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[en] A non-intrusive, seismic subbottom profile survey of pond sediments was conducted on a former U.S.Naval Facility at Argentia, Newfoundland, to characterize the nature and extent of contamination. An IKB Seistec boomer was used in conjunction with C-CORE's HI-DAPT digital data acquisition and processing system and differential GPS system. The survey was successful in locating regions of soft muddy sediments and in determining the thickness of these deposits. Subsurface buried objects, which are potential sources of pollution, were also identified. Intrusive profiling of the sediment was done with a new tool, the Soil Stiffness Probe, which combines two geophysical measurement systems to determine bulk density and shear stiffness. The muddy sediments were found to be highly 'fluidized', indicating that they could be easily removed with a suction dredge. 4 refs., 5 figs
[en] The following subjects were discussed: Rock mechanics, physical properties of rock strata, seismics and seismology, exploration and data processing, geophysical investigations and borehole logs, studies of the earth's crust and shell archaeometry, geotechnics, rock and palaeomagnetism, petrohydraulics, petrophysical studies, electromagnetic probing, geodyanmics. Separate records are available in the database for 14 papers. (RB)
[de]Themen dieser Tagung sind: Petromechanik, physikalische Gesteinseigenschaften, Seismik und Seismologie, Exploration und Datenverarbeitung, geophysikalische Untersuchungsmethoden und Bohrmessungen, Untersuchungen von Erdkruste und -mantel, Archaeometrie, Ingenieurgeophysik, Gesteins- und Palaeomagnetismus, Petrohydraulik, petrophysikalische Untersuchungen, elektromagnetische Sondierungen, Geodynamik. 14 Beitraege wurden einzeln aufgenommen. (RB)
BackgroundOn March 25th, 2015, a rapid landslide occurred upstream of the village of Gessi-Mazzalasino, in the municipality of Scandiano, affecting two buildings.Rapid landslides, due to their high velocity and mobility, can affect large areas and cause extensive damage.Considering the often unpredictable kinematics of landslides, the post-failure behavior has been studied by many authors to predict the landslide runout phase for hazard assessment.
FindingsWith the aim of characterizing the Gessi-Mazzalasino landslide, field surveys were integrated with the results of laboratory tests. The geometric characteristics (thickness, area and volume) and kinematic aspects of the landslide were estimated by using a laser scanning survey and geomorphological data.To model the landslide and obtain its rheological parameters, a back analysis of the event was performed by means of a depth-averaged 3D numerical code called DAN3D. The results of the back analysis of the landslide propagation were validated with field surveys and velocity estimations along selected sections of the landslide.Finally, potential areas prone to failure or reactivation were identified, and a new simulation was performed that considered the back-calculated rheological parameters.
ConclusionsRapid landslides are one of the most dangerous natural hazards and are one of the most frequent natural disasters in the world. Therefore, prediction of post-failure motion is an essential component of hazard assessment when a potential source of a mobile landslide it is located.To assess the risk affecting the area, both numerical and empirical methods have been proposed, in order to predict the runout phase of the phenomenon.For the numerical modelling of the landslide, carried out with DAN-3D code, the best results were obtained by using a Voellmy reological model, with a constant turbulence parameter (ξ) of 250 m/s2 and a friction parameter (μ) comprised between 0.15 and 0.19.The rheological parameters obtained through dynamic back analyses were used to evaluate the propagation phase and the deposition areas of new potential landslides, that could affect the same area of the 25th March 2015 event.The predicted runout length obtained by the DAN3D software was compared to runout lengths predicted by the Corominas (Can Geotech J 33:260–271, 1996), (Nat. Hazards 19, 47-77) and (UNICIV Report, R-416, School of Civil & Environmental Engineering, UNSW, Sydney Australia 2003) empirical relations.All the data confirm that the impact area of possible future events will be smaller than the 2015 event, probably due to the safety measures established after the landslide.
[en] This paper is the result of a joint work between geophysicists and archaeologists in which the authors have used geophysical techniques to investigate the Greek and Roman settlement of Paestum, southern Italy for preventive archaeological research (commonly termed 'rescue archaeology') on an area of the ancient settlement affected by new building work and infrastructure. Starting from a background analysis of the archaeological and geological features of the site, an integrated geophysical approach based on magnetic, GPR and geoelectrical surveys was carried out on the Santa Venera area, a site selected to build a car parking. High-density and high-resolution cross-correlated geophysical surveys were carried out in different parts of the area to better resolve the structures. Systematic excavations confirmed the clues suggested by geophysical prospecting about the presence of archaeological remains such as walls, canals and tombs. By the use of non-destructive geophysical techniques a two-fold aim was reached: to properly plan the building of the infrastructure and preserve the ancient artefacts according to the advanced European guidelines on the protection of archaeological heritage
[en] Described is the model of the prospecting object used in the methodic for data processing of prospecting radiometric studies. It is based on the determination of distribution density of points or areas with anomalous values of measured parameters per area unit. Anomalies of extensity show the areas of ore manifestations of statistically ordered development. Numerical characteristics and morphology of knots of extensity fields identified depend on the scale of mineralization and geologostructural conditions. The appearance of contrast anomalies resulting from ore processes is correlatively connected with the density of slight anomalies manifestation. The use of the extension parameter permits to correlate anomalous fields identified with geological structures and to separate local areas of anomalous fields for evaluation activities
[en] Budget estimate for seismic projects, whether related to the application for an open exploration permit, to the exploration phase of a permit already awarded or to the appraisal of a discovery or the development of a proven field, are generally requested from geophysicists well ahead of the opening of seismic bids which will reveal the actual costs of the project without ambiguity. With the growing application of 3D seismic and its integration with the reservoir development disciplines, the relative weight of seismic expenditures within the total cost of a project has now become a significant item which may affect its overall economic balance. Providing reliable and accurate seismic cost estimates and tailoring survey parameters to meet simultaneously technical objectives and budgetary limits have become essential elements of the geophysicists' role
[en] Systematic research for the deciphering of the physic and structure of Earth's crust in our country by geophysical methods were performed in the frame of Romanian Geological Institute since 1925. We put into evidence the principle achievements obtained by the geological and geophysical research for the mineral resources existing in the Romanian earth's crust. (authors)
[en] The purpose of the Los Alamos National Laboratory (LANL) Seismic Screening Method is to provide a comprehensive, rational, and inexpensive method for evaluating the relative seismic integrity of a large building inventory using substantial life-safety as the minimum goal. The substantial life-safety goal is deemed to be satisfied if the extent of structural damage or nonstructural component damage does not pose a significant risk to human life. The screening is limited to Performance Category (PC) -0, -1, and -2 buildings and structures. Because of their higher performance objectives, PC-3 and PC-4 buildings automatically fail the LANL Seismic Screening Method and will be subject to a more detailed seismic analysis. The Laboratory has also designated that PC-0, PC-1, and PC-2 unreinforced masonry bearing wall and masonry infill shear wall buildings fail the LANL Seismic Screening Method because of their historically poor seismic performance or complex behavior. These building types are also recommended for a more detailed seismic analysis. The results of the LANL Seismic Screening Method are expressed in terms of separate scores for potential configuration or physical hazards (Phase One) and calculated capacity/demand ratios (Phase Two). This two-phase method allows the user to quickly identify buildings that have adequate seismic characteristics and structural capacity and screen them out from further evaluation. The resulting scores also provide a ranking of those buildings found to be inadequate. Thus, buildings not passing the screening can be rationally prioritized for further evaluation. For the purpose of complying with Executive Order 12941, the buildings failing the LANL Seismic Screening Method are deemed to have seismic deficiencies, and cost estimates for mitigation must be prepared. Mitigation techniques and cost-estimate guidelines are not included in the LANL Seismic Screening Method
[en] The project of designing a radioactive total counts data collecting and processing system by using a pocket computer SHARP PC-15000(A) is discussed in the paper. The composition of the system, the features, the principles of the hardware and the software, and the applications of the system are also discussed