Cubic Meters Of Rock Research Articles

Geodynamic processes in the territory of the Svidovets mountain massif of the Ukrainian Carpathians (in the zone of the planned creation of a tourist and recreation complex)

The purpose of the research is a comprehensive analysis of various geodynamic natural processes on the territory of the Svydovets mountain massif of the Ukrainian Carpathians - the zone of the planned creation of a tourist and recreational complex for the development of a program for their further detailed study in the area of the planned activity (PА). The methodology includes a comprehensive analysis of the manifestation and course of dangerous geodynamic processes based on source information and individual studies of the authors. The Svydovets massif is located within the Central Synclinal Zone of the Carpathians, which is composed of Eocene and Oligocene chalk flysch. The highest part of the ridge with the southwestern and southern slopes and peaks Chorna Kleva (1720 m), Ruska (1678 m), Bratkivska (1788 m), Gropa (1759 m) is confined to the territory of the PA. The massif is characterized by a complex division of thrust structural slices of the Porkuletsky, Duklyansky and Chornohirsky nappes (covers). There are very steep north-eastern and gentle south-western slopes. The main forms of relief that characterize relict glacial relief are cirques, glacial valleys, rocky cirque ridges, steep rocky walls of cirques, moraine deposits, etc. On the southern and northern macroslopes of the Bratkivska Range, stone placers have been preserved from the Ice Age. Slope placers on the south-western macroslopes (areas of the Gropa, Ruska and Chorna Kleva mountains) are potentially dangerous for the formation of landslides and screes. Activities on the middle and lower slopes require special attention, where there is a possible negative impact during the construction of roads, felling and transportation of forest. Earthquakes, mudslides, landslides, debris flows, landslides, and avalanches are among the most dangerous processes on the territory of the PA. Earthquakes are of minor magnitude. Landslides and ossips are common on the northern and eastern slopes of the Svydovets massif, including on the watersheds and southwestern slopes of the Bratkivsky ridge. They are confined to slopes of considerable steepness (more than 35°) and occupy a small area. Small landslides with a volume of several tens of cubic meters of rock predominate, and rockfalls with fragments of 1-1.5 m in size. Landslide processes are widespread in the Ukrainian Carpathians, in particular within the PA in the Krosno tectonic subzone, which covers the latitudinal segment of the upper basin of the Chorna Tysza and the Yasinya syncline. Manifestations of avalanche activity on the Svydovets massif occupy one of the first places in the Ukrainian Carpathians along with the Chornohora and Borzhava ridges. The length of avalanches can be more than 1.5 km, and the volumes of avalanches - more than 400,000 m³. The Bratkivsky ridge is a non-avalanche active area, while the northern slope of the Svydovets massif and the Chorna Tysza valley are avalanche- dangerous. Considering that the PA territory covers mainly the southern slope of the Bratkivsky ridge, the avalanche danger is insignificant. Scientific novelty. The manifestation and activity of various dangerous geodynamic processes within the territory of the Svydovets massif - a zone of possible anthropogenic impact on the environment as a result of PA for the development of the ski resort - are analyzed in detail. Practical significance. The results of the research will help to the future developer of the ski tourist and recreational complex to develop a program for further detailed study of dangerous natural phenomena at the planned construction site, and can be partially used in the implementation of the Environmental Impact Assessment Report for PA. They also inform the public about the possible impact of PA on the environment.

Wear and cutting temperature of thermally stable diamond composite tipped pick in hard rock cutting

Thermally stable diamond composite (TSDC) material has been proposed as a replacement for tungsten carbide (WC) as the cutting-tip material for hard rock cutting due to its high wear resistance and thermal stability. As a new type of rock cutting tool, monitoring the wear and cutting temperature of TSDC cutting tips is of great significance in assessing the application of these picks in the mining and construction industries. A series of rock cutting tests was carried out using TSDC tipped picks. The cutting parameters for these tests were similar to those used in industrial production. The wear on the TSDC tip, assessed as the volume loss (mm3) from the tip per cubic meter of rock removed, was measured by a 3D laser scanner. The temperature of the TSDC tip as it exited the rock was recorded by a high framerate, infrared camera (FLIR X6801). The wear and cutting temperatures of TSDC-tipped picks were compared with conventional WC picks under the same testing conditions. The relationships between wear, cutting temperature and cutting parameters of both materials were analysed and discussed.

Blast resistance of rocks–framework for the blastability classification of solid materials

The rock blastability analysis reveals that the common blastability characteristic of rocks, namely, powder factor per fragmentation of 1 cubic meter of rock, is an indirect estimate of blast resistance. The review of the existing rock blastability classifications finds out that the comparison of these classifications is impossible due to different definitions of rock blastability, as the powder factor depends, ambiguously, on the rock hardness, explosion yield and blasting conditions. Explosibility of rocks is also often estimated as function of rock hardness factor on Protodyakonov’s scale. In this case, it is assumed that hard rocks are more difficultly blastbale than soft rocks with smaller value of hardness. In reality hard but brittle rocks, other things being equal, have smaller resistance to blasting and produce better fragmentation as against weaker clayey rocks. This is connected with sudden attenuation of blast-induced seismic waves in loose clayey rocks. The proposed method allows higher accuracy of rock blast resistance estimate thanks to inclusion of rock characteristics reflective of rock blastability. It s found that blast resistance of solids, including rocks, depends on the material constitution, structure and texture of a material. The blast resistance value is minimal in low-density and brittle rocks, for instance, coal, with low strength, and is maximal in dense and more plastic rocks. The proposed rock blastability classification grounded on the mechanics-based blast resistance index enables powder factor control and enhancement of blasting efficiency in surface and underground ore and coal mines.

Cutter change time and cutter consumption for rock TBMs

This paper discusses common methodologies used in the prediction of cutter change time (the average time required for changing a cutter on the cutter head) and cutter consumption (the average number of cutters worn out for the excavation of 1000 cubic meter of rock) and highlights some potential pitfalls in the process. For this purpose, the prediction capabilities of these methods are discussed and their validity is examined using detailed data from many tunnels from around the world. The results of the statistical analyses and comparative studies show that in most cases, the NTNU model underestimates cutter change time. The average cutter change time is approximately 66 min for different cutter sizes and there is a minimal difference between corresponding values of the large versus small cutters. A new cutter change time model is also developed using a statistical analysis of a database of 50 TBM projects’ records based on the TBM penetration rate and quartz content of the rock. Analysis of the cutter consumption information of several tunnel projects has revealed that the available models for the estimation of this parameter require some revisions in the structure of their formulas. A new cutter consumption model is also developed based on a statistical analysis of a database of 135 TBM projects’ records. The results show the proposed new model’s estimates are in good agreement with the actual values with a high coefficient of determination (78%). The outcomes of this paper can improve rock TBMs’ performance and project planning evaluation especially for the early stage of a tunneling project.

Towards ‘green’ geothermal energy: Co-mineralization of carbon and sulfur in geothermal reservoirs

Geothermal fluid utilization is considered one of the green energy sources. Yet, mitigation strategies must be applied to reduce the associated pollutants like carbon dioxide (CO2) and toxic hydrogen sulfide (H2S) emissions. One suggested method is the re-injection of the two gases back into the geothermal reservoir wherein carbon and sulfur are expected to mineralize naturally for a long-term underground storage. However, CO2 and H2S mineralization rates for natural systems are not well defined. To address the feasibility of such sequestration, experiments were conducted at 250 °C for several reservoir rock types, ranging from basaltic to silicic. Analysis of solution composition and secondary mineralogy confirmed the precipitation of Fe-Ca carbonates and Fe sulfide for all the rocks within days. The measured mineralization rates indicate that ∼0.2–0.5 t of CO2, and ∼0.03–0.05 t of H2S can be sequestrated annually per cubic meter of rock, depending on reservoir lithology and surface area. Calculations show that a total rock sequestration capacity of ∼0.03 km3 would be sufficient to store the annual world CO2 and H2S geothermal emissions. These findings indicate efficient abatement of CO2 and H2S at field conditions, confirming the strategy potential for at least the typical 50 years-lifetime of geothermal power plants.

Catastrophic landslide of medieval Portonovo (Ancona, Italy)

This paper is a case study about a natural catastrophic event that caused a human disaster in the medieval Benedictine enclave of Santa Maria in Portonovo—a large landslide involving some 5 million cubic meters of rock, which suddenly collapsed from the northeastern flank of the Monte Conero anticline hurling down from 400 m elevation over the littoral zone of the Portonovo bay, ∼9 km south of the Adriatic port city of Ancona. This landslide is the largest of the Conero Riviera, a 16-km-long, seismically active high coast with cliffs overhanging directly over the sea, which is therefore particularly prone to landsliding. While the landslide risk along the Conero Riviera has been evaluated by the local municipal authority, the risk in the Portonovo bay, a very popular beach resort, has been somewhat underestimated inasmuch as the huge landslide was previously considered, by geologists and geoengineers, to be a prehistoric event and therefore unimportant in the context of prevention plans aimed at assessing the hydrogeological instability of this area. We approached our study by surveying the area of the landslide using detailed ground truthing and geological mapping, and defining the geomorphology and lithologic composition of the landslide from head to toe. Radiocarbon dating of neritic mollusk shells from the autochthonous sediments underlying the landslide toe, which were retrieved from two drill cores from the toe of the landslide deposit, indicated that the landslide occurred in historical times, contrary to common belief that it occurred in prehistory. We then reconstructed the history of environmental changes of the Portonovo bay prior to, and subsequent to the landslide event using a detailed facies analysis of these two drill cores and of a third one drilled through the center of the landslide body. Written documentation about the medieval history of Portonovo, including an old map of the northeastern face of Monte Conero, which shows no evidence for the landslide, suggests that it occurred in the early fourteenth century, destroyed the strategic harbor of Novo Porto, and caused the definitive abandonment of the three-centuries-old Benedictine abbey of Santa Maria in A.D. 1320. The lithologic, structural, and rheologic setting of the steep northeastern flank of the Monte Conero anticline provided the predisposition for the huge medieval landslide, a structural setting possibly weakened by unusually intense seismic activity that affected the Conero Riviera from the late thirteenth to the early fourteenth centuries. The same structural and lithologic settings are found today on the slopes adjacent to the western side of the medieval detachment scar, thus representing a serious threat for the stability of the area and a high risk for imminent large landsliding, which may have grave consequences for present-day infrastructure and inhabitants of the popular Portonovo beach resort. Therefore, we present this work on the giant Portonovo landslide as an example of how interdisciplinary scientific investigation on hydrogeologically unstable areas may help in preventing human disasters.

The role of fluid phase immiscibility in quartz dissolution and precipitation in sub-seafloor hydrothermal systems

A numerical model describing quartz dissolution and precipitation in sub-seafloor hydrothermal systems has been developed that documents the effects of retrograde quartz solubility and fluid phase immiscibility on the transport and deposition of silica in this environment. Rates of dissolution and precipitation increase with increasing permeability and with increasing maximum temperature at the base of the system. At the most optimal conditions considered in this study (425°C, permeability of 10−13m2), quartz is precipitated at rates up to 10−6mol/m3·s (equivalent to 700cm3 of quartz per cubic meter of rock per year). Immiscibility at the base of the system creates a zone in which large amounts of quartz precipitate as a result of phase separation. The high rate of quartz precipitation at the one-fluid-phase/two-fluid phase boundary is consistent with the location of highly silicified zones found beneath volcanogenic massive sulfide deposits. Rapid quartz deposition at this boundary may affect the heat transfer efficiency at the base of the upflow zone and may contribute to immobilizing the brine layer so that it does not rise towards the surface. The process of rapid quartz precipitation at the base of the upflow zone, and its effects on the dynamics of these systems, is only observed under conditions of liquid–vapor immiscibility.

Landslide alarm

Just after midnight on 8 August, a massive landslide sent nearly 2 million cubic meters of rock and mud hurtling through several towns in Zhouqu County, China. The natural disaster killed more than 1500 people in the county, which sits in a valley between two mountains in Gansu Province. Three months later, more than 250 people were still unaccounted for. Though their breakthrough is too late for the Zhouqu disaster, researchers at Loughborough University, in England, reported in October that they have developed an electronic system that can warn of an impending landslide by picking up the telltale sounds of shifting earth.

A geologic study of the Juan del Grijalva landslide, the most important mass movement during the last century in Mexico

On November 4th 2007, along the Grijalva River in the state of Chiapas, Mexico, has occurred one of the largest landslides ever known. This landslide, known as Juan del Grijalva, destroyed the town of the same name, killing 20 people, and moved 55 million cubic meters of rock and debris down slope to completely block the Grijalva River. In order to understand the characteristics and factors that triggered the Juan del Grijalva landslide, geologic studies were conducted at the site. The results indicate that the landslide was composed of a lithologic sequence of thin-bedded shales and thin to medium-thick-bedded sandstones. This was faulted into several blocks dipping in the same sense as the mass movement. The main triggering factor was the increment of the pore pressure into the lithologic unit due to water saturation after 5 days of heavy rain before the incident. According to records from the last century, the Juan del Grijalva mass movement represents one of the largest mass movements recorded all over the world. The risk conditions of the area after the landslide lead to the rapid construction of an artificial channel to drain the accumulating mass of water upstream and therefore prevent a future catastrophic inundation down stream.

Development of Emission Factors for Quantification of Blasting Dust at Surface

Environmental impact assessment (EIA) and environmental management plan (EMP) is a statutory requirement for execution of new mining projects or for expansion of the operating projects. For this purpose, quantification of blasting dust emission is required. This can be done by developing emission factors for blasting. The concept is similar to that of specific charge in blasting. For mining operations other than blasting, quantification of dust can be done using emis- sion factors. Emission estimation techniques are very limited for blasting. In this study, the emission factors were de- veloped by carrying out a detailed field study at one of the largest opencast coal mines of India in all four seasons. Da- ta on atmospheric and meteorological conditions were generated by installing sodar and automatic weather station at the mine site. Respirable dust samplers were installed for monitoring of the dust emitted during coal or overburden bench blasting. Emission factors for dust concentrations were developed in gram per cubic meter of rock excavated. The developed emission factors were used to estimate dust emissions for adjacent mines due to similarity in mining and meteorological conditions. Seasonal variations in moisture contents in benches, where dust was monitored, indicated the lowest emission factors in monsoon due to high moisture in the bench materials. Similar field studies were also conducted at another coalfield of India for two seasons. It was found that the emission factors are site-specific.

Oxidation of CH 4 to CO 2 and H 2O by chloritization of detrital biotite at 270 ± 5 °C in the external part of the Central Alps, Switzerland

The upper end of the CH 4-zone in the External part of the Central Alps of Switzerland results from an oxidation reaction of methane into water and carbon dioxide at 270 ± 5 °C [Tarantola, A., Mullis, J., Vennemann, T., Dubessy, J., de Capitani, C., 2007. Oxidation of methane at the CH 4 / H 2O–(CO 2) transition zone in the external part of the Central Alps, Switzerland: Evidences from stable isotope investigations. Chemical Geology 237, 329–357.]. Petrographic investigations of the North-Helvetic Flysch revealed the presence of detrital biotite, muscovite and chlorite in the CH 4-zone. At the transition from the methane to the water zone, the sudden increase of CO 2 in the fluid is associated with the formation of chlorite and muscovite in replacement of detrital biotite. In the H 2O-zone, biotite is entirely replaced by chlorite-muscovite interlayered stacks. Mössbauer spectroscopy showed a minimum decrease of XFe 3+ from 0.18 to 0.09 within the sheet silicate fraction at the transition from the CH 4- to the H 2O–(CO 2) dominated fluid zone. Detrital biotite of the investigated host rocks incorporates at the same conditions larger amounts of Fe 3+ than chlorite in its structure and XFe 3+ (biotite) > XFe 3+ (new-chlorite) > XFe 3+ (detrital chlorite). The reaction of chloritization of detrital biotite is interpreted as a fluid controlled mineralogical isograde at 270 ± 5 °C, marking the transition from the low to the high grade anchizone, and allowing the oxidation of up to 36 moles of CH 4 per cubic meter of rock.

The environmental risk posed by small dumps of complex arsenic, antimony, nickel and cobalt sulphides

Mine waste dumps sited in the vicinity of mine workings typically consist of fragmented rock masses which in chemical terms may be defined as "complex systems", due to uncertainties in accurately simulating their behaviour, when water or aqueous solutions percolate through them. Remediation of the contamination problems created by abandoned mine dumps concerns many former mining areas from Europe to Africa. These dumps usually range in size from a few hundred thousand up to million cubic meters of rock defined as “waste” but which still contain significant amounts of potentially toxic elements. Although relatively small, they are often densely distributed in the territory impacting on surface and ground-water. This scenario is particularly applicable to the region of Sardinia, Italy, where several small dumps of uncommon sulphide minerals still exist on derelict mine sites. This paper reports on the results of a research project aimed at defining appropriate remedial measures of acid rock drainage. A dump of a Co–Ni–As–Sb complex sulphides mine was investigated and simulated in a laboratory leaching column. The column was irrigated with distilled water and a repetitive behaviour of the polluting elements concentrations in the effluents was observed for each run. Regardless of the campaign duration and the extent of the intervals between tests metal ions concentration peaks (250–50 ppm for Ni, 35–20 ppm for Co, 1.6–0.4 ppm for As, 20–15 ppm for Zn and 0.03–0.002 ppm for Sb) and acidic conditions (pH 2.5–3.5), on resumption of each irrigation, was noticed. As percolation continued, the ion concentrations decreased within the discharge limits after the replacement of only two pore volumes of the column material. This produces the conception that a sufficiently long rainfall period could remediate the polluting effects. Conception contradicted by field experiences: sporadic rainfall events, typical of the region, are not sufficient to completely leach out the metal ions. The repetitive nature of the leaching processes, both quantitatively and qualitatively, can be explained only by the activity of a microflora thriving in the rock mass even during long dry periods. Microbial tests and neutralisation campaigns confirmed this hypothesis and suggested that any effective remediation strategy must take into consideration the interaction between environmental factors with microbiological activities.

Relative stress conditions in an underground pillar, Homestake Mine, Lead, SD

Abstract Personnel from the Spokane Research Center, a division of the national Institute for Occupational Safety and Health (NIOSH), have been investigating the use of three-dimensional seismic tomography to detect hazardous ground conditions and monitor the mechanical integrity of a rock mass. This technique was used to determine relative stress in an underground pillar on the 7400 level of the Homestake Mine, Lead, SD. Low velocities, which are interpreted as identifying areas of low stress, were associated with boreholes, segments of haulageways, and the corner of an adjacent pillar. High velocities, which are interpreted as identifying areas of high stress, were identified in the northeast part of the pillar. High stess can result in enough seismic activity to cause unsafe conditions for miners, such as ground falls. The importance of identifying highly stressed areas in a pillar is that engineers can evaluate the mining cycle and determine the best approach to excavating such areas, or use destressing or preconditioning techniques to relieve the stress. In the field of rock mechanics, the benefits of using three-dimensional seismic tomography to identify high stress are that (1) the technology is noninvasive, (2) it is reliable, (3) it allows a series of surveys to be conducted over time, (4) it is less expensive than conventional methods, (5) it is time efficient, and (6) it allows researchers to evaluate and monitor a large rock mass (as much as 2 million cubic meters of rock)

Post-blast bench block stability assessment

Personnel from the Spokane Research Center, a division of the national Institute for Occupational Safety and Health (NIOSH), have been investigating the use of three-dimensional seismic tomography to detect hazardous ground conditions and monitor the mechanical integrity of a rock mass. This technique was used to determine relative stress in an underground pillar on the 7400 level of the Homestake Mine, Lead, SD. Low velocities, which are interpreted as identifying areas of low stress, were associated with boreholes, segments of haulageways, and the corner of an adjacent pillar. High velocities, which are interpreted as identifying areas of high stress, were identified in the northeast part of the pillar. High stess can result in enough seismic activity to cause unsafe conditions for miners, such as ground falls. The importance of identifying highly stressed areas in a pillar is that engineers can evaluate the mining cycle and determine the best approach to excavating such areas, or use destressing or preconditioning techniques to relieve the stress. In the field of rock mechanics, the benefits of using three-dimensional seismic tomography to identify high stress are that (1) the technology is noninvasive, (2) it is reliable, (3) it allows a series of surveys to be conducted over time, (4) it is less expensive than conventional methods, (5) it is time efficient, and (6) it allows researchers to evaluate and monitor a large rock mass (as much as 2 million cubic meters of rock)

Use of the probabilistic method of calculating stability when designing rock slopes

1. At present rock slopes are usually designed on the basis of the most unfavorable (of those possible) arrangement of potential shear joints in the investigated mass and without consideration of the probability of the presence of joints of such orientation in it. 2. A new method is proposed here for calculating the stability of rock slopes based on the use of a statistical probabilistic method of processing the measurements of orientations of potential shear joints and taking as the criterion of stability of slopes their reliability value. 3. The practical use of the method when designing the rock slopes of foundation pits of the Southern Ukraine power complex showed the advantages and prospects of the probabilistic approach to estimation of the stability of masses. In particular, use of the method made it possible to design some steeper slopes, which as a whole for the complex will permit avoiding additional excavation of tens of thousands (potentially as much as 160,000) of cubic meters of rock. 4. The results of calculating slope stability for various values of the hydrostatic pressure indicate the need for special investigations (e.g., on an electrohydrodynamic analogue) to determine the shape of the line of seepage in masses and the expediency of refining this line during excavation works.

Geochemistry of Hydrothermal Chlorite Replacing Igneous Biotite

AbstractHydrothermal chlorite replaces igneous biotite in the Gold Hill, Utah, quartz monzonite. Chemical compositions of coexisting biotite and chlorite determined by electron microprobe and wet chemical methods were used to evaluate chemical mass transfer during the alteration process. The mole ratio Mg/(Mg + Fe) varies from 0.52 to 0.65 in the chlorite and from 0.51 to 0.60 in the parent biotite. The Mg content of the chlorite decreases systematically with increase in the volume percent replacement of biotite. Homogenization temperatures of fluid inclusions in nearby quartz microveinlets indicate that the chloritic alteration took place at approximately 200°C.Textural relationships suggest that the alteration of biotite to chlorite is isovolumetric, but a comparison of mineral compositions and mineral assemblages with phase diagrams in which Al or volume are conserved among solid phases suggests that the chlorite compositions are best explained as a function of reaction progress in an Al-conservative system. The chlorite composition changes in response to changes in solution composition produced by the dissolution of successive small amounts of biotite. Representative mass balance for the alteration of all of the biotite to chlorite in 1 m3 of rock containing 336 moles of biotite indicates that 74 moles of Mg, 35 moles of Fe3+, 420 moles of H+, and 2 moles of Mn are added to the rock and that 311 moles of K, 54 moles of Fe2+, 76 moles of Ti, 53 moles of F, and 6 moles of Cl are lost to solution. The mass transfer for partially altered biotite is 11 to 188 moles of K, 2 to 46 moles of Ti, 2 to 44 moles of F, and 0.3 to 6 moles of Cl removed per cubic meter of rock and 1 to 26 moles of Fe3+ and 20 to 347 moles of H+ added. The mass transfer of Mg varies from 12 moles added to 32 moles removed per cubic meter of rock depending on mineral composition and extent of replacement.

Control of the stability of the working sides of open pits

In the working of flat-lylng coal seams in complex engineering-geological conditions with tectonic faults, varied structure and bedding with weak interlayers, there are often cases of deformation of sides and benches, and sometimes large landslides leading to catastrophic caving of tens of millions of cubic meters of rock. This kind of deformation has been observed in coal mines in the Primor'e and other coalfields working trough-shaped deposits. In 1969 at the Rettikhovskil mine there was a landslip in the eastern part of the working side, confined to the synclinal dip in the coal seam. The length of the sllp was 520 m and its total area 150,000 m2; its volume was about 5.10 ~ m s . For 15 days the deformation was slow; the rock near the parting crack appreciably subsided and horizontal movements were observed. For a few minutes before the final slip, the horizontal velocity rose sharply and reached the critical value. The side moved rapidly; the vertical drop of the surface within the active pressure prism of the slip was 25 m (Fig. i).

Catastrophic Rock Slide, Mount Huascaran, North-Central Peru, May 31, 1970: GEOLOGIC NOTES

A catastrophic rock slide involving over 2 million cu m of rock roared down the valley of the Llanganuco River, split into two lobes, one of which killed approximately 2,000 people in the town of Rangrahirca and the other killed approximately 19,000 people in the town of Yungay. Many thousands of other rock slides within 100 km of Chimbote resulted in many millions of cubic meters of rock forming scree slopes at the foot of steep hills and mountains. The slide was triggered by an earthquake 85 km away, at a depth of 54 km. In the upper and steepest drop the slide fell and swept as a nearly friction-free unit mass a distance of 14.5 km, a vertical drop of 13,700 ft, in 3 minutes. Over the next 50 km the slide moved as a fluid mass, covering the distance in 2 hours. Deposition from the slide was velocity-dependent.

Sherman Landslide, Alaska

Triggered by the earthquake of 27 March 1964, 3 x 10(7) cubic meters of rock fell 600 meters, then slid at high speed 5 kilometers across the nearly level Sherman glacier near Cordova. The landslide has a number of significant new features in addition to those typical of other large landslides that may have slid on a layer of trapped and compressed air.