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La Falla de Alhama de Murcia (FAM) es una falla de desgarre sinestral y cierta componente inversa, que fue la responsable del terremoto más catastrófico producido en España en los últimos 50 años, el terremoto de Lorca de 2011 (Mw 5.2). En este trabajo se presenta el estudio de dos trincheras paleosísmicas excavadas en la superficie del abanico aluvial de La Salud que se encuentra cubriendo la traza de la FAM en el sector oriental del segmento Lorca-Totana. La excavación de las trincheras se apoya en la realización de una prospección geofísica mediante tomografía eléctrica y perfiles GPR con el objetivo de obtener nuevos datos de recurrencia sísmica en esta zona de la falla. Tanto las trincheras como los datos geofísicos son coherentes con la existencia de un plano de falla buzando 30º hacia el sur que deforma visiblemente los últimos depósitos del abanico. Las trincheras nos indican la ocurrencia de entre 3 y 6 eventos paleosísmicos de ruptura superficial en los últimos 31 ky.

The differential stress that caused the extensional ductile shear o f Santa Ma de la Alameda during the collapse of the Variscan orogen in the Sistema Central (central Iberia) has been estimated using the dynamically recrystallized grain size of quartz. An estimate of the strain rate has been calculated by the flow laws for ductile strain of quartz knowing the deformation temperature. The stress history obtained for this shear band features 3 stages of 22-31 MPa, 34-65 MPa and 53-67 MPa. The increase o f the differential stress is caused by the concentration of the strain in smaller bands during mylonitization. The first stage can be correlated to the initial deformation of a wide shear band, the second stage can be related to the formation of two main mylonitic shears, and finally the third stage correspond to the deformation of thin (

The vertical component of the movement associated to a fault system striking NE-SW has been determine using geomorphic and structural observations. These faults are located in the Iberian Massif in the Lugo region. The results of both kind o f observations have coincided in characterising these faults as hinge and pivotal faults. Moreover, considering the different periods of time recorded by these methods, we can establish that these faults are Tertiary and it is very difficult to explain a previous origin because of the structure complexity and the coincidence of the measures. In addition, and according to the results obtained from this area, we believe that the measures taken from the geomorphic markers, can be used alone as reliable indicators of the vertical component in this kind of faults, especially in areas where there are no others indicators.

The sinuosity of the Cuadalhorce River in the Malaga Basin is studied in this paper. The Malaga Basin is located in the Internal Zone of the Western Betic Chain, southern Spain. The river channel is divided into 5 reaches from the mouth, according to the strike variations of the valley. The sinuosity decreases dramatically in reach 2 in comparison to the sinuosity in reaches 5, 4, and 3. We interpret this lower sinuosity in reach 2 as a decrease in the slope of the valley. This fact is also observed in the longitudinal profile of the river channel along reach 2. We conclude that the anomalies observed in reach 2 are due to a gentle syncline related to the active anticline of Sierra de Cártama.

This work shows the results o f a gravimetric survey carried out in the Malaga Basin (sited on the Internal Zone o f the Western Betic Chain, southern Spain). Three anomalies maps are exposed and interpreted, focusing on neotectonic aspects. In order to avoid the influence of peridotitic bodies which outcrop in the studied area, and the southward thinning of the crust, a regional anomaly map has been processed and subtracted to the Bouguer anomaly. So, a residual anomaly map has been reached, where neotectonic interpretation has been done. The main tectonic feature evidenced by gravimetric data is the Albornoque Fault. It represents the southern boundary o f the Malaga Basin with a noticeable vertical component, according to its high gradient. By other hand, the fold o f Sierra de Cartama is marked by a maximum axis. This axis continues westward giving a duplicated depocenter of the basin. It is interpreted as a reverse fault, related in depth with the folding o f Sierra de Cartama, and which affects the basement o f the basin. According with the current stress field in the zone (NNW-SSE), the proposed structures imply the existence o f a compressive neotectonic activity, where the Albornoque fault is interpreted as a high angle reverse fault o f a reverse fault