The globalization of geospatial data and geodetic reference frames is important for the overall development of both national and global economies. In accordance with the needs for defining a general ...geodetic reference frame, the United Nations General Assembly adopted the resolution "Global Geodetic Reference Frame for Sustainable Development (GGRF)" in 2015. The European Union member states have addressed the issue by adopting joint directives, recommendations and other acts to adapt national laws. Bosnia and Herzegovina and its neighboring countries, non-EU member states, have enacted appropriate legislation and decisions to adapt to the globalization of spatial data and reference frames. Therefore, the Federal Administration for Geodetic and Property Affairs (FGU) has undertaken certain activities in order to establish a new geodetic reference frame through changes in legislation, renewal and establishment of new reference systems and measurements. The paper will discuss the existing geodetic reference frame and the activities of the FGU on the introduction of new geodetic datums and map projections in the Federation of Bosnia and Herzegovina (FBiH).
Recent acceleration of sand extraction for anthropic use threatens the sustainability of this major resource. However, continental erosion and river transport, which produce sand and sediment in ...general, lack quantification at the global scale. Here, we develop a new geodetic method to infer the sediment discharge to ocean of the world's largest rivers. It combines the spatial distribution of modern sedimentation zones with new high-resolution (~170 km) data from the Gravity Recovery and Climate Experiment (GRACE) mission launched in 2002. We obtain sediment discharges consistent with in situ measurements for the Amazon, Ganges-Brahmaputra, Changjiang, Indus, and Magdalena rivers. This new approach enables to quantitatively monitor the contemporary erosion of continental basins drained by rivers with large sediment discharges and paves the way toward a better understanding of how natural and anthropic changes influence landscape dynamics.
The article describes the procedure for transformation between old and new horizontal geodetic datum in Bosnia and Herzegovina. Two triangle-based methods were used for transformation, which are ...based on irregular and regular triangular network. For development of transformation models two set of points were used, one for developing models (around 1200 points), and other for testing (around 850 points). Prior to development, all points were tested at presence of outliers, and outliers are marked in the points database. Results shows that large part of distortions in old triangulation network can be modeled with used methods. Maximal positional standard deviations with best model are 4.5 and 6.4 cm for two sets of points, respectively, while maximal positional discripencies are 30 and 40 cm for two sets of points. Each method has some advantages and disadvantages which are shown in this article. It is shown that the number, spatial distribution and quality of input data are crucial for development of highly accurate transformation model. Also, as an important contribution of this work, some problematic areas with irregular distortions are identified. Finally, some recommendations are given for improvement of developed models.
Forum papers are thought-provoking opinion pieces or essays founded in fact, sometimes containing speculation, on a civil engineering topic of general interest and relevance to the readership of the ...journal. The views expressed in this Forum article do not necessarily reflect the views of ASCE or the Editorial Board of the journal.
This study evaluates the applicability of different models of coordinate transformation between local and global geodetic datums. The results indicate the grid-based method as the best solution, ...assuming a sufficient density of tie points. Transformation based on a limited number of tie points, which do not reflect the real state of the survey basis in a particular area, have limited possibilities to reduce nonuniform and unequally distributed distortions that are usually found in the spatial data. This inevitably leads to the degradation of accuracy of transformation results, which is unacceptable. By using the optimal resolution grid model, which includes geodetic points from the area of the cadastral municipality that is being transformed, much better results are achieved compared to the model of distortion shifts used in the Federation of Bosnia and Herzegovina.
In order to monitor the landslide, a geodetic network was established in the area of the Urbas landslide, on the basis of which the movements of control points can be calculated. After various ...analyses, only two small areas near the Urbas landslide proved to be stable, so we established four reference points there. In this research we defined the geodetic datum of the geodetic network of the Urbas landslide. KEY WORDS geodetic network, Urbas landslide, sets of angles, adjustment of geodetic network, geodetic datum, stability of reference points (ProQuest: ... denotes formulae omitted.) 1 UVOD Preučevano območje je del Potoške planine, ki geografsko spada v Zahodne Karavanke, natančneje na pobočje Belščice, ki se razteza med Viševnikom nad Medjim dolom in Potoškim Stolom in je mejno območje med Slovenijo in Avstrijo (Peternel, 2017).
In this study, we have conducted an investigation on the impact of the coordinates' transformation on local variations of geometric geoid. The study area is limited by 1°43′12″ to 4°00′37″ East and ...13°01′57″ to 14°31′20″ North in the southwest of the Niger Republic. We used 39 network GPS/levelling points established by the Japan International Cooperation Agency (JICA) and the National Geographic Institute of Niger (IGNN), including the DOPPLER point ANG302/no.65. Using other coordinates of point no. 65 provided by IGNN, we transformed the points into WGS84 and computed a new geometric geoid model. The comparison of the new model with EGM2008 geoid up to d/o 2160 gives the STD of 15 cm and the RMS of 16cm. Local variations of the geometric geoids, were compared to that of EGM2008 geoid. The comparison through basic statistics, trend lines and 3D overlaps, showed a similar trend between the geometric geoid from the transformed coordinates and that of EGM2008. On the contrary, the JICA-IGNN geometric geoid generated an opposite and exaggerated trend. The Jarque-Bera test confirms that the three samples follow a normal distribution at the significance level α = 5%. The equality of variances between EGM2008 and JICA-IGNN geoids has been rejected by the Fisher's F-Test/two-tailed at α = 10%. However the test confirms the variances equality between EGM2008 and the transformed geometric geoid at α = 5% and α = 10%. The two-tailed Student's T-Test at α = 5% also confirms the equality of means between EGM2008 geoid and transformed geometric geoid samples.
Transformation between ellipsoids also called datum transformation implies coordinate conversion from one ellipsoid to another ellipsoid, most frequently to be done by Helmert seven-parameter ...transformation. Transformation parameters involve three rotation, three translation and scale factor and they can be calculated using reference points which are known before and after transformation. Transformation parameters can be obtained with appropriate measurements and in accoradance with measurement uncertainties, they are produce errors of transformed coordinates. This paper describes standard errors of transformed coordinates using Helmert seven-parameter transformation, when switching from ellipsoid WGS84 to Bessel ellipsoid.
Earthquake and Volcano Deformationis the first textbook to present the mechanical models of earthquake and volcanic processes, emphasizing earth-surface deformations that can be compared with ...observations from Global Positioning System (GPS) receivers, Interferometric Radar (InSAR), and borehole strain- and tiltmeters. Paul Segall provides the physical and mathematical fundamentals for the models used to interpret deformation measurements near active faults and volcanic centers.
Segall highlights analytical methods of continuum mechanics applied to problems of active crustal deformation. Topics include elastic dislocation theory in homogeneous and layered half-spaces, crack models of faults and planar intrusions, elastic fields due to pressurized spherical and ellipsoidal magma chambers, time-dependent deformation resulting from faulting in an elastic layer overlying a viscoelastic half-space and related earthquake cycle models, poroelastic effects due to faulting and magma chamber inflation in a fluid-saturated crust, and the effects of gravity on deformation. He also explains changes in the gravitational field due to faulting and magmatic intrusion, effects of irregular surface topography and earth curvature, and modern concepts in rate- and state-dependent fault friction. This textbook presents sample calculations and compares model predictions against field data from seismic and volcanic settings from around the world.
Earthquake and Volcano Deformationrequires working knowledge of stress and strain, and advanced calculus. It is appropriate for advanced undergraduates and graduate students in geophysics, geology, and engineering.
Professors: A supplementary Instructor's Manual is available for this book. It is restricted to teachers using the text in courses. For information on how to obtain a copy, refer to: http://press.princeton.edu/class_use/solutions.html
Although a dynamic or semi-dynamic datum has been adopted in some countries, it remains a challenge if a long-term stable datum is to be established in a tectonic active area. This study presents an ...approach to realistically reflect the time dependent behaviors of ground reference points while maintaining the long-term stability of a datum. An adaptive approach coupled with the Euler motion model is proposed for dividing an area into blocks. A least-squares collocation is then applied for modeling the residual velocities in each block. A case study using the data from 375 continuously operated GNSS stations in Taiwan is presented. It is illustrated that the complex surface kinematics in this region can be divided into three blocks. Significant reductions up to 64% of residual velocities were obtained. This shows that a stable datum can be established in a region with active and complicated surface kinematics by implementing the proposed.
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