Abstract
The Mauchline lavas of SW Scotland erupted close to the Carboniferous-Permian boundary and near the middle of the Permo-Carboniferous Reversed Superchron (PCRS). Rock magnetic studies have identified mixed magnetite-hematite assemblages; both minerals record reversed components of magnetisation. A fold test is not diagnostic but the mean remanence recovered in 23 stable samples at five sites ( D I = 192.5 −26.1 °, α 95 = 14.3°) accords with the regional field at the time of eruption and the pole position (346.8°E, 47.2°S) is coincident with late Carboniferous-Early Permian poles. A palaeointensity study of 15 samples employing the modified Thellier-Thellier method yields nine acceptable estimates of ancient field intensity with a mean value of 13.6 ± 4.5 μT from four lava flows. The corresponding virtual dipole moment of 3.3 × 10 22 Am 2 is approximately 40% of the present day value. This result supports recent studies from western Europe which suggest that the geomagnetic field strength was low during the PCRS but is in conflict with Russian data which suggest that the field strength was close to, or slightly higher than the present day value.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
