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Abstract In small‐volume igneous intrusions, the duration of magmatism can be difficult to determine because assembly of an intrusion from component magma pulses may occur within geochronologic uncertainties. We demonstrate that the paleomagnetic record of short‐term movement of the geomagnetic pole (secular variation) can place constraints on the duration of intrusion assembly over shorter time periods. An analysis of14C data paired with paleomagnetic data from lava flows illustrates this approach. The flows record paleosecular variation that, when combined with the maximum rate of secular variation from the Holocene, returns a minimum time elapsed between any two flows. Data from an Oligocene laccolith indicate that this system records a minimum of 49° of secular variation and therefore took at least 750 years to be emplaced. High‐precision radiometric geochronology would be unable to resolve this assembly, suggesting that the paleosecular variation record in shallow igneous rocks contains valuable temporal constraints on upper crustal magmatism.
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ames v1.2.2 – Add get_doi and groups option to authors
This release included a groups option to the get_publisher, which returns the groups associated with a record. It also adds a get_doi function which returns the doi of a record.
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- Award ID(s):
- 2322420
- PAR ID:
- 10621415
- Publisher / Repository:
- CaltechDATA
- Date Published:
- Subject(s) / Keyword(s):
- GitHub IGA metadata Python software
- Format(s):
- Medium: X
- Right(s):
- License
- Sponsoring Org:
- National Science Foundation
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