Abstract
New Palaeomagnetic data for 30 sites (271 samples) and K–Ar data from five units in the Sierra de Las Cruces, western Basin of Mexico, provide constraints on the spatial-temporal evolution of arc magmatism in the central Trans-Mexican Volcanic Belt. The normal and reversed directions show a polarity pattern with a consistent spatial zonation perpendicular to the NNW–SSE trend of the range. The magnetostratigraphy and K–Ar dates indicate that volcanic activity in the Sierra de Las Cruces migrated southeastward at a mean rate of 1.6 cm/a, between 3.6 and 1.8 Ma, and that the rate of migration may have been higher, up to 4 cm/a, during the Gauss Chron. Normal and reversed directions pass the reversal test at a 95% confidence level. The mean Plio-Quaternary palaeomagnetic direction for Sierra de Las Cruces is D=350.7°, I=30.6° ( N=25, k=30.7, α 95=5.3°). The declination deviates to the west of the expected direction, which suggests that small counterclockwise rotations could take place during formation of the Sierra de Las Cruces volcanics.
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.
