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SE Iberia Tectonics is presently dominated by the NNW-SSE convergence between the Eurasian and Nubian plates. Farther east, the eastern Spanish coast and the Valencia Trough are dominated by ENE-WSW extension related to thermal subsidence. This extension has been interpreted as the final stage of abort rift responsible for the ENE motion of the Balearic promontory. Our data from 11 CGNSS stations permit us to discuss the deformation partitioning in SE Iberia related to the two abovementioned processes.We identify three kinematic domains: a relatively stable domain, a domain moving towards NNW and undergoing NNW-SSE shortening, and a third domain relatively moving towards ENE and experiencing ENE-WSW extension. Our results indicate that plate convergence-related NNW-SSE shortening is mainly absorbed by the Eastern Betic Shear Zone (EBSZ), in agreement with previous studies, but also show that a significant fraction of this shortening is accommodated south of the EBSZ.We also identify and quantify for the first time ENE-WSW extension northeast of the EBSZ. We propose that this extension could be absorbed by basement normal faults whose surface expression is obscured due to decoupling of deformation between the basement and the cover. Our results shed light on the tectonic puzzle of SE Spain.

We here discuss the results of a local GNSS episodic network from the Baza sub-Basin (S Spain). This network including six sites, was established in 2008 and has been measured seven times since then. Our data permit us to present the first short-term slip rates for the two active faults in this area. The main active structure is the normal Baza Fault. We estimate slip rates for this fault ranging between 0.3±0.3 mm/yr and 1.3±0.4 mm/yr. For the strike-slip Galera Fault, we quantify the slip rate as 0.5±0.3 mm/yr. These values are higher than previously reported long-term slip rates. We postulate that the discrepancy for the Baza Fault between short-term and long-term slip rates could indicate that the fault is presently in a period with a displacement rate higher than the mean of the magnitude 6 seismic cycle. Moreover, the velocity vectors that we obtained also show the regional tectonic significance of the Baza Fault, as this structure accommodates one-third of the regional extension of the Central Betic Cordillera.Our results also show that the Baza and Galera Faults are kinematically coherent and they divide the Baza sub-Basin into two tectonic blocks. This points to a likely physical link between the Baza and Galera Faults; hence, a potential complex rupture involving both faults should be considered in future seismic hazard assessment studies.

This work was funded by the research project TASCUB (RTI2018- 100737-B-I00) of the Spanish Ministry of Science, Innovation and Universities, the research group VIGROB053 (University of Alicante), and the research group RNM 325 of the Junta de Andalucía. Iván Medina Cascales was funded by Ph.D. contract FPU16/00202 of the Spanish Ministry of Science, Innovation and Universities.Wewould like to thank the editor Martin Stokes, and the reviewers Francisco Moral, Pablo G. Silva, and the anonymous reviewer, whose useful comments and suggestions greatly improved the manuscript., In this work, we prove the usefulness of morphometric analyses, typically applied to basin-border faults, to define the tectonic geomorphology of a slow-moving, intrabasinal structure: the Galera Fault (Guadix-Baza Basin, southern Spain). The Galera Fault is a 30 km-long, oblique-slip fault with major left-lateral and minor vertical slip components. Through geological and structural analyses, we define for the first time the detailed surface geometry of the fault, which is characterized by features typical of left-lateral strike-slip faults. The morphometric analysis indicates that a combination of slow slip rates and the high erodibility of the juxtaposed basin infill deposits favours a rapid landscape response to fault activity that erases many landscape effects related to active tectonics. This masking is more effective on features generated by strike-slip displacement, leaving only subtle evidence, such as local stream deflections and upstream widening of catchments. In contrast, geomorphic effects related to vertical displacement are better preserved, including the control of the geometry of the main rivers and morphological differences in the drainage network between the two fault blocks. On the upthrown fault block, streams are generally shorter and steeper and have greater valley incision, leading to the development of a bad land landscape. Moreover, the vertical deformation of a Middle Pleistocene glacis surface (ca. 90 m) demonstrates the important role of this slow-moving intrabasinal fault in the generation of relief in the Betic Cordillera during recent Quaternary time. Although the impact of this fault on relief building is very low in comparison with oblique-slip, basin-border faults in the mountain range, it has a key control on the Quaternary landscape evolution., TASCUB (RTI2018- 100737-B-I00) of the Spanish Ministry of Science, Innovation and Universities, VIGROB053 (University of Alicante), RNM 325 of the Junta de Andalucía, FPU16/00202 of the Spanish Ministry of Science, Innovation and Universities

Successive excavation of 13 trenches of different orientations reveals the complexity of a normal fault zone in Pliocene-Pleistocene unconsolidated sediments on a strand of the Baza Fault, central Betic Cordillera, south Spain. These trenches and the excavation floor are interpreted and integrated to reconstruct the 3D geometry and internal architecture of the fault zone. The structure consists of two main fault strands: an eastern one with a few hundred metres throw and a western one with at least 15 m throw. These strands interact and gradually merge to the south, bounding a main deformation zone narrowing from ∼7 to 1 m along strike. Fault-bounded rock bodies, clay and sand smears, and clay injections define the structure. These features are highly variable in 3D. In the northern part of the outcrop, deformation is localized around the main strands, brittle in the west and more ductile to the east. As the strands and their fault zones increasingly interact, fault throw, rock deformation and maturity of the structure increase. Mechanical stratigraphy also controls the style of deformation. A realistic representation of this 4D picture of fault deformation is critical for modelling fluid flow in shallow to possibly deep, faulted sedimentary reservoirs. This research was founded by research group VIGROB053 (University of Alicante).

One of the most significant parameters for seismic hazard assessment analyses is the fault slip rate. The combination of both geological (long-term) and geodetic (short-term) data offers a more complete characterization of the seismic potential of active faults. Moreover, geodetic data are also a helpful tool for the analysis of geodynamic processes. In this work, we present the results of a local GPS network from the Baza sub-Basin (SE Spain). This network, which includes six sites, was established in 2008 and has been observed for seven years. For the first time, we obtain short-term slip rates for the two active faults in this area. For the normal Baza Fault, we estimate slip rates ranging between 0.3 ± 0.3 mm/yr and 1.3 ± 0.4 mm/yr. For the strike-slip Galera Fault, we quantify the slip rate as 0.5 ± 0.3 mm/yr. Our GPS study shows a discrepancy for the Baza Fault between the short-term slip rates and previously reported long-term rates. This discrepancy indicates that the fault could be presently in a period with a displacement rate higher than the mean of the magnitude 6 seismic cycle. Moreover, the velocity vectors that we obtained also show the regional tectonic significance of the Baza Fault, as this structure accommodates one-third of the regional extension of the Central Betic Cordillera. Our GPS-related slip rates form the basis for future seismic hazard analysis in this area. Our results have further implications, as they indicate that the Baza and Galera Faults are kinematically coherent and they divide the Baza sub-Basin into two tectonic blocks. This points to a likely physical link between the Baza and Galera Faults; hence, a potential complex rupture involving both faults should be considered in future seismic hazard assessment studies., We acknowledge the comments of Editor Prof. Irina M. Artemieva and two anonymous reviewers, which significantly improved the quality of this paper. This research was funded by the Spanish Ministry of Science, Innovation and University (Research Projects: RTI2018-100737-BI00 and CGL2016-80687-R), the University of Alicante (Research Project: VIGROB053), the University of Jaén (PAIUJA 2019-2020 and Programa Operativo FEDER Andalucía 2014-2020 - call made by UJA 2018), the University of Granada (B-RNM-301-UGR18) and the Junta de Andalucía regional government (RNM148, RNM282, and RNM370 and P18-RT-3275 research groups). We thank all observers who collected the data of survey-mode GPS measurements.

The Betic Cordillera (S Spain), located in the convergent plate boundary between Eurasia and Nubia, is an area of moderate seismicity. These plates converge at a rate of approximately 4 to 6 mm/yr in the NW-SE direction (see review by Nocquet, 2012). Between 2.7 to 3.9 mm/yr of present-day plate convergence is accommodated in N Africa. Active shortening must occur at rates ranging from 1.6 to 2.7±0.6 mm/year across the Algero-Balearic Basin and the SE Iberian Peninsula (Serpelloni et al., 2007; Pérez-Peña et al., 2010; Echeverría et al., 2013). In the Betic Cordillera, most of the deformation is concentrated in the Betic Internal Zones, while the Betic External zones are considered as a slow-strain area.In SE of Spain onshore active deformation and seismicity are mainly located along the Eastern Betic Shear Zone (EBSZ), a major strike-slip tectonic corridor belonging to the Betic Internal Zones. Regional and local geodetic studies indicate that the EBSZ is absorbing between 0.2 and 1.3 mm/yr (Serpelloni et al., 2007; Pérez-Peña et al., 2010; Echeverría et al., 2013; Borque et al., 2019), i.e. only a portion of regional deformation. We postulate that part of this deformation not absorbed by the EBSZ is accommodated in the eastern Betic External Zones, located to the north of the EBSZ, where several major historical earthquakes occurred (e.g., the 1748 Estubeny, 1396 Tavernes, and 2017 Caudete earthquakes). These major events have been attributed to the Jumilla Fault, the only major active structure described in this area (Giner-Robles et al. 2014; García-Mayordomo, J. and Jiménez-Díaz, A., 2015).We present new CGPS data analysis that corroborate that the eastern Betic External Zones accommodate a significant part of the present convergence. Furthermore, our preliminary data quantify deformation in this area for the first time, as we obtain a shortening rate in the N-S direction of 1.43±0.06 mm/yr in the western sector of the Jumilla Fault (Murcia sector) and of 1.69±0.07 mm/yr in the eastern sector of the fault (Valencia sector). We propose that this deformation is likely related to the Jumilla Fault. Our study place constraints on the seismic potential of the highly populated eastern Betic External Zones, as the preliminary values that we obtained are significantly higher than those previously stated. Consequently, we propose that a re-assesment of seismic hazard is necessary for this highly populated region. Moreover, we also propose a regional geodynamic model that provide insights into mechanisms controlling earthquakes in the eastern Betic External Zones. ReferencesBorque et al. (2019). Tectonics, 38, 5, 1824-1839Echeverria et al. (2013). Tectonophysics, 608, 600-612.Giner-Robles et al. (2014). Resúmenes de la 2ª Reunión Ibérica sobre Fallas Activas y Paleosismología, Lorca, España, 155-158.García-Mayordomo, J. and Jiménez-Díaz, A. (2015). In: Quaternary Faults Database of Iberia v.3.0 - November 2015 (García-Mayordomo et al., eds.), IGME, Madrid.Nocquet, J.M. (2012). Tectonophysics, 579, 220-242.Pérez-Peña et al. (2010). Geomorphology, 119, 74-87Serpelloni et al. (2007). Geophysical Journal Internationl, 169(3), 1180-1200.

The geometry and kinematics of active faults have a significant impact on their seismic potential. In this work, a structural characterization of the active Baza Fault (central Betic Cordillera, southern Spain) combining surface and subsurface data is presented. Two sectors are defined based on their surface geometry: a northern sector striking N–S to NNW–SSE with a narrow damage zone and a southern sector striking NW–SE with a wide damage zone. A kinematic analysis shows pure normal fault kinematics along most of the fault. Geometric differences between the northern and southern sectors are caused by i) a heterogeneous basement controlling the fault geometry at depth and in the cover; ii) different orientations of the Baza Fault in the basement with respect to the regional extension direction and iii) interaction with other active faults. We use this structural characterization to analyse the segmentation of the Baza Fault. According to segmentation criteria, the entire Baza Fault should be considered a single fault seismogenic segment. Consequently, the seismic potential of the fault is defined for a complete rupture. Magnitude for the Mmax event is calculated using several scale relationships, obtaining values ranging between Mw 6.6 and Mw 7.1. Recurrence times range between approximately 2,000 and 2,200 years for Mmax events and between 5,300 and 5,400 years for palaeo-events. A geodetic scenario modelled for an Mmax event of Mw 6.7 shows permanent vertical displacements of more than 0.40m and an overall WSW–ENE extension during entire ruptures of the Baza Fault. This work was funded by the research project TASCUB (RTI2018-100737-B-I00) of the Spanish Ministry of Science, Innovation and Universities, the research group VIGROB053 (University of Alicante), the research project AICO/2019/040 of the Generalitat Valenciana (Valencia regional government), and the research group RNM-325 of the Junta de Andalucía (Andalucia regional government). Iván Medina Cascales was funded by Ph.D. contract FPU16/00202 of the Spanish Ministry of Science, Innovation and Universities. Research partially funded by the Programa Operativo FEDER Andalucía 2014-2020-call made by the University of Jaén 2018.

The historical quarry of the Nueva Tabarca fortress (Mediterranean Sea, SE of Spain) was developed in a complex sedimentary Miocene deposit. Five lithostratigraphic units have been defined, including different lithologies such as breccias and microconglomerates (Unit 1), massive and laminated lithoarenites (Units 1, 3 and 5), calcarenites and biocalcirudites (Units 2 and 4). A complete stratigraphic description of this sequence has been carried out, as well as the petrophysical characterization of the most significant lithologies including the analysis of rock durability as well as hydraulic and mechanical properties. Regarding durability, the softest rocks correspond to those from the Unit 4, whilst samples from Units 2 and 5 are the most durable. Three weathering patterns were observed during the artificial ageing test according to both the velocity and intensity of the sample decay. Each pattern is explained according to water-circulation possibility through the rock, its porous system, and the mechanical strength. Rock weathering in monuments of Nueva Tabarca is quantified and discussed according to the results found in the laboratory. Several decay forms are observed in the building stones (mainly differential erosion, alveolization, and rounding forms). Both 3D photogrammetric and 3D geological model of the historical quarry were elaborated in order to quantify the extracted volume of building stones, differentiating the specific quarried percentage of each lithology. Correlation between the results obtained in the volumetric analysis of the historical quarry and the building stones used in the monuments has been carried out. 3D models were also used for determining the remaining rock volume in the current outcrops. Finally, a set of recommendations for future conservation works of the architectural heritage are proposed after the current availability of the different rock varieties and their petrophysical behaviour., Departamento de Ciencias de la Tierra y del Medio Ambiente, Universidad de Alicante, España, Instituto Geológico y Minero de España, España

This work presents the singular case of Nueva Tabarca island (SE Spain), which is an excellent example where stone-built monuments and historical quarries greatly enhance the geoheritage interest of this site. This small western Mediterranean island brings together a rich, diverse geological record and a baroque architectural heritage represented by a fortified village. The geoheritage constitutes the bedrock of the historical and architectural monuments. In addition, though, the building stones can be used to interpret the litho- and bio-facies, which provide significant geological knowledge to better understand the island’s geosedimentary history. Furthermore, the diverse settings of the building stones allow a didactic and integrated reading of the erosional processes that can affect these stones. In short, architectural heritage becomes an alternative tool to study geology and promote geoheritage. The characterization and inventory of the local geoheritage has allowed us to propose a geotourism route of ten sites of special interest. The sites were selected due to their relevance showing the geological context, the building stones used in the architectural heritage, and the conservation state and the weathering processes that affect rocks. This paper evidences that geosites can be of special significance, particularly in geotourism, precisely due to their huge potential to connect heritages of varied natures. The closer the links between geology, history, and architecture, the more people will be interested in and concerned about geoheritage. This research was supported by projects GRE12-03, GRE14-05 (University of Alicante) and GV/2018//109 (Generalitat Valenciana).

This paper on the Baza Fault provides the first palaeoseismic data from trenches in the central sector of the Betic Cordillera (S Spain), one of the most tectonically active areas of the Iberian Peninsula. With the palaeoseismological data we constructed time-stratigraphic OxCal models that yield probability density functions (PDFs) of individual palaeoseismic event timing. We analysed PDF overlap to quantitatively correlate the walls and site events into a single earthquake chronology. We assembled a surface-rupturing history of the Baza Fault for the last ca. 45,000 years. We postulated six alternative surface rupturing histories including 8–9 fault-wide earthquakes. We calculated fault-wide earthquake recurrence intervals using Monte Carlo. This analysis yielded a 4750–5150 yr recurrence interval. Finally, compared our results with the results from empirical relationships. Our results will provide a basis for future analyses of more of other active normal faults in this region. Moreover, our results will be essential for improving earthquake-probability assessments in Spain, where palaeoseismic data are scarce. This research was founded by the Spanish Ministry of Economics, Industry and Competitiveness (MINECO) research Projects CGL2011-30153-C02-02 and EPILATES (CGL2015-65602-R). Also by the research group VIGROB053 (University of Alicante), the research Project UJA2014/06/17 (Caja Rural de Jaén and University of Jaen) and the research contract 2015CL015 (University of Jaen).

This work presents a 3D geometric model of growth strata cropping out in a fault-propagation fold associated with the Crevillente Fault (Abanilla-Alicante sector) from the Bajo Segura Basin (eastern Betic Cordillera, southern Spain). The analysis of this 3D model enables us to unravel the along-strike and along-section variations of the growth strata, providing constraints to assess the fold development, and hence, the fault kinematic evolution in space and time. We postulate that the observed along-strike dip variations are related to lateral variation in fault displacement. Along-section variations of the progressive unconformity opening angles indicate greater fault slip in the upper Tortonian–Messinian time span; from the Messinian on, quantitative analysis of the unconformity indicate a constant or lower tectonic activity of the Crevillente Fault (Abanilla-Alicante sector); the minor abundance of striated pebbles in the Pliocene-Quaternary units could be interpreted as a decrease in the stress magnitude and consequently in the tectonic activity of the fault. At a regional scale, comparison of the growth successions cropping out in the northern and southern limits of the Bajo Segura Basin points to a southward migration of deformation in the basin. This means that the Bajo Segura Fault became active after the Crevillente Fault (Abanilla-Alicante sector), for which activity on the latter was probably decreasing according to our data. Consequently, we propose that the seismic hazard at the northern limit of the Bajo Segura Basin should be lower than at the southern limit. This study was supported by: Spanish Ministry of Economy and Competitiveness (Research Project: CGL2011-30153-C02-02), Alicante University (Research Project: VIGROB053).

The Agost Basin is characterized by a Miocene–Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E–W to N–S. The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages: (1) stepover/releasing bend with a dextral motion of blocks; (2) very close to pure horizontal compression; and (3) restraining bend with a sinistral movement of blocks. In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p. The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p.) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p.), the area was affected by sinistral restraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results, the Agost Basin can be considered a key case of the interference between salt tectonics and the evolution of strike-slip fault zones. The reconstructed model has been compared with several scaled sandbox analogical models and with some natural pull-apart basins. Research supported by: Research Project CGL2016-75679-P, Spanish Ministry of Education and Science; Research Groups and Projects of the Generalitat Valenciana, Alicante University (CTMA-IGA); Research Group RNM 146, Junta de Andalucía; Grants from University of Urbino “Carlo Bo”, responsible M. Tramontana.

Some Internal Units of the western Alpine peri-Mediterranean orogenic system (Betic Cordillera, Calabria-Peloritani Arc) point out to a complex Alpine tectono-metamorphic evolution followed by an exhumation phase. Before the onset of the Alpine compressive tectonics, the rocks of these units belonged to the margins of a microcontinent, the Mesomediterranean Microplate, originated, together with the main plates, following the break-up of Pangaea. To these units, characterized by similar tectono-sedimentary evolution, belongs the Ali-Montagnareale Unit of the Peloritani Mountains (NE Sicily), where the Internal Units of the Sicilian sector of the Maghrebian Chain crop out. The Ali-Montagnareale Unit appears within two small tectonic semi-windows, under the phyllites of the Mandanici-Piraino Unit, and it proves to be formed by three groups of anchimetamorphic formations.The Lower Group is made up of two Upper Permian?-Upper Triassic siliciclastic formations, which grade into each other and which were deposited in alluvial environments. This group is followed by the Intermediate Group, consisting of Middle?-Upper? Triassic formations, indicating deposition in an evaporitic coastal plain evolving to a marine carbonate platform. The Upper Group consists of a Pliensbachian formation, made up of pelagic calcilutites with added carbonate turbiditic beds, followed by a prevailingly marly formation with strata of silicified limestones and episodic calcareous re-sediments. In this latter formation, the finding of Jurassic fossils and Globuligerina oxfordiana, which occurs up to the Valanginian, indicate that the stratigraphic succession spans from the late Early Jurassic to the Late Jurassic and probably reaches the Early Cretaceous.The stratigraphic units are generally separated by tectonic contacts which act as preferential detachment surfaces during compressive and exhumation tectonic phases. The tectonic elision of more or less large intervals of the original stratigraphic succession is diffuse in both tectonic windows.The succession of the Ali-Montagnareale Unit testifies to extensional tectonics, which in Middle-Late Triassic determined the evolution of sedimentation from continental to evaporitic and neritic environments, and, since the Early Jurassic, to calcilutite and marly pelagic sediments with added calcareous re-sediments. This sedimentary evolution records the break-up of Pangaea and the successive opening of oceanic basins. A similar tectono-sedimentary history may be recognized in many other Internal Units of the Alpine peri-Mediterranean Chains.

A litho-biostratigraphic analysis has been carried out in the Gador-Turon unit of the Sierra de Gador (Alpujarride complex, Betic Cordillera, SE Spain). The Triassic succession of this unit is composed of a lower meta-detrital formation overlain by an upper meta-carbonate formation divided in six members. In the latter, a Ladinian–Carnian-rich fossil association has been found (foraminifers, algae, bivalves, microproblematica, trace fossils). Facies analysis has enabled the recognition of 22 facies of platform origin. This succession accumulated as a subsiding margin-type carbonate platform with homoclinal ramp geometry (Anisian?–Ladinian) evolving into a fault-block-type platform with a steeper-margined geometry (Ladinian–Carnian). Slope deposits of this latter platform show a prism-like geometry with progradational patterns and include syn-sedimentary structures associated with normal faults capped by younger beds. The results of the present research indicate that the architecture of the platform studied has been controlled mainly by climate and oceanic factors during the development of the ramp, and by syn-sedimentary extensional tectonics during the development of the steeper-margined platform. The Ladinian–Carnian tectonic activity was probably also responsible for the siliciclastic input and the shift to a mixed terrigenous-carbonate platform.

The Ossa de Montiel (2015/02/23, Mw 4.7) earthquake struck the central part of Spain and was felt far from the epicenter (> 300 km). Even though ground shaking was slight (Imax = V, EMS-98 scale), the earthquake triggered many small rock falls, most at distances of 20–30 km from the epicenter, greater than previously recorded in S Spain (16 km) for earthquakes of similar magnitudes. The comparative analysis of available data for this event with records from other quakes of the Betic cordillera (S and SE Spain) seems to indicate a slower pattern of ground-motion attenuation in central Spain. This could explain why slope instabilities occurred at larger distances. Instability was more frequent, and occurred at larger distances, in road cuts than in natural slopes, implying that such slope types are highly susceptible to seismically induced landslides. This work has been funded by Spanish Ministry of Economy and Competitiveness, research project CGL2011-30153-C02-02, and by the research groups RNM-374 (Junta de Andalucía), TECTAC (UCM-910368) and VIGROB-184 (Universidad de Alicante). Mr. Loffredo acknowledges funding of the Università di Roma — La Sapienza (post-graduate grant) (Concorso A N.480 - Area CUN 04).

Tectonic units of the Sierra Espuña-Mula area are described in order to characterize the palaeogeographic passage from the Alpujarride to the Malaguide Complexes through the “intermediate units”. Moreover, the Meso-Cenozoic cover of the Malaguide units in this area show the transition from the Malaguide to the “Internal Dorsal”. Both features are relevant for the palaeogeographic reconstruction and geodynamic evolution of the Betic-Rif Internal Zone (BRIZ) in the framework of the Alpine Perimediterranean Chains. These data, together with others from other sectors of the Betic-Rif Cordillera enable us to propose a palaeogeography during the Triassic rifting with two subsident areas related to two oceanic branches (the Nevadofilabride-Alpujarride to the north, and the Maghrebian, to the south) separated by a continent or shallow marine area (the Malaguide). These branches were closed during post-rifting geodynamic evolution including two different piling phases: a first top-to-the-north in the northern branch (Alpine tectogenesis, Latest Cretaceous-Middle Oligocene); a second top-to-the-south in the southern branch (Maghrebian tectogenesis, Late Oligocene-Early Miocene). The opposite arrangement of units in the Betic with respect to the Rif required clockwise rotations to form the Gibraltar Arc, confirmed by data from the literature. These rotations are related to the westward displacement and subsequent collision of the BRIZ against the African and Iberian palaeomargins.

Jurassic studies in the Internal Zones of the Betic Cordillera are scarce since this zone is composed mainly of pre-Jurassic metamorphic rocks. Only the “Dorsal” and the Malaguide domains include fossiliferous Jurassic successions, as in Sierra Espuna (SE Spain), which is one of the bigger and well-exposed Jurassic outcrops of the Internal Zones. Collected Ammonite assemblages update and improve the precision of previous biostratigraphic data by the recognition of: the Domerian (= Upper Pliensbachian, in the Mediterranean Domain) Lavinianum (Cornacaldense Subzone), Algovianum (Ragazzoni, Bertrandi, Accuratum and Levidorsatum Subzones) and Emaciatum (Solare and Elisa Subzones) Zones; the Lower Toarcian Polymorphum and Serpentinum Zones; the Middle Toarcian, Bifrons and Gradata Zone; the Upper Toarcian Reynesi Zone; the Lower/Upper Bajocian, the Lower Callovian Bullatus and Gracilis Zones; the Middle/Upper Oxfordian Transversarium, Bifurcatus, Bimammatum and Planula Zones; and the Lower and Upper Kimmeridgian Platynota, Strombecki, Divisum and Beckeri Zones. The paleoenvironmental evolution of the Malaguide Jurassic at Sierra Espuna shows similarities with other Mediterranean Tethyan paleomargins. The biostratigraphic precision along with the litho- and biofacies analyses has enabled the interpretation that the Malaguide paleomargin evolved as a passive margin, developing shallow carbonate platforms, until the Domerian (Lavinianum Zone). Then, the platform broke up (Domerian, Lavinianum Zone–Upper Toarcian, Reynesi Zone) with the beginning of the rifting stage, beginning the development of horst–graben systems and the coeval drowning of the area. This stage ended in the upper Lower Callovian (Gracilis Zone) to the Middle Oxfordian (Transversarium Zone) interval, starting the drifting stage, which accentuated the horst–graben systems, leading to the deposition of condensed nodular limestones in the raised sea bottom.

The Calabria–Peloritani Arc southern terrane is a stack of crystalline basement nappes, some of them provided with a widely outcropping Alpine sedimentary cover, sealed by clastics of the Stilo–Capo d’Orlando Formation (SCOF). New field observations in the Stilo area lead to define a Pignolo Formation as a sedimentary cycle predating the emplacement of the uppermost nappe (Stilo Unit) of the tectonic pile. It includes the well-known Lithothamnium and larger foraminifers bearing calcarenites, previously interpreted as a basal member of the SCOF. The biostratigraphic revision of both formations, together with recently published data about other preorogenic deposits, point to a stacking of the whole terrane between the Aquitanian and the middle–late Burdigalian. A comparison between the sedimentary cycles characterising the Calabria–Peloritani southern terrane during the Oligocene–Early Miocene and those almost coeval of the Betic–Rifian internal units highlights their quite similar evolution. Thus it is reliable that both the orogenic belts originated from contiguous paleogeographic realms. These considerations confirm that the present western Mediterranean Chains were originally segments of a continuous orogenic belt disrupted by the opening of the Balearic and Tyrrhenian basins.

A study has been performed on the Cretaceous to Early Miocene succession of the Vrancea Nappe (Outer Carpathians, Romania), based on field reconstruction of the stratigraphic record, mineralogical-petrographic and geochemical analyses. Extra-basinal clastic supply and intra-basinal autochthonous deposits have been differentiated, appearing laterally inter-fingered and/or interbedded. The main clastic petrofacies consist of calcarenites, sub-litharenites, quartzarenites, sub-arkoses, and polygenic conglomerates derived from extra-basinal margins. An alternate internal and external provenance of the different supplies is the result of the paleogeographic re-organization of the basin/margins system due to tectonic activation and exhumation of rising areas. The intra-basinal deposits consist of black shales and siliceous sediments (silexites and cherty beds), evidencing major environmental changes in the Moldavidian Basin. Organic-matter-rich black shales were deposited during anoxic episodes related to sediment starvation and high nutrient influx due to paleogeographic isolation of the basin caused by plate drifting. The black shales display relatively high contents in sub-mature to mature, Type II lipidic organic matter (good oil and gas-prone source rocks) constituting a potentially active petroleum system. The intra-basinal siliceous sediments are related to oxic pelagic or hemipelagic environments under tectonic quiescence conditions although its increase in the Oligocene part of the succession can be correlated with volcanic supplies. The integration of all the data in the “progressive reorientation of convergence direction” Carpathian model, and their consideration in the framework of a foreland basin, led to propose some constrains on the paleogeographic-geodynamic evolutionary model of the Moldavidian Basin from the Late Cretaceous to the Burdigalian. This research was supported by Urbino University grant (responsible F. Guerrera), Italy; CGL2009-09249 and CGL2011-30153-CO2-02 research projects (Spanish Ministry of Education and Science), Research Groups and projects of the Generalitat Valenciana and from Alicante University (CTMA-IGA Spain); Research Contr. IDEI 436/01.10.2007 (CNCSIS-Romania).

Evidence is presented for Triassic rift-related palaeo-structures from the Alpujarride Complex carbonates of the Betic Cordillera, SE Spain. Direct evidence of syn-sedimentary extensional tectonics is provided by the recognition of a macro- to meso-scale normal fault system overstepped by younger strata. Most of the faults define domino-like horst and graben structures. The faults are associated with an expanded syn-rift sedimentary prism in which soft-sediment deformation, gravity-flow deposits and unconformities are widely developed. Syn-tectonic mafic igneous intrusions have also been identified. The age of this phase of extension is well constrained as Ladinian-Carnian (c. 237 – 216 Ma). From a palaeotectonic and palaeogeographic standpoint, the thick Triassic carbonates of the Betic Internal Zone and Southern Apennine (Northern Calabria) occupied a belt with elevated subsidence connecting the Neo-Tethys rifting to the east and the eastern North American rift system to the west. Their carbonate facies, intermediate between classical Alpine-type and Germanic-type facies, recorded the main episodes of rifting affecting Central Pangea.

In the Sierra de Gádor (Almeria province) terrains belonging to the Internal Betic Zone crop out. According to stratigraphic, structural and petrologic features we have recognised five tectonic units. These units are called, from bottom to top, Gádor-Turón, Laujar, Murtas, Felix and Chirán unit. The lower fourth are ascribed to the Alpujárride Complex, whilst the last one is ascribed to the Maláguide Complex. We also discuss if the Felix unit may be included in the Intermediate Units. The Felix unit represents the Triassic palaeogeographic transition between the Alpujárride and the Maláguide, and it was located between both complexes during the alpine tectono-metamorphic evolution of the Betic Cordillera. En la Sierra de Gádor (provincia del Almería) afloran rocas pertenecientes a la Zona Interna de la Cordillera Bética. En este sector hemos reconocido un total de cinco unidades tectónicas, en función de sus características estratigráficas, estructurales y petrológicas. Estas unidades se denominan, de abajo a arriba, unidad de Gádor-Turón, unidad de Laujar, unidad de Murtas, unidad de Felix y unidad de Chirán. Las cuatro más bajas las asignamos al Complejo Alpujárride, mientras que la más alta la asignamos al Complejo Maláguide. Se discute además la posible inclusión de la unidad de Felix dentro de las denominadas Unidades Intermedias. La unidad de Felix representa el tránsito paleogeográfico durante el Triásico entre el dominio Alpujárride y el Maláguide, y estaría situada entre ambos complejos durante la evolución tectono-metamórfica alpina de la Cordillera Bética.

In this work, we present a detailed analysis of brittle and brittle-ductile structures related to the contacts of a stack of tectonic units cropping out in the Sierra Espufta (Betic Cordillera, southern Spain). These data show two superposition stages with opposing transport directions: first, a top-to-the-north (according to current coordinates) stage (Oligocene in age), and a second stage from the Middle Oligocene-Aquitanian, with a top-to-the-north sense of transport. In the Burdigalian, the Internal Betic Zone units of the Sierra Espuna sector could rotate near 180° because of the oblique collision against the External Zones, and therefore the previous stacking directions went in the contrary direction with respect to that measured nowadays. The reconstruction of movements shows that the Malaguide Complex was situated to the south of the Alpujarride prior to the Alpine tectonics, which is in good agreement with previous

Mapping, lithostratigraphic, biostratigraphic and structural detailed analyses in Sierra Espuña area (Internal Betic Zone, SE Spain) have allowed us to reconstruct the Jurassic–Cretaceous evolution of the Westernmost Mesomediterranean Microplate palaeomargin and, by correlation with other sectors (Northern Rift, central and western Internal Betic Zone), to propose a geodynamic evolution for the Westernmost Tethys. Extension began from Late Toarcian, when listric normal faults activated; these faults are arranged in three categories: large-scale faults, separating hectometric cortical blocks; main faults, dividing the former blocks into some kilometre-length blocks; and secondary faults, affecting the kilometric blocks. This fault ensemble, actually outcropping, in the Sierra Espuña area, broke the palaeomargin allowing the westerly Tethyan Oceanic aperture with an extension at about 17.2%. Extension was not homogeneous in time, being the Late Toarcian to the Dogger–Malm boundary the period when blocks underwent the greatest movement (rifting phase), leading to the drowning of the area (8.2% extension). During the Malm (drifting phase) extension followed (5.7%), while during the Cretaceous a change to pelagic facies is recorded with an extension of about 3.3% ( post-drift stage). This evolution in the Westernmost Tethys seems to be related to areas out of the limit of significant crustal extension in the hanging wall block of the main cortical low-angle fault of the rifting.

New studies have been carried out on the Tertiary of the Stilo Unit, the uppermost of the Calabria–Peloritani Arc southern sector, and the Stilo–Capo d'Orlando Formation, sealing the whole nappe stack. The Tertiary terrains linked to the Mesozoic cover of the Stilo Unit consist of the lowermost Oligocene Palizzi Formation and the Late Rupelian–Aquitanian Pignolo Formation. The possibility that they deposited before the emplacement of this unit as the highest tectonic sheet of the sector is suggested. The base of the Stilo–Capo d'Orlando Formation resulted of Burdigalian age in both type areas. This interpretation, together with the existing and new data, allows proposing an age close to the Aquitanian–Burdigalian boundary for the stacking of the whole Calabria–Peloritani Arc southern sector. To cite this article: G. Bonardi et al., C. R. Geoscience 334 (2002) 423–430.

Summary Faults are rarely a discrete two-dimensional surface, but a three-dimensional volume with a complex internal structure. The structure of a fault zone in 3D is poorly understood, particularly because outcrops exposing fault zones in 3D are rare, and few have large (e.g. 100 m) throw. Detailed 3D studies of fault zones can help provide insight into their internal structure, and processes undergone during faulting as well as improve the predictability of subsurface (e.g. reservoir) models. The main objective of this project is to construct a 3D structural model of a strand of the Baza fault, an active normal fault located in south central Spain in the Betic Cordillera. This strand has an estimated throw of 30 m in relatively unconsolidated clay to silt and carbonates Pliocene sequence. Through a trenching study, 8 vertical dip sections, 3 vertical strike sections and 1 depth section in an area of approximately 80 mA2 were excavated, cleaned, LiDAR scanned, photographed and documented. Based on these sections, we have reconstructed the 3D geometry and associated structures of this superb fault zone. These data can also be useful for geophysical and reservoir modeling studies

In this paper, we present the results of the stratigraphic and structural study of the Orihuela and Callosa Mountains (Alicante province, SE Spain), belonging to the Internal Betic Zone. The terrains cropping out in this area had been assigned by previous authors to the Ballabona-Cucharón Complex, lately redefined as the Almágride Complex. New data afforded in this work lead us to propose a new stratigraphic succesions, structural division, and geodynamic evolution. We also assign both mountains ranges to the lower Alpujarride Complex, confirming that the Almágride Complex is not a singular element of the Betic Cordillera. En este trabajo presentamos los resultados del estudio estratigráfico y estructural de las sierras de Orihuela y Callosa (provincia de Alicante, SE de España), pertenecientes ambas a la Zona Interna Bética. Estas sierras fueron asignadas por autores precedentes al Complejo Ballabona-Cucharón, más tarde redefinido como Almágride. Los datos presentados en este trabajo nos llevan a proponer una nueva serie estratigráfica, división tectónica y evolución geodinámica del sector estudiado. Así mismo, asignamos las unidades reconocidas a la parte inferior del Complejo Alpujárride, confirmando que el Complejo Almágride no debe ser considerado como elemento singular de la Zona Interna Bética. This study was supported by the research projects BTE2003-01113 and CGL2006-08848, and by research groups GR00/222 y GR01-62.