35 research outputs found

    Site and Basin Effects on Seismic Hazard in Indonesia:Sulawesi and Jakarta Case Studies

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    Earthquakes are among the most costly, devastating and deadly natural hazards. The extent of the seismic hazard is often influenced by factors like the source location and site characteristics, while the susceptibility of assets is influenced by the population density, building design, infrastructure and urban planning. A comprehensive knowledge of the nature of source and local geology enables the establishment of an effective urban planning that takes into account the potential seismic hazard, which in turn may reduce the degree of vulnerability. The first probabilistic seismic hazard assessment (PSHA) incorporating the effects of local site characteristic for the island of Sulawesi in Indonesia has been conducted. Most of the island, with the exception of South Sulawesi, is undergoing rapid deformation. This leads to high hazard in most regions (such that PGA > 0.4g at 500 year return period including site effects) and extremely high hazard (like PGA > 0.8 g at 500 year return period) along fast-slipping crustal fault. On the other hand, a distant site relative to fault might suffer higher ground motion if that site is composed of soft soil. This research has proven that incorporating near-surface physical properties, in this case is represented by VS30, surface geology contribute significantly to ground motions, consequently, responsible for potential building damage. The PSHA study that took place in Sulawesi took us move further, investigate the effect of deep structure on seismic waves. Jakarta was chosen for its location sitting on less known deep sediment basin and economic and political importances. A dense portable-seismic-broadband network, comprising 96 stations, has been operated within four months covering the Jakarta. The seismic network sampled broadband seismic-noise mostly originating from ocean waves and anthropogenic activity. We used Horizontal-toVertical Spectral Ratio (HVSR) measurements of the ambient seismic noise to estimate the fundamental-mode Rayleigh wave ellipticity curves, which were used to infer the seismic velocity structure of the Jakarta Basin. By mapping and modeling the spatial variation of low-frequency (0.124{0.249 Hz) HVSR peaks, this study reveals variations in the depth to the Miocene basement. To map these velocity profiles of unknown complexity, we employ a Transdimensional-Bayesian framework for the inversion of HVSR curves for 1D profiles of velocity and density beneath each station. The inverted velocity profiles show a sudden change of basement depth from 400 to 1350 m along N-S profile through the center of the city, with an otherwise gentle increase in basin depth from south to north. Seismic wave modelings are conducted afterward and shows that for very deep basin of Jakarta, available ground motion prediction equation (GMPE) is less sufficient in capturing the effect of basin geometry on seismic waves. Earrthquake scenario modeling using SPECFEM2D is performed to comprehend the effect of deep basin on ground motions. This modeling reveals that the city may experience high peak ground velocity (PGV) during large megathrust earthquake. The complexity of the basin is responsible for magnifying ground motions observed in the basin

    The NASA Geodynamics Program: An overview

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    This NASA Geodynamics Program overview collectively examines the history, scientific basis, status, and results of the NASA Program and outlines plans for the next five to eight years. It is intended as an informative nontechnical discussion of geodynamics research

    Submarine mass wasting processes along the continental slope of the Middle American Trench

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    This Thesis work presents a regional-scale study of submarine mass-wasting phenomena of the continental slope of a subduction zone. The nature of the study makes it a new, outstanding contribution for two main reasons: 1) The large-scale and interdisciplinary characters of the study conform a comprehensive investigation - unmatched by any other previous study- of land sliding processes along the slope of a tectonically-active convergent margin. 2) The investigation is also unique because it looks into the processes at a subduction zone dominated by tectonic erosion. This type of geological setting represents about 50% of the world subduction zone systems, but it has been overlooked in previous studies of mass wasting processes. The study region is located along a segment of the Middle America Trench (MAT) that extends about 1500 km from the Costa Rica - Panama border to the Guatemala - Mexico boundary. The study investigates the structures of the continental slope of the Pacific-Ocean-side of Central America and the trench-region of the incoming oceanic Cocos plate. We have investigated the distribution of submarine slope failures and their deposits, the type of failures, and their seafloor morphology. We have also investigated possible preconditioning and triggering mechanisms, and the relationship of those mechanisms and the variability in failure type to the tectonic processes of this particular geological setting. Finally, we have made some inferences of the significance of mass wasting processes in the long-term evolution of the slope, compared to other geological settings. The Central America subduction zone has been the locus of intense, continued geoscientific investigation since the late 1970s that culminated with the selection of the region as the focus site for the US-Margins program and the German SFB574 during the first decade of the 21st century. Those two programs included research in a broad range of topics that attempted to advance our understanding of the entire subduction zone system. As a result numerous projects from both communities have benefited from close collaborations. This PhD work is integrated within the research project SFB 574, financed by the DFG, that has as main research goal investigations on “Volatiles and fluids in subduction zones and their impact on climate feedback and trigger mechanisms for natural disasters”. We have analyzed a database containing a compilation of multibeam bathymetry of 7 research cruises, 3 cruises of side-scan sonar imagery and core samples of a dedicated cruise. The database has been assembled in a collaborative effort between both USMargins and SFB 574 communities. Based on seafloor morphology and backscatter imagery, and seismic images we have mapped and classified 147 submarine slope failures in the region. Slope failures vary in their type, abundance and distribution along and across the slope to define six distinct segments along the MAT. The lateral extent of the six segments correlates well with similar along-trench segmentation in the character of the incoming ocean plate, expressed as changes in its relief, age and crustal thickness. We have also found that the six along-margin segments display changes in the across-slope structuring of the different geological elements, including changes in the morphological expression of upper, middle and lower slope, total slope width, and slope dip angle. This structuring of the elements of the slope appears to be related to a longterm evolution caused by the tectonic processes associated to subduction erosion. One segment covers the area of under-thrusting of Cocos Ridge under the shelf-slope offshore Osa Peninsula (southern Costa Rica). Here, 1-km-high narrow, sharp ridges and small conical seamounts festooning Cocos Ridge cause slumps often with rock and debris avalanches from a short, steep continental slope. A second segment occurs offshore central Costa Rica, where large conical seamounts and ridges of 1-3 km high and 40 km wide under-thrust the continental slope causing large re-entries of the slope toe, and furrows across the slope formed by collapse, of previously uplifted upper plate, along steep headwalls behind the under-thrusting seamounts. Failures have generated large slumps, debris flows and rock avalanches containing blocks up to 500 m in diameter. In contrast at a third segment in northern Costa Rica, offshore the North Nicoya Peninsula, a smooth incoming plate is parallel opposite by a continental slope lacking relevant mass wasting structures. The contiguous fourth segment offshore Nicaragua displays a steep middle slope with large translational slides opposite an ocean plate with numerous 1-km-tall seamounts and 100s-meter-high horst and graben relief. Under the fifth segment, offshore El Salvador, subducts a well developed horst and graben relief, but somewhat surprising the segment displays a generally failure-free slope, and only the uppermost slope displays a series of small translation slides The plate under-thrusting the sixth segment offshore Guatemala is similarly characterized by a horst and graben terrain. However, here a steeper slope exhibits frequent, small-scale failures, a few km wide, across the entire segment

    Semantic location extraction from crowdsourced data

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    Crowdsourced Data (CSD) has recently received increased attention in many application areas including disaster management. Convenience of production and use, data currency and abundancy are some of the key reasons for attracting this high interest. Conversely, quality issues like incompleteness, credibility and relevancy prevent the direct use of such data in important applications like disaster management. Moreover, location information availability of CSD is problematic as it remains very low in many crowd sourced platforms such as Twitter. Also, this recorded location is mostly related to the mobile device or user location and often does not represent the event location. In CSD, event location is discussed descriptively in the comments in addition to the recorded location (which is generated by means of mobile device's GPS or mobile communication network). This study attempts to semantically extract the CSD location information with the help of an ontological Gazetteer and other available resources. 2011 Queensland flood tweets and Ushahidi Crowd Map data were semantically analysed to extract the location information with the support of Queensland Gazetteer which is converted to an ontological gazetteer and a global gazetteer. Some preliminary results show that the use of ontologies and semantics can improve the accuracy of place name identification of CSD and the process of location information extraction

    Contemporary Robotics

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    This book book is a collection of 18 chapters written by internationally recognized experts and well-known professionals of the field. Chapters contribute to diverse facets of contemporary robotics and autonomous systems. The volume is organized in four thematic parts according to the main subjects, regarding the recent advances in the contemporary robotics. The first thematic topics of the book are devoted to the theoretical issues. This includes development of algorithms for automatic trajectory generation using redudancy resolution scheme, intelligent algorithms for robotic grasping, modelling approach for reactive mode handling of flexible manufacturing and design of an advanced controller for robot manipulators. The second part of the book deals with different aspects of robot calibration and sensing. This includes a geometric and treshold calibration of a multiple robotic line-vision system, robot-based inline 2D/3D quality monitoring using picture-giving and laser triangulation, and a study on prospective polymer composite materials for flexible tactile sensors. The third part addresses issues of mobile robots and multi-agent systems, including SLAM of mobile robots based on fusion of odometry and visual data, configuration of a localization system by a team of mobile robots, development of generic real-time motion controller for differential mobile robots, control of fuel cells of mobile robots, modelling of omni-directional wheeled-based robots, building of hunter- hybrid tracking environment, as well as design of a cooperative control in distributed population-based multi-agent approach. The fourth part presents recent approaches and results in humanoid and bioinspirative robotics. It deals with design of adaptive control of anthropomorphic biped gait, building of dynamic-based simulation for humanoid robot walking, building controller for perceptual motor control dynamics of humans and biomimetic approach to control mechatronic structure using smart materials

    Advanced Location-Based Technologies and Services

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    Since the publication of the first edition in 2004, advances in mobile devices, positioning sensors, WiFi fingerprinting, and wireless communications, among others, have paved the way for developing new and advanced location-based services (LBSs). This second edition provides up-to-date information on LBSs, including WiFi fingerprinting, mobile computing, geospatial clouds, geospatial data mining, location privacy, and location-based social networking. It also includes new chapters on application areas such as LBSs for public health, indoor navigation, and advertising. In addition, the chapter on remote sensing has been revised to address advancements

    Literature review of the remote sensing of natural resources

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    A bibliography is presented concerning remote sensing techniques. Abstracts of recent periodicals are included along with author, and keyword indexes

    Earth resources, a continuing bibliography with indexes

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    This bibliography lists 541 reports, articles and other documents introduced into the NASA scientific and technical information system. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economic analysis

    The relationship between active faulting and fluvial geomorphology: a case study in the Gediz Graben, Turkey.

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    Identifying tectonically active faults and quantifying rates of movement is a key challenge in the Earth Sciences, in addition to this the interactions between active faulting and the landscape, specifically involving the fluvial network, is a relatively new area of study. Previous work has highlighted the value of understanding how the fluvial network responds to active tectonics, showing that a comprehensive understanding of the dynamic relationship between fluvial geomorphology and active tectonics is an important next step in geological research. This study presents new information about the poorly constrained Quaternary tectonic history of the Gediz Graben, Turkey, providing the first quantification of rates of movement of the key fault array that presently controlling graben topography. The fluvial network has been investigated and the data has been used in order to add resolution to the tectonic history for the fault array, allowing for the quantification of post-linkage throw rates. The study then investigates the key controls on the behaviour of the fluvial network that cross the active topography building fault array in the Gediz Graben. This study shows that there has been a linkage event occurring between 0.6 – 1 Ma, involving the three segments of the graben bounding fault array. The pre- and post-linkage throw rates are then extrapolated using data derived from the fluvial network, showing a faulting enhancement factor of 3 at the centre of the fault array, with the throw rate at the centre of the array predicted to have increased from a pre-linkage rate of 0.6 ± 0.1 mm/yr to a rate of 2 ± 0.2 mm/yr. This research provides evidence that the fluvial network can be used in conjunction with other types of evidence to provide a greater resolution tectonic history. Using both digital data and field studies this research presents an examination of the factors that influence the behaviour of bedrock rivers undergoing perturbation due to tectonics. Factors such as drainage area, tectonic throw rates and lithology have been investigated and the complicated interactions of these variables with the fluvial system have been quantified. This study shows that the bedrock rivers are a significant source of information about tectonics, but further work is needed to resolve quantitatively how various factors influence how rivers adjust to tectonic perturbation, in a variety of tectonic situations, in order to enable river to be used as a primary tool for deriving information about tectonics

    Advances and Applications of Dezert-Smarandache Theory (DSmT) for Information Fusion (Collected Works), Vol. 4

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    The fourth volume on Advances and Applications of Dezert-Smarandache Theory (DSmT) for information fusion collects theoretical and applied contributions of researchers working in different fields of applications and in mathematics. The contributions (see List of Articles published in this book, at the end of the volume) have been published or presented after disseminating the third volume (2009, http://fs.unm.edu/DSmT-book3.pdf) in international conferences, seminars, workshops and journals. First Part of this book presents the theoretical advancement of DSmT, dealing with Belief functions, conditioning and deconditioning, Analytic Hierarchy Process, Decision Making, Multi-Criteria, evidence theory, combination rule, evidence distance, conflicting belief, sources of evidences with different importance and reliabilities, importance of sources, pignistic probability transformation, Qualitative reasoning under uncertainty, Imprecise belief structures, 2-Tuple linguistic label, Electre Tri Method, hierarchical proportional redistribution, basic belief assignment, subjective probability measure, Smarandache codification, neutrosophic logic, Evidence theory, outranking methods, Dempster-Shafer Theory, Bayes fusion rule, frequentist probability, mean square error, controlling factor, optimal assignment solution, data association, Transferable Belief Model, and others. More applications of DSmT have emerged in the past years since the apparition of the third book of DSmT 2009. Subsequently, the second part of this volume is about applications of DSmT in correlation with Electronic Support Measures, belief function, sensor networks, Ground Moving Target and Multiple target tracking, Vehicle-Born Improvised Explosive Device, Belief Interacting Multiple Model filter, seismic and acoustic sensor, Support Vector Machines, Alarm classification, ability of human visual system, Uncertainty Representation and Reasoning Evaluation Framework, Threat Assessment, Handwritten Signature Verification, Automatic Aircraft Recognition, Dynamic Data-Driven Application System, adjustment of secure communication trust analysis, and so on. Finally, the third part presents a List of References related with DSmT published or presented along the years since its inception in 2004, chronologically ordered
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