Flow In Opposite Direction Research Articles

Purification free N-glycan analysis by capillary zone electrophoresis: Hunt for the lost glycans

Capillary gel electrophoresis is a widely used method for rapid separation of fluorophore labeled carbohydrates. Even though, many publications conferred about this popular technique, no report yet investigated the possible sample losses during the purification process of the fluorophore labeling reaction mixture. In the present work, normal polarity capillary zone electrophoresis separation mode was applied to take advantage of the opposite migration directions of the electroosmotic flow and the negatively charged sample components using Tris-hexanoic acid running buffer at basic pH. For purification free oligosaccharide analysis, the separation parameters were designed in such a way that the triple charged labeling reagent of aminopyrenetrisulfonate (APTS) could not enter the separation capillary in contrary to the labeled sample components of interest, therefore, the APTS did not have to be removed before analysis. The method was used to show electrophoretic profile differences possibly caused by the cleanup process that was immediately apparent by comparing the electropherograms of the purified and non-purified APTS labeled maltooligosaccharides. Furthermore, qualitative and quantitative N-glycosylation profile alterations were revealed during CZE separation of the fluorophore labeling reaction mixtures before and after purification along with the analysis of the consecutively used washing solutions for the well characterized standard glycoproteins of IgG, ribonuclease B and fetuin.

Graphene oxide partially exfoliated from carbon cloth: A new Paradigm of photocathode for Solar–Driven photoelectrochemistry

A critical factor limiting the photoelectrocatalytic reaction rate over semiconductors is severe photogenerated charge–carrier recombination, which is well–circumvented in this study by using graphene oxide (GO) partially exfoliated from carbon cloth (CC) as the photoelectrode. A kinetic model is proposed for the first time to rationalize the outstanding photoelectrochemical activity of GO/CC by accounting for the photoexcited charge carrier generation induced by harvesting of broadband sunlight mostly by GO. The photogenerated electron–hole pairs are thereby close to the GO/CC–electrolyte liquid junction and are rectified by surface band bending to flow in opposite directions. The charge recombination is hence largely suppressed and further quenched considering the high–lying conduction band extremum of GO, which favors injection of the photoexcited electrons into the electrolyte. As an important result of efficient charge separation, the photogenerated charge carriers relax mostly via the reaction with H2O2 in the electrolyte, as evidenced by the steady–state photocurrent density of GO/CC depending linearly on the light intensity and by the transient time constant of the time–resolved photocurrent response of GO/CC to chopped solar irradiation being primarily dictated by the diffusion and dissociative adsorption rate of H2O2 on GO/CC.

Numerical study and performance analyses of counter flow minichannel heat sink with slots on ribs

Various minichannel heat sinks are developed to cope with the increasing demand for thermal dissipation of electronic equipment. However, with the rapid development of microelectronics technology, temperature uniformity has gradually become a thorny problem needing more attention. Counter flow minichannel heat sinks with slots on ribs (CSF) were designed to enhance heat transfer and improve temperature uniformity. A 3D conjugated heat transfer model was developed in laminar flow regime, water has been selected as the working fluid, the constant heat flux was applied on the bottom surface of minichannel heat sinks. The counter flow minichannel heat sinks with slots on ribs not only possess higher heat transfer capacity, but also have better temperature uniformity. The average Nusselt number maximum increases to 2.01 times and the maximum temperature of bottom surface reduces 14.6 K for counter flow minichannel heat sink with five slots on ribs (CSF5) compared with parallel flow minichannel heat sink at Reynolds numberRe = 904. The temperature standard deviation of bottom surface maximum reduces 4.3 K for CSF3 minichannel heat sink atRe = 904. The effect mechanism of setting slots on ribs on the performance of counter flow minichannel heat sink was analyzed, it can be attributed to (i) interrupting and re-developing thermal boundary layer, and (ii) heat transfer between adjacent channels in which working fluid flows in opposite directions. Due to more uniform temperature of bottom surface and better heat transfer performance, the novel minichannel heat sink has potential application for thermal dissipation of electronic equipment.

3D numerical simulation of the separation zone at the channel-pipe junction.

At the confluence zone, the separation zone affects the flow, pollutant transport, and damages the bed and sidewalls of the channel. In this research, the geometric characteristics of the separation zone and the tailwater effect at the 90° channel-pipe junction are investigated using experiments and numerical simulations. These characteristics are different from the previous study in the channel or river junctions. (1) The separation zone is not attached to the sidewall of the channel. The shape of the separation zone is close to an ellipse but there is depression at the inside of the separation zone. (2) There is a pair of helical cells with opposite flow directions near the sidewall, which affects the shape of the separation zone and results in the differences. (3) The volume of the separation zone is proportional to the discharge ratio and the water-surface height. Furthermore, it's found that the momentum ratio is the basic reason affecting the volume of the separation zone. (4) The tailwater effect is affected by the discharge ratio and the water-surface height. And there is a significant positive correlation between the volume of separation zone and tailwater effect.

Numerical modeling on nuclide transport around a nuclear waste repository under coupled thermo-hydro-mechanical condition

Coupled thermo-hydro-mechanical (THM) processes may raise the uncertainty of nuclide transport behavior in long-term operation of nuclear waste repository. A far-field modeling framework on nuclide transport around a nuclear waste repository under coupled THM conditions was developed and verified. Base on conceptual models of high-level waste repository in fractured rocks, a three-dimensional repository model including a vertical fault and a horizontal fracture was built, and influence of coupled THM processes on nuclide transport is numerically investigated. Effects of repository depth, fracture inclination, and internal aperture heterogeneity were investigated using the developed model. The results show that the coupled THM processes significantly affect nuclide transport behavior, especially in the early stages of nuclide leaching. The thermal stress induced by heat release of nuclear waste causes the reduction in fracture aperture around the repository. The nuclide transport under THM conditions is retarded before 103 years than that under hydraulic condition. The deeper locations of the candidate repository exhibit the lower rate of nuclide transport. The inclined fracture induces opposite flow directions between two fractures, which causes the delaying of nuclide transport. Fractures with heterogeneous apertures have preferential flow paths, which results in early arrivals of nuclide transport than fractures with homogenous apertures.

Computational investigation of homogeneous-heterogeneous reactions in fluid with transport mechanisms: A finite element simulations approach

There are numerous applications in engineering and industry for homogeneous and heterogeneous chemical reactions in fluid regimes under the influence of nanoparticles and hybrid nanoparticles. This article models homogeneous and heterogeneous chemical reactions in the flow of polymer liquid (glycerin) containing Cu-Al2O3 in the presence of heat and mass transfer. The finite element method is used to quantitatively solve these models. A 76% increase in wall shear stress for the case of simultaneous dispersion of Cu and Al2O3 in comparison of only dispersion of Cu is noticed. Similarly, 44% increase in wall heat flux in noticed due to dispersion Cu and Al2O3 in comparison of dispersion of Cu only. The vortex parameter is responsible for a significant increase in the macro-motion of the fluid particles. Macro-motion gets more influence of micro motion than the influence of micro-motion on the macro-motion of Cu-Al2O3- polymer. To control momentum boundary layer thickness, reduce the diameter of the circular pipe. Magnetic force has the opposite direction of flow. Therefore, fluid motion is a decreasing function of magnetic field intensity. Further, the Lorentz force (magnetic force) for the case of Cu-Al2O3 - polymer is stronger than that for the case of Cu- polymer. Additionally, it can be seen that Cu-Al2O3- polymer experiences more Joule heating than Cu- polymer does. The micromotion is compromised when the curvature parameter is increased. As a result, convective transport slows down and the temperature of Cu- polymer and Cu-Al2O3 - polymers decreases. The result, the rate of conversion of electrical energy into heat speeds up intensity of magnetic field increase as and therefore, fluid temperature increases.

Estimating discharge coefficient of triangular free overfall using the GMDH technique

Abstract Free overfalls are hydraulic structures used in flood control, water supply, irrigation, and flow measurements. The hydraulic systems of free overfall depend on rectangular end shape. The studies that dealt with triangular crest are few and almost non-existent. In this study, a triangular end-shape design uses multiple linear regression (MLR) and group method of data handling (GMDH) methods for four models with six sub-models. Then, 24 scenarios were chosen and compared. The discharge coefficient (Cd) of a free overfall with a triangular terminal was predicted using experimental data. The triangular end edge shape increased crest length, the discharge coefficient, and discharge passing over free overfall. To this goal, 180 triangular free fall tests were performed. Data were collected for two triangular free overfalls with an opposite flow direction with three angles 600, 750, and 900. Results of Cd acquired using the two ways discussed above show that the algorithm GMDH outperforms the other method. Values for the GMDH approach mod46 testing variables: RMSE, MARE, SI, R2, and NSE are 6.08 × 10−17, 2.65 × 10−17, 6.00 × 10−17, 100.00%, and 1.00, respectively, while these values for MLR are 0.06332, 0.05970, 0.06624, 15.431%, and −3.0419, respectively. The GMDH technique shows the best results concerning MLR and then chooses the best four scenarios from 24 with a Cd percentage error not exceeding ±2%.

Investigate the full characteristic of a centrifugal pump-as-turbine (PAT) in turbine and reverse pump modes

Large centrifugal pumps can generate electricity in reverse, reducing the power supply pressure of the power grid. However, S region may occurs during the operation and regulation of the pump as a steam turbine (PAT). The S region can cause unstable unit startup, not only causing hydraulic system oscillation, but also accompanied by strong vibration and noise. Understanding the characteristic curve of the S region is of great significance for improving unit stability and efficiency. Previously, the main research object in S area was small generator units. This article conducted unsteady numerical simulation and experimental research on a large centrifugal pump. Analysed the internal flow rate, blade load, entropy generation, and pressure pulsation under three special operating conditions: the optimal operating condition, runaway operating condition, and braking operating condition in the S region. In addition, a comparative analysis was conducted on three pairs of operating conditions: S region turbine mode and reverse pump mode, with opposite flow direction, similar flow rate, and the same speed. Research has found that in the S region of large centrifugal pumps, the flow chaos in the turbine mode mainly occurs in the impeller section, and the maximum pressure occurs in the stationary blade section. The flow chaos under reverse pump operation mainly occurs in the stationary blade section, and the maximum pressure occurs in the impeller section.

Evidence of South American lithosphere mantle beneath the Chile mid-ocean ridge

Numerous geochemical studies on mid-ocean ridge basalts have established the presence of both compositional and lithological heterogeneities in the upper mantle. These studies have successfully constrained the composition and age of the chemical heterogeneities within the Earth's upper mantle. However, the origin of those heterogeneities remains highly debated. The Chile Mid-Ocean Ridge in the southeast Pacific Ocean, located far away from any hotspot, is colliding and subducting under the South America plate promoting the formation of a slab window. Comprehensive geochemical data (major, trace, volatile element contents and Sr, Nd, Hf and Pb isotope ratios) on Chile Ridge submarine glasses collected over the 1000 km ridge length demonstrate significant mantle compositional variability. Four main mantle components have been recognized: the typical Pacific MORB mantle, an enriched mantle (e.g., EM-1), a Subduction Modified mantle, and an anciently depleted mantle with unusually high Hf isotope ratios. Surprisingly, despite the large compositional variability, all glasses – including those with a subduction signature – have volatile-refractory element ratios within the range of the Pacific normal MORB. We propose that the Patagonia sub-continental lithospheric mantle, variably metasomatized since the Early Paleozoic, is eroded and incorporated into an asthenosphere with a south Atlantic MORB mantle composition that is flowing westward across the slab window from South America to the Chile Ridge. This scenario contrasts with a well-accepted geodynamic model that predicts the opposite direction of mantle flow. We speculate that the westward mantle flow across the slab window might be a counter-flow response to the opening of the Drake passage and the eastward movement of Pacific mantle since ∼30 Ma ago.

Inferring the Direction of Introgression Using Genomic Sequence Data.

Genomic data are informative about the history of species divergence and interspecific gene flow, including the direction, timing, and strength of gene flow. However, gene flow in opposite directions generates similar patterns in multilocus sequence data, such as reduced sequence divergence between the hybridizing species. As a result, inference of the direction of gene flow is challenging. Here, we investigate the information about the direction of gene flow present in genomic sequence data using likelihood-based methods under the multispecies-coalescent-with-introgression model. We analyze the case of two species, and use simulation to examine cases with three or four species. We find that it is easier to infer gene flow from a small population to a large one than in the opposite direction, and easier to infer inflow (gene flow from outgroup species to an ingroup species) than outflow (gene flow from an ingroup species to an outgroup species). It is also easier to infer gene flow if there is a longer time of separate evolution between the initial divergence and subsequent introgression. When introgression is assumed to occur in the wrong direction, the time of introgression tends to be correctly estimated and the Bayesian test of gene flow is often significant, while estimates of introgression probability can be even greater than the true probability. We analyze genomic sequences from Heliconius butterflies to demonstrate that typical genomic datasets are informative about the direction of interspecific gene flow, as well as its timing and strength.

Evaluation of vibratory shear-enhanced processing module-integrated three-dimensional printed spacers for enhanced wastewater ultrafiltration.

The article evaluates the effectiveness of two new designed module-integrated three-dimensional (3D) printed spacers in enhancing wastewater ultrafiltration efficiencies using vibratory shear-enhanced processing (VSEP). The study investigates the star-shaped spacer filled module channel (star spacer) and the column-shaped herringbone spacer filled module channel with the same position as the flow direction (column spacer) and with the opposite position as the flow direction (rev column spacer). It compares the VSEP module-integrated spacers with membrane module vibration (module vibration) and empty membrane module channel (control) configurations. The results show that the module integration of the 3D printed spacers can greatly improve the specific, average, and constant permeate fluxes and can contribute to reducing the total, reversible and irreversible resistance values, and specific energy consumption of the ultrafiltration membrane separation experiments. Overall, this study provides valuable insights into improving the performance of wastewater ultrafiltration systems and fouling mitigation through the module integration of 3D printed spacers and membrane module vibration. PRACTITIONER POINTS: Vibratory shear-enhanced processing (VSEP) ultrafiltration module-integrated 3D printed spacers were successfully fabricated and evaluated for improved wastewater treatment. Two spacer designs, a star-shaped and a column-shaped herringbone, were compared with an empty membrane module channel with and without vibration. Two configurations of the column-shaped spacer, in the same and reversed flow direction, were tested. Specific energy consumption was calculated and compared for all configurations. Significant improvements in ultrafiltration performance were observed with the use of spacers compared with an empty module channel, including enhanced permeate fluxes and reductions in both total and reversible, as well as irreversible, resistance.

Designing Large Two-Dimensional Arrays of Josephson Junctions for RF Magnetic Field Detection

This paper discusses improved design of two-dimensional (2D) arrays, potentially pushing the present state of the art of the high-Tc (and low-Tc) magnetic field detectors to a larger scale, i.e., higher sensitivity. We propose a two-plate geometry for parallel (and two-dimensional) arrays of Josephson junctions (JJs) for application in magnetic field detection. The arrays can be realized either by integration in the same substrate with a multilayer technology or on two different substrates. In the latter case, the substrates can be assembled in a flip-chip or piggyback configuration. A suggestion would be to divide a 2D array in two (equal) parts and to distribute each part on a different layer, one above the other. We model the current distribution in arrays connected in series so that the bias current flowing through the device flows in opposite direction in the layers. We demonstrate that this geometry greatly improves the uniformity of the bias current distribution across the width of the array, thereby restoring the critical current and, in principle, improving the Josephson array response. From the model, we conclude that the alignment of the arrays is not critical and that the realization of the devices requires only conventional techniques.

Modeling and Optimization of Hydraulic and Thermal Performance of a Tesla Valve Using a Numerical Method and Artificial Neural Network.

The Tesla valve is a non-moving check valve used in various industries to control fluid flow. It is a passive flow control device that does not require external power to operate. Due to its unique geometry, it causes more pressure drop in the reverse direction than in the forward direction. This device's optimal performance in heat transfer applications has led to the use of Tesla valve designs in heat sinks and heat exchangers. This study investigated a Tesla valve with unconventional geometry through numerical analysis. Two geometrical parameters and inlet velocity were selected as input variables. Also, the pressure drop ratio (PDR) and temperature difference ratio (TDR) parameters were chosen as the investigated responses. By leveraging numerical data, artificial neural networks were trained to construct precise prediction models for responses. The optimal designs of the Tesla valve for different conditions were then reported using the genetic algorithm method and prediction models. The results indicated that the coefficient of determination for both prediction models was above 0.99, demonstrating high accuracy. The most optimal PDR value was 4.581, indicating that the pressure drop in the reverse flow direction is 358.1% higher than in the forward flow direction. The best TDR response value was found to be 1.862.

Wavelength dependence of the surface photogalvanic effect in CuSe film

We demonstrate the changing sign of the surface photogalvanic effect current in a film consisting of CuSe nanocrystallites in an amorphous Se matrix in a wide spectral range. The longitudinal and transverse photocurrents were measured as functions of polarization state of the excitation beam and its incidence angle in the spectral range of 355–1064 nm. It was found that the longitudinal photocurrent flows in opposite directions at 532 and 725 nm (825 and 1064 nm) for the p-polarized (s-polarized) excitation beam. The longitudinal photocurrent excited by p-polarized light is much higher than that excited by s-polarized light. Both for the elliptically and linearly polarized excitation, the transverse photocurrent changes the sign between 532 and 725 nm. Such a reversal of photocurrent flow is explained by the photoexcitation of light and heavy holes bands, which have different momentum distribution of excited carriers. The data obtained provide deeper understanding of surface photogalvanic effect in nanocomposites and are of interest for optoelectronics.

Hybrid Technique for Setting Initial Water Saturation on Core Samples

Relative permeability and capillary pressure are important parameters in reservoir simulations because it helps in understanding and anticipating oil and/or gas production scenarios over the years. They are both obtained in a laboratory after establishing the required initial conditions. As a matter of fact, before measuring imbibition relative permeability and capillary pressure, it is recommended to set initial rock reservoir conditions by establishing appropriate initial water saturation (Swi) and by aging the core to restore the reservoir wettability. There are several conventional techniques to establish Swi. Viscous flooding is a fast technique, but it may create a non-uniform saturation profile and, in some cases, be inefficient in reaching low Swi targets. Centrifugation is a capillary-driven technique that is also very fast; however, the possibility of not desaturating the outlet face is a significant constraint. In both cases, reversing flow direction is generally performed to flatten the saturation profile; however, this phenomenon is poorly controlled. The application of capillary pressure by porous plate allows targeting a specific value of Swi and generates a uniform saturation profile; however, it is a very time-consuming method. In this paper, we present the Hybrid Drainage Technique (HDT), which couples viscous flooding and porous plate approaches, significantly reducing the experimental duration when setting Swi. Another advantage of the method is the possibility of setting a uniform saturation profile at the targeted Swi. A specific core holder, adapted to nuclear magnetic resonance (NMR) imaging and capable of performing both viscous flooding and porous plate testing without unloading the rock, was designed. Using this core holder enables performing aging and imbibition coreflood testing with no further manipulation of the core sample. Monitoring saturation profiles was made possible by using an NMR imaging setup. The method has been tested and validated on two outcrop samples from Bentheimer (sandstone) and Richemont (limestone), drastically reducing the experimental time of the primary drainage step in comparison to classical porous plate drainage but also leading to uniform water saturation profiles. The experiment duration is reduced, and it enables the realization of coreflooding; therefore, this technique may be used for larger samples classically used in relative permeability experiments. This approach is preferred as it provides faster and more reliable measurements of saturation.

Evolution of channel flow and Darcy’s law beyond the critical Reynolds number

For incompressible channel flow, there is a critical state, characterized by a critical Reynolds number Rec and a critical wavevector mc along the channel direction, beyond which the channel flow becomes unstable in the linear regime. In this work, we investigate the channel flow beyond the critical state and find the existence of a new fluctuating, quasi-stationary flow that comprises the laminar Poiseuille flow superposed with a counter-flow component, accompanied by vortices and anti-vortices. The net flow rate is reduced by ~ 15% from the linear, laminar regime. Our study is facilitated by the analytical solution of the linearized, incompressible, three-dimensional (3D) Navier–Stokes (NS) equation in the channel geometry, with the Navier boundary condition, alternatively denoted as the hydrodynamic modes (HMs). By using the HMs as the complete mathematical basis for expanding the velocity in the NS equation, the Rec is evaluated to 5-digit accuracy when compared to the well-known Orszag result, without invoking the standard Orr-Sommerfeld equation. Beyond Rec, the analytical solution is indispensable in offering physical insight to those features of the counter-flow component that differs from any of the pressure-driven channel flows. In particular, the counter flow is found to comprise multiple HMs, some with opposite flow direction, that can lead to a net boundary reaction force along the counter-flow direction. The latter is analyzed to be necessary for satisfying Newton’s law. Experimental verification of the predictions is discussed.Graphical

Linear analysis of the dynamic response of a riser subject to internal solitary waves

The flow field induced by internal solitary waves (ISWs) is peculiar wherein water motion occurs in the whole water depth, and the strong shear near the pycnocline can be generated due to the opposite flow direction between the upper and lower layers, which is a potential threat to marine risers. In this paper, the flow field of ISWs is obtained with the Korteweg-de Vries (KdV) equation for a two-layer fluid system. Then, a linear analysis is performed for the dynamic response of a riser with its two ends simply supported under the action of ISWs. The explicit expressions of the deflection and the moment of the riser are deduced based on the modal superposition method. The applicable conditions of the theoretical expressions are discussed. Through comparisons with the finite element simulations for nonlinear dynamic responses, it is proved that the theoretical expressions can roughly reveal the nonlinear dynamic response of risers under ISWs when the approximation for the linear analysis is relaxed to some extent.

Integration design optimization of self-thermal methanol steam reforming microreactor for hydrogen production

To enhance hydrogen production (HP) capability of self-thermal methanol steam reforming microreactor (MSRM), the integration design of MSRM is optimized from the aspects of the structure of combustion catalyst support (CCS), the number of CCS, the relative flow direction between HP reactant and combustion reactant, and the capability amplification mode of the microreactor. The results show that, when the microreactor uses the CCS with optimized structure in its front-end and integrates 2 CCSs with non-optimized structure in its back-end, meanwhile adopting the opposite flow direction between HP reactant and combustion reactant, as well as employing the number-amplified capability amplification method, it can obtain higher HP capability, whose CH3OH conversion, H2 quantity and CO selectivity are up to 100%, 2.519 mol/h and 4.43%, respectively, at the feed quantity of 48 mL/h methanol-water compound (fuel for HP) and 3.2 mL/min methanol (fuel for combustion).

Josephson diode based on conventional superconductors and a chiral quantum dot

We propose theoretically a Josephson diode consisting of the conventional superconductors with the plain $s$-wave pairing and a chiral quantum dot. When an external magnetic field is exerted on the quantum dot, the critical current of the Josephson structure is different for the opposite directions of current flow. The strong nonreciprocity can be obtained in a large area of the parameter space. The inversion and the on/off state of the nonreciprocity can be conveniently regulated by adjusting the direction of the external field. The dependencies of the nonreciprocal behaviors on the hopping amplitude, the magnitude of the magnetic field, and the energy level of the quantum dot are investigated in details using the Keldysh nonequilibrium Green's function formalism under the self-consistent procedure. The symmetric and the antisymmetric properties of the nonreciprocity are analyzed from symmetries satisfied by the superconductors. The proposed diode effect also applies to other chiral conductors as interlayer. Its formation has no restriction on the type of the current-phase difference relations. The generality and flexibility of our proposed diode effect provides more possibilities for the design of the dissipationless diode devices.

Tectonic framework of surface and blind structures from neotectonic and geophysical (gravimetry) analyses, Central Andes of Argentina

This work describes new evidence of N–S and oblique trending surface and blind structures in the La Cantera-Gualilán tectonic depression in the Central Precordillera, San Juan Province, Argentina. Two main N–S Quaternary thrusts cross longitudinally the valley located ∼60 km west of San Juan city (30° 50′- 31° 17′ S and 68° 55′- 69° 05′ W). One of them is located in the eastern piedmont of the Sierra de La Invernada (San Juan Fault) and the other in the western piedmont of the Sierra de La Cantera (La Cantera Fault System), although the northward continuation of this structure has not yet been confirmed.Besides, a smooth water divide or “portezuelo” controlled by an oblique transpressive structure (Divisadero Coba Rubia Fault) separates two N–S elongated river basins with opposite water flow directions. One of these is the Gualilán River, which flows from south to north, and the other corresponds to the La Cantera River, running from north to south.In the present work, we describe some new natural exposures and subtle geomorphological evidence of Quaternary structures identified in the Gualilán-La Cantera tectonic depression. We also use regional and local gravity data to analyze and interpret gravity anomalies related to these surface or blind active structures. Then, based on our geologic and geophysical interpretations, we infer the presence of several, buried cross-strike structures with NW and NE trends, one of them coincident with the drainage divide between the Gualilán and La Cantera opposite river basins, possibly related to the Coba Rubia Fault. Also, we suggest the northward continuation of the La Cantera Fault System (LCFS) as a buried structure in coincidence with the Gualilán River alluvial plain. In this sense, the gravity response of the basement and these river sub-basins shows a close relationship with the surface and subsurface structures. We propose that the oblique structures could represent pre-existing crustal fabrics reactivated during the Andean orogeny, segmenting the N–S Precordillera fold and thrust belt system. Finally, according to the analyzed neotectonic and gravimetric features, we consider the La Cantera-Gualilán Valley as a potentially seismogenic source in this intraplate portion of the Andean Precordillera, crossed by several N–S and oblique surficial and buried/blind active structures. These tectonic features could play a significant role in a regional seismic hazard assessment.