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We applied an interdisciplinary approach to analyze the late Quaternary activity of the Sava Fault in the Slovenian Southern Alps. The Sava Fault is an active strike-slip fault, and part of the Periadriatic Fault System that accommodated the convergence of Adria and Europe. It is one of the longest faults in the Southern Alps. Using high-resolution digital elevation models from lidar and photogrammetric surveys, we were able to overcome the challenges of assessing fault activity in a region with intense surface processes, dense vegetation, and relatively low fault slip rates. By integrating remote sensing analysis, geomorphological mapping, structural geological investigations, and near-surface geophysics (electrical resistivity tomography and ground penetrating radar), we were able to find subtle geomorphological indicators, detect near-surface deformation, and show distributed surface deformation and a complex fault pattern. Using optically stimulated luminescence dating, we tentatively estimated a slip rate of 1.8 ± 0.4 mm/a for the last 27 ka, which exceeds previous estimates and suggests temporal variability in fault behavior. Our study highlights the importance of modern high-resolution remote sensing techniques and interdisciplinary approaches in detecting tectonic deformation in relatively low-strain rate environments with intense surface processes. We show that slip rates can vary significantly depending on the studied time window. This is a critical piece of information since slip rates are a key input parameter for seismic hazard studies. [ABSTRACT FROM AUTHOR]

Abstract\nKEY POINTSUnderpinning almost every Paleozoic paleogeographic reconstruction and tectonic model of the Lachlan Orogen is the interpretation of the structural geology related to crustal collision and amalgamation. Bounding the eastern margin of the Lachlan Orogen is a north-trending corridor of Cambrian–Ordovician turbidites that in northeast Victoria are recognised as the Pinnak Sandstone or previously known as the Mallacoota Beds. This sequence contains an accretionary prism related early S* foliation, syn-sedimentary dykes, slump structures, early faults or décollements and early quartz veins. These indicate anisotropic compaction by fluid extraction in a shallow marine turbidite sequence that underwent localised deformation (D1), which can be attributed to the Benambran Orogeny (ca 450 Ma). There was a change in the rheological properties during the ensuing late Silurian D2 Bindian Orogeny (ca 420 Ma). This event produced north–south-trending upright, east-verging folds (F2) with a marked partitioning of strain between the different sedimentary units. Folds plunge south at ∼30°, are tight to isoclinal, with local collapsed hinges and limb thrusts. This D2 deformation along the paleo-Pacific margin involved dextral transpression and a southerly propagation of the deformation front. Superimposed on these structures is an east–west paleostress pattern and two episodes of faulting (D3 and D4). In the first, brittle strike-slip faults were accompanied by ductile folding related to east–west shortening during the Middle–Late Devonian Tabberabberan Orogeny (ca 385–370 Ma). These were accompanied by the emplacement of the Sandpatch Point Granite. The second episode (D4) of strike-slip faulting reactivated many of the earlier faults during further east–west shortening and was related to the Carboniferous Kanimblan Orogeny (ca 354–343 Ma). This is best seen close to the granite contact where the strong crystallised granite reinforced the contact metamorphosed greywacke sequence, inhibiting ductile deformation so that faults deformed in a brittle fashion.Eastern Australia was at a convergent plate boundary where a Middle–Late Ordovician turbiditic sequence was accreted to an accretionary prism.The Pinnak Sandstone contains a weak phyllosilicate alignment (S*), D1 faults and folds from localised deformation in the accretionary prism.The Silurian Bindian Orogeny produced upright east-verging, south-plunging F2 folds. Brittle faults overprint the Bindian tectonic features and are accompanied by minor folding, marking the transition into Middle Devonian and Carboniferous deformation and intrusive events.The kinematics and geometries associated with these deformation events reflect the changing tectonic regime along the paleo-Pacific margin of eastern Australia during east–west compression. [ABSTRACT FROM AUTHOR]

As the world's glaciers recede in response to a warming atmosphere, a change in the magnitude and frequency of related hazards is expected. Among the most destructive hazards are glacier lake outburst floods (GLOFs), and their future evolution is concerning for local populations and sustainable development policy. Central to this is a better understanding of triggers. There is a long‐standing assumption that earthquakes are a major GLOF trigger, and seismic activity is consistently included as a key hazard assessment criterion. Here, we provide the first empirical evidence that this assumption is largely incorrect. Focusing on the Tropical Andes, we show that, of 59 earthquakes (1900–2021) the effects of which intersect with known glacier lakes, only one has triggered GLOFs. We argue that, to help develop climate resilient protocols, the focus for future assessments should be on understanding other key GLOF drivers, such as thawing permafrost and underlying structural geology. Plain Language Summary: Climate change is increasing glacier melt in high mountains and increasing the size and number of glacial lakes. Over time, these lakes may drain catastrophically to generate glacier lake outburst floods (GLOFs), which can devastate downstream communities and destroy valuable infrastructure such as roads, bridges, and hydroelectric power facilities. As a result, many risk assessments have been carried out to understand what the triggers of GLOFs might be, in order to better predict their occurrence. One of the main triggers has been assumed to be earthquakes, but this association has not been properly tested. In this paper, we use earthquake and GLOF data from the Peruvian and Bolivian Andes to test this and find that there is little association between earthquakes and GLOFs. We conclude by arguing that focus needs to be on other GLOF triggers, and earthquake activity should be used as a secondary – not primary – indicator in GLOF susceptibility studies. Key Points: Glacier lake outburst floods (GLOFs) are a major risk concern, with earthquakes being commonly considered effective triggers in hazard assessmentsOf 59 earthquakes (1900–2021), the effects of which intersect lakes in the Tropical Andes, only one triggered GLOFsWe suggest that earthquake activity should be used as a secondary – not primary – susceptibility indicator for GLOFs [ABSTRACT FROM AUTHOR]

The Shangdan suture zone (SDZ) in the Qinling orogenic belt (QOB) is a key to understanding the East Asia tectonic evolution. The SDZ gives information about convergent processes between the North China Block (NCB) and South China Block (SCB). In the Late Mesozoic, several shear zones evolved along the SDZ boundary that helps us comprehend the collisional deformation between the NCB and SCB, which was neglected in previous studies. These shear zones play an essential role in the tectonic evolution of the East Asia continents. This study focuses on the deformation and geochronology of two shear zones distributed along the SDZ, identified in the Shaliangzi and Maanqiao areas. The shear sense indicators and kinematic vorticity numbers (0.54–0.90) suggest these shear zones have sinistral shear and sub-simple shear deformation kinematics. The quartz's dynamic recrystallization and c-axis fabric analysis in the Maanqiao shear zone (MSZ) revealed that the MSZ experienced deformation under green-schist facies conditions at ∼400–500 °C. The Shaliangzi shear zone deformed under amphibolite facies at ∼500–700 °C. The 40Ar/39Ar (muscovite-biotite) dating of samples provided a plateau age of 121–123 Ma. Together with previously published data, our results concluded that QOB was dominated by compressional tectonics during the Late Early Cretaceous. Moreover, we suggested that the Siberian Block moved back to the south and Lhasa-Qiantang-Indochina Block to the north, which promoted intra-continental compressional tectonics. [ABSTRACT FROM AUTHOR]

The topography of the Harlik Mountain has a strong impact on the formation of current arid climate in the Turpan-Hami Basin. However, it is still controversial if Harlik Mountain experienced significant exhumation during the Middle to Late Cenozoic according to the previous thermochronology studies. The features of the Oligocene to Miocene sediments in the foreland basin could provide productive information for resolving the debates. The peak ages of detrital apatite fission track analysis of the Oligocene–Miocene sandstone in the Turpan-Hami Basin are well comparable with the cooling age records of the Harlik Mountain rocks, indicating that the Oligocene–Miocene Taoshuyuanzi Formation in the basin was mostly derived from the Harlik Mountain. The stratigraphic sequence exhibits coarsening upward, reflecting that the source area was in a tectonically active period during the deposition process. Heavy mineral assemblages also suggest that the unstable minerals in the sediment increased significantly at the end of the deposition. Moreover, the proportion of apatite increased up-section, while the garnet content decreased significantly, indicating that the Carboniferous metamorphic rocks have been gradually eroded out and more intrusive rocks have been exposed to the surface. These observations suggest that the Harlik Mountain experienced exhumation during the Oligocene to Miocene, and the denudation depth afterward was probably less than 2.5 km according to the previously apatite (U-Th)/He data. The Oligocene–Miocene exhumation probably acted as one of the triggers for the heavy drought of the Turpan-Hami Basin during the Middle–Late Neogene. [ABSTRACT FROM AUTHOR]

Middle Eocene to early Oligocene intrusions, widespread in the Ruby Mountains– East Humboldt Range metamorphic core complex, Nevada, USA, provide insights into a major Paleogene magmatic episode and its relation to tectonism in the northeastern Great Basin. These intrusions, well-exposed in upper Lamoille Canyon, range in composition from gabbro to leucomonzogranite. They form small plutons, sheets, and dikes that intrude the metamorphic and granitic infrastructure of the core complex. Two types of Paleogene monzogranite were recognized. The first is exemplified by two of the larger intrusive bodies, the Snow Lake Peak and Castle Lake intrusions, which occur as sheet- like bodies near and at the structural base of metamorphosed Neoproterozoic and Cambrian Prospect Mountain Quartzite where it is inverted above Cambrian and Ordovician marble of Verdi Peak in the Lamoille Canyon nappe. Swarms of dikes are associated with these intrusions. U-Pb (zircon) ages range ca. 40– 33 Ma and typically display relatively simple and minor inheritance. The rocks have the lowest εHf (zircon) and εNd (whole rock) of any of the middle Cenozoic granites. The second type of monzogranite, Overlook type, typically occurs as thin, isolated dikes and leucosome- like bodies in Late Cretaceous granites of the infrastructure, with no obvious relationship to the large monzogranite bodies. Overlook- type monzogranite displays complex zircon inheritance, yields igneous ages ca. 37– 32 Ma, and has εHf (zircon) and εNd (whole rock) identical to those of Late Cretaceous granites in the core complex. These isotopic and field data indicate that Overlook- type monzogranite formed in situ through anatexis of host Cretaceous granites. A pervasive thermal event was required to stimulate this crustal melting. Gabbros from Lamoille Canyon and quartz diorite dated from 32 km away signal mantle- derived magmatism ca. 39– 37 Ma (U-Pb, zircon) was a driver of crustal melting and hybridization. Eocene 40Ar/39Ar apparent ages on hornblende and biotite are consistent with syn- to post- magmatic extensional exhumation and decompression. Thus, the core complex provides a window into trans- crustal magmatism and insight into how such magmatism affected the Nevadaplano orogenic plateau. This Paleogene thermal pulse, which may relate to removal of the Farallon slab by delamination of mantle lithosphere, involved partial melting of the upper mantle and transfer of magma and heat to the Nevadaplano crust. Lower- crustal melting of Archean(?) to Paleoproterozoic rocks resulted in Snow Lake Peak– type magmas, and middle- crustal melting of granite in the infrastructure yielded Overlook- type magmas. This crustal magmatism, as exemplified by the intrusions in the core complex, likely played a role in destabilizing the Nevadaplano and its later collapse during middle Miocene extension. The Paleogene intrusions and associated structural features also provide insight into the evolution of the core complex through either the buoyant upwelling of a melt- rich diapir (gneiss- dome model) or buoyant upwelling of the melt- rich middle crust synchronous with a west- rooted mylonitic shear zone (extensional shear- zone model). We favor a hybrid that incorporates both models. [ABSTRACT FROM AUTHOR]

In July 2023, Himachal Pradesh, India experienced heavy rainfall that led to numerous landslides and significant damage. The affected districts of Shimla, Kullu, and Mandi were the hardest hit, with 223 fatalities, 1300 road closures, and extensive property damage. Factors contributing to the landslides included the intense rainfall, the area's geology and topography, and human activities such as unplanned construction and deforestation. The damage assessment is still ongoing, but initial reports indicate thousands of landslides, loss of life, injuries, and destruction of homes. Further investigations are needed to understand the slope characteristics and develop effective emergency plans to mitigate future impacts. [Extracted from the article]

The relationship between rock-slope failure and glacier retreat is complex, and paraglacial failures often lack clearly identified triggers. To better understand the role of glacier retreat in rock-slope failures, we analysed the processes that led to the October 1967 Grewingk landslide in Kachemak Bay State Park on the Kenai Peninsula, Southcentral Alaska. The rock material collapsed onto the glacier toe and into its pro-glacial lake and produced a tsunami wave that swept the outwash plain. On the day of the failure, rainfall and snowmelt were well within normal ranges, and seismic records show no significant shaking. Three years prior to the 1967 failure, the slope withstood the second largest earthquake ever recorded (Great Alaskan earthquake, MW 9.2). We reassessed the volume of the failure by differencing pre- and post-digital terrain models and found a value of 20–24 × 106 m3, which is four times smaller than a previous estimate. The back analysis of the Grewingk landslide is based on remote sensing data and field measurements including aerial satellite image analysis, detailed surveying and understanding of the structural geology, a kinematic analysis, and runout modelling. Our research provides an example of a major paraglacial failure that lacks an obvious trigger and points to several geological factors and changing environmental conditions that likely promote such failures. This study further indicates that the Grewingk landslide, pre-conditioned by the geometry of faults and joints, may have reached a critical stability state due to internal processes and the potential combined effects of seismic activity and glacier retreat prior to the collapse. [ABSTRACT FROM AUTHOR]

Azizi, H., Daneshvar, N., Asahara, Y., Minami, M. & Anma, R. (2023). The generation of Eocene mafic dike swarms during the exhumation of a Core complex, Biarjmand area, NE Iran. Journal of Petrology 64 , 1–18 have attributed the E–W-oriented mafic dike swarm in the Biarjmand metamorphic core complex to an Eocene extensional event which is much younger than a previously suggested Late Jurassic–Early Cretaceous age. They proposed that the emplacement of these dikes occurred in a rapid extensional regime coeval with the exhumation of the core complex after gravitational instability in the Central Iran/Eurasia collision zone. I appreciate the opportunity this article provides to shed light on specific aspects of the Late Mesozoic–Early Cenozoic continental extension within the Eurasian sector of the Neotethys subduction system. However, I here bring to attention certain discrepancies within Azizi et al. 's publication. Specifically, the assignment of an Eocene age to the emplacement of the E–W-oriented dike swarm, even though purportedly supported by U–Pb zircon dating, appears to be at odds with field observations and previously published geochronological data. Furthermore, the article contains internal contradictions in its presentation of the core complex model for the study area. It is important to note that Malekpour-Alamdari, A., Axen, G. J., Heizler, M. T. & Hassanzadeh, J. (2017). Large-magnitude continental extension in the northeastern Iranian plateau: insight from K-feldspar 40Ar/39Ar thermochronology from the Shotor Kuh-Biarjmand metamorphic core complex. Geosphere 13 , 1207–1233 previously documented the geochronological-based metamorphic core complex model of the area. Regrettably, despite its direct relevance, these earlier works have not been acknowledged in Azizi et al. 's paper. In this comment, I outline the problems with the structural and regional geology, the zircon U–Pb age of the dike samples, the age of the dike swarm, and the geodynamic interpretations in Azizi et al. 's work. [ABSTRACT FROM AUTHOR]

This document provides a summary of various scientific articles and discoveries. It begins by discussing Japan's Moon lander, which successfully resumed operations after a rough landing. Australian geologists used plate tectonic modeling to understand an ice-age climate in Earth's history, while amateur paleontologists found well-preserved fossils in France that shed light on polar ecosystems. The document then highlights articles on Shap Granite production in the UK, Triassic vertebrate fossils in Antarctica, dental wear in dinosaurs, snake traces in South Africa, vulcanian bombs in Ecuador, and a salt diapir in Iran. These articles offer valuable insights into a range of scientific topics. [Extracted from the article]

A characteristic of the Pannonian Basin is its strong geothermal flow. Geothermal water is present in aquifers in the Miocene and Pliocene sediments of the Lendava, Murska Sobota, and Mura formations, as well as in pre-Neogene sedimentary rocks, at a depth of several 1000 s to several 100 s of meters. The water from the deep Miocene and Pliocene aquifers is mainly pumped for use in the spas of the region, which is separated by national borders. Pumping water from the aquifers lowers the hydraulic head of the water in the aquifers. The consequence of the drop in hydraulic head is a reduction in the yield of the aquifers, which has a negative impact on the neighboring wells. In order to prevent the effects of this influence—especially in the case of transboundary influences, as in our case—the construction of an additional well was proposed, through which the cooled water would be pumped back into the deep aquifer. For the specific case of the Terme Korovci project, which is located directly on the national border, a 3D structural model of the aquifer was created. The hydrogeological and thermal properties of the aquifer were determined on the basis of the lithological profile of the wells in the region, along with well logs and pumping tests. As detailed data on the thicknesses of the layers have not been available until now, we have envisaged several scenarios for different layer thicknesses. As will be evident from our data, in the case of a 10 m-thick layer, the temperature falls to below 70 °C in fewer than 6000 days, and this period extends with increasing thickness such that with a 200 m-thick layer, the period extends to well over 100,000 days. The findings are important because the potential investor requires at least 20 years of operation of the pumping–reinjection pair of wells. [ABSTRACT FROM AUTHOR]

The Earth's crust is exposed by tectonic processes and is not static over time. Modelling of the Earth's surface velocities is of utmost importance for research in geodesy, geophysics, structural geology, and other geosciences. It may support positioning, navigation, seismic risk, and volcano notification services, for example. Space geodetic techniques can be used to provide high-quality velocities in a network of geodetic sites. Velocity field modelling should, however, expand the velocities from a discrete set of points to any location in-between. This paper presents four new methods for the Earth's surface velocity interpolation. Contrary to the widely used approach dividing the velocity field to the horizontal and vertical components, a full 3D interpolation approach is proposed based on the Delaunay triangulation and the n-simplex interpolation. The use of a combination of all three components is advantageous for geophysical interpretation. The proposed interpolation approach is entirely local but enables global modelling, which does not suffer from map projection distortions and singularities at the poles. Various global and regional position/velocity datasets are used to evaluate the performance of the proposed velocity interpolation methods. The latter provide practically the same results when applied to regional velocity field modelling. However, the so-called continuous piecewise quasi-radial 3D velocity field interpolation method is recommended for its favourable properties. It introduces an ellipsoidal Earth model, appropriately considers vertical/up and horizontal velocity components, tends to radial symmetry, and provides continuity for the interpolated velocity components as well as for the estimated uncertainties. [ABSTRACT FROM AUTHOR]

The Tyennan Domain of western Tasmania is a structurally emplaced, complexly deformed lithotectonic sheet (allochthon). It comprises stacked, isoclinally folded slabs of allochthonous high-grade schist including garnet schist and quartzite, amphibolite and rare eclogite (uppermost unit), overlying low-grade pelite, overlying low-grade quartzite and platy quartzite (middle unit), overlying parautochthonous low-grade dolomitic pelite, quartzite and dolostone (lowermost unit). It is a product of Cambrian continental margin subduction, rebound and exhumation coupled with ophiolite obduction. Tyennan rocks were transported to maximum depths of ∼60–80 km sufficient to generate high-P metamorphism. Their deformation involved progressive shear, large shear strains and large shear displacements with a bulk west-over-east sense of shear related to the direction of subduction and buoyant exhumation. The Tyennan Domain shows a unique crustal architecture, including: (1) metamorphic sheets with 100 km lengths, 50 km widths and 5–10 km structural thicknesses, (2) a leading edge fold nappe with ∼200 km axial surface trace length, (3) megasheath folds with 20–25 km dimensions, and (4) asymmetric folds within regional scale shear lozenges as macro-augen. It provides an unparalleled window beneath the now, largely eroded, obducted ophiolite sheet and provides structural insight into the mechanics of continental margin subduction–obduction. Deformation has been partitioned through the composite exhumed 'slab' with domains of isoclinal macrofolds transitioning into regional scale sheath folds bounded by zones of higher strain. The higher strain zones are characterised by transposition foliation, rootless mesoscopic isoclinal folds, small-scale sheath folds, overprinting crenulation cleavages and platy mylonitic to schistose zones in quartzite. The uppermost, high-grade part of the Tyennan allochthon is clearly a composite, ∼1 km thick 'sheet' made up of a 'welded' amalgam of largely pelitic fragments that had been subducted to different depths, assembled and deformed during buoyant ascent to the current structural level. The Tyennan Domain represents the subducted part of a microcontinent during a Cambrian arc–microcontinent collision outboard of the eastern Pacific margin of Gondwana. The Tyennan Domain consists of stacked, recumbent and isoclinally folded slabs of allochthonous high-grade schist and low-grade pelite-quartzite, overlying parautochthonous low-grade dolomitic marl, quartzite and dolostone. Isoclinal, asymmetric, macrofold 'wave trains', megasheath folds and a 'leading edge' fold nappe with ∼200 km length scale dominates the structure of the Tyennan Domain. [ABSTRACT FROM AUTHOR]

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Copyright of Earthquake (1000-3274) is the property of Editorial Office of Earthquake Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on the 55th anniversary of the Plate Tectonics Theory, discussing its history, development, and current challenges. Topics include the theory's consolidation in the mid-60s with ocean floor data, alternative explanations for tectonic processes such as ridge push, and debates around continental drift and reconstruction, including the existence of ancient landmasses such as Zealandia and Madagascar's continental nature.

A case study from eastern Australia is used to demonstrate methods for subsurface high-grading and development-concept optimisation in Coal Seam Gas resource plays. We discuss two aspects of subsurface high-grading: (1) improved prediction of net coal using 2D seismic data, and (2) structure-geological analysis and mapping of the fracture network. Net-coal predictions across the study area focused on the upper Juandah Coal Measures interval of the Jurassic Walloon Coal Measures. There is a positive relationship between extracted and normalised upper Juandah Coal Measures seismic-amplitude strength and net coal in the wells. Areas with considerable amplitude dimming commonly coincide with reflector 'washout' areas mapped from seismic data and are interpreted as channel incisions into otherwise continuous coal seams. Integration of seismic and well data can improve the mapping of net coal and help optimise the placement of appraisal wells, reducing the number of unexpected or difficult-to-interpret well finds. It may also guide delineation of resource-classification domains in a more robust manner than mapping from well data alone. Fractures in coal seams of the study area are mostly bed-perpendicular joints and cleats. Three sets of fractures/cleats are identified in the coal beds: a dominant set and two more localised sets. Fracture intensity was mapped per set using well data and then combined. Fracture maps are deemed useful as an indication of permeability anisotropy, and hence the expected shape of well drainage areas, as opposed to indicating a range of permeability values. Based on the fracture interpretations, it may be possible to optimise the development concept of specific areas, i.e. varying well spacing and/or drilling wells slanted perpendicular to dominant fracture strike. Use of 2D seismic data to qualitatively indicate net-coal trends in the Walloon Coal Measures. The correlation coefficient between seismic amplitude and net coal is strong enough to guide well placement and resource delineation. Fracture intensity mapping from borehole images may indicate permeability anisotropy of the coals rather than absolute permeability values. [ABSTRACT FROM AUTHOR]

Eugène Rodolphe Faribault proved to be a very good choice as a geologist for the Geological Survey of Canada, after his appointment on July 1, 1883. His career spanned fifty years, time mostly committed to mapping the southwestern half of Nova Scotia, concentrated on the slate and quartzite of the Meguma Supergroup in which gold mining was taking place. In his words, he was, "a specialist on geological maps and structural geology of gold mines in Nova Scotia." Dozens of his meticulously prepared maps of over sixty gold districts have stood the test of time for accuracy. A popular figure in the field, Faribault made frequent trips to operating mines. He early recognized the existence, in some districts, of extensive bodies of low-grade ore. He emphasized too, the similarities between the 'saddle reef' deposits mined in the Bendigo fields of Australia and the auriferous veins of the Meguma formations. His 'pay-zone' theory held that near-surface mineable ore in Nova Scotia gold mines should continue at depth, provided the same structural conditions persisted. However, for various reasons his theory received a mixed reception. Back in Ottawa at the GSC offices, Faribault was a highly respected figure among fellow workers and supervisors alike, and across all departments. His quiet charisma and friendly nature, complemented by professional expertise, won him accolades as an ambassador well beyond the workplace. For his excellence in a young developing science, Faribault thoroughly earned the epithet, "The Grand Old Man of Nova Scotian Geology". [ABSTRACT FROM AUTHOR]

Rock fractures are a key contributor to a broad array of Earth surface processes due to their direct control on rock strength as well as rock porosity and permeability. However, to date, there has been no standardization for the quantification of rock fractures in surface process research. In this work, the case is made for standardization within fracture-focused research, and prior work is reviewed to identify various key datasets and methodologies. Then, a suite of standardized methods is presented as a starting "baseline" for fracture-based research in surface process studies. These methods have been shown in pre-existing work from structural geology, geotechnical engineering, and surface process disciplines to comprise best practices for the characterization of fractures in clasts and outcrops. This practical, accessible, and detailed guide can be readily employed across all fracture-focused weathering and geomorphology applications. The wide adoption of a baseline of data collected using the same methods will enable comparison and compilation of datasets among studies globally and will ultimately lead to a better understanding of the links and feedbacks between rock fracture and landscape evolution. [ABSTRACT FROM AUTHOR]

Tamusu area in Inner Mongolia is a candidate site for the first clay rock repository in China. Comprehensive analyses conducted on stratigraphic characteristics, mineralogy, structural geology, and three-dimensional geological modeling in the Tamusu area showed that: the thickness of clay rock is more than 200 m with burial depth ranging from 200 to 800 m, which is mainly composed of zeolite, dolomite, and illite. Fractures are not well developed and the tectonic environment is stable. Additionally, the terrain and landform are relatively flat and desolate. These findings suggest that the Tamusu area presents favorable geological conditions for the construction and operation of a high-level radioactive waste repository. [ABSTRACT FROM AUTHOR]

Plate tectonics theory, established in the 1960s, has been successful in explaining many geological phenomena, processes and events that occurred in the Phanerozoic. However, the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian period. In dealing with the relationship between plate tectonics and continental geology, continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and composition. This separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology, particularly in explaining the fundamental geological characteristics of Archean cratons. Although this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics, it led to the development of alternative tectonic models, often involving vertical movements under a regime of stagnant lid tectonics, including not only endogenous processes such as gravitational sagduction, mantle plumes and heat pipes but also exogenous processes such as bolide impacts. These vertical processes were not unique to the Archean but persisted into the Phanerozoic. They result from mantle poloidal convection at different depths, not specific to any particular period. Upgrading the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins, it is evident that plate tectonics can explain the common geological characteristics of Archean cratons, such as lithological associations, structural patterns and metamorphic evolution. By deciphering the structure and composition of convergent plate margins as well as their dynamics, the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Precambrian and modern plate tectonics in the Phanerozoic. In addition, there are the following three characteristic features in the Archean: (1) convective mantle temperatures were 200–300°C higher than in the Phanerozoic, (2) newly formed basaltic oceanic crust was as thick as 30–40 km, and (3) the asthenosphere had a composition similar to the primitive mantle rather than the depleted mantle at present. On this basis, the upgraded plate tectonics theory can successfully explain the major geological phenomena of Archean cratons. This approach provides a new perspective on and deep insights into the evolution of early Earth and the origin of continental crust. In detail, Archean tonalite-trondhjemite-granodiorite (TTG) rocks would result from partial melting of the over-thick basaltic oceanic crust at convergent plate margins. The structural patterns of gneissic domes and greenstone keels would result from the buoyancy-driven emplacement of TTG magmas and its interaction with the basaltic crust at convergent margins, and komatiites in greenstone belts would be the product of mantle plume activity in the regime of ancient plate tectonics. The widespread distribution of high-grade metamorphic rocks in a planar fashion, rather than in zones, is ascrible to separation of the gneissic domes from the greenstone belts. The shortage of calc-alkaline andesites in bimodal volcanic associations suggests the shortage of sediment accretionary wedges derived from weathering of granitic continental crust above oceanic subduction zones. The absence of Penrose-type ophiolites suggests that during the subduction initiation of microplates, only the upper volcanic rocks of the thick oceanic crust were offscrapped to form basalt accretionary wedges. The absence of blueschist and eclogite as well as classic paired metamorphic belts suggests that convergent plate margins were over-thickened through either warm subduction or hard collision of the thick oceanic crust at moderate geothermal gradients. Therefore, only by correctly recognizing and understanding the nature of Archean cartons can plate tectonics reasonably explain their fundamental geological characteristics. [ABSTRACT FROM AUTHOR]

Orthopyroxene granitoids (designated as charnockites or granitoids of the charnockite series) are characterized by varying silica and felsic mineral content, with the orthopyroxene (hypersthene) phase as the main characteristic mafic mineral component. These rocks are abyssal and represent parts of intrusions or form their own igneous complexes at the depth of the lower crust under CO2-undersaturated and dry conditions, which can be achieved within any tectonic setting. Therefore, petrogenetic models for orthopyroxene granitoids as well as for all types of granitoids from different locations are sufficiently applicable for a reconstruction of paleogeodynamic conditions in a certain region. The East Antarctic shield is characterized by Archean blocks embedded within orogens of Mesoproterozoic, Late Mesoproterozoic‒Early Neoproterosoic and Late Neoproterosoic‒Early Paleozoic age, and syn- and post-orogenic intrusions composed of orthopyroxene granitoids and related rocks are widely spread and form a prominent volume of the East Antarctic orogens. According to paleogeodynamic reconstructions of Rodinia, Pannotia and Gondwana supercontinents the East Antarctic shield represents a significant volume of supercontinents' crust. Petrogenetic models for East Antarctic orthopyroxene granitoids became fundamental for any paleogeodynamic reconstractions of supercontinents. We collected structural geology, tectonics, and geochronology data for orthopyroxene granitoid intrusions belonging to orogens of certain age and combined with the plotting of geochemical data in major and rare element tectonic discrimination diagrams, also analyzed the Sm‒Nd isotope system data. The East Antarctic orthopyroxene granitoids tightly related to orogens are characterized by magmatic sources determined as combination of mafic lower crust, upper crust and juvenile mantle materials mixing up in different proportions depending on type of orogeny. It was established that orthopyroxene granitoids related to Mesoproterozoic and Late Mesoproterozoic‒Early Neoproterosoic orogens formed at different stages of long-lived collision transforming from ocean‒continent to continent‒continent types whereas Late Neoproterosoic‒Early Paleozoic orthopyroxene granitoids arose in post-collision tectonic setting. [ABSTRACT FROM AUTHOR]

As typical carbonate geothermal reservoirs with low porosity in northern China, the Jixianian System in the Xiong'an New Area is the main target for geothermal fluid exploration. The Jixianian System comprises the Gaoyuzhuang, Yangzhuang, Wumishan, Hongshuizhuang, and Tieling formations. The characteristics, formation periods, and controlling factors of reservoir tectonic fractures have been determined based on analyses of outcrops, cores, thin sections, and image logs. The results show that unfilled fractures account for over 87% and most tectonic fractures are high‐angle shear fractures with angles concentrated at 40° to 70° and the fracture porosity increases linearly with an increased fracture aperture. Within the same tectonic setting and stress field, the lithology and layer thickness are the dominant factors governing the development of tectonic fractures, which are the most developed in dolomites and thin layers. Tectonic fractures were most likely formed in regions near faults or areas with larger stress gradients. The tectonic fractures in the carbonate geothermal reservoirs are roughly divided into four sets: NNW–SSE and NNE–SSW oriented 'X'‐conjugated shear fractures formed from the Paleozoic to the pre‐Yanshanian Movement; NE–SW‐oriented shear fractures, formed in episode B of the Yanshanian Movement, occurred at the Early Cretaceous; nearly E–W‐oriented tensional fractures formed in the late Yanshanian Movement at the Late Cretaceous to Paleogene, and NEE–SW‐oriented shear fractures formed during the Himalayan movement. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geothermal reservoirs are highly anisotropic and heterogeneous, and thus require a variety of structural geology, geomechanical, remote sensing, geophysical and hydraulic techniques to inform Discrete Fracture Network flow models. Following the Paris Agreement on reduction of carbon emissions, such reservoirs have received more attention and new techniques that support Discrete Fracture Network models were developed. A comprehensive review is therefore needed to merge innovative and traditional technical approaches into a coherent framework to enhance the extraction of geothermal energy from the deep subsurface. Traditionally, statistics extracted from structural scanlines and unmanned aerial vehicle surveys on analogues represent optimum ways to constrain the length of joints, bedding planes, and faults, thereby generating a model of the network of fractures. Combining borehole images with seismic attributes has also proven to be an excellent approach that supports the stochastic generation of Discrete Fracture Network models by detecting the orientation, density, and dominant trends of the fractures in the reservoirs. However, to move forward to flow modelling, computation of transmissivities from pumping tests, and the determination of hydraulically active fractures allow the computation of the hydraulic aperture in permeable sedimentary rocks. The latter parameter is fundamental to simulating flow in a network of discrete fractures. The mechanical aperture can also be estimated based on the characterization of geomechanical parameters (Poisson's ratio, and Young's modulus) in Hot Dry Rocks of igneous-metamorphic origin. Compared with previous review studies, this paper will be the first to describe all the geological and hydro-geophysical techniques that inform Discrete Fracture Network development in geothermal frameworks. We therefore envisage that this paper represents a useful and holistic guide for future projects on preparing DFN models. [ABSTRACT FROM AUTHOR]

The relationship between normal fault displacement (D) and length (L) varies due to numerous factors, including fault size, maturity, basin tectonic history, and host rock lithology. Understanding how fault D and L relate is useful, given related scaling laws are often used to help refine interpretations of often incomplete, subsurface datasets, which has implications for hydrocarbon and low-carbon energy applications. Here we provide a review of D/L scaling laws for normal faults, discuss factors that could influence these relationships, including both geological factors and errors in measurement, and provide a critique of previously published D/L databases. We then present our newly assembled database of 4059 normal faults from 66 sources that include explicit information on: 1) fault length and displacement, 2) host rock lithology, 3) host basin tectonic history, and 4) maturity, as well as fault D and L through time when these data are available. We find an overall scaling law of D = 0.3L0.92, which is similar to previously published scaling equations and that varies in response to the aforementioned geological factors. Our data show that small faults (<1m length) tend to be over-displaced compared to larger faults, active faults tend to be under-displaced compared to inactive faults, and faults with stiffer host rock lithologies, like igneous and carbonate rocks, tend to be under-displaced with respect to faults within softer, more compliant host rocks, like clastic sedimentary rocks. Our dynamic D/L through time data show that faults follow the hybrid fault growth model, i.e., they initially lengthen, during which time they will appear under-displaced, before accumulating displacement. To the best of our knowledge, this is the first comprehensive, integrated, critical study of D/L scaling laws for normal faults and the factors influencing their growth. These revised relationships can now be utilized for predicting fault length or displacement when only one variable is available and provide the basis for general understanding D/L scaling laws in the context of normal fault growth. This underpinning database is open-access and is available for analysis and manipulation by the broader structural geology community. [ABSTRACT FROM AUTHOR]

Zipingpu Reservoir, located in the upper reaches of the Minjiang River Basin in the middle section of Longmen Mountain in western Sichuan, is a large-scale water control project mainly for irrigation and water supply, with comprehensive benefits such as power generation, flood control, environmental protection, tourism and so on. The area of the reservoir area is 18.16 square kilometers. In May 2021, the group has carried on the detailed survey sampling in the scope, including five parts, the surface water sediment sample 6, 3 pieces of rock samples, respectively, the water of heavy metal measurement and analysis of characteristics of phytoplankton community structure, sediment measurement of heavy metals, petrophysical parameters and microscopic thin section identification, etc. Through the qualitative and quantitative analysis of the geological structure, hydrogeological conditions, it is considered that the reservoir area has the conditions for the occurrence of structural earthquakes; And the lateral percolation of the water body in the reservoir area is not strong. The environmental quality of surface water in the reservoir area is good, which is much lower than the standard limits of surface water resources class I and centralized drinking water; the content of heavy metals in surface sediments is generally between the limit of grade I and grade II of soil environment (alkalinity); the element accumulation index of the sampling site is between −4.30–0.37, indicating that there is no pollution; In which the individual samples of Cu, Cd, Cr and Pb elements 0 < Igeo < 1, and the accumulation indexes of Fe, Mn, Ni and Zn are all less than zero; the dominance index of phytoplankton in the sampling area varies from 0.00 to 0.14, with more dominant species; the range of phytoplankton density at sampling sites is 4585.9 −321019.1 cells/L, and the Shannon-Wiener diversity index is between 3.6874–4.1508, indicating that the water quality in the sampling area is relatively good, showing micro-pollution or non-pollution. It will be a hot topic to apply the methods of structural geology, environmental geology, ecological geology and so on to water environmental quality assessment. [ABSTRACT FROM AUTHOR]

The Sivrice earthquake (Mw 6.8) occurred on 24 January 2020 along the East Anatolian Fault (EAF) zone of Türkiye, and epicentral information and focal mechanism solutions were published by two national and six international seismic stations. Here, we analyzed epicentral locations and the major fault trace using aerial photogrammetric images taken two days after, and synthetic aperture radar (SAR) interferometry. Although the focal mechanism solutions were similar, the epicenters were largely displaced. Several bright lineaments with a stair-like geometry were observed in aerial images of the Euphrates River channel along the fault trace. These lineaments, also called en echelon fractures in structural geology, are like right-lateral segments of a fault plane aligning the river channel, cut and offset by those similar in trend with the EAF and with alignments of a left lateral sense, as is the EAF motion sense. We interpret that the river local channel follows a right-lateral fault structure. The traces were lost a few days later, which proves the essentiality of remote sensing technologies for obtaining precise information in large regions. The time series analysis for one year period from Sentinel-1 SAR data also illustrated the displacements in the region sourced from the earthquake. [ABSTRACT FROM AUTHOR]

Copyright of Geominas is the property of FUNDA-GEOMINAS. (Fundacion de Egresados d Amigos de la Escuela de Ingenieria Geologica y de Minas) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geominas is the property of FUNDA-GEOMINAS. (Fundacion de Egresados d Amigos de la Escuela de Ingenieria Geologica y de Minas) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geothermal reservoirs are highly anisotropic and heterogeneous, and thus require a variety of structural geology, geomechanical, remote sensing, geophysical and hydraulic techniques to inform Discrete Fracture Network flow models. Following the Paris Agreement on reduction of carbon emissions, such reservoirs have received more attention and new techniques that support Discrete Fracture Network models were developed. A comprehensive review is therefore needed to merge innovative and traditional technical approaches into a coherent framework to enhance the extraction of geothermal energy from the deep subsurface. Traditionally, statistics extracted from structural scanlines and unmanned aerial vehicle surveys on analogues represent optimum ways to constrain the length of joints, bedding planes, and faults, thereby generating a model of the network of fractures. Combining borehole images with seismic attributes has also proven to be an excellent approach that supports the stochastic generation of Discrete Fracture Network models by detecting the orientation, density, and dominant trends of the fractures in the reservoirs. However, to move forward to flow modelling, computation of transmissivities from pumping tests, and the determination of hydraulically active fractures allow the computation of the hydraulic aperture in permeable sedimentary rocks. The latter parameter is fundamental to simulating flow in a network of discrete fractures. The mechanical aperture can also be estimated based on the characterization of geomechanical parameters (Poisson’s ratio, and Young’s modulus) in Hot Dry Rocks of igneous-metamorphic origin. Compared with previous review studies, this paper will be the first to describe all the geological and hydro-geophysical techniques that inform Discrete Fracture Network development in geothermal frameworks. We therefore envisage that this paper represents a useful and holistic guide for future projects on preparing DFN models.

Abstract On February 6, 2023, two earthquakes shook the southern and central Türkiye causing significant loss of human life and devastating many cities. These are related to the active East Anatolian Fault (EAF). In this study, the digital image correlation (DIC) technique is applied to map the coseismic displacements. For that, a pair of scenes from the Sentinel-2 satellite acquired before and after the seismic events was used. The results showed that the methodological approach can be effectively used to map and monitor large-scale geological phenomena and can assist in seismic risk assessment.

ABSTRACTIn this study, we combined regional geology and geostatistical analytical processing to model the top surface of the Variscan basement in Italy. This surface, which is overlain by the pre-Alpine sedimentary cycle (Upper Carboniferous – Permian) followed by the Alpine Mesozoic and Tertiary cycles, covers a significant portion of the Italian peninsula and the Adriatic Sea.We integrated crustal seismic profiles, deep well litho-stratigraphic information and small-scale geological maps of Italy. A regional scale map of the depth of the investigated surface was thus produced using geostatistical processing.The level of reliability of our map varies depending on the distribution of subsurface data from wells and seismic profiles. However, this method is easily replicable, providing quick updates when new data become available. The map can help to identify areas with high potential for natural deep georesources and guide the exploration.

We applied an interdisciplinary approach to analyze the late Quaternary activity of the Sava Fault in the Slovenian Southern Alps. The Sava Fault is an active strike-slip fault, and part of the Periadriatic Fault System that accommodated the convergence of Adria and Europe. It is one of the longest faults in the Southern Alps. Using high-resolution digital elevation models from lidar and photogrammetric surveys, we were able to overcome the challenges of assessing fault activity in a region with intense surface processes, dense vegetation, and relatively low fault slip rates. By integrating remote sensing analysis, geomorphological mapping, structural geological investigations, and near-surface geophysics (electrical resistivity tomography and ground penetrating radar), we were able to find subtle geomorphological indicators, detect near-surface deformation, and show distributed surface deformation and a complex fault pattern. Using optically stimulated luminescence dating, we tentatively estimated a slip rate of 1.8 ± 0.4 mm/a for the last 27 ka, which exceeds previous estimates and suggests temporal variability in fault behavior. Our study highlights the importance of modern high-resolution remote sensing techniques and interdisciplinary approaches in detecting tectonic deformation in relatively low-strain rate environments with intense surface processes. We show that slip rates can vary significantly depending on the studied time window. This is a critical piece of information since slip rates are a key input parameter for seismic hazard studies.

Complex and often unobservable STEM constructs and processes are represented using a variety of representations, including iconic gestures in which the body is configured or moved to resemble a referent's spatial properties or actions. Earlier researchers have suggested links between gesturing and expertise, leading some to recommend instructional gestures. Earlier research, however, has been largely correlational; furthermore, some gestures may be made with misleading positions or movements. Using the illustrative topic of strike in structural geology, we investigated the existence and impact of inaccurate instructional gestures. In Study 1, we examined videotapes of participants who had been asked to explain strikes to another person. We observed inaccurate (non-horizontal) strike gestures not only among novices (first introduced to strike during the study itself, n = 68) but also among participants who had greater expertise in geology (n = 21). In Study 2, we randomly assigned novices (N = 167) to watch video lessons in which the instructor accompanied verbal explanations of strikes with accurate, inaccurate, or no iconic gestures and tested students' learning on a strike-mapping task. Students with low spatial-perception skills showed no impact of their gestural condition on performance. Students with high spatial-perception skills showed no advantage from accurate gestures but performed significantly worse in the inaccurate-gesture condition. Findings suggest that recommendations to use gestures during instruction should include professional development programs that reduce the occurrence of inaccurate gestures. [ABSTRACT FROM AUTHOR]

The part of China, east of the Hu Huanyong Line, is commonly referred to as eastern China. It is characterized by a high population density and a well-developed economy; it also has huge energy demands. This study assesses and promotes the large-scale development of geothermal resources in eastern China by analyzing deep geological structures, geothermal regimes, and typical geothermal systems. These analyses are based on data collected from geotectology, deep geophysics, geothermics, structural geology, and petrology. Determining the distribution patterns of intermediate-to-deep geothermal resources in the region helps develop prospects for their exploitation and utilization. Eastern China hosts superimposed layers of rocks from three major, global tectonic domainsd namely Paleo-Asian, Circum-Pacific, and Tethyan rocks. The structure of its crust and mantle exhibits a special flyover pattern, with basins and mountains as well as well-spaced uplifts and depressions alternatively on top. The lithosphere in Northeast China and North China is characterized by a thin, low density crust and mantle, whereas the lithosphere in South China has a thin, low density crust and a thick, high density mantle. The middle and upper crust contain geobodies with high conductivity and low velocity, with varying degrees of development that create favorable conditions for the formation and enrichment of geothermal resources. Moderate-to-high temperature geothermal resources are distributed in the MesozoiceCenozoic basins in eastern China, although moderate temperature geothermal resources with low abundance dominate. Porous sandstone reservoirs, karstified fractured-vuggy carbonate reservoirs, and fissured granite reservoirs are the main types of geothermal reservoirs in this region. Under the currently available technical conditions, the exploitation and utilization of geothermal resources in eastern China favor direct utilization over large-scale geothermal power generation. In Northeast China and North China, geothermal resources could be applied for large-scale geothermal heating purposes; geothermal heating could be applied during winter along parts of the Yangtze River while geothermal cooling would be more suitable for summer there; geothermal cooling could also be applied to much of South China. Geothermal resources can also be applied to high value-added industries, to aid agricultural practices, and for tourism. [ABSTRACT FROM AUTHOR]

The internal structure and architecture of evaporite sequences is often overlooked, with attention frequently concentrating on the external geometries that salt bodies form. The availability of extensive 3D seismic data affords the opportunity to interpret the internal structures within these evaporite sequences and comprehensively characterise the different structural facies over large areas. This paper concentrates on the Zechstein Supergroup evaporite deposits within the Southern North Sea of the United Kingdom's Continental Shelf. This analysis of the internal structural complexity and stratigraphic heterogeneity utilises 26,000 km2 of 3D seismic data together with over 96 wells from the Southern North Sea. Characterisation of the different structural facies present was undertaken alongside mapping their spatial distribution to understand the relationship they have with one another and the structural evolution that may have been taken. This work has (1) characterised and mapped six different internal structural facies present within the Zechstein with increasing levels of deformation; (2) shown the internal lithological heterogeneity is indicative of variations in the vertical strength profile of layered evaporite sequences; (3) discontinuous high‐amplitude reflections within the Zechstein are as a result of the geometries being too steeply dipping for the seismic data to image; and (4) the ability to possibly predict the internal heterogeneity of areas of poorly imaged salt, such as within large diapiric salt structures, from surrounding structural facies. These findings suggest that there is significant internal complexity even within areas of the basin with minor mobilisation to the external salt geometry. [ABSTRACT FROM AUTHOR]

Mineral Resource downgrades can be prevented by integrating better structural geological interpretations into project evaluations. Geological modelling for Mineral Resource estimation is presented as a systematic process of structural geological analysis at the deposit-scale using drill-sampled grade data. The initial step in this process is to use Maximum Intensity Projection (MIP) rendering to interpret axial symmetry and its orientation from the grade interval mid-points at the deposit-scale, thus reducing the modelling process's degrees of freedom to only three—estimating the prolateness of the grade or lithological distribution. This approach contrasts with the brute-force methods for assessing modelling uncertainty because the axial direction is fixed to the down-plunge orientation, thus eliminating from the outset, structurally implausible geometric configurations and unrealistic geological scenarios common in brute-force methods. Adopting this new approach of creating geological models means moving away from conventional mining industry methods that prioritise operational considerations in constructing resource estimates but fail to explain the geometric complexities of mineral deposits. We use experiments and a practical case study of a historical gold mine in Western Australia to highlight the significance of analysing the structural control of a gold deposit at the deposit-scale using raw grade data. Our research is based on anecdotal evidence suggesting that erroneous geological modelling leads to unforeseen Mineral Resource downgrades. However, we cannot confirm this hypothesis because there have been few, if any, independent public inquiries into Mineral Resource downgrades. To establish the underlying reasons for significant resource downgrades with certainty, impartial investigations (modelled on accident investigations in the aviation industry) are imperative. There is a general lack of incorporating structural geological knowledge in creating resource models, which can lead to poor outcomes such as Mineral Resource downgrades. Structural geological analysis of drill-sampled raw grade data allows the structural controls on a deposit to be better understood. We offer a simple workflow for understanding and modelling these patterns. [ABSTRACT FROM AUTHOR]

Basic, nuts and bolts structural geology is the unheralded success story central to brownfields exploration that in Australia, and globally, has grown manyfold mineral deposits beyond the start-of-mine Reserve. Since the last (2012) meeting on applied structural geology and Resources, the topic has changed dramatically. Now, structural geology is practised daily and in house by most exploration and mining companies. A diversity of settings, host rocks, control and geometry make it critical to document precisely the rocks in front of the geologist as distinct to what is in a preconceived conceptual model. It is detail that makes for new discoveries and deposit extensions. Three-dimensional computer visualisation helps with volumetric thinking, but there remains no computer alternative to the 3D cognitive geologist. Now essential structural data are integrated with other data, but the product is a hypothesis to be tested, not a silver bullet. Lineations matter and inform. The primary deliverable is images, be they hand-drawn or computer-generated showing the inter-relationships of structure, lithology, mineralisation and mine-site infrastructure/design. With their important embedded knowledge, the geologist, who took the readings, should also be entering, plotting data, synthesising, modelling and presenting to management and Directors. [ABSTRACT FROM AUTHOR]