Linear Surface Features Research Articles

Optimizing the Performance of Nickel Electrocatalysts with Regular Arrays of Linear Ridge-like Features for Enhancing the Oxygen Evolution Reaction

The oxygen evolution reaction (OER) represents a major source of inefficiency in the production of green hydrogen via electrocatalytic water splitting. At high overpotentials relevant to industrial rates of gas production, bubbles can contribute substantially to these inefficiencies by inhibiting the mass transport of electrolyte and partially obstructing the electrochemically active surface area (Aecsa) of an electrode.1 Arrays of microscale features have been shown to improve the efficiency of gas evolving reactions, including the OER. The performance of electrodes modified with linear ridge-like surface features has been previously observed to increase with the spacing between the ridges with a separation of up to 200 µm, but it was not known whether this trend continues indefinitely.2 The present study utilizes rapid prototyping techniques, including microscope projection photolithography and electrodeposition, to determine whether an optimal ridge separation exists between 200 and 450 µm. At a relatively high overpotential of 1.8 V (vs Hg/HgO) in an alkaline electrolyte, the performance of these ridges was observed to increase up to a critical separation, after which the performance decreased to a level comparable to a planar electrode at a wider separation between the ridges. Chronoamperometry measurements indicated that ridges with this optimal spacing attained a current response nearly 3× that of a planar electrode when normalized to (Aecsa). A better understanding of the reasons for this observed trend was pursued using high speed imaging. Direct observations of bubble production on the surfaces of the electrodes provided a deeper understanding of how the distribution of gas bubbles on an electrode affects performance.

Development of complex patterns of anthropogenic uplift and subsidence in the Delaware Basin of West Texas and southeast New Mexico, USA

The Delaware Basin in west Texas and southeast New Mexico is now the largest global oil producing basin, averaging ∼400,000 m3 (∼2,500,000 barrels) per day in 2022. The shale-dominated strata targeted for production can co-produce 4–5 times more water than oil, necessitating disposal by injection of ∼1,400,000 m3 (∼8,700,000 barrels) of water per day in 2022. Through a comprehensive assimilation of regional Sentinel-1 satellite radar data and analysis of production and injection, we show how petroleum operations have caused the development of complex and accelerating patterns of surface deformation from 2015 through 2021. We observe uplift from reservoir swelling, subsidence from reservoir contraction, and the development of linear features that are indicative of faulting. Subsidence is predominantly caused by production, and an important finding of this study is that the magnitude of subsidence is linearly proportional to total production. Uplift is caused by pressurization from wastewater injection of shallow permeable strata. The patterns of uplift are complex and extend laterally well-beyond areas where injection was performed. Linear surface deformation features are observed throughout the Delaware Basin, and they are lengthening and densifying as uplift and subsidence accelerate. Many of the lineations can be linked to known strata-bounded faults and shallow seismicity in the southern Delaware Basin where they serve as permeable and anisotropic conduits for pore pressure migration. In the Northern Delaware Basin, co-seismic rupture is hosted along basement-rooted faults that may link to the linear surface features. Understanding these dynamic changes in Delaware Basin is a pressing concern for management of subsurface reservoirs and safeguarding the surface environment. Concerns include ongoing induced seismicity, hazard of drilling through over-pressured strata, maintenance of integrity for newer wellbores, mitigation of flows of brine and petroleum fluids at the surface of old wellbores, and management of the pore space resource for wastewater injection.

LineaMapper: A deep learning-powered tool for mapping linear surface features on Europa

As discontinuities of the smooth icy surface, linear surface features might be directly or indirectly linked to Europa’s subsurface ocean. Mapping and categorising Europa’s lineaments is a means of retrieving information that could be linked to their formation history. As of today, planetary mapping is mainly conducted manually, which is tedious and subject to human bias once data sets become large. Mapping is further complicated by the heterogeneous quality and coverage of the available image data.Here, we train LineaMapper, a convolutional neural network (Mask R-CNN), to conduct instance segmentation of the four main units of linear surface features on Europa: bands, double ridges, ridge complexes and undifferentiated lineae. LineaMapper is trained on the basis of 15 mosaics from the Galileo solid-state imager data, yielding 930 training tiles. With LineaMapper, we provide a new method that facilitates detailed mapping of lineaments in Galileo images. LineaMapper could be applied to data to be returned by the Europa Imaging System (EIS) onboard the Europa Clipper mission. We validate LineaMapper v1.0 on an independent test set. On this test set, LineaMapper shows an overall higher precision than recall. In other words, there are more non-detections of actual lineaments than there are false detections of lineaments. The model shows the most correct predictions for double ridges (highest precision), while the most complete detections happen for ridge complexes (highest recall), compared with the ground truth. In some cases, LineaMapper preserves the cross-cutting relationships. The biggest strength of LineaMapper lies in its speed and tunable output. In the future, LineaMapper can be retrained, fine tuned and applied to similar looking features, for example wrinkle ridges on Venus, ridges on other planets and moons or even dust devil tracks on Mars.

Automatic lineaments detection using radar and optical data with an emphasis on geologic and tectonic implications: a case study of Kabul Block, eastern Afghanistan

The earth’s surface linear features, expressing geological lineaments, play a key role in identifying hydrothermal alteration and mineralization zones, as well as in understanding tectonic settings of a region. The objective of this investigation is to utilize a method for extracting lineaments automatically, which will be integrated and applied to identify geological-based lineaments by making use of remote sensing data. The study will further examine the structural pattern and temporal-spatial evolution of the lineaments and establish their connection with the primary active faults present in the Kabul Block. Multi-sensor data from radar (DEM (Digital Elevation Model)-5m, Sentinel-1B GRD (Ground Range Detected)) and optical sensors (Sentinel-2 MSI (Multispectral Instrument) and ASTER) were processed using spatial and spectral filters before automatic lineament extraction. LINE-module algorithm was applied to various illuminated hill-shades of DEM-5m, filtered HH (Horizonal-Horizonal) and VH (Vertical-Horizontal) of Sentinel-1GRD and PC1 (Principle Component) of Sentinel-2A MSI, and ASTER data to detect linear surface features. Extensive testing was conducted to verify the accuracy of extracted lineaments and to exclude any artificial lineaments in the study area. The radar and optical data results were compared while taking into consideration the geological and tectonic settings of the study area to select the most appropriate extracted lineaments. The DEM-5m and Sentinel-1B GRD showed the best result for identifying lineaments, and these were found to be highly correlated with previously available data in the Kabul Block. The final results of DEM-5m and Sentinel-1B GRD were further analyzed. The extracted lineaments were found to trend predominantly in a NW-SE and NE-SW directions, which is consistent with the results of other data. Temporal evolution and spatial distribution reveal that a high density of the lineaments is associated with Paleogene and Quaternary formations, while a low density is observed in Proterozoic, Paleozoic, and Mesozoic formations. The west and southwest edges of the Kabul Block are controlled by compressive stress trending NNW-SSE, while the north and southeast margins are influenced by NE-SW and ∼ N-S trending compressive stress.

The Removal of Meat Exudate and Escherichia coli from Stainless Steel and Titanium Surfaces with Irregular and Regular Linear Topographies.

Bacterial retention and organic fouling on meat preparation surfaces can be influenced by several factors. Surfaces with linear topographies and defined chemistries were used to determine how the orientation of the surface features affected cleaning efficacy. Fine polished (irregular linear) stainless steel (FPSS), titanium coated fine polished (irregular linear) stainless steel (TiFP), and topographically regular, linear titanium coated surfaces (RG) were fouled with Escherichia coli mixed with a meat exudate (which was utilised as a conditioning film). Surfaces were cleaned along or perpendicular to the linear features for one, five, or ten wipes. The bacteria were most easily removed from the titanium coated and regular featured surfaces. The direction of cleaning (along or perpendicular to the surface features) did not influence the amount of bacteria retained, but meat extract was more easily removed from the surfaces when cleaned in the direction along the linear surface features. Following ten cleans, there was no significant difference in the amount of cells or meat exudate retained on the surfaces cleaned in either direction. This study demonstrated that for the E. coli cells, the TiFP and RG surfaces were easiest to clean. However, the direction of the clean was important for the removal of the meat exudate from the surfaces.

Heritage documentation using laser scanner and photogrammetry. The case study of Qasr Al-Abidit, Jordan

The article describes a hybrid approach combining photogrammetry and laser scanning for 3D documentation of Qasr Al-Abidit palace; a rare example of Hellenistic architecture in Jordan. During data collection the information on edges and linear surface features is based on the analysis of images, whereas information on object geometry is provided from the laser data. By the combination of both data sources, the shape of 3D features can be determined in a flexible and accurate way and serve as an efficient tool for the identification of the nature, extent and severity of the façade deterioration.

Coseismic deformation and source model of the 12 November 2017 MW 7.3 Kermanshah Earthquake (Iran–Iraq border) investigated through DInSAR measurements

ABSTRACTA large earthquake with a magnitude of MW 7.3 struck the border of Iran and Iraq at the province of Kermanshah, Iran. In our study, coseismic deformation and source model of the 12 November 2017 Kermanshah Earthquake are investigated using ALOS-2 ScanSAR and Sentinel-1A/B TOPSAR Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques. Geodetic inversion has been performed to constrain source parameters and invert slip distribution on the fault plane. The optimised source model from joint inversion shows a blind reverse fault with a relatively large right-lateral component, striking 353.5° NNW-SSE and dipping 16.3° NE. The maximum slip is up to 3.8 m at 12–14 km depth and the inferred seismic moment is 1.01 × 1020 Nm, corresponding to MW 7.3, consistent with seismological solutions. The high-resolution optical images from SuperView-1 satellite suggest that most of the linear surface features mapped by DInSAR measurements are landslides or surface cracks triggered by the earthquake. Coulomb stress changes on the source fault indicating consistency between aftershock distribution and high loaded stress zones. Based on the stress change on neighbouring active faults around this area, the Kermanshah Earthquake has brought two segments of the Zagros Mountain Front Fault (MFF), MFF-1 and MFF-2, 0.5–3.1 MPa and 0.5–1.96 MPa closer to failure, respectively, suggesting the risk of future earthquakes. Recent major aftershocks (MW≥ 5.0) could probably ease the seismic hazard on MFF-2, but the risk of earthquakes on MFF-2 is still increasing.

Extraction of lineaments from different azimuth angles using geospatial techniques: a case study of Pravara basin, Maharashtra, India

Lineaments are the linear or curvilinear geological surface features which reflect the tectonic history, groundwater potential, oil, and mineral resource availability of a given area. In view of the importance of lineaments, the present study is carried out to understand the spatial distribution, orientation, density, and the influence of lineaments on drainage network. The study focuses on the extraction of lineaments in Pravara basin, Maharashtra, by using Cartosat Digital Elevation Model (CartoDEM). The lineaments are extracted and analyzed in ArcGIS and Rockworks software, respectively. Comparative analysis is performed on eight different lineament outputs which are extracted from various azimuth angles to prepare one final lineament map of the study area. Total number of lineaments found in the study area is 709 with the length of 1194.77 km. The western part of the Pravara basin shows higher lineament density as compared to the central and eastern part. Therefore, these areas might be affected by higher structural deformation. Also, this area might have higher groundwater infiltration potential due to the higher density of lineaments as they work as the structural weaknesses and influence the water to infiltrate in sub-surface region. The study has shown that the predominant orientation of lineaments trending to NNW-SSE. About 10% of the total stream length is found to have the influence of lineaments on the drainage network. More control of lineaments is observed in the source region of the drainage, where mostly first-order streams are found. Apart from the significant findings, this study has been generated a detailed structural information over the study area and the output could be applied for future planning and management of the water resources, tectonic evolution, and in other fields of geosciences.

Effects of laser polarization and linear surface features on nanoparticle synthesis during laser ablation in liquids

We elucidate non-isotropic interactions present during laser ablation of ridged surface features under linearly-polarized light and their effect on nanoparticle synthesis via the laser ablation in liquid method. A relationship between the relative polarization/ridge orientation and ablation processes was established by measuring cavitation bubble kinetics, examining the morphology of the ablated surface, and evaluating nanoparticle size distribution. Anisotropic behavior was observed, and this is attributed to selective heating of linear surface structures as confirmed with rigorous coupled-wave analysis. When the incident electric field is aligned parallel to the linear ridges on the target surface, the resulting nanoparticle distributions are much more monodisperse. This phenomenon has a strong influence in the polydispersity and batch-to-batch reproducibility in laser ablation in liquid.

Age determination of linear surface features using the Buffered Crater Counting approach – Case studies of the Sirenum and Fortuna Fossae graben systems on Mars

Buffered Crater Counting (BCC) offers a possibility to determine ages of linear/curvilinear surface features that provide no or only very limited surface areas for the conventional crater counting approach. In this study we applied the BCC analysis to two tectonic fault systems, Fortuna Fossae and a subsection of Sirenum Fossae. We compared BCC results with age estimates derived from conventional crater counting on the surrounding geologic units and investigated to what extent crater ejecta blankets can be used for determining the stratigraphic placement of craters pre- or post-dating the formation of linear features. Furthermore, we introduce a new functionality of the CraterTools software for ArcGIS which allows for a user-friendly semi-automatic application of the otherwise time-consuming procedure of BCC analysis. The software provides the resulting crater size-frequency data in a standard format, which can be read and analyzed in the CraterStats analysis software.Our case studies showed that the BCC approach provides equivalent or even more precise age results compared to the conventional stratigraphic approach. Here, we found that the investigated section of Sirenum Fossae is younger than previously thought. The derived formation age from the BCC analysis is 3.44-0.25+0.1Ga which corresponds to Late instead of Early Hesperian. Fortuna Fossae formed shortly after the emplacement of its now-fractured geologic host unit (Late Hesperian). Ages derived from BCC analysis vary between 3.53-0.11+0.06Ga and 3.50-0.11+0.07Ga. Furthermore, we recommend the use of crater ejecta blankets to position them in the stratigraphic sequence in order to improve crater statistics. However, the accuracy of the results depends on the extent and preservation state of the continuous ejecta blankets in the region of interest. Thus, the applied buffer width has to be chosen carefully according to investigated crater sizes and local observations.

Modelling of Kealey Ice Rise, Antarctica, reveals stable ice-flow conditions in East Ellsworth Land over millennia

AbstractFlow at ice divides, their shape, size and internal structure depend not only on local conditions, but also on the flow regimes and past histories of the surrounding ice masses. Here we use field data from Kealey Ice Rise, Ellsworth Land, West Antarctica, in combination with flow modelling to investigate any possible signs of transients in the flow of the surrounding ice masses. Kealey Ice Rise shows linear surface features running parallel to its ridge in satellite imagery and a conspicuous layering in the ground-penetrating radar data known as double-peaked Raymond bumps. Through numerical modelling, by using an anisotropic full-Stokes thermomechanical flow solver, we analyse the evolution of Kealey Ice Rise and the timescales involved. We conclude that the features observed in the stratigraphy of Kealey Ice Rise require at least 3 ka of near-stationary flow conditions. However, we cannot exclude the possibility of a recent flow reorganization in the last century. We stress that the signs of stationary flow in radar stratigraphy observed in Kealey Ice Rise have been observed in other ice divides in the East Ellsworth Land area, suggesting stationary flow conditions over a millennial timescale in the region.

Tectonics on Iapetus: Despinning, respinning, or something completely different?

Saturn’s moon Iapetus is unique in that it has apparently despun while retaining a substantial equatorial bulge. Stresses arising from such a non-hydrostatic shape should in principle cause surface deformation (tectonics). As part of a search for such a tectonic signature, lineaments (linear surface features) on Iapetus were mapped on both its bright and dark hemispheres. Lineament orientations were then compared to model stress patterns predicted for spin-down from a rotation period of 16.5 h (or less) to its present synchronous period, and for a range of lithospheric thicknesses. Many lineaments are straight segments of crater rimwalls, which may be faults or joints reactivated during complex crater collapse. Most striking are several large troughs on the bright, trailing hemisphere. These troughs appear to be extensional and are distinctive on that hemisphere, because the interior floors and walls of the troughs contain dark material. Globally, no specific evidence of strike slip or thrust offsets are seen, but this could be due to the age and degraded nature of any such features. We find that observed lineament orientations do not correlate with predicted patterns due to despinning on either hemisphere (the equatorial ridge was specifically excluded from this analysis, and is considered separately). Modest evidence for preferred orientations ±40° from north could be construed as consistent with respinning, which is not necessarily far-fetched. Assuming the rigidity of unfractured ice, predicted maximum lithospheric differential stresses from despinning range from ∼1 MPa to ∼160 MPa for the elastic spheroid and thin lithosphere limits, respectively (although it is only for thicker elastic lithospheres that we expect a nonhydrostatic state to be maintained over geologic time against lithospheric failure). The tectonic signature of despinning may have been obscured over time because the surface of Iapetus is very ancient, Iapetus’ thick lithosphere may have inhibited the full tectonic expression of despinning, or both. Several prominent lineaments strike E–W, and are thus parallel to the equatorial ridge (though not physically close to it), but a tectonic or volcanic origin for the ridge is highly problematic.

Investigation into the microstructure evolution caused by nanoscratch-induced room temperature deformation in M-plane sapphire

Nanoscratch tests have been conducted at room temperature on ( 1 0 1 ¯ 0 ) M-plane sapphire under a ramp loading condition from 100 μN to 200 mN along a scratch length of 200 μm at a scratch velocity of 1 μm s −1 using a Berkovich nanoindenter XPS system in scratch mode. Plastic deformation features, including short shaving scratch debris, linear surface features along the scratch groove, pile-up, and fish-bone features, indicating a stick–slip mechanism, and brittle deformation features, i.e. microcracking, chipping and tearing, were observed by optical, scanning electron, and atomic force microscopy. Applying the focused ion beam (FIB) technique, site-specific cross-sectional transmission electron microscopy further revealed nanoscratch-induced deformation behavior. Basal twinning was observed in the region below the scratch. The evolution of plastic deformation mechanisms can be summarized as lattice disorder, dislocation loops, stacking faults, dislocation glide and then basal twin formation. The observed features were rationalized using elastic and residual stress field calculations.

Exaggerated grain growth in bixbyite via fast diffusion along planar defects

AbstractNaturally occurring bixbyite single crystals from the Maynard claim at Thomas Mountain Range in Utah, USA, show pronounced grain growth, when compared to bixbyite crystals from other locations in close vicinity. These enlarged single crystals reveal characteristic linear surface features, which were initially interpreted as twin boundaries. HRTEM studies in conjunction with EDS analysis and electron diffraction, however, confirmed that these features originate from thin interlayers of braunite, Mn7SiO12, epitaxially grown within the host crystal. A model for the observed exaggerated grain growth is presented, which is based on the assumption that fast diffusion occurs along the braunite/bixbyite phase boundaries in three dimensions and, more importantly, promote nucleation at surface edges. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Initial stages of contact-induced plasticity in sapphire. I. Surface traces of slip and twinning

The present study focuses on the effects of surface orientation on the peculiarities of the earliest stages of nanoindentation-induced plasticity in sapphire (Al2O3) single crystal surfaces. The previous theoretical analyses do not account for all the experimentally observed trends. Additional considerations are required to bridge the gap between experimental results and theoretical predictions. Of key importance are accounting for the sense of twinning shear, the multiplicity of slip and twinning systems involved and an appropriate criterion for the transition from elastic to elastic-plastic regime. The present study supplements a continuum-based stress analysis with the above considerations and compares the resulting theoretical predictions with the experimental results for basal [C, (0001)], rhombohedral [R,(1102)] and prism [A,(1210) and M,(1010)] surfaces. Surface patterns of slip and twining are scrutinized in Part I. Previously unexplained features justified by the results obtained by the present authors include the distribution of the linear surface features ascribed to twinning and the symmetry of indentation pile-up. Part II focuses on the mechanisms of the transition between the elastic and elastic–plastic regimes.

Nanoindentation and Microindentation of CuAlNi Shape Memory Alloy

Nanoindentation and microindentation studies were conducted within individual grains of a CuAlNi shape memory alloy. Linear surface features were observed near the indentations after unloading, many of which were responsive to heating. Crystallographic orientation information was obtained from electron backscattering diffraction in order to compare the orientation of observed surface features to predicted austenite–martensite interfaces, slip planes, and possible fracture planes in this alloy. Most of the features observed can be attributed to austenite–martensite interfaces, which remain in the material after unloading due to the constraints of the plastic deformation created by indentation. Due to the temperature dependence of the transformation stress in shape memory alloys, these stress-induced martensites are observed to diminish with heating and to reappear with cooling. Plastic deformation is observed in the form of pile-up near the indentation.

Evaluating the potential of high‐resolution airborne LiDAR data in glaciology

We present the results of an investigation into the capabilities of high‐resolution airborne Light Detection And Ranging (LiDAR) for the study of a small glacier in Svalbard. The data are shown to be capable of producing a digital elevation model (DEM) with a horizontal resolution of 1–2 m and a vertical resolution of 5–15 cm. This degree of resolution is suitable for mass‐balance estimation using repeat data on an annual or semi‐annual basis, but it is also reveals linear surface features such as meltwater channels and crevasses. These have potential for tracking in repeat imagery to deduce the surface flow of the glacier. The intensity of the returned LiDAR pulse can also be used to discriminate snow‐covered parts of the glacier from bare ice.

Highly localized acoustic emission monitoring of nanoscale indentation contacts

This study evaluated a novel approach for acoustic emission (AE) monitoring of nanoindentation. The technique utilizes a miniature AE sensor integrated into a calibrated diamond indenter tip on a commercial nanoindentation system. The evaluation focused on the yield -point phenomenon in W (100); MgO (100); and sapphire C (0001); R (1012); A (1210); and M (1010) single-crystal surfaces. The minimum amount of elastic energy release sufficient to produce AE signal detectable with the indenter tip sensor was nearly two orders of magnitude lower than the minimum energy level required for conventional AE sensors. Wave forms detected with the indenter tip sensor were independent of sample size. A linear relationship between released elastic energies and the corresponding AE energies was observed for all three evaluated materials. The scaling coefficient of the linear relationship was independent of indenter tip size/shape and indentation depth. The differences between the mechanisms of the initial stages of plasticity for the various crystallographic orientations of sapphire were reflected in the following aspects of AE activity: detection of a specific type of AE wave form that correlated to the presence of linear surface features near the indentation sites; AE signal associated with the yield point, consisting either of one or two distinct wave forms; and presence or absence of AE signals after the yield point. The possibility of plasticity onset in sapphire involving both slip and twinning is discussed.

Acoustic Emission Monitoring of Nanoindentation-Induced Slip and Twinning in Sapphire

ABSTRACTMonitoring with an Acoustic Emission (AE) sensor integrated into an indenter tip was utilized for the evaluation of the earliest stages of indentation-induced plasticity in sapphire single crystal. The evaluated surfaces included basal (C), rhombohedral (R) and two different prismatic orientations (A and M). The differences between the mechanisms of the initial stages of plasticity for the various crystallographic orientations were reflected in the following aspects of AE activity: detection of a specific type of AE waveform that correlated to the presence of linear surface features near the indentation impressions; AE signal associated with the yield point, consisting either of one or two distinct waveforms; and presence or absence of AE signals after the yield point. Moreover, analysis of AE activity revealed loading rate effects on the yield point mechanism for the M plane. The possibility of plasticity onset mechanisms involving both slip and twinning is discussed.

Spirals on the sea

Spiral eddies were first seen in the sun glitter on the Apollo Mission 30 years ago; they have since been recorded on SAR missions and in the infrared. The spirals are globally distributed, 10-25 km in size and overwhelmingly cyclonic. They have not been explained. Under light winds favorable to visualization, linear surface features with high surfactant density and low surface roughness are of common occurrence. We have proposed that frontal formations concentrate the ambient shear and prevailing surfactants. Horizontal shear instabilities ensue when the shear becomes comparable to the coriolis frequency. The resulting vortices wind the liner features into spirals. The hypothesis needs to be tested by prolonged measurements and surface truth. Spiral eddies are a manifestation of a sub-mesoscale oceanography associated with upper ocean stirring; dimensional considerations suggest a horizontal diffusivity of order 103 m2 s-1.