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The study improves the understanding of the basal part of the Eocene Seeb Formation of Oman, informally known as "Unit 1", in terms of microfacies, lithostratigraphy and shale migration within the context of regional tectonics. We logged four sections bed-by-bed over a distance of 8.3 km, collected samples and analyzed thin-sections as well as XRD samples. For the first time, the microfacies and stratigraphic correlation of the lowermost part of the limestone-dominated Seeb Formation were studied in detail. In the analyzed area, Unit 1 is ~20 to 40 m thick, with the thickness increasing to the SE. In the upper part of Unit 1 is a laterally continuous shale horizon. The limestones of Unit 1 contain mostly packstones and grainstones. The dominant standard microfacies types are SMF 18-FOR and SMF 16. The former is dominated by benthic foraminifera, and the latter by peloids. Both SMFs indicate restricted lagoonal conditions. Foraminifera are common in Unit 1 and indicate a middle Eocene age. Considering the abundance of encountered foraminiferal bioclasts, it appears probable that the lagoon barrier was mainly composed of foraminiferal tests. Gutter casts, slumps and debrites indicate an active, partly unstable syndepositional slope, which was likely initially created by uplift of the Saih Hatat Dome and Jabal Nakhl Subdome. Differential regional uplift due to a more pronounced overall doming in the NW (Jabal Nakhl Subdome) than in the SE (Saih Hatat Dome) explains more accommodation space and greater thickness towards the SE. For the first time, we report visco-plastic shale migration/intrusion within the Seeb Formation, related to a shale horizon of Unit 1. This shale locally migrated as indicated by (1) local thickness variations, (2) detached limestone boulders floating in the shale, (3) limestone beds that have been cut-off by the shale and (4) dragged by the shale (5) an upward shale intrusion/injection which then spread parallelly to bedding similar to a salt tongue and (6) tilting overlying limestones. We suggest that shale migration is related to post-"mid"-Eocene E-W convergence between Arabia and India and to faulting or to the second, late Paleogene/early Neogene, faulting interval of the Frontal Range Fault. The shale horizon in the upper part of Unit 1 is a marker bed, which can be correlated across the study area. [ABSTRACT FROM AUTHOR]

Coastal boulders are often indicators of past extreme wave events. In fact, the coastal boulder distribution induced by infragravity‐dominated storm waves (energetic IG waves) may be similar to that induced by tsunamis; however, this assumption is yet to be investigated. We show that the factors responsible for generating energetic IG waves under storm scenarios are not identical to those affecting the boulders' transport distances. Our results indicate that the storm waves typically only transport boulders over short distances as compared to boulders deposited by tsunamis, even when energetic IG waves are being generated. When the dimensionless transport distance of a boulder (=transport distance of a boulder/offshore wave height) is less than 4.0 × 10 over planar topography and 3.0 × 10 over reef topography, both waves can potentially be responsible for the transport distance. In this case, whether a reasonably‐sized storm or tsunami can explain a boulder location in a study area should be investigated through detailed numerical modeling. We found a clear relationship between the dimensionless transport distance of tsunami boulders and the Iribarren number, and it is plausible to directly estimate offshore wave height or wavelength from the tsunami boulder distribution and beach slope without numerical simulation. Plain Language Summary: Coastal boulders transported by the tsunami and storm waves have been used to reconstruct the sizes and recurrence intervals of past extreme waves. Differentiating tsunamis from storm boulders is essential for revealing the characteristics of past coastal disasters. However, as the hydraulic characteristics of the tsunami and infragravity‐dominated storm waves (energetic IG waves) are similar, the distribution characteristics of these boulders are also likely to be similar. This makes identifying tsunami and storm boulders difficult. We reveal that the conditions that can easily generate energetic IG waves are not identical to those affecting the boulders' transport distances. We also show that dimensionless transport distances (=transport distance of a boulder/offshore wave height) shorter than 4.0 x 10 over planar topography and 3.0 x 10 over reef topography are characteristic of storm boulders, even storms dominated by energetic IG waves. Thus, a longer transport distance generally points to tsunami boulders even if energetic IG waves were generated during an event. Additionally, we have demonstrated that the offshore wave height and wavelength can be derived without numerical modeling if the relationship between tsunami boulders' dimensionless transport distance and the Iribarren number was used. Key Points: Even when infragravity waves dominate, coastal boulders are transported to shorter distances compared to transport induced by tsunami wavesSeabed slope angle significantly affects the transport distance of storm bouldersThe Iribarren number can be derived from coastal boulder distribution and then used to estimate offshore tsunami conditions [ABSTRACT FROM AUTHOR]

The present study aims to focus the turbulent flow characteristics over arrays of submerged boulders in a gravel bed stream. Round shaped boulders of diameter, Dc = 6 cm were staggered over a gravel bed stream (d50 = 4 cm) with varying boulder-to-boulder spacing and the flows over the arrays were studied experimentally. The flow measurements were carried out by an acoustic Doppler velocimeter and the double averaging methodology (DAM) was applied. The results of large spacing boulder array reveals near-bed velocity deficit within 1Dc upstream to 5Dc downstream of the boulder and no influence on the approaching velocity was observed after 5Dc corroborating the recovery of boundary layer. In case of medium and small spacing boulder array, the velocity deficit is significant at all locations. The shear stress distributions depict development of high and low bed shear stresses causing redistributions of the local bed shear stress. The higher magnitude of shear stress is observed at the boulder crest whereas; the secondary peak near the gravel bed crest is attributed to the skin shear stress on the individual boulder. Moreover, the present research contributes to our understanding that the boulder array on a rough bed stream leads to higher turbulent intensity at the boulder crest level. [ABSTRACT FROM AUTHOR]

The size distributions and the shapes of detrital rock clasts can shed light on the environmental history of the clast assemblages and the processes responsible for clast comminution. For example, mechanical fracture due to the stresses imposed on a basal rock surface by a body of flowing glacial ice releases initial 'parent' shapes of large blocks of rock from outcrop, which then are modified by the mechanics of abrasion and fracture during subglacial transport. The latter processes produce subsequent generations of shapes, possibly distinct in form from the parent blocks. Lacking is a complete understanding of both the processes responsible for block shape changes and the trends in shape adjustment with time and distance away from the source outcrop. Field data on edge rounding and shape changes of Shap granite blocks (dispersed by Devensian ice eastwards from outcrop) are used herein to explore the systematic changes in block form with distance from the outcrop. The degree of edge rounding for individual blocks increases in a punctuated fashion with the distance from the outcrop as blocks fracture repeatedly to introduce new fresh unrounded edges. In contrast, block shape is conservative, with parent blocks fracturing to produce self-similar 'child' shapes with distance. Measured block shapes evolve in accord with two well-known models for block fracture mechanics - 1) stochastic and 2) silver ratio models - towards one or other of these two attractor states. Progressive reduction in block size, in accord with fracture mechanics, reflects the fact that most blocks were transported at the sole of the ice mass and were subject to the compressive and tensile forces of the ice acting on the stoss surfaces of blocks lying against a bedrock or till surface. The interpretations might apply to a range of homogeneous hard rock lithologies. [ABSTRACT FROM AUTHOR]

This study compares time series of stratospheric water vapor (SWV) data at 30 and 50 hPa from 1993 to 2005, based on sets of Halogen Occultation Experiment (HALOE) profiles above the region of Boulder, CO (40 ∘ N, 255 ∘ E), and on local frost-point hygrometer (FPH) measurements. Their differing trends herein agree with most of the previously published findings. FPH trends are presumed to be accurate within their data uncertainties, and there are no known measurement biases affecting the HALOE trends. However, the seasonal sampling from HALOE is deficient at 40 ∘ N from 2001 to 2005, especially during late winter and springtime, when HALOE SWV time series at 55 ∘ N clearly show a springtime maximum. This study finds that the SWV trends from HALOE and FPH measurements nearly agree within uncertainties at 30 hPa for the more limited time span of 1993 to 2002. Yet, HALOE SWV at 50 hPa has significant and perhaps uncertain corrections for interfering aerosols from 1992 to 1994. Northern Hemisphere time series and daily SWV plots near 30 hPa from the Limb Infrared Monitor of the Stratosphere (LIMS) experiment indicate that there is transport of filaments of high SWV from polar to middle latitudes during dynamically active winter and springtime periods. Although FPH measurements sense SWV variations at all scales, the HALOE time series do not resolve smaller-scale structures because its time series data are based on an average of four or more occultations within a finite latitude–longitude sector. It is concluded that the variations and trends of HALOE SWV are reasonable at 40 ∘ N and 30 hPa from 1993 to 2002 and in accord with the spatial scales of its measurements and sampling frequencies. [ABSTRACT FROM AUTHOR]

The Sinemurian ammonoids from the boulders in the Greek quarry (Salgir River basin, southeast of Simferopol) are described. The assemblages are represented by Phylloceratidae (Phylloceras, Zetoceras, and Partschiceras), Juraphyllitidae (Juraphyllites and Paradasyceras), Schlotheimiidae (Phricodoceras), Arietitidae (Coroniceras, Metophioceras, Arnioceras, and Asteroceras), Oxynoticeratidae (Gleviceras), Echioceratidae (Plesechioceras, Orthechioceras, Echioceras, and Paltechioceras), Eoderoceratidae (Eoderoceras), Epideroceratidae (Epideroceras), and, questionably, Coeloceratidae (?Tetraspidoceras). A new species Asteroceras dommerguesi sp. nov. is described. A sequence of biostratigraphic units (biohorizons and beds with fauna) was reconstructed and correlated with known biostratigraphic units (zones, subzones and biohorizons) of the Mediterranean area. The ammonite assemblages were found to be similar to those of the Northern Tethyan margin (Pontic and Austroalpine subprovinces). [ABSTRACT FROM AUTHOR]

Objective: Although piscicides are an important tool for native fish management, our understanding of native fish population dynamics posttreatment (i.e., in putatively vacant habitat) is limited. Methods: Here, we describe long‐term trends in size and abundance of Cutthroat Trout Oncorhynchus clarkii in Lower Boulder Lake and Boulder Creek (Montana). Result: No significant differences were found before and after treatment with rotenone in mean length and population density in Boulder Creek. Posttreatment genetic samples from Boulder Lake and upper Boulder Creek consisted entirely of the Westslope Cutthroat Trout Oncorhynchus clarkii lewisi used to refound the population. Middle and lower Boulder Creek genetic samples contained 99.4% and 98.4% Westslope Cutthroat Trout, indicating that some nonnative (Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri hybrid) fish survived the treatment. Population demographics showed robust recovery posttreatment; however, genetic results revealed the limitations of a one‐time treatment—that is, an incomplete fish kill. Conclusion: We demonstrate that Cutthroat Trout populations achieve recovery after rotenone treatment in the long term, but one‐time rotenone treatments on large drainages often fail to totally eradicate populations. Therefore, managers should plan on multiple treatments and utilize environmental DNA to help achieve total removal of target species. Impact statementThe Westslope Cutthroat Trout is an iconic native species of the northern Rocky Mountains, but hybridization with introduced species, including Rainbow Trout and Yellowstone Cutthroat Trout, has greatly reduced the distribution and abundance of genetically pure populations. This case study reviews an attempt to remove a hybridized population using a single rotenone treatment before restocking with a hatchery‐reared, genetically pure population. These results can aid fisheries managers as they plan and implement fish removal projects. [ABSTRACT FROM AUTHOR]

The boulder concentrations over the stream bed and its influence on near-bed turbulent flow fields have received substantial interest of research in recent years. The present study aims to elucidate the stream-wise velocity distributions and fluid shear stress over an array of immobile boulders staggered with different boulder-to-boulder spacing namely, large, medium and small. Numerical simulation of the flows was performed using ANSYS CFX based k–ε model. The boulder concentrations decelerate the stream-wise velocity distributions below the boulder crest and the velocity deficit is apparent up to the length of wake formation at the lee sides. The results of three boulders array beds are compared with no boulder array simulation. In particular, the velocity profiles below the boulder crest reveal flow deficit up to the five boulders diameter and one boulder diameter downstream and upstream side, respectively. In the case of small spacing boulder array simulation, the flow reduction is observed in the range of 0.53 to 0.76 times the mean velocity. Moreover, the larger boulder concentrations lead to the redistribution of the local bed shear stress in the near-bed flow region and the linear stress profile of the Reynolds shear stress distributions away from the crest level. [ABSTRACT FROM AUTHOR]

Huge coastal boulders are useful to reconstruct the size of past extreme waves such as those associated with tsunamis and storms using inverse-type or forward-type boulder transport models. These models fundamentally require the precise shape of boulders. Traditionally, they have often been assumed to be rectangular or ellipsoidal with three axes measured in the field. However, if the boulder's shape is complex, this method is unable to represent the actual shape accurately. Therefore, it prevents estimation of the tsunami or storm size reasonably using models. For this reason, boulders have recently been surveyed using 3D scanning techniques such as LiDAR. However, coastal boulders now on land in tropical and subtropical areas such as Japan and Tonga are often covered by deep vegetation, which makes 3D surveys difficult. This report presents new methods to ascertain boulder shapes when they are obscured by vegetation. First, using UAV-type and mobile-type LiDAR, we scanned well-known tsunami boulders in southwestern Japan that had been covered with deep vegetation. Then, we developed a new method to extract only boulders and filter out vegetation from a point cloud. Thereby, we created 3D models of the boulders. We improved the boulder transport model further to assume the 3D boulder model accurately. In addition to coastal boulders, this filtering method is expected to be useful for unveiling any object, such as an archaeological structure, that is hidden in deep vegetation. [ABSTRACT FROM AUTHOR]

Smoothed Particle Hydrodynamics (SPH), which is a Lagrangian meshless method, is known as very useful method for large deformation problems, such as movement of wave absorbing blocks and sliding of a caisson breakwater. This study aims to simulate the movement of tsunami boulders and storm boulders, comparing with the hydraulic experiment, and evaluating the transport characteristics. The study also aims to clarify the scattering process of armour blocks on the additional rubble mound behind breakwaters against tsunami overflows. The series of simulation show the difference of movement characteristics between tsunami and storm boulders are caused by the difference of acting direction of tsunami and random waves on boulders, and hydrodynamic forces acting on the block differed depending on the block shape and initial water level conditions. [ABSTRACT FROM AUTHOR]

Steel baffle installed on footing is commonly used to resist and dissipate the impact energy from boulders carried by debris flow. However, the deformation of a baffle and the resulting energy transfer to the footing during the impact process compound the challenges of predicting the impact force and size of the footing required. In this study, full-scale experiments were conducted to simulate a boulder impacting a steel baffle installed on a square footing. The experimental data were back-analyzed using a three-dimensional (3D) finite element model, which was then used to conduct a parametric study to examine the effects of a range of impact energies and footing sizes. New design charts are developed to assess the required size of a square footing, embedded up to 2 m depth, for a steel baffle subjected to boulder impact with energy in the range of 10–100 kJ. [ABSTRACT FROM AUTHOR]

An assessment of weathered granite profile of a research area at Mukim Senai, Kulai, Johor was conducted using PLAXIS 2D method. The slope stability of weathered granite is closely related to the geometric strength of the slope, slope height, soil type (sand or clay), slope gradient and depth to determine factor of safety. The aim of this research is to model and determine the factor of safety of the weathered granite slope with homogeneous characteristics using Plaxis 2D. In addition, it also aims to analyses and correlate the effect of shapes, size and distribution of boulders to the safety factor of the slope. Finite Element Method (FEM)) had been used through the application of PLAXIS 2D software. By comparing between the 2 methods that have been analyzed, safety factors for the slopes analyzed together with groundwater data is less safe. The Safety Factor has found less than 1.5 indicates a slope prone to landslides. [ABSTRACT FROM AUTHOR]

The Moroccan coasts are occasionally inundated by storm surges and tsunamis. Local historical archives recorded some of these events, such as the storm surge of 1913 CE and the tsunami of 1755 CE. The latter remains the most destructive event the country has ever faced, with major human and economic losses recorded mainly between the two cities of Tangier and Safi. The privileged way to prevent any hazard related to these events is to study their past occurrences and impacts. However, historical evidences about these natural hazards are often very scarce to determine their return periods and evaluate their intensities. The scientific community increasingly uses sedimentary archives from coastal environments, since they offer a viable complement to historical archives. Several studies using this approach have been conducted on the Moroccan coast in recent years; however, until now, there has been no review dealing with these studies, which is the main objective of this paper. Twenty sites with traces of coastal inundation deposits have been inventoried during this work, and most of them are located along the Atlantic coast. The Mediterranean side remains poorly studied despite the presence of tsunami and storm surge risks. The review draws attention also to the absence of chronological data for most of the coastal inundation deposits recognized up to now along the Moroccan coasts, which is a major issue that prevents the determination of the return period of these events. [ABSTRACT FROM AUTHOR]

The timing of the Laurentide Ice Sheet's final retreat from North America's Laurentian Great Lakes is relevant to understanding regional meltwater routing, changing proglacial lake levels, and lake-bottom stratigraphy following the Last Glacial Maximum. Recessional moraines on Isle Royale, the largest island in Lake Superior, have been mapped but not directly dated. Here, we use the mean of 10 new 10 Be exposure ages of glacial erratics from two recessional moraines (10.1 ± 1.1 ka, one standard deviation; excluding one anomalously young sample) to constrain the timing of Isle Royale's final deglaciation. This 10 Be age is consistent with existing minimum-limiting 14 C ages of basal organic sediment from two inland lakes on Isle Royale, a sediment core in Lake Superior southwest of the island, and an estimated deglaciation age of the younger of two subaqueous moraines between Isle Royale and Michigan's Keweenaw Peninsula. Relationships between Isle Royale's landform ages and Lake Superior bottom stratigraphy allow us to delineate the retreat of the Laurentide ice margin across and through Lake Superior in the early Holocene. We suggest that Laurentide ice was in contact with the southern shorelines of Lake Superior later than previously thought. [ABSTRACT FROM AUTHOR]

In recent years, the rockfall disaster has received more and more attention, while there are few related studies on the quantitative evaluation of its risk. On the one hand, solitary stones have the characteristics of large quantity, large scale and different shapes, and the determination of the stability of solitary stone groups is a problem. On the other hand, it is difficult to assess the risk of areas affected by boulders. Therefore, taking Baiyun Mountain Primitive Forest Park in Guangzhou as the research object, the risk assessment of boulders in this area was carried out. The risk of the study area was comprehensively evaluated by considering multiple evaluation factors through qualitative and quantitative comprehensive judgment of boulder stability and precise division of the threat range of unstable boulders. The weight of each evaluation factor was calculated using the entropy weight method. Based on the highprecision digital elevation model (DEM), geographic information system (GIS) software, and rockfall analysis (RA) software, the risk level of the study area was divided into four levels: extremely high risk area, high risk area Medium and low hazard areas. The research results propose a systematic evaluation method that can be used as a reference for the risk zoning of boulder rolling hazards in other regions. [ABSTRACT FROM AUTHOR]

The timing of the Laurentide Ice Sheet's final retreat from North America's Laurentian Great Lakes is relevant to understanding regional meltwater routing, changing proglacial lake levels, and lake-bottom stratigraphy following the Last Glacial Maximum. Recessional moraines on Isle Royale, the largest island in Lake Superior, have been mapped but not previously dated. Here, we use the mean of ten new 10Be exposure-ages of glacial erratics from two recessional moraines (10.1 ± 1.1 ka, one standard deviation; excluding one anomalously young sample) to constrain the timing of Isle Royale's final deglaciation. This 10Be age is consistent with existing minimum limiting 14C ages of basal organic sediment from two inland lakes on Isle Royale, a sediment core in Lake Superior southwest of the island, and an estimated deglaciation age of the younger of two subaqueous moraines between Isle Royale and Michigan's Keweenaw Peninsula. Relationships between Isle Royale's landform ages and Lake Superior bottom stratigraphy allow us to delineate the retreat of the Laurentide ice margin across and through Lake Superior in the early Holocene. We suggest Laurentide ice was in contact with the southern shorelines of Lake Superior later than previously thought. [ABSTRACT FROM AUTHOR]

The massive deposit of medium-grained, white-colored sandstone of about 20 m thick, is located immediately above the coal seam in Quarry No. 2, resulted lesser yield due to lower powder factor (m3/kg) and over-sized boulder formations, specifically from the stemming zones at Chotia Opencast Coal Mine of M/s Prakash Industries Limited, which was operating at a depth of about 30 to 40 m with an average bench height of 5.5 m. The criticality of the problem led to the rectification of the blast design parameters through incorporation of pilot holes and pocket charges, decked charges, air-decking, evolution of static energy distributions, and fragment data analysis for establishing optimized design patterns with available machinery. Several test blasts along with on-site testing of explosive quality, rebound hardness tests of overlying strata, and rearrangements of firing patterns through surface delay connections were considered for adopting the best-suitable blast pattern for the mine. Generalized and perceptible inferences were made to apply the results in other mines with similar kinds of problems. [ABSTRACT FROM AUTHOR]

2 Arcos, Drumhiller and Phythian, I The Academic-Practitioner Divide in Intelligence Studies, " i Navigating the Academic-Practitioner Divide in Intelligence Studies", 1-40. 3 Ibid., 8. 4 Ibid., 17. 5 Ibid., "Intelligence, Science, and the Ignorance Hypothesis", 88. 6 Ibid., "The Academic-Practitioner Divide in Intelligence: A Latin-American Perspective", 219-236. The academic-practitioner divide in intelligence studies: edited by Rubén Arcos, Nicole K. Drumhiller, Mark Phythian, Lanham, Boulder, New York, London, Rowman & Littlefield, 2022, 318 pp., Hardback $120.(£92.00), eBook $35.00 (£29), ISBN 9781538144466 Until the 20th century the development of intelligence as a branch of statecraft was irregular. [Extracted from the article]

In this study, the weathering forms on the andesite of volcanic Mount Ağın (1807 m) located within the borders of Afyonkarahisar province in the Central Western Anatolia part of the Aegean Region were investigated. The climatic characteristics of the study area, chemical and mineralogical-petrographic properties of the andesites, porosity, diaclase systems, and biogenic erosion cause formation of characteristic shape generations on the andesites. In the field, andesites have been weathered by mechanical effects based on salt crystallization, freeze-thaw, shrinkage-expansion, and by the chemical effects of waterbased on hydrolysis-hydration-oxidation. The weathering product formed as a result of differential weathering has been subsequently moved by erosion, and the unweathered parts came to the surface to form distinctive forms in the topography. Weathering forms seen on the andesites have been investigated in detail for the first time in Turkey. The aim of this study is to reveal the close relationship between erosional forms of "andesite topography" and the factors playing a significant role in the formation of these weathering features. According to field observations and laboratory analyses, the original weathering forms on the mass have been explored and classified, and consequently revealed their formation mechanism and morphometric properties. [ABSTRACT FROM AUTHOR]

But in between, the chapter turns back to terrorism and then the Federal Bureau of Investigation (FBI), which, of course, is unconnected with the Department of Homeland Security (DHS) or, at least in this discussion, FEMA.[4] Then the next chapter covers the component agencies within DHS, with some emphasis on the risks and missions but no particular intelligence focus. Neither health surveillance nor the kind of international-level intelligence about a sovereign state that the China-coronavirus issue entails involves DHS or the homeland security enterprise under current law and policy. There is a surprise twist at the end of Jeffrey Douglas Dailey and James Robert Phelps' I Intelligence for Homeland Security: An Introduction i : The authors analyze the Federal Emergency Management Agency (FEMA) in terms of its acquisition and uses of intelligence - and find FEMA's model to be working, perhaps even an example of how homeland security (note the lower case) might understand and employ intelligence better. [Extracted from the article]

One of the most undesirable consequences induced by blasting in open-pit mines and civil activities is flyrock. Furthermore, the production of oversize boulders creates many problems for the continuation of the work and usually imposes additional costs on the project. In this way, the breakage of oversize boulders is associated with throwing small fragments particles at high speed, which can lead to serious risks to human resources and infrastructures. Hence, the accurate prediction of flyrock induced by boulder blasting is crucial to avoid possible consequences and its' environmental side effects. This study attempts to develop an optimized artificial neural network (ANN) by particle swarm optimization (PSO) and jellyfish search algorithm (JSA) to construct the hybrid models for anticipating flyrock distance resulting in boulder blasting in a quarry mine. The PSO and JSA algorithms were used to determine the optimum values of neurons' weight and biases connected to neurons. In this regard, a database involving 65 monitored boulders blasting for recording flyrock distance was collected that comprises six influential parameters on flyrock distance, i.e., hole depth, burden, hole angle, charge weight, stemming, and powder factor and one target parameter, i.e., flyrock distance. The ten various models of ANN, PSO–ANN, and JSA–ANN were established for estimating flyrock distance, and their results were investigated by applying three evaluation indices of coefficient of determination (R2), root mean square error (RMSE) and value accounted for (VAF). The results of the calculation of evaluation indicators revealed that R2, values of (0.957, 0.972 and 0.995) and (0.945, 0.954 and 0.989) were determined to train and test of proposed predictive models, respectively. The yielded results denoted that although ANN model is capable of anticipating flyrock distance, the hybrid PSO–ANN and JSA–ANN models can anticipate flyrock distance with more accuracy. Furthermore, the performance and accuracy level of the JSA–ANN predictive model can estimate better compared to ANN and PSO–ANN models. Therefore, the JSA–ANN model is identified as the superior predictive model in estimating flyrock distance induced from boulder blasting. In the final, a sensitivity analysis was conducted to determine the most influential parameters in flyrock distance, and the results showed that charge weight, powder factor, and hole angle have a high impact on flyrock changes. [ABSTRACT FROM AUTHOR]