RT Journal Article
T1 Alkalic (ocean-island basalt type) and calc-alkalic volcanism in the Mexican volcanic belt: a case for plume-related magmatism and propagating rifting at an active margin?
A1 Márquez González, Álvaro
A1 Oyarzun Muñoz, Roberto
A1 Doblas Lavigne, Miguel Manuel Delas
A1 Verma, S.P.
AB The Mexican volcanic belt has been traditionally regarded as a classic case of subduction-related calc-alkalic volcanism. However, a series of geologic, geophysical, and petrological arguments makes this simple relationship doubtful. A seismic gap beneath the belt, a large-scale mantle anomaly, a graben triple-junction domain, and the presence of volumetrically important oceanic-island basalt (OIB) volcanism throughout the belt suggest a more complex tectonic scenario involving plume- and subduction-related processes. We here propose a model involving the development of a propagating rift opening from west to east in response to plume activity. The process started in Miocene time within the western sector of the belt (Guadalajara) and gave rise to a graben triple junction and OIB-type and calc-alkalic volcanism. Extension and volcanism proceeded to the east, giving rise to progressively younger ages for the initiation of OIB-type volcanism: (1) Miocene in the west (e.g., Guadalajara), (2) Pliocene in the central zone (e.g., Michoacán-Guanajuato), and (3) Quaternary farther east (e.g., Chichinautzin). Geochemical evidence suggests that part of the modern calc-alkalic volcanism (e.g., Chichinautzin) may be derived from magma mixing between the OIB mafic magmas and silicic, crust-derived magmas. However, we do not preclude some influence of the subducting slab in the generation of other (e.g., Jorullo) calc-alkalic volcanic rocks. Our model suggests a currently unrooted upper plume attached to the subcontinental lithosphere, which defines a hot zone beneath the Mexican volcanic belt.
PB Geological Society of America
SN 0091-7613
YR 1999
FD 1999-01
LK https://hdl.handle.net/20.500.14352/110528
UL https://hdl.handle.net/20.500.14352/110528
LA eng
NO Márquez, A. et al. (1999): «Alkalic (ocean-island basalt type) and calc-alkalic volcanism in the Mexican volcanic belt: A case for plume-related magmatism and propagating rifting at an active margin?», Geology, 27(1), pp. 51-54. Disponible en: https://doi.org/10.1130/0091-7613(1999)027<0051:AOIBTA>2.3.CO;2.
NO Universidad Complutense de Madrid
NO Universidad Nacional Autónoma de México
DS Docta Complutense
RD 8 abr 2025