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The post-grouting technique has gradually become an effective approach to improve the bearing capacity of piles in calcareous sand due to its simple process, low cost and reliable reinforcement effect. In this paper, model tests were performed on horizontally loaded single piles under static pressure pile driving in a calcareous sand foundation. The responses of ungrouted piles and post-grouted piles subjected to lateral loads in calcareous sand were studied, the test results were compared with those of ungrouted piles and post-grouted piles in siliceous sand, and the influence of postside grouting on the horizontal bearing behavior of piles in calcareous sand was explored. The results show that due to the particularity of the calcareous sand, its horizontal restraint ability of ungrouted piles is weaker than that in siliceous sand. Post-grouting at the pile side has a significant effect on improving the horizontal bearing capacity and strengthening the deformation control ability of the pile in calcareous sand, while showing approximately the same characteristics as that of the post-grouted pile in siliceous sand under the same conditions. The ratio of the lateral resistance coefficient of ungrouted and post-grouted piles gradually tends to be consistent with the increase in the lateral displacement of the pile head, and the bending moment and lateral displacement of the pile shaft are mainly concentrated in the upper part of the pile shaft. The lateral bearing capacity of the pile is greatly affected by the upper level of soil, and grouting at the pile side can effectively increase the ability of the pile foundation to resist horizontal loads and control deformation by improving the physicomechanical properties of the upper soil layer. In addition, the distribution and microstructure of cement-stabilized soil are analyzed based on the excavation of a post-grouting single pile. It is found that the cement grout injected at the pile side moves upward, penetrates downward and diffuses horizontally along the pile shaft to form a stable structure of cement-stabilized soil with calcareous sand particles; therefore, the pile–soil system interaction enters a new structural equilibrium state, thereby improving the horizontal bearing capacity of the pile foundation in calcareous sand.

This study was to determine the physical properties of the soil and the effect of adding coconut ash to the permeability coefficient using the fall method. Soil sampling was carried out in Bolu Village, Rantepao District, North Toraja Regency and the added material used coconut fiber from community waste located on Biring Romang Street, Kapasa Village, Makassar City with the proportion of added material being 0%, 5%, 10%, and 15%. The structure in this research is to use research on the physical properties of the soil and then compile the composition of the alloy to the soil permeability test so that it can produce a coefficient of soil permeability. The results of this study indicate that the soil meets the characteristics as clay soil. The effect of adding fiber ash to the soil is a decrease in the permeability value where the higher the proportion of coconut fibers, the smaller the permeability until the addition of 15%.

An almost continuous layer of Upper Cretaceous deposits up to 1000 m thick was probably deposited across much of SW England. Phases of uplift in the late Cretaceous and early Cenozoic, each of which was followed by extensive erosion and dissolution, resulted in the removal of all except a few outliers of Chalk Group that crop out in east Devon and south Somerset. Those on the Devon coast between Sidmouth and Lyme Regis are some of the best exposed Cenomanian to early Coniacian successions in NW Europe and include the most westerly chalks preserved onshore in England. They form an integral part of the Dorset and East Devon World Heritage Site. In contrast to the Chalk of much of southern England, the older formations in Devon, the Beer Head Limestone, Holywell Nodular Chalk and New Pit Chalk, show marked lateral lithological variations that result from a combination of penecontemporaneous movements on local faults and relatively shallow-water environments close to the western edge of the Chalk depositional basin. The younger parts of the succession, the Lewes Nodular Chalk and Seaford Chalk Formations, comprise chalks that do not appear to have been greatly affected by penecontemporaneous fault movements. These formations include lithological marker beds that have been correlated with marker beds in the Sussex type area. The principal sedimentary breaks in the Devon succession cannot be correlated with confidence with eustatic changes in sea level.

Groundwater-withdrawal-induced land subsidence has been a big concern in Montgomery County, Texas, U.S. since the 2000s. As of 2020, approximately half of the entire county is experiencing subsidence over 5 mm/year. This study aims to investigate ongoing land subsidence in Montgomery County using groundwater-level, extensometer, and GPS datasets. According to this study, land subsidence in Montgomery County since the mid-2000s is primarily contributed by sediment compaction in the Evangeline and Jasper aquifers; the compaction of Jasper aquifer contributes approximately one-third of the land subsidence since the mid-2000s; the pre-consolidation heads of the Chicot, Evangeline, and Jasper aquifers in Montgomery County are close to each other, approximately 15–25 m below mean sea level; the virgin-compaction/head-decline ratio is approximately 1:250 in the Evangeline aquifer and 1:800 in the Jasper aquifer in central and southern Montgomery County. As of 2020, the Jasper groundwater-level altitude is approximately 20–40 m below the pre-consolidation head in the central and southern Montgomery County; the Evangeline groundwater-level altitude is about 40–60 m below the pre-consolidation head. Land subsidence will continue to occur as long as the groundwater-level altitude in either the Evangeline or the Jasper aquifer remains below the pre-consolidation head.

Recent research does not fully identify the causes of surface volume loss that occur at the tunnel level in sand, as related to the excavation of a pressurized-face tunnel boring machine (PTBM). This paper focuses on the face stability of PTBM tunneling, and the response of sandy soil to the inadequate face pressure is evaluated. Data presented are from tests of a model using reduced-scale PTBM tunneling operations in dry sand. Ground displacement and the evolution of ground stress were analyzed. The relationship between the load factor at the face and the volume loss at surface was examined. The effects of soil density and tunnel depth were considered. An empirical formulation was provided allowing determination of the expected volume loss as a function of load factor (LF), cover-to-diameter ratio (C/D) and soil density (Id). Thus providing a valuable basis for establishing relationship between volume loss associated with tunnel face advancement and face pressures in sandy soil. The results show that instability of the face is accompanied by the triggering of secondary deformation mechanisms at the surface. The volume loss at surface is complicated by the combined effects of soil arching and the dilative/contractive behavior of the soil. The variation of volume loss is sudden prior to face collapse, especially at dense sand, which is different from the progressive variation of volume loss in clays. The size of destressed zone ahead of cutter head is less dependent on C/D in loose soil than in dense soils.

The article discusses the results of interdisciplinary studies of a Romanesque stone head of high-quality artistry. It was discovered in 2017 during excavations at Nowy Targ (New Market) Square in the city of Wrocław (Lower Silesia, Poland). The sculpture originally came from one of the Romanesque sacred buildings of Wrocław, none of which have survived to this day. Although it had been made in the mid-12th century, it was found in the remains of a wooden residential building burnt down in the 14th century. The results of petrographic analyses indicate that the stone head was made of fine-grained sandstone classified as lithic wacke. The raw material was most likely a Devonian-Carboniferous sandstone from the Opava Mountains. However, similar sandstones also occurred in several medieval mines located in Upper Silesia. According to a popular belief, medieval aesthetics required such sculptures to be polychromed. The non-destructive analyses conducted with the microscopic XRF , XRD , and FTIR methods demonstrated that a clean stone surface was also acceptable.

On 7 February 2021, a catastrophic flood destroyed two hydropower plants, killing at least 150 people in the Himalayan Uttarakhand state of India. This flood was reportedly initiated by a high-position landslide. This work explored the capability of using Sentinel-2 images to diagnose the landslide trigger of this event. There were 264 Sentinel-2 images taken before the landslide, 111 of which are clear. In a pre-landslide Sentinel-2 image, tensile cracks are clearly visible on the landslide head. In the post-landslide image acquired on 10 February 2021, a fresh landslide scarp stripped of snow is visible, indicating that a high-position landslide occurred that may have led to the disaster in the downstream areas. The landslide was initiated at an elevation of ~ 5600 m, slid to the valley floor (~ 3800 m elevation) and scooped up an unconsolidated mixture of moraine, ice and water that wreaked havoc on local infrastructure. To derive the slope deformation that occurred before the landslide, we selected 15 Sentinel-2 images to compose 10 image pairs. To filter out background noise, we developed a new method to derive reliable slope deformation results. We found that the slope was consistently moving since 2016, after which it moved at least 25 m. We speculated that the slope instability was caused by the seasonal freeze–thaw process. With the impacts of climate warming, more similar hazard chains are expected in the Himalayan region. The regular monitoring of slope stabilities in the Himalayan Mountains and beyond is urgently needed for regional sustainability.

The Greater Caucasus mountain belt is characterized by deep valleys, steep slopes and frequent seismic activity, the combination of which results in major landslide hazard. Along the eastern side of the Enguri water reservoir lies the active Khoko landside, whose head scarp zone affects the important Jvari-Khaishi-Mestia road, one of the few connections with the interior of the Greater Caucasus. Here, we present a database of measurement time series taken over a period of 4 years (2016–2019) that enable to compare slope deformation with meteorological factors and man-induced perturbations owing to variations in the water level of the reservoir. The monitoring system we used is composed of two digital extensometers, placed within two artificial trenches excavated across the landslide head scarp. The stations are equipped also with internal and near ground surface thermometers. The data set is integrated by daily measurements of rainfall and lake level. The monitoring system was set up in the framework of a NATO-funded project, aimed at assessing different types of geohazards affecting the Enguri artificial reservoir and the related hydroelectrical plant. Our results indicate that the Khoko landslide displacements appear to be controlled by variations in hydraulic load, in turn induced by lake level oscillations, with a delay of months between lake infilling and extension rate increase. Rainfall and temperature variations do not seem to affect slope deformations. The full databases are freely available online at DOI: https://doi.org/10.20366/unimib/unidata/SI384-1.1 (Tibaldi et al., 2020).

Five women are scattered across the braes, close to the foot hills of the plateau above. The expanse is large enough that you cannot capture them all in your gaze and you need to move your head to ...

Scar Crags and Dale Head North in the English Lake District host mineralised veins enriched in ‘Energy Critical Elements’ (ECEs) specifically, bismuth, cobalt and copper. A limited number of studies in the 1970s investigated the mineralogy and inferred the genesis of these veins as being related to the intrusion of the Lake District batholith.This study investigates the geology, mineralogy, composition and paragenesis of these two mineralised areas. The results highlight the ubiquitous presence of Co–Fe–Ni-sulfarsenides in both deposits and the presence of some mineral species, hitherto unreported. Scar Crags samples contained high concentrations of cobalt, commonly present within arsenopyrite, whereas cobalt is of minor importance at Dale Head North, where copper and arsenic are the primary metals. A sequence of events, with As–Co–Ni-bearing fluids infilling the veins after an initial stage of quartz and chlorite precipitation is the most striking resemblance between the two mineralised systems, potentially indicating a common process for Co-rich vein-type deposits in the area. If so, understanding such processes could prove vital in aiding exploration in other terranes.

The new Istanbul Airport is being constructed over an old coal field area, 35 km away from the city center. The construction of a rail link between the city and the airport entails the excavation of tunnels in the areas of complex geology, creating several problems for tunnel construction. This paper summarizes the effect of different grades of weathering of an interbedded sandstone-mudstone-siltstone sequence and transition zones on the performance of an earth pressure balance tunnel boring machine (EPB-TBM) during this work. The variation of EPB pressure, TBM thrust, torque, penetration, and specific energy values were analyzed in different lithologies and weathering zones and with respect to the attitude of transition zones between different materials. Normalized thrust and torque values considered in respect of penetration rate and EPB pressure showed that the attitude of transition zone on TBM performance is strictly dependent on the position of each geologic formation in the respect to the other, inclined or horizontal. To be specific, in an inclined transition zone, the thrust and torque values were almost double compared to the values obtained in a horizontal transition zone in the same lithology. This was probably due to increased over-break in inclined transition zones, which created loose material that accumulated in front of the cutter head. However, further case studies would be required definitely to confirm this. Mean normalized thrust and torque values were almost half in moderately/highly weathered sandstone compared to fresh/slightly weathered sandstone. The highest mean penetration of 28 mm/rev and mean lowest specific energy of 2.4 kWh/m3 were obtained in transition zone between claystone with silty sand and highly weathered interbedded sandstone-mudstone-siltstone. Due to impact effects, increased disc consumption was experienced where passage was made from low strength due to high strength formations, with up to one disc per 115 m3 of excavated material in the transition zones included in the study. The relatively high production rates were achieved, which attributed to a combination of logging daily the face conditions accompanied by appropriate adjustments of soil conditioning agents (FIR-foam injection ratio and FER foam expansion ratio values) and anti-clogging agents to control the sticking behavior of the spoil. The impact of different ground conditions on EPB-TBM performance in different projects is also discussed in relation to the results obtained in this study. It is believed that this research will help to manage better mechanized tunneling activities in similar conditions.

The distribution and origins of Ni and V were assigned in the surficial sediments from 160 stations in Shadegan international wetlands with 537,700 ha. The findings showed that the mean total content of Ni and V in the surface sediments were 45.08 ± 12.09 and 25.25 ± 20.8 μg g−1 dw, respectively. According to the analysis chemical speciation, the Ni and V residual fraction in the surface sediments were calculated for > 80% of the total level of metals, indicating that the metals may be an indicator for the input of natural resources. The analysis of the interpolation maps according to their chemical fractionation manifested that the Ni and V pollution hotspots have been happened in the northern, southern, and western points. Interpolation maps also highlighted that Ni and V are often controlled by natural factors like parent material; however, anthropogenic inputs have also caused the accumulation of these metals in the sediment.

Boulders are spheroidal and weathered rock fragments that exist in softly weathered granite strata. Boulders can cause severe damage to the cutter heads of shield machines and can even lead to the failure of shield tunneling during the excavation of metro tunnels in granite strata. However, there is no effective method to safely and rapidly cope with this problem on a large scale. This study proposes a method to detect and to pretreat boulders during shield tunneling within granite strata. The detection method is a combination of microtremor surveying and supplementary drilling exploration to ensure both rapid, large-scale detection and high detection accuracy. Based on the microtremor survey results, principles of interpretation are developed to predict the presence of boulders and evaluate the safety status of shield tunneling. Furthermore, the predicted boulders are precisely confirmed by supplementary drilling exploration. After the boulder locations are detected, a combined surface drilling and preblasting technique are adopted to pretreat the boulders. This method was successfully applied in the shield tunneling of Fuzhou Metro Line 5 in China. The application shows that this method is effective for the prediction and pretreatment of boulders during shield tunneling. The prediction of boulders has high accuracy. The preblasting of boulders improves the tunneling efficiency, which significantly reduces the total thrust and torque on the cutter head, and markedly increases the tunneling speed.

We describe aggregative microconchid (Lophophorata) tubes from the uppermost Permian (upper Changhsingian) and Lower Triassic (Olenekian) lacustrine and fluvial strata of the Tunguska and Kuznetsk basins and the southern Cis-Urals, Russia. These attach to clam shrimp carapaces, bivalve shells, terrestrial plant fragments and a horseshoe crab head shield, and also form their own monospecific agglomerations. Planispiral tubes of a wide size range (0.1–2.5 mm) create dense settlements on these firm substrates, which likely comprise multiple generations of the same species. These finds confirm that this extinct lophophorate group was inhabiting non-marine continental basins during latest Permian and earliest Triassic time, when they were major suspension feeders in such limnic ecosystems. Microconchids dispersed extensively and rapidly in the aftermath of the Permian–Triassic mass extinction into both marine and continental basins at low and moderately high latitudes, which were notably different in salinity, temperature, depth and redox conditions. This confirms that small lightly calcified microconchids were a genuine disaster eurytopic group, whose expansion may have been promoted by low predator pressure and low competition for substrate.

Gullies in semi-arid region are important in landscape modification, degradation and increased overland flow affecting geomorphic thresholds of an area. Gullies generate about 95% of global sediment load, important in landscape modification, degradation and increased overland flow in semi-arid regions, but little is known on geomorphic factors that increase ecological fragility increasing gully initiation. To address the problem, landscape regions of accelerated geomorphic processes must be determined. The study aimed to establish topographical thresholds and geomorphic factors which increase landscape fragility in gully head positions in different geographical regions. Gully heads were analyzed by detailed field surveys from 10 m up and down-slope position. Drainage area contributing to gully was demarcated from the point overland flow was assumed to reach the gully head based on water visible flow-lines while gully head slopes were determined by use of clinometers. Gully threshold concept was applied to identify the critical slope (S) and drainage area (A), using appropriate S - A relation (S = aAb) and verified using ANOVA. The empirical S - A threshold relation S = 0.383A-0.397, R2 = 0.0321 (upper-segment), S = 0.174A-0.032, R2 = 0.498 (mid-segment), S = 0.23A-0.020, R2 = 0.088 (lower segment), represented approximate critical slope-drainage area for gully initiation and regions of dominant geomorphic processes, above which gully initiation was likely to occur. Negative b values represent an areas more dominated by overland flow over sub-surface processes. Coefficient of correlation multiple R = 0.7055 (70.55%) Mid-segment indicated strong relation slope-drainage area for gully initiation. ANOVA analysis p = 0.01, 0.004 and 0.4498 for upper, mid and lower segment respectively revealed stronger relation between independent and dependent variables. p > 0.05 indicated regions influenced by more factors than slope and drainage area. Thus, slope-drainage threshold relation line can be applied in the semi-arid environments to locate vulnerable sites of dominant geomorphic processes which should be checked for gully conservation.

The status of the pebble artifacts found on the seashores and banks of the lakes in the sacral places is being discussed intensively in modern archaeology during recent years. Many of suchlike engraved stone sculptures in a shape or with the images of a bear, a bird, an elk/deer, etc. were found in the Urals and Siberia. All finds are connected with the cult places of worship, namely, painted cliffs or petroglyphs. The shamans’ burials also were found nearby. This article presents a new find made by the author in summer, 2020 on the Sea of Azov shore, on Pavlo-Ochakovskaya spit—the sandy beach in the Gulf of Taganrog, Rostov-on-Don Region. The shape of this pebble is of the canonized form of an elk/deer head and it looks like the artifacts from: Kazachka-I, the basin of the river Yenisei; Zamostie-2; Podty 1 (Komi Republic) and Mikhailovka-Klyuch (Osinoozersk culture), western Amur region archaeological sites. The previous findings of the similar shape were found not only on the open spaces but also in the archaeological layers. Archaeology still does not have a clear answer to the question of the usage of this kind of artifact. A new find from the Sea of Azov shore has an image of a running deer, which is partially painted and partially engraved. It has an incision marking the muzzle of a deer and very thin lines crossing the deer’s body. With the help of comparative study and interdisciplinary approach in this paper, we found out that similar stone sculptures in the shape of an elk/deer head were the markers of the migrated tribes since Paleolithic and can be attributed as the symbols of the Great Goddess—a divinity of mountains, stones and fertility cult widely spread in Eurasia since the Upper Paleolithic.

The US and many parts around the world have experienced prolonged periods of heavy rainfall, severe floods, and droughts over the past 50 years. This study investigates the impacts of extreme hydrological events such as heavy rainfall and flood on the settlement behavior of continuous footing installed in unsaturated soil using a coupled Geotechnical-Hydrological finite element software, PLAXIS 2D. Initially, the effect of different degrees of saturation on the settlement behavior of the continuous footing of widths 1.5 m, 3.0 m, and 4.5 m was analyzed by applying a mechanical load. Then the settlement behavior of the footing was analyzed by applying heavy rainfall of intensity 102 mm/day for six days. Finally, the settlement behavior of the footing was analyzed by applying a flood head of 2.5 meters for seven days. The results indicated that the wetting front movement during heavy rainfall and flooding led to the weakening of soil strength and stiffness and induced additional settlements. The additional settlement induced by the flood was significantly higher than the heavy rainfall. The differential settlement was higher when the rainfall was applied on one side of the footing. The rebound of the elastic settlement was uniquely noticed when the flood head receded with time. The results indicated that not all the settlements were induced by the soil saturation but also due to the hydrostatic loading due to the flood head. The settlements induced by the flooding exceeded the allowable settlement of 25 mm, resulting in failure. These additional settlements caused by heavy rainfall and flood will lead to poor serviceability of the structures and cause the failure of the footing.

The Mayoon landslide in the Hunza District is a slowly developed, non-catastrophic landslide that has gained its importance in the last few years after its rapid activation and fast slip rate. The area is characterized by high earthquake hazards (zone 3 with a peak ground acceleration value of 2.4–3.2 m/s2) by the Building Code of Pakistan due to frequent earth quakes. The past high earthquake activity in the area has displaced the foliated rocks towards the south and is responsible for opening the bedrock joints. The head and body of the landslide are covered by unconsolidated material and have fractures of varying lengths and widths. The non-invasive geophysical techniques, including Ground Penetrating Radar (GPR) and Electrical Resistivity Soundings (ERS), are deployed to evaluate the Mayoon landslide subsurface. The subsurface is interpreted into a two-layer model. Bright reflectors and highly variable resistivity characterize the top layer (Layer-1). This layer is associated with a loose, highly heterogeneous, fragmented material deposited under glacial settings over the existing bedrock. Hyperbolic reflections and intermediate resistivity characterize the bottom layer (Layer-2). This layer is associated with foliated metamorphic bedrock. The hyperbolic reflections show faults/fractures within the bedrock. The extension of these fractures/faults with depth is uncertain due to decay in the GPR signal with depth. The intermediate resistivity shows the bedrock is weathered and foliated. Reflections within Layer-1 have disrupted directly above the fractures/faults suggesting a possible movement. A bright reflection between the two layers highlights the presence of the debonded surface. Loose material within Layer-1 coupled with debonding possesses a significant hazard to generate a landslide under unfavourable conditions, such as an intense rainstorm or earthquake activity., Klizište Mayoon u distriktu Hunza pripada skupini sporo razvijajućih, nekatastrofičnih klizišta. Važnost mu je porasla u nekoliko zadnjih godina nakon što se klizanje znatno ubrzalo. Cijelo područje obilježeno je visokim potresnim rizikom (zona 3, s najvećim ubrzanjem tla 2,4 – 3,2 m/s2), a u skladu s pakistanskim propisima o gradnji. Snažni potresi u prošlosti pomaknuli su blokove metamorfnih stijena prema jugu i uzrokovali otvaranje brojnih pukotina u stijenama podine. Čelo i tijelo klizišta prekriveno je nekonsolidiranim materijalom te ima pukotine različitih širina i dužina. Prostor klizišta istražen je neinvazivnim geofizičkim tehnikama poput georadara i mjerenja električne otpornosti. Podzemlje je prikazano dvoslojnim modelom. Prvi sloj (1) predstavljen je snažnim reflektorom i vrlo promjenjivom otpornošću. Sastavljen je od rastresitih, vrlo heterogenih, fragmentiranih materijala taloženih tijekom glacijala preko stijenske podine. Ispod je drugi sloj (2) obilježen hiperboličkim refleksima te umjerenom otpornošću i pruža se unutar folijacijskih, metamorfnih stijena. Oblik refleksa upozorava na rasjede i pukotine podine, no oni se teško prate s povećanjem dubine. Otpornost također upućuje na trošenje i folijaciju. Refleksi u sloju 1 prekidaju se iznad rasjeda i pukotina upozoravajući na moguće gibanje. Snažni refleksi između dvaju slojeva naglašavaju postojanje granice između njih. Rastresiti materijal u sloju 1, zajedno s postojanjem takve granice, predstavlja znatan rizik nastanka klizišta, posebice u rizičnim uvjetima poput olujnoga pljuska ili potresa.

A good understanding of giant landslide-prone areas could greatly enhance the understanding of the formation and failure mechanisms of giant landslides. In this study, a classic giant landslide-prone area named the Diexi area located along the upstream stretch of the Minjiang River on the eastern Tibetan Plateau is adopted to analyze the failure mechanism and evolution process by detailed field investigations, Unmanned Aerial Vehicle (UAV) images and a digital surface model (DSM). The results show that among the 37 giant landslides located in the Diexi area, 18 landslides are transverse landslides (wedge failure), and the others are consequent landslides (buckling failure). All landslides blocked rivers, and some barrier lakes still remain. The Diexi area features special geological structural conditions related to the hinge section of the Jiaochang arc tectonic belt, the intersection of two active fault zones (the Songpinggou and Minjiang fault zones) and high levels of geostress. The numerous radial fissures induced by the Jiaochang arcuate belt provided lateral sliding boundaries for buckling deformation (consequent landslides) and head scarps for wedge failure (transverse landslides). The rapid incision (1.88 mm/yr) since the middle Pleistocene formed a deep gorge with steep slopes and strong lateral unloading. Frequent earthquakes and rainfall further reduced the rock mass integrity, and strong earthquakes or other factors triggered the landslides.

The morphological evolution of the sand barrier in the Anhaiao coastal zone of Pingtan from 1996 to 2018 was studied. Tidal correction was used to refine the location of the coastline. A standard deviation ellipse method was applied to further analyze the movement of the barrier head with the axis and rotation angle. A natural neighbor interpolation (NNI) method was carried out to calculate the terrain of the intertidal area, and the erosion and deposition characteristics were illustrated based on the terrain. The results showed that the northern part of the sand barrier facing the lagoon area was deposited over the whole studied period, while erosion has always occurred in the southern part of the sand barrier facing the open sea. The erosion and deposition were slightly different on both sides of the barrier head due to hydrodynamic turbulence. The middle sand barrier moved 102.60 m away from its original location in 1996, and the end of the barrier moved 65.45 m. The head of the sand barrier continued moving 379 m to the northwest. Consequently, the preliminary morphological evolution of the sand barrier corresponding to the distance and direction of movement was detected.

A late 13th-century survey of Berwick-upon-Tweed includes an entry entitled ‘la Roundele’. It has not previously been interpreted satisfactorily but this paper shows it to have been a large circular site, in a secondary use by the time of the survey, at the head of the town’s early beachside marketplace. It is argued that the site’s shape, size and ability to survive in the changing townscape means that it originated in a substantial earlier structure – such as a broch or similar complex Atlantic roundhouse. The proposition accords with what is known of the early history of the Tweed estuary and southern brochs in general. Archaeological evidence for the structure may survive beneath later buildings. Canmore ID 25990

A região do Distrito Federal de Brasília possui uma camada superficial formada por solo geralmente argiloso, poroso e colapsível cuja espessura varia de poucos centímetros a vários metros. Devido à presença dessa camada de solo poroso colapsível no Distrito Federal é comum o uso de fundações profundas. As inclusões têm sido estudadas e utilizadas com a finalidade de controlar os recalques e diminuir os custos nas fundações de edifícios de pouca altura sobre solo mole, porém, no caso do Distrito Federal elas objetivam superar os problemas oriundos do colapso estrutural da camada de solo poroso. Os autores têm estudado o uso de fundações com inclusões rígidas como alternativa para o controle de recalque nos solos colapsíveis do Distrito Federal, demonstrando seu bom desempenho. Neste trabalho são avaliadas, usando-se modelagem numérica axissimétrica, as tensões sob radier induzidas pelos topos das inclusões rígidas implantadas no solo colapsível de fundação. Para isso foram realizados vários modelos onde foram variados os espaçamentos entre inclusões, a altura de camada de distribuição e a estratigrafia. Os resultados mostram a influência das características geométricas da fundação e do tipo de estratigrafia no desenvolvimento de tensões sob o radier. As análises mostram ainda ser possível definir o arranjo geométrico em que as tensões induzidas sob o radier pelas cabeças das inclusões são mínimas, o que constitui uma vantagem deste tipo de solução de projeto de fundação uma vez que diminui a solicitação estrutural do próprio radier reduzindo o seu custo.

Significance This article tackles the longstanding question of why some continental rifting was associated with major pulses of excess volcanism that formed “volcanic rifted margins,” yet other rifting, even nearby, was not. After reviewing the South Atlantic rifting exemplar, we present results from an improved type of three-dimensional calculation of mantle flow that avoids many of the artificial boundary condition-related pitfalls in prior numerical studies that did not predict asymmetric rift-related volcanism. Our experiments match the observed development of asymmetric volcanism during South Atlantic rifting, with important implications for plume-influenced rifting of continents. In particular, the scenario does not require a conventionally assumed “starting plume head” to provide the hotter-than-average mantle that induces excess rift magmatism., Volcanic rifted margins are typically associated with a thick magmatic layer of seaward dipping reflectors and anomalous regional uplift. This is conventionally interpreted as due to melting of an arriving mantle plume head at the onset of rifting. However, seaward dipping reflectors and uplift are sometimes asymmetrically distributed with respect to the subsequent plume track. Here we investigate if these asymmetries are induced by preexisting lateral variations in the thickness of continental lithosphere and/or lithospheric stretching rates, variations that promote lateral sublithospheric flow of plume material below only one arm of the extending rift. Using three-dimensional numerical experiments, we find that South Atlantic rifting is predicted to develop a strong southward asymmetry in its distribution of seaward dipping reflectors and associated anomalous relief with respect to the Tristan Plume that “drove” this volcanic rifted margin, and that the region where plume material drains into the rift should experience long-lived uplift during rifting—both as observed. We conclude that a mantle plume is still needed to source the anomalously hot sublithospheric material that generates a volcanic rifted margin, but lateral along-rift flow from this plume, not a broad starting plume head, is what controls when and where a volcanic rifted margin will form.

The accurate determination of factor of safety is important to find out the stability of slopes. Out of the many factors which are responsible for slope failure in hilly areas continuous rainfall, particularly, is one of the major important factor responsible for triggering landslide. Slope is an exposed ground surface that stands at an angle with the horizontal. In this study, a part of the hill of Haflong, the head quarter of Dima Hasao district in the state of Assam, India are chosen. Two types of transient analysis i.e., uncoupled analysis and coupled analysis were carried out. The coupled analysis considers the deformation of the soil surface with time when rain water passes through the soil mass. Three slope angles 30°, 45° and 90° were considered for both the case. The results shows that the factor of safety decreases with increase in the period of rainfall and slope angle, whereas the factor of safety increases slightly during coupled analysis which is due to the combined effect of deformation and seepage.

Papers devoted to chalk-related topics have varied in frequency since the foundation of a geological society in Yorkshire. There have been contributions from vicars, corn merchants, a wallpaper manufacturer, a corset maker and a car salesman, as well as academics and professional geologists. Many early ideas have become established. Indeed, the concept of a Chalk Group Northern Province was suggested by the Reverend J.F. Blake as early as 1878. The keen observation and painstaking recording of other early workers such as Lamplugh on Flamborough Head were continued in the late twentieth century by, for example, Whitham and Mitchell, and the advent of modern technology enabled new dimensions of study. Following a ‘dark age’ of very few contributions, a 1978 publication, though short, finally proposed an accepted lithostratigraphy for the northern chalk that is distinct from that of the south, and in so doing became what might be considered a milestone paper. This ‘renaissance’ bloomed into a ‘golden age’; North Sea activities, advanced technology and a rekindling of interest in chalk stratigraphy and palaeontology all contributed to the publication of a spate of papers. Exactly 50% of all papers and over 50% of all authors involved were published between 1987 and the present day.

Captive-rearing conservation programs focus primarily on maximizing postrelease survival. Survival increases with size in a variety of taxa, often leading to the use of enhanced size as a means to minimize postrelease losses. Head-starting is a specific captive-rearing approach used to accelerate growth in captivity prior to release in the wild. We explored the effect of size at release, among other potential factors, on postrelease survival in head-started Mojave desert tortoises Gopherus agassizii. Juvenile tortoises were reared for different durations of captivity (2–7 y) and under varying husbandry protocols, resulting in a wide range of juvenile sizes (68–145 mm midline carapace length) at release. We released all animals (n = 78) in the Mojave National Preserve, California, United States, on 25 September 2018. Release size and surface activity were the only significant predictors of fate during the first year postrelease. Larger sized head-starts had higher predicted survival rates when compared with smaller individuals. This trend was also observed in animals of the same age but reared under different protocols, suggesting that accelerating the growth of head-started tortoises may increase efficiency of head-starting programs without decreasing postrelease success. Excluding five missing animals, released head-starts had 82.2% survival in their first year postrelease (September 2018–September 2019), with all mortalities resulting from predation. No animals with >90-mm midline carapace length were predated by ravens. Our findings suggest the utility of head-starting may be substantially improved by incorporating indoor rearing to accelerate growth. Target release size for head-started chelonians will vary among head-start programs based on release site conditions and project-specific constraints.

Oil spillage occurrences are due to wars, accidents, drilling, storage, natural disasters, and rapid industrialization, which lead to huge amounts of waste discharge into adjacent areas. Soil contamination is also detrimental to associated structures and foundations. Therefore, in this research, experimental and numerical studies on laterally loaded piles near an oil-contaminated sand slope were conducted to estimate the ultimate lateral capacity, lateral displacement, and maximum bending moment of a single pile embedded in contaminated and uncontaminated sand slope. To simulate the contamination content as in field conditions, preparation of oil-contaminated layers of sandy soil was performed by blending clean sand samples with heavy motor oil at proportions of 0–6% of the dried weight of soil. These studies were performed by varying the contaminated sand layer thickness (LC), oil content (O.C), pile slenderness ratio (LP/DP) and distance from the slope crest (X) to the pile head. The results demonstrated a considerable reduction in the friction angle (O) with increasing oil content. Therefore, the ultimate horizontal load (Hu) of the pile also reduced. Moreover, the raise in the thickness of oil-contaminated sandy soil layer (LC) has resulted in an increment in the lateral movement of the pile (y) and a reduction in the ultimate horizontal load (Hu). When the proportion of the oil content increased to 2% over that in clean sand, the maximum bending moment raised by about 11%. In addition, a good consistency between the numerical analysis and experimental tests was observed.

The Colca Valley in the Central Andes is a region characterized by the occurrence of large slow-moving landslides and a high level of seismic activity. In this study, we aimed to determine passive and active tectonic control on the formation of selected five large landslides in the Colca Valley and to assess geohazard associated with these features. For that purpose, we performed a post-landslide field survey, applied remote sensing techniques, and obtained eyewitness accounts. Recently, the need to understand mass movement processes in this region is even higher due to the establishment of the Colca y Volcanes de Andagua Geopark (Colca and Andagua Volcanoes Geopark). Our results suggest that the studied landslides usually represent a complex failure mechanism, dominated by translational sliding or rotational displacements, commonly associated with the formation of horst-and-graben like structures. We found a spatial correlation between the distribution of landslides and inherited fault network. The head scarps appear to be limited by the WNW- to NW-striking faults, whereas the lateral extent of some of the reported features seems to be connected with the NNE-striking normal faults, common in both, the Mesozoic strata and the Pleistocene-Holocene deposits.

The article introduces the materials of the archaeological excavations of the Dagestan-Georgian archaeological joint expedition on the identified Khunzakh burial ground in 1978-1979, located in the villages. Khunzakh, on the Khunzakh plateau (Republic of Dagestan). The hunzakh plateau is the Central part of the medieval state formations of Sarir and then the Avar Kingdom, which were the most important Christian centers of the Eastern Caucasus in the IX-XIII centuries.As a result of the work carried out, 11 burials were identified, Dating from the IX-XV centuries. All burials were covered with a cultural layer containing archaeological material of the XI-XIII centuries. The identified burials represent three types of funerary structures: 1) an elongated pit of sub-rectangular shape with rounded corners or elongated-oval shape; 2) elongated sub-rectangular pits, slightly tapering to the end North-Eastern wall (in the "legs"), with ledges-shoulders along the side longitudinal walls and with a sketch of their small stones above the pit; 3) elongated sub-rectangular pits, slightly tapering to the end North-Eastern wall (in the "legs"), with ledges-hangers around the perimeter of the pit. Ledges-hangers, obviously, were used for installation of overlappings from stone slabs or wooden planks. The funeral rite is generally monotonous and is characterized by the placement of corpses in elongated pits carved into the rock, with orientation along the Central axis along the line SVV-SWZ, with the position of the deceased stretched out on his back, head in the Western sector, more precisely on the SWZ, the absence of burial equipment. The main features of the funeral rite and Dating of the burial ground allow us to refer it to the number of early Christian monuments of Sarir and consider it as a monument reflecting the process of Christianization of the population of medieval Hunzakh.

Spring and summer are when many environmental scientists normally head into the field to collect data. That’s when it’s safe to summit a glacier high in the mountains to retrieve ice cores. It’s wh...

The classification of hunter-gatherer societies as immediate-return or delayed-return offers a framework to explore variation in their adaptive strategies. Immediate-return societies would have evi...

Shestovitsa archaeological complex consists of the hill-fort, the upper town, the lower city and of the large mound necropolis, which D. Blifeld divided into six mound groups. Burial mounds have been investigated since 1920’s. More than 160 of them have already been excavated till nowadays. In 2017, scientific workers of the Institute of Archaeology of the National Academy of Sciences of Ukraine took a new detailed plan of the necropolis, where the investigated and remaining mounds were identified. In total, the remains of 20 embankments were counted in the third mound group. The third mound group of the Shestovitsa necropolis is situated in the Dibrova boundary 750 m to the west from the hill-fort Korovel, at a low elevation, which in ancient times was washed by a small stream of the old channel of the Desna River. Two mound embankments in the northern part of the third mound group were excavated by Ukrainian-Polish archaeological expedition in 2018. Burial mounds were investigated together, their total area of the excavation covered 220 m2. The remains of 12th century inlet burial, which was located in the upper part in the center of the embankment, were investigated in the first mound situated in the northern part of the excavation. The skeleton belonged to a teenager and preserved partially. No related equipment or traces of the grave pit were fixed. The burial of 10th century was not found. There was a mound ditch around the embankment. The diameter of the mound was 7.0 × 9.0 m. Fragments of 12th century ceramics were found in the western part of the embankment and partially in the upper layers of the ditch filling. The mound no. 2 was situated to the south of the previous one. Before the beginning of the investigations it was 0.39 m high. The mound had an oval shape and was extended from west to east by 7.2 × 8.2 m. Man’s burial in a grave pit with the head oriented to the west, was found in it. The skeleton laid in anatomical order with legs bent at the knees. There was an iron knife near the right thigh bone of the buried, and an iron octagonal tip of the knobstick under his right knee. The diameter of the mound was 9.5 × 10 m. Thus, in the 2018 season, two burial mounds in the third group of the Shestovitsa archaeological complex were excavated. The burial of the man of 10th century and the inlet burial of 12th century in one of 10th century mounds, where the burial was absent or not preserved, were found here.

The stream is still quiet, and we guide along through a strange, weird, grand region. The landscape everywhere, away from the river, is of rock—cliffs of rock, tables of rock, plateaus of rock, terraces of rock, crags of rock—ten thousand strangely carved forms; rocks everywhere, and no vegetation, no soil, no sand. In long, gentle curves the river winds about these rocks. These are the words Major John Wesley Powell used to describe what is called Stillwater Canyon along the Green River on July 17, 1869, on his way to the Grand Canyon during his famous journey exploring the canyons of the Colorado River and its tributaries (Powell, 1895). This same region is spectacularly displayedfrom the Green River Overlook in the Island in the Sky District of Canyonlands National Park. The exposed rocks consist of Early Permian- (299 million years ago [Ma]) through Early Jurassic-age (176 Ma) rock layers that were uplifted and subjected to massive erosion. Changes in the color, thickness, and composition ofthe rock layers and erosive work of running water and gravity (i.e., mass wasting) created the magnificent landscape seen at the overlook today. The primitive and remote Maze District of Canyonlands National Park is the area west of the Green River. Prominent features viewed in the Maze District from the Green River Overlook include Ekker Butte, Turks Head, Elaterite Butte, and the Orange Cliffs (figure 2). On a clear day, the 11,000-foot (3350 m), Henry Mountains, which are cored by volcanic remnants (laccoliths) can be seen to the southwest. The Green River Overlook is one of Utah’s most iconic views, often appearing on book covers, scenic calendars, and postcards, and therefore it is fitting as a geosite for its beauty and the exposures of rocks that so much impressed John Wesley Powell over 150 years ago.

The research aimed to study the effect of groin application to erosion at the shoreline. The method utilized the bathymetry and topography data of north beach of Balongan, West Java. Modeling of the shoreline change due to groin installment used software called GENESIS. Based on analysis result, it is found that the significant wave direction comes from the southeast with significant wave height of 1,18 meters and surf zone width of 140 meters. It is concluded that at research area of north beach of west Java, I-groin with length of 70 meters and T head groin of 60 meters in long T-groin effectively overcome erosion and advance the coastline by 10786,62 m2 or in average 6,3 meters.

A field monitoring system was established in an active river bank landslide in the Three Gorges area, China, and a consecutive monitoring for about 5 years were conducted to understand the displacement characteristics of flexible piles and the surrounding soil. It was found that piles deformed elastically under reservoir operation, and the soil in front of piles was gradually separated from piles. The movement of the pile heads exceeded that of the soil between and behind piles. This phenomenon was further studied by a large-scale physical model test to gain insights into the pile-soil interaction. The displacement relationship between pile heads and the surrounding soil is in good agreement with the field data. The physical model test shows that the deformation process of pile-reinforced landslides can be divided into two stages: firstly, when the piles head movement exceeds soil movement, the soil arching is mainly affected by the deflection of the piles, the arches between and behind piles bent upwards; but when the soil movement exceeds piles head movement, the arches near the upslope and downslope bent downwards and upwards, respectively. Furthermore, the different deformation of two adjacent piles and the pile stiffness influenced the arch’s shape and formation; the flexible piles exhibit great coordinated deformation with the landslide, and caused the soil arch on the downslope.

Made available in DSpace on 2020-12-10T19:55:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) A new species of Brachychalcinus is described from the Rio Trombetas basin, Brazil. It differs from congeners by possessing a conspicuous rounded second humeral spot. Additionally, our new species differs from Brachychalcinus nummus, B. orbicularis and B. reisi by having a higher number of branched dorsal-fin rays, and from Brachychalcinus parnaibae by having a lower head depth. Univ Estadual Paulista, Dept Morfol, Lab Biol & Genet Peixes, R Prof Dr Antonio CW Zanin S-N, BR-18618689 Sao Paulo, SP, Brazil Univ Estadual Paulista, Lab Ictiol, Setor Zool, Campus Botucatu, Sao Paulo, Brazil Univ Estadual Paulista, Dept Morfol, Lab Biol & Genet Peixes, R Prof Dr Antonio CW Zanin S-N, BR-18618689 Sao Paulo, SP, Brazil Univ Estadual Paulista, Lab Ictiol, Setor Zool, Campus Botucatu, Sao Paulo, Brazil

Quite rare archaeological finds in Western Siberia – the combs with horse head are analyzed in the paper. Their study is based on comparative materials of European Russia. Accounting for archaeological finds and museum exhibits allows the author to develop a typology of the combs with horse head, as well as to determine the chronology of their existence. The shape of the product, on the basis of which three types are distinguished is considered as the leading sign. According to the author, it can be considered proven that the combs with horse head beyond the Urals appeared with the arrival of the Russian population. Based on the typology performed, it can be assumed that in the 16th – 19th centuries there were two penetrating streams of the combs with horse head in Western Siberia. The first stream occurred in the 16th – 17th centuries, when combs of the first and second types appeared here. This penetration can be conventionally called the «North Russian». The second penetrating stream which was characterized by the third type of the comb-pendants took place to the 19th century. The author believes that according to a number of signs, the second stream of penetration could be a consequence of the Volga region influence.

In the course of a scientific cooperation between the German Mummy Project at the Reiss-Engelhorn-Museen, Mannheim (Germany) and the Musée National d'Histoire et d'Art Luxembourg (Luxembourg), an ancient Egyptian mummy head was analyzed using a multidisciplinary approach including radiocarbon dating, ultra-high resolution computed tomography, physical anthropology, forensic medicine and Egyptology. Dated to the Roman Period, the mummy head belonged to an upper-class woman between 25 and 35 years of age. Computed tomography revealed a lethal blunt force trauma affecting the dorsal parts of the parietal bones, below the intact overlaying soft tissue. Moreover, ancient medical treatment was evidenced through localized shaving of the hair on the affected area, which indicates that efforts have been made to keep the woman alive. This astonishing example of homicide demonstrates the enormous scientific benefit brought by the multidisciplinary investigation of mummified bodies and body parts, and sheds light on life, death and medical care of a woman from Roman Period Egypt.

Toad bones, sometimes occurring in great numbers in pit features and other contexts in Native American village and mound sites in the Appalachian Summit, have been interpreted as evidence that toads were consumed, used for their purportedly hallucinogenic toad venom, placed as ritual deposits, or naturally entrapped/intrusive. A paucity or lack of bones of the head in some contexts is suggestive of decapitation and consumption of toads. Alternatively, bones of the head may be less preservable, recoverable, or identifiable. This study examines toad remains on Appalachian Summit late precontact and contact period sites, reviews previous experimentation, and presents a new experimental study undertaken to identify agencies of accumulation. We propose that toads were regularly consumed and possibly as part of ritualized events associated with village and mound construction. The temporal and geographic restriction of this practice to the Pisgah and Qualla phases of the Appalachian Summit suggests subsistence ethnicity as alluded to in historical accounts.

Gully erosion is the most active hydro-geomorphological phenomenon in the continental areas due to the high erosion rates triggered by the gully system. Monitoring and modelling gully development and gully distribution will contribute to understand landforms evolution and risk assessment. The purpose of the current research is to model head-cut gully erosion susceptibility (HCGES) using support vector machine (SVM), random forest (RF) and novel ensemble model of random forest with four Oblique methods (Logistic Regression, Ridge Regression, Partial least squares (PLS) and Support vector machine (SVM)) (hereafter called ensemble ORF) data mining models in Fareghan watershed, Hormozghan province, Iran. For this purpose, 14 variables influencing the gully development, were prepared and 145 head-cut gully erosion locations were identified in the study area. The efficiency of SVM, RF, ensemble ORF were evaluated based on receiver operating characteristic (ROC), the results have shown that all these three models are highly accurate and robust in predicting the head-cut gully erosion susceptibility zones. The results of the models were evaluated based on the area under the receiver operatic characteristic curve (AUC) in the validation stage presented that the efficiency of these models are 0.91, 0.94, and 0.96, respectively. Altitude and distance from the road in all three models were more important than other variables. The findings of this research will contribute to develop gully control strategies and to prevent the gully initiation where gully erosion is more susceptible.

Along the recently evacuated shores of the retreating Dead Sea black mud deposits have been exposed and hence subjected to head ward erosion resulting in landslides and land collapses threatening herewith the infrastructure in the area. The geotechnical and mineralogical characterization of the black mud show the presence of a variety of clays including smectite, kaolinite, illite, montmorollinite and muscovite with a natural water content near the liquid limit. These geotechnical and mineralogical properties indicate that the mud is prone to rapid erosion and sliding, which actually hit the area and have until now caused damages and degrading topography and geology in the area. The study also refers the origin of the black mud and its organic content to the erosion and deposition of Upper Cretaceous-Tertiary oil shale deposits formerly covering the whole surrounding areas of the Dead Sea. The study suggests engineering solutions to the geologic degradation processes in the area, before further damage to the infrastructure takes place.

Hydro-abrasive erosion caused by suspended sediments is a severe issue leading to frequent generation losses and failure of hydropower components especially in geologically young mountains like the Himalayas. To study the erosion behaviour of different materials under the same erosive and hydraulic conditions, experiments were performed simultaneously with different range of velocity, duration of exposure, sediment size, and concentration on a 1:8 down scaled Pelton buckets from an Indian hydropower plant (HPP) located in Himalayas. This work extends the research of Padhy and Saini (2009) for application in Pelton turbines fabricated from 6 materials such as 3 kinds of steel, 2 kinds of coatings and bronze for head up to 200 m. The values of sediment concentration for the tests were 500, 1500 and 3000 ppm, values mostly found in the HPPs. The developed erosion models were used to predict the erosion of the Pelton buckets from the study plant and are useful for proper planning of preventive measures and operation of the HPPs.

The article presents the results of hydroecological modeling of variations of phytoplankton biomass, biogenic substances, and dissolved oxygen concentration in a reach of the Lower Don within the designed Bagaevskoe Reservoir at different variants of its design levels and possible natural and anthropogenic impacts. Water releases from the Tsimlyansk Hydropower System are shown to have the key role in the formation of the environmental conditions of the designed reservoir.