RT Journal Article
T1 The Alhama de Murcia fault (SE Spain), a seismogenic fault in a diffuse plate boundary: Seismotectonic implications for the Ibero-Magrebian region
A1 Masana, Eulàlia
A1 Martínez Díaz, José Jesús
A1 Hernández Enrile, José Luis
A1 Santanach, Pere
AB The shortening between the African and the Iberian plates is absorbed by a number of faults distributed over a very wide zone with very low slip rates and long periods of seismic loading. Thus a seismotectonic map based only on faults associated with seismicity or with expressive geomorphic features is incomplete. It is possible to characterize seismogenic faults using paleoseismology. First, paleoseismological results based on trenching analysis in the eastern Betics (Lorca-Totana segment of the Alhama de Murcia fault are presented. The main paleoseismic parameters of this fault segment are (1) a minimum of two to three Mw 6.5-7 earthquakes in the last 27 kyr (shortly before 1650 A.D., between 830 and 2130 B.C. and shortly before 16.7 ka, respectively), with a mean recurrence period of 14 kyr, and a very short elapsed time, and (2) a net slip rate of 0.07-0.6 mm/yr during the last 30 kyr. These results were extrapolated to the rest of the known active faults in the eastern Betics and were added to the slip rates of the active faults at the African margin. The total slip rate of the transect, which crosses de Alhama de Murcia fault in Spain and reaches the Cheliff basin (Algeria), would represent 21-82% of the total shortening between Africa and Eurasia estimated from plate motion models and seismic moment summation. A number of factors could account for this discrepancy: (1) hidden seismogenic faults in the emerged areas, (2) absence of correlation between current and late Pleistocene slip rates, (3) extensive small faults that are undetected and that absorb a significant amount of the deformation, and (4) possible overestimation of the convergence rates.
PB American Geophysical Union Wiley
SN 2169-9313
YR 2004
FD 2004
LK https://hdl.handle.net/20.500.14352/128807
UL https://hdl.handle.net/20.500.14352/128807
LA eng
NO Masana, E., J. J. Martínez-Díaz, J. L. Hernández-Enrile, and P. Santanach (2004), The Alhama de Murcia fault (SE Spain), a seismogenic fault in a diffuse plate boundary: Seismotectonic implications for the Ibero-Magrebian region, J. Geophys. Res., 109, B01301, doi:10.1029/2002JB002359.
NO European Union
NO Comisión Interministerial de Ciencia y Tecnología (España)
DS Docta Complutense
RD 12 dic 2025