The Andean orogenic front between 31.5°S and 32.5°S represents a structurally complex and seismically active transitional zone of the southern Central Andes, where thin-skinned deformation of the Precordillera range interacts with thick-skinned tectonics of the Sierras Pampeanas broken foreland ranges. To date, a high-resolution three-dimensional structural model for this sector, which would allow a better understanding of the structural systems and their evolution, is lacking. To address this gap, we integrate 36 reprocessed 2D seismic lines, including, for the first time, N–S oriented profiles, together with gravity data, oil-well information, and detailed surface geological mapping. Interpretation of reprocessed seismic reflection lines depict a hybrid passive-roof structural architecture controlled by the uplift of a basement wedge, whose roof reaches depths of ~ 7 km and acts as the main detachment surface for an overlying thin-skinned thrust system. The basement wedge is emplaced beneath a thick Paleozoic-Neoproterozoic package (~4.5 km), reinterpreted as part of the Cuyania terrane carbonate platform, which was intensely deformed during pre-Andean tectonic events, possibly related to the Ordovician Ocloyic orogeny. The proposed kinematic model integrates at least eight evolutionary stages, ranging from Paleozoic deformation, through episodes of tilting, regional erosion, and syntectonic sedimentation, to Neogene-Quaternary eastward and southward migration of deformation. The identification of deeply rooted inherited structures and their differential reactivation explain the geometry of the main active folds and thrusts, as well as the spatial and temporal distribution of shortening. The lateral continuity of basement ramps and the large potential rupture areas imply a high seismogenic potential, with the capability of generating earthquakes of Mw ≥ 7. This study provides new constraints on the pre-Andean and Andean tectonic evolution of the region and establishes a robust structural framework for seismogenic potential assessment in a densely populated sector of west-central Argentina.

Broken foreland basins develop in response to far-field compressional stresses from active margins, resulting in deep-seated intraplate contractional structures that fragment the original foreland basin. This study investigates the tectono-sedimentary evolution of the Bermejo Basin, the first recognized broken foreland basin in South America, situated between the Eastern Precordillera and Western Pampean Ranges. Through the reprocessing of seismic data and gravity analyses, we identify three main tectono-sedimentary stages: Stage 1 (Pre-Neogene), Stage 2 (19-4 Ma), and Stage 3 (4-2.5 Ma to Present). Stage 1 generated structures that were buried and subsequently reactivated during Stage 2. This latter stage marked a significant reconfiguration of the basin with progressive northward propagation of compressional structures and a major shift in basin polarity around 6-5 Ma. These stages correspond to varying configurations of the Andean subduction zone, with strong foreland compression linked to flat subduction. However, the mild initial compression of a key structure active since 19-17 Ma, as evidenced by syntectonic strata, suggests that the foreland remained responsive to compressional forces transmitted from the plate margin during episodes of normal subduction. Our findings underscore the previously unrecognized role of inherited (or pre-Andean) compression in the evolution of the Bermejo Basin and provide evidence for a hybrid deformation style affecting the Eastern Precordillera, impacting the western margin of this basin. This study emphasizes the need for updated regional kinematic models that account for the interplay of ancient and more recent tectonic processes in the Bermejo Basin. Finally, our observations indicate that inherited compressional structures, such as the Carboniferous-Permian faults and the early Miocene Alto del Jumeal Range, have played a significant role in guiding subsequent deformation and sedimentation within the Bermejo basin.

The Guayatayoc salt flat basin, located in the northern sector of the Argentine Puna region (Jujuy province), stands out as one of the most promising areas for in depth geophysical research, focused on brine exploration. This region is considered one of the primary areas hosting several economically important lithium brine deposits. These results were obtained using gravimetry, audio-magnetotelluric (AMT), electrical resistivity tomography (ERT), magnetometry, and refraction seismic techniques. The main objective was to characterize the subsurface properties to infer the presence of clastic and/or evaporitic facies potentially carrying brines, as well as to identify marginal aquifers zones or freshwater sources that contribute to recharge and analyze the structural controls of the basin.Two 2D geological models were developed, revealing a structurally segmented basin into high and low blocks, with three sub-basins delimited by Paleozoic-Cretaceous basement blocks uplifted by faults. A sedimentary unit with densities and electrical resistivity compatible with saturated sands and gravels, possibly carrying brackish water or clay-rich formation containing brines was modeled.This work represents one of the few published studies that integrate multiple geophysical methodologies for the characterization of a salt flat basin located in the Puna region of Argentina. The use of multiple geophysical techniques promotes best practices in geophysical exploration and responsible resource management. This methodology can be replicated in other saline regions within the Lithium Triangle.

Northwestern Argentina in the Andean retroarc zone hosts Paleozoic, Cretaceous–Paleogene rift, and Paleogene-Neogene foreland units, representing the main hydrocarbon potential of the Central Andes. This study focuses on the Lomas de Olmedo sub-basin, the eastern branch of the Cretaceous rift system, with structures oriented parallel to regional compressive stresses that acted during the Andean orogenic phase. The considerable thickness of the synorogenic sedimentary sequences in the depocenter obscures the underlying basement structure, which is the main focus of the present work.Gravity data were used to model the lithospheric structure of the sub-basin through two 2D density models constrained by seismic, density, and structural data. The cross-depocenter model reveals 31 km of crustal thinning, inherited from extensional periods, whereas seismological models show a more regional, off-axis thinning pattern that does not fit the gravimetric data. The model parallel to the depocenter axis characterizes synorogenic and pre-orogenic sequences, where three overlapping sedimentary cycles reach a total thickness of about 10 km.The sub-basin lies within a transitional zone between a broken foreland basin in the south and a typical flexural foreland basin in the north. The modelled synorogenic sequences display the typical morphology of a foreland basin. A 2D flexural model with moderate rigidity (Te: 5–10 km) successfully reproduces basin architecture. Low Te correlates with westward-retracted deep seismicity, consistent with interpreted crustal thinning and reduced deformation front migration. This suggests that inherited rift-related structures, oriented parallel to regional stresses, may have controlled the limited eastward advance of the deformation front.Post-rift foreland sequences exhibit doming in transverse depocenter seismic lines and gravity models, consistent with flexural model forebulge predictions, suggesting a contribution to Neogene doming. The foreland basin is better analyzed using 2D flexural models, since, depending on lithospheric rigidity, they may have influenced synorogenic foreland deposition, modifying the stress field.

The mining industry is shifting to underground operations to enhance sustainability and productivity, necessitating the construction of concrete pavements within tunnels. Traditional in-situ construction techniques are slow, adversely affecting mine productivity. As an alternative, the Accelerated Construction approach proposes the use of precast pavement slabs. However, the unique combination of precast pavements, atypical mining loads and specific support conditions cannot be analysed using traditional pavement design methods. To address the lack of a suitable design methodology, this paper presents structural analysis of precast underground mining pavements (UMP) using custom linear-elastic three-dimensional finite element method (3D-FEM) software. The study examines the impact of slab dimensions, dowel spacing and subgrade stiffness on slab stresses. Three key findings emerged: (1) Pavement stresses are highly concentrated near the tires, especially when considering the braking forces common in mining operations. (2) Random rock stiffness within the tunnel increases design stress without altering the pavements' overall response. (3) The construction process influences slab design due to flexural stress caused by lifting forces. Overall, this paper contributes to the state-of-the-art in pavement engineering by providing a more reliable structural design methodology that incorporate an Accelerated Construction approach.

Hybrid alkaline fly ash pastes (HAFAPs) aim to maximize the fly ash (FA) content to reduce environmental impact and cost. However, significant amounts of FAs are discarded because they have high SO4 content. These FAs have been described as stable in HAFAPs when sodium alkaline activators are used, but sulfate-based activators have not been studied. Therefore, this research assesses the effect of different activators on HAFAPs formulated with high SO4, evaluating compressive strength and sulfate resistance. The results showed that high-SO4 FAs demonstrated a higher strength than low-SO4 FAs, with sodium-based activators being more susceptible to the binder/activator ratio and presenting a lower strength in high-SO4 HAFAPs. On the other hand, sulfate-based activators presented a higher strength but were unstable to external sulfate attack. Therefore, even though high-SO4 FAs have been described as stable to internal sulfate attack when sodium activators are used, external sulfates severely affect the durability of HAFAPs, so they are not recommended as construction material.

Concrete is essential for most civil engineering applications, but its use faces pressing challenges to reduce CO2 emissions. These emissions are linked principally to the chains of cement production that calcinate limestones (CaCO3 -> CaO + CO2) for quicklime, hydrated lime, and clinker production. Electrochemical decarbonation is a novel technology with the potential to introduce synergistic strategies to mitigate CO2 emissions from this chemical reaction. However, its early incorporation in the current chains of cement and lime production requires evidence of the quality of materials produced by this technique under the broad conditions of the cement and lime industries worldwide. In this reproducibility study performed in Canada and Chile, multiple sources of limestone feedstock used for lime and cement production were subjected to an electrochemical decarbonation process to precipitate low-CO2 intermediary feedstock materials. The potential of the precipitate materials (PMs) as an intermediary for cement manufacturing and as a final hydrated lime product was assessed by contrasting the lime saturation factor, lime concentration, content of secondary oxides (MgO, K2O, and Na2O), and content of CO2 with those of their precursor limestones and the requirements established by the state of practice of these industries. Results showed that regardless of their origin, the obtained PMs mainly comprised calcium hydroxide [Ca(OH)(2) > 78.8% by mass], with increased lime concentration (CaO > 65.39%) and decreased other primary oxides (SiO2, Al2O3, and Fe2O3 < 1%) and carbon dioxide content (CO2 < 9.42% by mass). Several PMs had suitable chemical and physical characteristics to be considered directly for clinker and lime manufacturing, which is critical to the scalability of the electrochemical decarbonation process.

In this study, we delve into an in-depth analysis of crustal mobility within the broken foreland of the Southern Central Andes, specifically focusing on the proximal area between 31°S and 32°S. This region presently stands as one of the most dynamically evolving and seismically active zones in the extensive Andean retroarc area. To achieve our goal, we employed a multidisciplinary approach encompassing the analysis of gravity data and GNSS measurements. Here, we discuss previous GNSS data and present new measurements, collected from a high-precision geodetic network established along the proximal broken foreland at 31°S latitude. To enhance our findings, we complemented this data with measurements of temporal gravity variations, primarily of tectonic origin, and conducted geophysical modeling of basement structures in the foreland area. Our geophysical model of the upper crust unveiled that deformation is closely associated with basement structures marked by faulted blocks and transverse lineaments identified in previous surface studies. The GNSS data analysis revealed complex crustal mobility patterns that are not easily explained. In general, the integrated analysis highlights varied responses observed in vectors and gravitational changes across distinct crustal domains in the study area that seem to conform to the characteristics of a fragmented or broken foreland setting. This structural configuration allows, to a certain degree, independent movement of crustal blocks. However, it appears that a substantial portion of the fractured foreland exhibits a relatively cohesive behavior, serving as coherent domains that facilitate elastic deformation linked to the underlying deep structures beneath the Eastern Precordillera. Therefore, this study provides further insights into the crustal mobility of broken foreland systems, where far-field tectonic stress interacts with complex basement block structures and intermontane sedimentary depocenters. These findings are of paramount significance in the context of intraplate earthquakes in the Andean broken foreland near San Juan City.

The construction industry, responsible for 39% of global greenhouse gas emissions, faces an urgent need for decarbonization to meet Net Zero Emissions by 2050. Addressing this challenge in the context of issues like structural fragmentation and complex value chains requires innovative solutions and accelerated implementation. This special issue of the Revista Ingeniería de Construcción presents contributions from academics and practitioners across multiple countries, exploring critical decarbonization trends in the industry. Featured topics include low-carbon materials, recycling innovations, material design and performance, use of industrial by-products, and infrastructure quality assurance and preservation. The findings underscore the need for collaboration, innovation, and research to advance sustainable practices, aligning the construction sector with global decarbonization goals. This work invites stakeholders to contribute to transforming construction towards a more sustainable future.

A model for enabling the production of lower carbon cement paste is proposed in this research. The model is based on predicting the strength of cement pastes with partial replacement of wheat straw ash (WSA) and silica fume (SF), two major wastes of agricultural and industrial production. The model is set up based on response surface methodology and Box-Behnken design, and included a suite of mechanical tests with distinct replacements following a micro an meso characterization. The model shows capability for predicting strength of any cement paste, including partial substitution of WSA and/or SF at any combination level with excellent accuracy, which is verified with three validation mixtures demonstrating maximum errors of less than 6% at the three ages. The analysis of the response surface evidences that any cement replacement in the range of 0-20% WSA and above 5% SF allows the reduction of the carbon footprint by maximizing the incorporation of both wastes. The proposed model can be used by setting the required strength of cement paste and calculating the maximum possible replacement, which should contribute to making the construction industry more sustainable by utilizing local waste.

Conventional cement production is a major source of carbon dioxide emissions, which creates a significant environmental challenge. This research addresses the problem of how to reduce the carbon footprint of cement paste production using agricultural and industrial waste by-products, namely wheat straw ash (WSA) and silica fume (SF). Currently, accurate models that can predict the mechanical properties of cement pastes incorporating these waste materials are lacking. To fill this gap, our study proposes a model based on response surface methodology and Box-Behnken design, designed to predict the strength of cement pastes with partial substitutions of WSA and SF. Through mechanical and characterization tests, the model demonstrated high accuracy in predicting the strength of the pastes, validated with three mixes, which showed maximum errors of less than 6% at different ages (7, 28, and 56 days). Response surface analysis revealed that replacing cement with 0–20% WSA and more than 5% SF can effectively reduce the carbon footprint by maximizing waste incorporation. This model allows for the calculation of optimal cement substitution levels based on the required strength, thus promoting sustainability in the construction industry through the use of local waste/resources.

Limestone decarbonation to obtain CaO (calcium oxide) and produce cement is an industrial activity with enormous CO2 emissions (CaCO3(s)-> CaO(s) + CO2(g)), due to the intrinsic calcination reaction of CaCO3 (calcium carbonate), in addition to the use of fossil fuels. One of the most recent ideas to reduce CO2 emissions in this process has been the electrochemical decarbonation of limestone where Ca(OH)2 (calcium hydroxide) is obtained as an intermediate product that is then used as CaO precursor in clinker synthesis. This study shows the design of a low-cost electrochemical reactor and the optimization of the parameters to produce Ca(OH)2 with high purity and yield from the decarbonation processes of pure CaCO3 and limestone used in the cement industry. In addition, the remaining limestone sludge and electrolytic solutions were analyzed, and it was found that the sludge can be used as a correction material in clinker preparation, and it is also possible to reuse the electrolytic solution twice. Finally, the main finding is the proposal of a new clinker synthesis, which results in a cement with comparable characteristics to those of ordinary Portland cement, using Ca(OH)2 obtained from the electrochemical decarbonation of CaCO3, achieving a reduction in CO2 emissions of approximately 90% compared to the conventional method.

The Precordillera fold-thrust belt, situated within the Pampean flat-subduction segment (27 degrees-33 degrees S), is characterised by enigmatic transversal structures which extend and influence deformation patterns, the full extent of which is yet to be fully elucidated. The Northern Pie de Palo Lineament represents a key example, and has been proposed to play a pivotal role in the development and structural control of the Precordillera. In any case, this lineament has not been subjected to a comprehensive study, which has led to ongoing debate regarding its structural control, persistence, and morphology. This study was therefore focused on this structure, employing multiple geophysical methodologies, including aeromagnetic and gravimetric techniques. This approach enabled the first visualization of the full extension and fault zone of the North Pie de Palo Lineament, which crosses the entire Precordillera fold-thrust belt in a transverse direction. Consequently, it can be posited that this structure would have exerted a conditioning influence on the thermo-mechanical state of the Andean lithosphere, enabled the uplift of mafic bodies and thus influenced the Neogene deformation of the Precordillera fold and thrust belt. The confirmation and characterization of this major structure open new perspectives on the interaction of deepseated transversal structures with fold belts during the evolution of the southern central Andes.

Industrial waste management has increased in recent years and, at the same time, the production of more sustainable and high-performance concrete has become one of the most important challenges related to the built environment. To contribute to face the previously mentioned challenges, this paper presents an experimental study on the influence of copper slag (CS) as a supplementary cementitious material (SCM) on the physical and mechanical concrete performance at both short- and long-terms. The CS was incorporated to concrete using five increasing levels (0%, 10%, 20%, 30% and 50% vol.) as SCM and both fresh state (slump) and hardened state (compressive strength, indirect tensile strength, flexural strength, porosity and capillary suction) properties of concretes were evaluated. The results showed that the highest slump was achieved by the concrete mixture with 50% CS, reaching a 27% increment compared to the reference concrete (0% CS). In the hardened state, both average compressive and splitting tensile strength values monotonically decreased with increasing CS content at short ages (28 days). However, at 360 days, the 10% SC concrete mixture presented average compressive and splitting tensile strengths of 57MPa and 4.9MPa, respectively, reaching and exceeding the corresponding strength values of the reference concrete, respectively. In addition, the mixture with 10% CS obtained the highest average flexural strength, reaching a 3.2% and 3.5% increment compared to the reference mixture at 28 and 360 days, respectively, which might be attributed to the more angular shape of the CS particles compared to the cement particles. In terms of physical properties, voids and absorption values increased as the CS content increased, yet at 360 days of curing, the only concrete that presented higher values than the reference concrete was the mixture with 50% CS (increments of 5.6% and 5.4% for voids and absorption, respectively). In conclusion, this study showed the advantageous potential use of CS as SCM at low percentages (between 10 and 20%), especially in long term performance of concrete mixtures.

The rise in greenhouse gas emissions, particularly CO2, has significantly contributed to global warming, with the residential and commercial building sectors playing a key role. Improving building energy efficiency through enhanced insulation is a crucial strategy for reducing CO2 emissions. However, conventional insulation materials have a high embodied carbon footprint, which limits their effectiveness in mitigating climate change. Biocomposites have emerged as an eco-friendly alternative to conventional materials. Countries like Chile, with their abundant agricultural fibers, show significant potential for fabricating biocomposites. This paper identifies the most produced fibers in Chile, including eucalyptus bark, wheat straw, rice husk, corn stalks, and walnut shells, and explores their potential use in the creation of sustainable biocomposite insulation materials.

Offsite construction methods have shown many advantages over traditional construction techniques, especially related to efficiency and productivity during the construction phase. Nevertheless, offsite construction generally involves oversizing the internal structure of the modules due to the internal stresses produced during transport and lifting operations, producing an increase in material usage, direct cost, and carbon footprint. In developing countries, the direct cost of social housing is the most important factor determining the feasibility of construction. For this reason, oversizing the internal structure of the modules can play an important role in the adoption of a modern construction technique such as offsite construction systems. In order to solve this issue, a temporary reusable stiffener structure is proposed to allow an economical offsite construction system using a lightweight steel framing structure used in traditional methods. The reusable structure was designed using a finite element method, and the direct cost and carbon footprint of the structure were evaluated. The results show that the proposed construction strategy allows for a low cost and reduced environmental impact due to a lower usage of materials in the modules and the possibility of a circular economy approach to the reusable structure.

Electrochemical decarbonation (ED) of CaCO3 is a promising method to reduce CO2 emissions from limestone calcination for cement manufacturing. Most cement plants are located near accessible deposits of limestone; therefore, the feasibility of ED deployment depends on the efficiency of natural limestone decarbonation, which has variable CaCO3 content. Accordingly, this research compares the ED efficiency of different limestones (CaCO3 content between 84 % and 68 %) and the chemical and physical characteristics of precipitate materials (PM) obtained from this process. The obtained PMs were comprised mainly of Ca(OH)(2) (similar to 59 %) and had similar particle size distributions. At the same time, the efficiency of Ca(OH)(2) precipitation, energy consumption, and CaO recovery were comparable to the ED of a pure CaCO3 reagent (>99 %). The PMs were found to have higher CaO content and lower loss on ignition than the feedstock material, independent of the type of limestone, facilitating the future ED implementation in cement manufacturing.

The intermontane Iglesia Basin constitutes the northern Uspallata-Calingasta-Iglesia tectonic depression that holds the Pismanta geothermal field, genetically connected with the basin evolution and structure. Understanding the local structure associated with this geothermal field and linking this system to the regional tectonics is essential to characterize thermal water rising in this area. To address this issue, we carried out a field-based structural analysis and an examination of sedimentary outcrops at the Pismanta area. Also, we linked surface structural data to the subsurface basin structure by means of a previously interpreted seismic reflection line. Our integrated analysis reveals that the Pismanta geothermal field is located in an area of favorable lithology at the intersection of WNW- and NNE-trending thrust faults. These jointly developed a permeability anomaly zone at the Pismanta locality that allows hot underground water rising from deep sedimentary sequences. This observation explains why the thermal springs are only locally concentrated in the study area; a key aspect that was not taken into account in previous models for the Pismanta geothermal field. These results and the overall basin tectonic evolution allowed us to define a new and more complex structural geothermal play model at the Pismanta field.

The Iglesia basin is a-3.5 km thick depocenter that holds an outstanding record of the late Cenozoic tectose-dimentary evolution of the southern Central Andes. Previous studies have indicated an initial tectonic stage associated with NNE-striking basin-bounding faults, formed by extension in the Late Oligocene (?)-early Miocene, and a subsequent basin inversion stage in the middle-Late Miocene. We conducted a multi-disciplinary study that allowed us to unravel a conspicuous structural system orthogonal to the previous basin-bounding faults. The analysis of seismic reflection lines, satellite and local gravimetry, and field data allowed the recog-nition of WNW-striking thrust fault zones involving the basement and Cenozoic sedimentary cover of the Iglesia basin. Also, we document Pliocene growth strata in seismic reflection lines and intra-Pliocene thrust faults at the surface that inform the timing of transverse fault activity. Therefore, we propose new tectonic stage during the Pliocene associated with the onset of a transitory NNE-trending contractional stress field, which triggered the reactivation of inherited basement structures transverse to the main Andean strike. This indicates a transient shifting in the stress field at-5 Ma that we associate with a major upper-plate reconfiguration caused by the full development of the Pampean flat-slab and major plate coupling.