universidad Nacional Autónoma de México Campus Morelia, C. P. 58089 Michoacán MéxicoLaboratorio Interinstitucional de Magnetismo Natural, Instituto de Geofísica–Sede Michoacán Universidad Nacional Autónoma de México Campus Morelia, C. P. 58089 Michoacán MéxicoDepartamento de Geología, Área Geofísica‐Geotectónica, Facultad de Ciencias Universidad de la República 11200 Montevideo UruguayLaboratorio Interinstitucional de Magnetismo Natural, Instituto de Geofísica–Sede Michoacán Universidad Nacional Autónoma de México Campus Morelia, C. P. 58089 Michoacán MéxicoLaboratorio de Paleomagnetismo y Paleoambientes, Instituto de Geofísica Universidad Nacional Autónoma de México Ciudad Universitaria S/N, 04510 México, D.F. MéxicoLaboratorio de Paleomagnetismo y Paleoambientes, Instituto de Geofísica Universidad Nacional Autónoma de México Ciudad Universitaria S/N, 04510 México, D.F. MéxicoLaboratorio Interinstitucional de Magnetismo Natural, Instituto de Geofísica–Sede Michoacán Universidad Nacional Autónoma de México Campus Morelia, C. P. 58089 Michoacán MéxicoDepartamento de Física, Escuela Politécnica Superior Universidad de Burgos E‐09001 Burgos SpainThellier paleointensity experiments are carried out on the Early Cretaceous Arapey Formation, which belongs to the Parana Magmatic Province (PMP) in northern Uruguay. Twenty‐seven samples out of 225 analyzed yield reliable absolute intensity determinations. For these samples the NRM fraction f used for determination ranges between 0.33 to 0.83 and the quality factor q ranges from 4.5 to 14.1, being generally greater than 5. The flow‐mean paleointensity values obtained in this study range from 16.3 ± 2.3 to 41.5 ± 3.8 μT, with corresponding virtual dipole moments (VDMs) from 3.4 ± 0.6 to 8.2 ± 0.8 (1022 Am2). This corresponds to mean VDM value of 6.4 ± 2.3 × 1022 Am2. 40Ar/39Ar dating on the PMP sequence by Feraud et al. (1999) gave a mean age of 132.2 ± 0.5 Ma. Our results in conjunction with previous studies (Kosterov et al., 1998; Goguitchaichvili et al., 2002) suggest that the paleostrength during the early Cretaceous might be as variable and strong as Brunhes data and not anomalously low as previously suggested. The scatter observed in our study is similar to recent findings by Granot et al. (2007) for the Troodos Ophiolite.https://doi.org/10.1029/2008GC002102paleointensityCretaceousParaná Flood BasaltsArapey FormationUruguay |
| spellingShingle | Avto Goguitchaichvili Ruben Cejudo Ruiz Leda Sanchez Bettucci Bertha Aguilar Reyes Luis M. Alva‐Valdivia Jaime Urrutia‐Fucugauchi Juan Morales Manuel Calvo Rathert New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield Geochemistry, Geophysics, Geosystems paleointensity Cretaceous Paraná Flood Basalts Arapey Formation Uruguay |
| title | New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield |
| title_full | New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield |
| title_fullStr | New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield |
| title_full_unstemmed | New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield |
| title_short | New absolute paleointensity results from the Parana Magmatic Province (Uruguay) and the Early Cretaceous geomagnetic paleofield |
| title_sort | new absolute paleointensity results from the parana magmatic province uruguay and the early cretaceous geomagnetic paleofield |
| topic | paleointensity Cretaceous Paraná Flood Basalts Arapey Formation Uruguay |
| url | https://doi.org/10.1029/2008GC002102 |
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