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En este trabajo se estudian las variaciones observadas en las asociaciones de foraminiferosl bentonicos en relacion con cambios paleoambientales, en los sedimentos de! Plioceno inferior del Palmo de Salas, N de la cuenca de Almeria-Nijar (SE de la Peninsula Iberica). Los cambios en las asociaciones de foraminiferos bentonicos ponen de manifiesto una somerizacion hacia el techo, desde facies de plataforma externa en la base de la seccion, a facies de plataforma interna somera en el techo. Un analisis "cluster" binario cualitativo pone de manifiesto un relevo de tres agrupaciones diferentes que refleja dicha somerizacion. La base de la seccion esta caracterizada por una asociacion de foraminiferos bentonicos dominada en casi un 50% por Cassidulina neocarinata . Estos materiales corresponden a los depositos mas profundos, formados en un medio disaerobico. Las facies mas someras, hacia el techo de la seccion, estan caracterizadas por una asociacion dominada por los generos Ammonia, Nonion, Cribroelphidium y Elphidium . Las facies de plataforma media estan caracterizadas por asociaciones mas diversas y con gran abundancia de especies, dominando Nonion asterizans, Elphidium spp., Lenticulina calcar , Cibicides spp. y Asterigerinata planorbis. Finalmente, un analisis "cluster" cuantitativo en modo "Q" pone de manifiesto, ademas de las asociaciones que estan controladas por la batimetrfa, la existencia de subgrupos que caracterizan ambientes empobrecidos en oxigeno (disaerobicos), dominados por los generos Bulimina, Hopkinsina, Cassidulina y Brizalina , y ambientes con un fondo cubierto por algas, caracterizados por una asociacion de forarniniferos tipicamente epifiticos ( Elphidium crispum , E. macellum, Cribroelphidium decipiens, Cibicides refulgens y C. lobatulus ).

L. A. M. Rocha gratefully acknowledges funding from the Fundação para a Ciência e Tecnologia (FCT), Portugal (grant SFRH/BD/130401/2017). C. Pimentel acknowledges funding from Juan de la Cierva‐Formación (grant FJC2018‐035820‐I) from the Spanish Ministry of Science. J. H. E. Cartwright and C. Ignacio Sainz‐Díaz acknowledge the financial support of the Spanish MINCINN projects FIS2016‐77692‐C2‐2‐P and PCIN‐2017‐098. I. Sánchez‐Almazo thanks the crew of the Cornide de Saavedra vessel, as well as the members of the Tasyo project, funded by the Spanish Marine Science and Technology Program, for allowing her to participate in the 2000–2001 Anastasya cruises. The authors acknowledge the contribution of the COST Action chemobrionics, CA17120., Methane-rich water moves through conduits beneath the seafloor whose surfaces are formed through precipitation reactions. To understand how such submarine fluid conduit and venting systems form and grow, we develop a detailed mathematical model for this reaction-advection system and we quantify the evolution of an ensemble of similar filaments. We show that this growth can be described by a superposition of advection and dispersion. We analyze analog laboratory experiments of chemical-garden type to study the growth of a single filament undergoing a precipitation reaction with the surrounding environment. We apply these findings to geological fluid conduit and venting systems, showing that their irregular trajectories can lead to very effective spreading within the surrounding seabed, thus enhancing contact and exchanges of chemicals between the conduit and external fluids. We discuss how this methane venting leads to the formation of marine authigenic carbonate rocks, and for confirmation, we analyze two field samples from the Gulf of Cadiz for composition and mineralogy of the precipitates. We note the implications of this work for hydrate melting and methane escape from the seabed., Ciencia e Tecnologia, Fundação para a Ciência e Tecnologia, MINCINN PCIN‐2017‐098, European Cooperation in Science and Technology CA17120, Fundação para a Ciência e a Tecnologia FJC2018‐035820‐I, SFRH/BD/130401/2017, Ministerio de Ciencia e Innovación

The authors acknowledge funding from Spanish MINCINN project grant FIS2016-77692-C2-2P along with European FEDER funds the European COST Action CA17120 supported by the EU Framework Programme Horizon 2020, and the PCIN-2017-098 project., We have performed and visualized chemical garden growth experiments directly in situ in an environmental scanning electron microscope. The microscope chamber simulates the surface of Mars. We demonstrate that chemical gardens can form under the conditions of temperature and pressure existing on Mars in the presence of liquid water, silicates, and metal salts. Using chemical gardens from aluminum salts, tubes were formed where the external surface is formed principally by silicate and the inner surface is predominantly aluminum oxide-hydroxide. It should thus be expected that similar growths of metal salts may be found in geological explorations of water-rich environments during the search for life on Mars., Spanish MINCINN project FIS2016-77692-C2-2P, European FEDER funds the European COST Action by the EU Framework Programme Horizon 2020 CA17120 PCIN-2017-098

Microbialites are volumetrically abundant components in Last Glacial Maximum and deglacial reefs in the Australian Great Barrier Reef sampled by IODP Expedition 325 in 34 holes from 17 sites (M0030–M0058), along four transects on the shelf edge. Detailed radiometric datings show that four distinct reef phases developed between 28and 10 ka, displaying offlapping and then backstepping patterns. The reef boundstone facies include coralgal, coralgal-microbialite and microbialite boundstone. The microbialite consists of combinations of micrite/microspar, bioclasts, siliciclastic grains (up to 14.5%), fenestrae and encrusting epibionts. The micrite/microspar is high-magnesian calcite commonly irregularly clotted, fenestral and peloidal. Mesoscale microbialite fabrics include laminated, structureless, digitate, intraskeletal and boring-filling, and coatings on debris. Intraskeletal and boring-filling is the first fabric to develop in skeletal voids and borings. It is usually followed by structureless and laminated microbialite, locally overlain by digitate fabric. Microbialite-coated debris can occur at any stage in this succession, including in bioclastic accumulations where the scarce in situ framework builders are mainly encrusting corals. Lipid biomarkers of intermediate to high specificity for sulfate-reducing bacteria, together with δ13C values of these lipids, indicate that microbialite formation was favored by sulfate-reducing bacteria in anoxic microenvironments, probably under high nutrient levels. The microbialite in fore-reef deposits accumulated in the photic zone in water depths of a few to several tens of meters, within small spaces generated by large bioclasts and encrusting corals in the topmost centimeters of the sediment. These crusts that formed on the illuminated surface constitute a previously unrecognized style of microbialite formation in Quaternary reefs. As with the cryptic crusts described from other reef locations, its greatest development occurred during the Last Glacial Maximum and early deglaciation. Microbial carbonate formation during this interval may reflect elevated seawater carbonate saturation corresponding with relatively low levels of atmospheric CO2.

Upper Miocene heterozoan carbonates crop out extensively in a NE–SW-trending belt (42 km long and 1.5–8 km wide) along the so-called El Alcor topographic high, from Carmona to Dos Hermanas (Seville, S Spain). These carbonates formed at the southern active margin of the Guadalquivir Basin, the foreland basin of the Betic Cordillera. They change to marls basinward (NE) and to sands landward (SE and SW). Therefore, carbonate production was constrained to a limited area in an otherwise siliciclastic shelf. The carbonates (up to 40 m thick) overlie a gradually coarsening-upward succession of marls followed by silts and sandstones. The carbonate sequence can be divided into three subunits corresponding, from bottom to top, to lowstand, transgressive, and highstand system tract deposits. The lower subunit, exhibiting extensive trough cross-bedding, is interpreted as a shallow-water bar deposit. The intermediate subunit onlaps underlying sediments and was deposited in deeper, low-turbulence conditions. The upper subunit deposits accumulated in a well-oxygenated outer platform based on benthic foraminiferal assemblages. The presence of hummocky and swaley cross-stratification in these latter deposits suggests that they were affected by storms. Pervasive fluid-escape structures are also observed throughout the carbonates. The three subunits consist of bioclastic packstones to rudstones made up of abundant fragments of small mytilids. Isotopic data from serpulid polychaete Ditrupa tubes show 13C-depleted values (up to − 16.1‰), whereas δ18O yields normal marine values. Additional isotopic data on shells of scallops, oysters, and small mussels, as well as bulk sediment, show diagenetic alterations. Based on actualistic examples of massive concentrations of mussels, the nearly monospecific composition of the El Alcor deposits, together with negative δ13C values of Ditrupa tubes, indicates that cold seeps presumably promoted carbonate formation. However, the absence of typical features of cold-seep deposits, such as authigenic carbonates mediated by anaerobic bacterial activity and the typical chemosynthetic shelly organisms, makes the large carbonate body of El Alcor an unusual cold-seep deposit.

Spectral analysis of the Messinian Abad marls in the Cariatiz section (Sorbas Basin, south-eastern Spain) reveals three relevant orders of cyclicity. The most significant cycle is in the lowest frequency (average thickness of 365 cm, 4–5 cycles in the section). It is recorded in the composition of planktic foraminiferal assemblages indicative of surface-water temperature, planktic and benthic stable isotope signals, and carbonate proportions. The planktic assemblages, isotope values and carbonate proportions also record a middle-frequency cycle with an average of 177 cm (9–10 cycles in the section). The highest frequency cycle (average of 132 cm, 12–13 cycles in the section) is mainly reflected in siliciclastic and calcite proportions. Age constraints and cycle patterns suggest that the lowest frequency cycle was forced by orbital obliquity, whereas the two higher-frequency ones are related to precession. Obliquity seems to have controlled major changes in surface-water temperature in the Sorbas Basin during the early Messinian. Surface-water temperature was also affected by precession, with changes in weathering and run-off. Spectral analysis has also been applied to vertical shifts of reef facies throughout the progradation of the Cariatiz reef. This reef is coeval with the Cariatiz section. Vertical shifts of reef talus breccias point to the existence of 4–5 major cycles of sea-level change, whereas 7–9 higher-frequency cycles are reflected in the repeated occurrence of lowstand, non-reefal deposits. Correlation with the cycles observed at the Cariatiz section suggests that obliquity forced glacio-eustatic sea-level oscillations in the western Mediterranean during the Late Miocene.

The Nisa-Alburquerque granitic batholith (southern Variscan Belt, Iberian Peninsula) has been studied by petrological, structural and geophysical approaches, obtaining contrasting models for its deep structure and emplacement sequence. In order to test these models and gain knowledge on the thermal increase induced by the intrusion, we have studied its contact aureole, which was developed in similar country rock lithologies (mica schists alternating with metasandstones and feldespatic schists) all along the northern external contact of the batholith. Our results indicate no change in metamorphic grade and some variations in aureole width, which narrows toward the western sectors of the batholith. Cordierite is the only contact metamorphic mineral developed together with a high temperature biotite probably related to the granite thermal input. By considering these new data, together with zircon saturation temperatures within the granite and previous petrological and geophysical studies, we propose a model in which the feeder zones of the granitic magmas were an eastern main one and a western secondary one. We have also made comparisons of the metamorphic grade in the country rocks and the xenoliths within the granite. Most of the xenoliths have the same metamorphic facies as the country rocks (Crd-zone), though some of them contain slightly different assemblages (And + Crd), which could be explained in different ways: (1) differences in the primary schist compositions, (2) increased time-span of xenoliths in contact with the melt and (3) xenolith incorporation at slightly higher depths during final granite ascent.

During the Late Tortonian, platform-margin-prograding clinoforms developed at the south-western margin of the Guadix Basin. Large-scale wedge-shaped deposits here comprise 26 rhythms of mixed carbonate–siliciclastic bedset packages and marl beds. These sediments were deposited on a shallow-water, temperate-carbonate distally steepened ramp. A downslope-migrating sandwave field developed in this ramp, with sandwaves moving progressively down the ramp to the ramp-slope, where they destabilized, folded and occasionally collapsed. Downslope sandwave migration was induced by currents flowing basinwards. During the Late Tortonian, the Guadix Basin was open north to the Atlantic Ocean via the Dehesas de Guadix Strait and connected east to the Mediterranean Sea through the Almanzora Corridor. According to the proposed current circulation model for the Guadix Basin for this time, surface marine currents from the Atlantic entered the basin from the northern seaway. These currents moved counter-clockwise and shifted the sediment on the ramp, forming sandwaves that migrated downslope. The development of platform-margin prograding clinoforms by the basinward sediment-transport mechanisms inferred here is known relatively poorly in the ancient sedimentary record. Moreover, these wedge-shaped geometries are similar to those found in some shelves in the Western Mediterranean Sea and could represent an outcrop analogue to (sub)-recent, platform-margin clinoforms revealed by high-resolution seismic studies.

The Cariatiz section lies at the toe of the palaeoslope of the Messinian Cariatiz fringing reef, at the northern margin of the Neogene Sorbas Basin in SE Spain. Distal-slope reef deposits in the upper part of the section can be traced laterally to the reef core of the last episodes of reef progradation. The underlying deposits are alternating diatomitic marl, marl and silty marl that intercalate with sandstone beds. Combined lithological changes, variations in proportions of warm-water planktic foraminifera and δ18O values suggest that at least seven, probably precessional, cycles are recorded throughout the Cariatiz section. The correlation of seven cycles in the pelagic deposits to seven reef progradation cycles, and associated vertical shifts in reef facies, indicates relative sea-level oscillations of several tens of metres. Biostratigraphic and palaeomagnetic data suggest that both the Cariatiz section and the fringing reef formed during the reverse polarity Chron C3r. Surface-water temperatures seem to be the major factor controlling carbonate production in the reef system. Deposition of bioclastic calcirudite and calcarenite, with no active coral growth, took place at the lowest sea-level within each reef cycle during temperature minima within each precessional cycle. Porites framework and reef-slope deposits with Halimeda gravel, in contrast, formed during temperature rises and thermal maxima within precessional cycles.

Cuttlebone, the sophisticated buoyancy device of cuttlefish, is made of extensive superposed chambers that have a complex internal arrangement of calcified pillars and organic membranes. It has not been clear how this structure is assembled. We find that the membranes result from a myriad of minor membranes initially filling the whole chamber, made of nanofibres evenly oriented within each membrane and slightly rotated with respect to those of adjacent membranes, producing a helical arrangement. We propose that the organism secretes a chitin–protein complex, which self-organizes layer-by-layer as a cholesteric liquid crystal, whereas the pillars are made by viscous fingering. The liquid crystallization mechanism permits us to homologize the elements of the cuttlebone with those of other coleoids and with the nacreous septa and the shells of nautiloids. These results challenge our view of this ultra-light natural material possessing desirable mechanical, structural and biological properties, suggesting that two self-organizing physical principles suffice to understand its formation., This research was funded by projects CGL2010-20748-CO2-01 (to A.G.C. and F.R.R.), CGL2013-48247-P (to A.G.C. and I.S.A.) and FIS2013-48444-C2-2-P (to J.H.E.C.) of the Spanish Ministerio de Ciencia e Innovación, and RNM6433 (to A.G.C., J.H.E.C. and I.S.A.), of the Andalusian Consejería de Innovación Ciencia y Tecnología, and 31.03.05.FEP.002 (Sepiatech, PROMAR program) of the Portuguese Ministério da Agricultura e do Mar, Portugal (to J.P.A.). A.G.C. and J.H.E.C. also acknowledge the Research Group RNM363 (Junta de Andalucía) and the FP7 COST Action TD0903 of the European Community.

Neogene intermontane basins in Almeria Province, SE Spain, display excellent exposures of Messinian (Late Miocene) sequences. The Sorbas, Almeria-Nijar and Vera basins maintained connection with the Mediterranean throughout the Messinian, except during the major desiccation phase leading to the formation of salt in the deep centre of the Western Mediterranean. These basins were part of the Western Mediterranean with no separate link to the Atlantic Ocean. The presence of normal marine sediments in these basins reflects the Western Mediterranean watermass. Messinian pre-evaporitic sediments in the basins of southeastern Almeria do not show gradual change towards evaporite deposits. Instead they contain stenohaline invertebrates right up to a major erosion surface that separates them from overlying gypsum deposits. This contradicts suggestion of progressive salinity increase in this part of the Western Mediterranean prior to the Messinian Salinity Crisis (MSC); it also indicates that initiation of evaporite precipitation was not synchronous throughout the Mediterranean Basin. There is no major erosion surface within or at the top of the evaporites in these Almeria basins, and the gypsum beds exhibit upward transition to siliciclastic and carbonate deposits. This is inconsistent with a model of Messinian Mediterranean evaporite formation whereby deposition of marginal evaporites was followed by their erosion during drawdown that resulted in formation of evaporites in the centre of the Western Mediterranean. The presence of stenohaline biotas in siliciclastic deposits interbedded with the gypsum and in the Messinian post-evaporitic sediments, challenges the view that a long-standing large body of brackish water (the Lago Mare) filled the Western Mediterranean following the MSC and prior to Early Pliocene flooding. It also contradicts the concept of many relatively small brackish basins spread across an otherwise desiccated Western Mediterranean basin. The basins of southeastern Almeria record normal marine Early Messinian sedimentation that was abruptly interrupted by sealevel fall. This drawdown most likely resulted in precipitation of evaporites in the central deep Western Mediterranean basin. Following this episode, final marine reflooding of the Western Mediterranean took place during the Late Messinian, and the Mediterranean Sea rose to a level similar to, or higher than, that preceding the Salinity Crisis.

During the late Tortonian (upper Miocene), the Guadix Basin in S Spain formed one of the Betic corridors that connected the Mediterranean Sea with the Atlantic Ocean. The closure of this connection occurred in a series of steps, documented by three sedimentary units. A lower unit, consisting of basinal marls, shallow-water calcarenites and sands records the formation of a wide seaway. During deposition of the following unit this narrowed to a strait no more than 2 km in wide, triggering an intensification of currents that caused migration of submarine dunes preserved as giant cross-beds in bioclastic sands and conglomerates. Current flowed from the Mediterranean to the Atlantic. The third unit constitutes the youngest marine episode of the filling of the Guadix Basin. At this stage, the connection between the Mediterranean Sea and the Atlantic Ocean was broken, and a system of coastal coral reefs was established in the northern part of the Basin.

The exceptional exposures of the evaporitic and post-evaporitic Messinian deposits in the Gafares area (NE Almeria-Nijar basin, SE Spain) make it possible to elucidate those processes affecting this region during the critical period of the Messinian Salinity Crisis. The contact between the pre-evaporitic and the evaporitic units is an erosional unconformity. The transition from the evaporitic to the post-evaporitic units is gradual, since the gypsum beds of the evaporitic unit thin upward and the siliciclastic interbeds concomitantly thicken, thus passing gradually to the overlaying post-evaporitic unit. The presence of Globorotalia miotumida group in the last pelitic intercalation of the evaporitic unit as well as throughout the post-evaporitic one indicates a Messinian age. The post-evaporitic unit consists of a variety of sediments formed in continental and marine settings. Continental facies are characterised by fluvial channel-filled conglomerates and alluvial-plain sands and silts. Marine sediments are represented by silty marls with foraminifers. A river-dominated delta developed in the transitional zone at the NW edge of the Gafares area. Localised fan-delta deposits coming from the ESE also occur in the southeastern part of the study area. Microbial carbonates locally colonised the fan-delta conglomerates. During the deposition of the lower half of the post-evaporitic unit, sedimentation took place in a sheltered embayment, with restricted water circulation and relatively isolated from the Mediterranean Sea by an E–W-trending sill located at the south of the study area. In this palaeogeographic context, freshwater influx from the delta exerted a certain influence on the distribution of microorganisms. Thus, brackish settings developed close to the river outflows that were occupied by caspibrackish ostracod assemblages. The presence of gastropods of the family Cerithiidae as well as fishes attributable to the genus Aphanius , organisms that preferentially inhabit sheltered lagoons, is consistent with these settings. Beyond the freshwater influx, foraminifers dominated the microfossil assemblages. In the upper half of the post-evaporitic unit, microfossil assemblages dominated by planktonic forms are consistently found, thus revealing a better connection of the semi-enclosed Gafares area with the marine domain. This is related to the deepening of the sill due to a progressive rise of the sea level. The continental and brackish deposits (Zorreras-like facies) have been equated with the “Lago-Mare” facies, which were supposed to spread throughout the whole Mediterranean at the end of the Messinian. Nevertheless, in the Gafares area, these deposits change laterally to and interbed with marine deposits. This stratigraphic architecture and facies relationship has two important implications. On the one hand, marine waters at the latest Messinian occupied at least the western Mediterranean, predating the long-claimed early Pliocene deluge. On the other hand, the continental-brackish “Lago-Mare” facies were spatially restricted. As a consequence, neither the presence of the caspibrackish ostracods nor the continental-brackish facies can be plausibly taken to support the hypothesis that widespread “Lago-Mare” facies occupied the whole Mediterranean synchronously at the end of the Messinian. Therefore, this type of facies is expected to be found (albeit with varying degrees of development) in marginal basins at different times but not throughout the Mediterranean.

Lateral facies changes from upper Tortonian^Messinian marginal carbonates into pelagic marls can be physically traced in two well-exposed sections of the Sorbas Basin, SE Spain. Due to this physical correlation, the foraminifer assemblages from the marls and the oxygen and carbon isotope values of the foraminifer tests can be used to reconstruct the palaeoenvironmental context of deposition of the laterally equivalent carbonates. At the basin margins, an uppermost Tortonian/lowermost Messinian temperate carbonate unit with bryomol and rhodalgal lithofacies is overlain by two successive Messinian reef units comprising coral and Halimeda bioherms and fringing Porites reefs respectively. All these units interfinger basinwards into silty marls and marls. The N 18 O values of both planktonic and benthic foraminifers from the pelagic marls coeval with the temperate carbonates are higher than those from the fine-grained sediments laterally equivalent to the overlying reefs (by 1.91x in the planktonic and 1.67x in the benthic records). This decrease in N 18 O, together with an increase in the abundance of subtropical/tropical species in planktonic foraminifer assemblages, confirms a rise in sea-surface temperatures in the change from bryomol/rhodalgal to reef carbonate deposition. Carbonate lithofacies in the upper Miocene in the Sorbas Basin are, therefore, primarily controlled by temperature. The low carbon isotope signatures and the benthic foraminifer assemblages in the pelagic sediments coeval with reefs point to poorly oxygenated bottom waters and strong stratification. fl 2001 Elsevier Science B.V. All rights reserved.

The extent, timing and effects of Late Miocene desiccation and evaporite deposition in the Mediterranean Sea remain controversial. Marginal basins containing Messinian (5.3–7.1 Ma) sequences now exposed onland supplement information from the deep Mediterranean, but have evaporites of a variety of ages. Some of these Messinian evaporites pre-date, and others post-date, deep desiccation. None appears to be exactly coeval with those of the deep Mediterranean. In the Betic Cordillera of southern Spain, basins (e.g. Granada Basin) far from the present-day Mediterranean lost connection with the Mediterranean due to uplift ∼1 Ma before the Salinity Crisis, and have marine evaporites of early, not late, Messinian age. In contrast, basins such as the Sorbas Basin in southeastern Spain, adjacent to the present-day Mediterranean, record events directly reflecting the course of the Salinity Crisis. The Sorbas Basin retained marine connection with the western Mediterranean up until evaporative drawdown in the mid-Messinian and was rapidly reflooded immediately afterwards. The Sorbas Messinian sequence is up to 320 m thick. It is complete and normal marine, except for an incised basinwide erosion surface overlain by a 130 m thick gypsum deposit. We propose that this surface marks the interval of deep desiccation of the adjacent Mediterranean basin. Erosion occurred shortly after 5.9 Ma and the irregular unconformity has relief of at least 240 m, confirming Mediterranean drawdown significantly below the Atlantic level. Sorbas gypsum deposits overlie the unconformity and are intercalated with marls estimated at ∼5.5 Ma containing normal marine Messinian biotas. These gypsum deposits therefore post-date deep desiccation and formed in a silled basin immediately following marine reflooding. They mark the end of the Salinity Crisis and are overlain by 70 m of normal marine sediments containing unreworked foraminifers of latest Messinian age. This succession demonstrates that the Salinity Crisis occurred faster and was completed sooner than previously believed. It took place within ∼0.4 Ma (time-scale of Berggren et al., 1995b , is ∼0.2 Ma on the time-scale of Baksi, 1993 ) and was completed before the end of the Messinian. This corrects previous views that the Salinity Crisis continued until the Early Pliocene. There is no evidence in the Sorbas Basin for brackish `Lago Mare' conditions, and the normal marine biotas that directly precede and follow drawdown rebut earlier suggestions of prolonged salinity effects.

""We demonstrate that the age of 43 ka obtained for the topmost calcrete layer in the Guadix-Baza remains the. only reliable numerical dating of the flat geomorphic surface that marks the end of the sedimentation in the basin. Consequently, the late Pleistocene to Holocene erosion rates derived from the incision of the present- . day drainage network into the flat geomorphic surface remain valid. The calcrete radiometric ages reported by . Díaz-Hernández and Julià (2012) in their comment are untenable due to the contamination with detrital 230Th (not corrected with the applied U\\\/Th technique) and the possible mix of textural elements with different ages (older inherited grains and newly formed grains). Díaz-Hernández and Julià also quote U\\\/Th ages for travertine terraces formed later than the calcrete layer. These ages lack internal consistency probably due to systematic contamination and\\\/or weathering of the samples. The archaeological ages reported by Díaz-Hernández and Julià are subjected to great uncertainties, but independently of the age assumed as most realistic, they are completely compatible with the age of 43 ka that we obtained for the topmost calcrete layer in the Guadix-Baza basin.""