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Sample records for 3d seismic imaging

  1. 3D seismic image processing for interpretation

    NASA Astrophysics Data System (ADS)

    Wu, Xinming

    Extracting fault, unconformity, and horizon surfaces from a seismic image is useful for interpretation of geologic structures and stratigraphic features. Although interpretation of these surfaces has been automated to some extent by others, significant manual effort is still required for extracting each type of these geologic surfaces. I propose methods to automatically extract all the fault, unconformity, and horizon surfaces from a 3D seismic image. To a large degree, these methods just involve image processing or array processing which is achieved by efficiently solving partial differential equations. For fault interpretation, I propose a linked data structure, which is simpler than triangle or quad meshes, to represent a fault surface. In this simple data structure, each sample of a fault corresponds to exactly one image sample. Using this linked data structure, I extract complete and intersecting fault surfaces without holes from 3D seismic images. I use the same structure in subsequent processing to estimate fault slip vectors. I further propose two methods, using precomputed fault surfaces and slips, to undo faulting in seismic images by simultaneously moving fault blocks and faults themselves. For unconformity interpretation, I first propose a new method to compute a unconformity likelihood image that highlights both the termination areas and the corresponding parallel unconformities and correlative conformities. I then extract unconformity surfaces from the likelihood image and use these surfaces as constraints to more accurately estimate seismic normal vectors that are discontinuous near the unconformities. Finally, I use the estimated normal vectors and use the unconformities as constraints to compute a flattened image, in which seismic reflectors are all flat and vertical gaps correspond to the unconformities. Horizon extraction is straightforward after computing a map of image flattening; we can first extract horizontal slices in the flattened space

  2. Walker Ranch 3D seismic images

    DOE Data Explorer

    Robert J. Mellors

    2016-03-01

    Amplitude images (both vertical and depth slices) extracted from 3D seismic reflection survey over area of Walker Ranch area (adjacent to Raft River). Crossline spacing of 660 feet and inline of 165 feet using a Vibroseis source. Processing included depth migration. Micro-earthquake hypocenters on images. Stratigraphic information and nearby well tracks added to images. Images are embedded in a Microsoft Word document with additional information. Exact location and depth restricted for proprietary reasons. Data collection and processing funded by Agua Caliente. Original data remains property of Agua Caliente.

  3. 3-D seismic imaging of complex geologies

    SciTech Connect

    Womble, D.E.; Dosanjh, S.S.; VanDyke, J.P.; Oldfield, R.A.; Greenberg, D.S.

    1995-02-01

    We present three codes for the Intel Paragon that address the problem of three-dimensional seismic imaging of complex geologies. The first code models acoustic wave propagation and can be used to generate data sets to calibrate and validate seismic imaging codes. This code reported the fastest timings for acoustic wave propagation codes at a recent SEG (Society of Exploration Geophysicists) meeting. The second code implements a Kirchhoff method for pre-stack depth migration. Development of this code is almost complete, and preliminary results are presented. The third code implements a wave equation approach to seismic migration and is a Paragon implementation of a code from the ARCO Seismic Benchmark Suite.

  4. Imaging fault zones using 3D seismic image processing techniques

    NASA Astrophysics Data System (ADS)

    Iacopini, David; Butler, Rob; Purves, Steve

    2013-04-01

    Significant advances in structural analysis of deep water structure, salt tectonic and extensional rift basin come from the descriptions of fault system geometries imaged in 3D seismic data. However, even where seismic data are excellent, in most cases the trajectory of thrust faults is highly conjectural and still significant uncertainty exists as to the patterns of deformation that develop between the main faults segments, and even of the fault architectures themselves. Moreover structural interpretations that conventionally define faults by breaks and apparent offsets of seismic reflectors are commonly conditioned by a narrow range of theoretical models of fault behavior. For example, almost all interpretations of thrust geometries on seismic data rely on theoretical "end-member" behaviors where concepts as strain localization or multilayer mechanics are simply avoided. Yet analogue outcrop studies confirm that such descriptions are commonly unsatisfactory and incomplete. In order to fill these gaps and improve the 3D visualization of deformation in the subsurface, seismic attribute methods are developed here in conjunction with conventional mapping of reflector amplitudes (Marfurt & Chopra, 2007)). These signal processing techniques recently developed and applied especially by the oil industry use variations in the amplitude and phase of the seismic wavelet. These seismic attributes improve the signal interpretation and are calculated and applied to the entire 3D seismic dataset. In this contribution we will show 3D seismic examples of fault structures from gravity-driven deep-water thrust structures and extensional basin systems to indicate how 3D seismic image processing methods can not only build better the geometrical interpretations of the faults but also begin to map both strain and damage through amplitude/phase properties of the seismic signal. This is done by quantifying and delineating the short-range anomalies on the intensity of reflector amplitudes

  5. Imaging thin-bed reservoirs with 3-D seismic

    SciTech Connect

    Hardage, B.A.

    1996-12-01

    This article explains how a 3-D seismic data volume, a vertical seismic profile (VSP), electric well logs and reservoir pressure data can be used to image closely stacked thin-bed reservoirs. This interpretation focuses on the Oligocene Frio reservoir in South Texas which has multiple thin-beds spanning a vertical interval of about 3,000 ft.

  6. 3D seismic imaging on massively parallel computers

    SciTech Connect

    Womble, D.E.; Ober, C.C.; Oldfield, R.

    1997-02-01

    The ability to image complex geologies such as salt domes in the Gulf of Mexico and thrusts in mountainous regions is a key to reducing the risk and cost associated with oil and gas exploration. Imaging these structures, however, is computationally expensive. Datasets can be terabytes in size, and the processing time required for the multiple iterations needed to produce a velocity model can take months, even with the massively parallel computers available today. Some algorithms, such as 3D, finite-difference, prestack, depth migration remain beyond the capacity of production seismic processing. Massively parallel processors (MPPs) and algorithms research are the tools that will enable this project to provide new seismic processing capabilities to the oil and gas industry. The goals of this work are to (1) develop finite-difference algorithms for 3D, prestack, depth migration; (2) develop efficient computational approaches for seismic imaging and for processing terabyte datasets on massively parallel computers; and (3) develop a modular, portable, seismic imaging code.

  7. 3D Seismic Imaging over a Potential Collapse Structure

    NASA Astrophysics Data System (ADS)

    Gritto, Roland; O'Connell, Daniel; Elobaid Elnaiem, Ali; Mohamed, Fathelrahman; Sadooni, Fadhil

    2016-04-01

    The Middle-East has seen a recent boom in construction including the planning and development of complete new sub-sections of metropolitan areas. Before planning and construction can commence, however, the development areas need to be investigated to determine their suitability for the planned project. Subsurface parameters such as the type of material (soil/rock), thickness of top soil or rock layers, depth and elastic parameters of basement, for example, comprise important information needed before a decision concerning the suitability of the site for construction can be made. A similar problem arises in environmental impact studies, when subsurface parameters are needed to assess the geological heterogeneity of the subsurface. Environmental impact studies are typically required for each construction project, particularly for the scale of the aforementioned building boom in the Middle East. The current study was conducted in Qatar at the location of a future highway interchange to evaluate a suite of 3D seismic techniques in their effectiveness to interrogate the subsurface for the presence of karst-like collapse structures. The survey comprised an area of approximately 10,000 m2 and consisted of 550 source- and 192 receiver locations. The seismic source was an accelerated weight drop while the geophones consisted of 3-component 10 Hz velocity sensors. At present, we analyzed over 100,000 P-wave phase arrivals and performed high-resolution 3-D tomographic imaging of the shallow subsurface. Furthermore, dispersion analysis of recorded surface waves will be performed to obtain S-wave velocity profiles of the subsurface. Both results, in conjunction with density estimates, will be utilized to determine the elastic moduli of the subsurface rock layers.

  8. Automatic detection of karstic sinkholes in seismic 3D images using circular Hough transform

    NASA Astrophysics Data System (ADS)

    Heydari Parchkoohi, Mostafa; Keshavarz Farajkhah, Nasser; Salimi Delshad, Meysam

    2015-10-01

    More than 30% of hydrocarbon reservoirs are reported in carbonates that mostly include evidence of fractures and karstification. Generally, the detection of karstic sinkholes prognosticate good quality hydrocarbon reservoirs where looser sediments fill the holes penetrating hard limestone and the overburden pressure on infill sediments is mostly tolerated by their sturdier surrounding structure. They are also useful for the detection of erosional surfaces in seismic stratigraphic studies and imply possible relative sea level fall at the time of establishment. Karstic sinkholes are identified straightforwardly by using seismic geometric attributes (e.g. coherency, curvature) in which lateral variations are much more emphasized with respect to the original 3D seismic image. Then, seismic interpreters rely on their visual skills and experience in detecting roughly round objects in seismic attribute maps. In this paper, we introduce an image processing workflow to enhance selective edges in seismic attribute volumes stemming from karstic sinkholes and finally locate them in a high quality 3D seismic image by using circular Hough transform. Afterwards, we present a case study from an on-shore oilfield in southwest Iran, in which the proposed algorithm is applied and karstic sinkholes are traced.

  9. 3D and 4D Seismic Imaging in the Oilfield; the state of the art

    NASA Astrophysics Data System (ADS)

    Strudley, A.

    2005-05-01

    Seismic imaging in the oilfield context has seen enormous changes over the last 20 years driven by a combination of improved subsurface illumination (2D to 3D), increased computational power and improved physical understanding. Today Kirchhoff Pre-stack migration (in time or depth) is the norm with anisotropic parameterisation and finite difference methods being increasingly employed. In the production context Time-Lapse (4D) Seismic is of growing importance as a tool for monitoring reservoir changes to facilitate increased productivity and recovery. In this paper we present an overview of state of the art technology in 3D and 4D seismic and look at future trends. Pre-stack Kirchhoff migration in time or depth is the imaging tool of choice for the majority of contemporary 3D datasets. Recent developments in 3D pre-stack imaging have been focussed around finite difference solutions to the acoustic wave equation, the so-called Wave Equation Migration methods (WEM). Application of finite difference solutions to imaging is certainly not new, however 3D pre-stack migration using these schemes is a relatively recent development driven by the need for imaging complex geologic structures such as sub salt, and facilitated by increased computational resources. Finally there are a class of imaging methods referred to as beam migration. These methods may be based on either the wave equation or rays, but all operate on a localised (in space and direction) part of the wavefield. These methods offer a bridge between the computational efficiency of Kirchhoff schemes and the improved image quality of WEM methods. Just as 3D seismic has had a radical impact on the quality of the static model of the reservoir, 4D seismic is having a dramatic impact on the dynamic model. Repeat shooting of seismic surveys after a period of production (typically one to several years) reveals changes in pressure and saturation through changes in the seismic response. The growth in interest in 4D seismic

  10. Combining sequence stratigraphy with 3-D seismic imaging in low-accommodation basins

    SciTech Connect

    Hardage, B.A.; Carr, D.L.; Simmons, J.L. Jr.

    1995-12-31

    Pennsylvania-age rocks in several areas of the Midcontinent of the United States were deposited in low-accommodation basinal settings, that is, in basinal areas where only modest verticle reliefs could accept the sediment influx. Many thin Pennsylvanian sequences in these low-accommodation environments exhibit severe lateral heterogeneity because they have been extensively reworked by repeated transgressions and regressions of a fluctuating sea. Consequently, the distinctive geometries of relic depositional features (such as meandering channels) tend to be distorted or even totally destroyed, as compared with how such geometries appear in high-accommodation basins where depositional topography, once buried, is rarely exposed to destructive processes. Our objectives are to show examples of 3-D seismic images of several depositional topographies in a moderate- to low-accommodation basin and to explain how these thin sequences can be identified in well control and interpreted in 3-D seismic data volumes.

  11. Sequence stratigraphy and 3-D seismic imaging in low-accommodation basins

    SciTech Connect

    Hardage, B.A.; Carr, D.L.; Hamilton, D.S.; Simmons, J.L. Jr. )

    1996-01-01

    Pennsylvanian-age rocks in several areas of the Midcontinent of the United States were deposited in low-accommodation basinal settings. Many sequences in these low-accommodation environments exhibit severe lateral heterogeneity because they have been extensively reworked by repeated transgressions and regressions. Consequently, the distinctive geometries of relic depositional features tend to be distorted or totally destroyed, in contrast to such geometries in high-accommodation basins where depositional topography, once buried, is rarely exposed to erosional processes. Our objective is to show how these thin and obscure low-accommodation sequences can be identified in well control and interpreted in 3-D seismic data volumes. Numerous, deep-rooted karst-collapse zones affected the areal continuity of many sequences in some Midcontinent basins. We combine sequence stratigraphy with 3-D seismic imaging to document that many of these karst-collapse zones originate at deep Ellenburger ( ) levels and then extend vertically for a distance of 2,000 ft (600 m) or more into Pennsylvanian-age rocks. We also offer evidence that properly chosen seismic attributes, calculated in thin, accurately defined seismic time windows that correspond to log-defined sequences, show compartmented reservoir facies in low-accommodation basins.

  12. Sequence stratigraphy and 3-D seismic imaging in low-accommodation basins

    SciTech Connect

    Hardage, B.A.; Carr, D.L.; Hamilton, D.S.; Simmons, J.L. Jr.

    1996-12-31

    Pennsylvanian-age rocks in several areas of the Midcontinent of the United States were deposited in low-accommodation basinal settings. Many sequences in these low-accommodation environments exhibit severe lateral heterogeneity because they have been extensively reworked by repeated transgressions and regressions. Consequently, the distinctive geometries of relic depositional features tend to be distorted or totally destroyed, in contrast to such geometries in high-accommodation basins where depositional topography, once buried, is rarely exposed to erosional processes. Our objective is to show how these thin and obscure low-accommodation sequences can be identified in well control and interpreted in 3-D seismic data volumes. Numerous, deep-rooted karst-collapse zones affected the areal continuity of many sequences in some Midcontinent basins. We combine sequence stratigraphy with 3-D seismic imaging to document that many of these karst-collapse zones originate at deep Ellenburger (?) levels and then extend vertically for a distance of 2,000 ft (600 m) or more into Pennsylvanian-age rocks. We also offer evidence that properly chosen seismic attributes, calculated in thin, accurately defined seismic time windows that correspond to log-defined sequences, show compartmented reservoir facies in low-accommodation basins.

  13. High-Resolution 3D Seismic Imaging of Fluid Flow Anomalies in the Southwest Barents Sea

    NASA Astrophysics Data System (ADS)

    Planke, S.; Eriksen, F. N.; Eriksen, O. K.; Assad, M.; Stokke, H. H.

    2014-12-01

    Fluid flow features imaged as gas flares in the water column, pockmarks and mud volcanoes on the seabed, and high-amplitude cross-cutting reflections and bright spots in the sub-surface are abundant in the SW Barents Sea offshore northern Norway. This region is covered by extensive conventional 2D and 3D deep penetration seismic reflection data and multibeam bathymetry. High-resolution 3D P-Cable seismic data have been acquired in the SW Barents Sea over the past few years to image the uppermost ca. 500 m of the sub-surface. The P-Cable system consist of 12 to 16 short streamers (25 m) that are towed on a cross-cable perpendicular to the vessel's steaming direction. This configuration allows for acquisition of seismic data with high trace density, typically with 6 m in-line separation. The vertical resolution is a good as 1-2 m using conventional site survey air gun configurations. The sedimentary succession in the SW Barents Sea consists of upper Paleozoic evaporites overlaid by Mesozoic and Cenozoic clastic sediments. There are several organic-rich intervals in the sequence, including Paleozoic coals and Triassic and Jurassic marine source rocks that are locally in the oil or gas maturation windows. Glacial erosion has locally removed kilometer thick Cenozoic and Mesozoic successions, leaving the Mesozoic and Paleozoic strata in shallow sub-surface. The new high-resolution 3D surveys have targeted shallow fluid anomalies in the subsurface. These are imaged as high-amplitude reflections in fault blocks and structural highs, locally cross-cutting well-defined Mesozoic reflections. Commonly, disturbed reflections are present in overlying sequences, or high-amplitude reflections are imaged in the glacial overburden sediments. Locally, hundreds of pockmarks are imaged by the seafloor reflection. The deep cross-cutting reflections are interpreted as hydrocarbon accumulations that locally migrate towards the surface. The fluids are stored in shallow gas pockets or

  14. 3D reflection seismic imaging in the Kevitsa Ni-Cu-PGE deposits, northern Finland

    NASA Astrophysics Data System (ADS)

    Malehmir, A.; Juhlin, C.; Wijns, C.

    2012-04-01

    Better mining technology, coupled with the realization that outcropping or shallow deposits are becoming rarer has led the exploration industry to look ever deeper in the search for economic mineralization. Conventional geochemical and geophysical methods are less effective in these cases. The majority of geophysical methods that can penetrate to sufficient depth lack the necessary resolution to effectively complement drilling. Seismic surveys are one of the few methods that do have sufficient resolution at depth to constrain geological models of an ore deposit at the drilling scale. Although eventually drilling is required, reflection seismic methods can be used to partly reduce the drilling cost by focusing the drilling in key or strategically important areas. In this work, we present 3D reflection seismic data acquired in the Kevitsa Ni-Cu-PGE (platinum group elements) deposits, northern Finland. The 3D reflection seismic survey was conducted over an area of about 9 km2, where open-pit mining will start in mid-2012. The principal objective of the survey was to image major fault and fracture zones at depth that may have an impact on the mine stability and safety. Mine planning would then take into account the geometry of these zones at Kevitsa. Processing results show both gently dipping and steeply dipping reflections from depths of about 2 km to as shallow as 150-200 m. Many of the reflections are interpreted to originate from either fault systems or internal magmatic layering within the Kevitsa main intrusion. Further correlation between the surface seismic data and VSP data suggests that numerous faults are present in the imaged volume based upon time shifts or phase changes along horizontal to gently dipping reflections. Some of these faults cross the planned open-pit mine at depths of about 300-500 m, and are therefore critical for geotechnical planning. In terms of in-pit and near-mine exploration, the magmatic layering internal to the intrusion controls

  15. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2002-05-01

    Borehole seismology is the highest resolution geophysical imaging technique available to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This proposal takes direct aim at this shortcoming. P/GSI is developing a 400 level 3C clamped downhole seismic receiver array for borehole seismic 3D imaging. This array will remove the acquisition barrier to record the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. By using 3C surface seismic or borehole seismic sources the 400 level receiver array will furthermore facilitate 9C reservoir imaging. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the fluid types. The data quality and the data volumes from a 400 level 3C array will allow us to develop the data processing technology necessary for high resolution reservoir imaging.

  16. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2002-09-01

    Borehole seismology is the highest resolution geophysical imaging technique available to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This proposal takes direct aim at this shortcoming. P/GSI is developing a 400 level 3C clamped downhole seismic receiver array for borehole seismic 3D imaging. This array will remove the acquisition barrier to record the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore facilitate 9C reservoir imaging. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the fluid types. The data quality and the data volumes from a 400 level 3C array will allow us to develop the data processing technology necessary for high resolution reservoir imaging.

  17. Time-lapse 3-D seismic imaging of shallow subsurface contaminant flow.

    PubMed

    McKenna, J; Sherlock, D; Evans, B

    2001-12-01

    This paper presents a physical modelling study outlining a technique whereby buoyant contaminant flow within water-saturated unconsolidated sand was remotely monitored utilizing the time-lapse 3-D (TL3-D) seismic response. The controlled temperature and pressure conditions, along with the high level of acquisition repeatability attainable using sandbox physical models, allow the TL3-D seismic response to pore fluid movement to be distinguished from all other effects. TL3-D seismic techniques are currently being developed to monitor hydrocarbon reserves within producing reservoirs in an endeavour to improve overall recovery. However, in many ways, sandbox models under atmospheric conditions more accurately simulate the shallow subsurface than petroleum reservoirs. For this reason, perhaps the greatest application for analogue sandbox modelling is to improve our understanding of shallow groundwater and environmental flow mechanisms. Two fluid flow simulations were conducted whereby air and kerosene were injected into separate water-saturated unconsolidated sand models. In both experiments, a base 3-D seismic volume was recorded and compared with six later monitor surveys recorded while the injection program was conducted. Normal incidence amplitude and P-wave velocity information were extracted from the TL3-D seismic data to provide visualization of contaminant migration. Reflection amplitudes displayed qualitative areal distribution of fluids when a suitable impedance contrast existed between pore fluids. TL3-D seismic reflection tomography can potentially monitor the change in areal distribution of fluid contaminants over time, indicating flow patterns. However, other research and this current work have not established a quantifiable relationship between either normal reflection amplitudes and attenuation and fluid saturation. Generally, different pore fluids will have unique seismic velocities due to differences in compressibility and density. The predictable

  18. Imaging 3D anisotropic upper mantle shear velocity structure of Southeast Asia using seismic waveform inversion

    NASA Astrophysics Data System (ADS)

    Chong, J.; Yuan, H.; French, S. W.; Romanowicz, B. A.; Ni, S.

    2011-12-01

    Southeast Asia as a special region in the world which is seismically active and is surrounded by active tectonic belts, such as the Himalaya collision zone, western Pacific subduction zones and the Tianshan- Baikal tectonic belt. Seismic anisotropic tomography can shade light on the complex crust and upper mantle dynamics of this region, which is the subject of much debate. In this study, we applied full waveform time domain tomography to image 3D isotropic and anisotropic upper mantle shear velocity structure of Southeast Asia. Three component waveforms of teleseismic and far regional events (15 degree ≤ Δ≤ 165 degree) with magnitude ranges from Mw6.0 to Mw7.0 are collected from 91 permanent and 438 temporary broadband seismic stations in SE Asia. Wavepackets of both fundamental and overtone modes, filtered between 60 and 400 sec, are selected automatically according to the similarity between data and synthetic waveforms (Panning & Romanowicz, 2006). Wavepackets corresponding to event-station paths that sample the region considered are weighted according to path redundancy and signal to noise ratio. Higher modes and fundamental mode wavepackets are weighted separately in order to enhance the contribution of higher modes which are more sensitive to deeper structure compared to the fundamental mode. Synthetic waveforms and broadband sensitivity kernels are computed using normal mode asymptotic coupling theory (NACT, Li & Romanowicz, 1995). As a starting model, we consider a global anisotropic upper mantle shear velocity model based on waveform inversion using the Spectral Element Method (Lekic & Romanowicz, 2011), updated for more realistic crustal thickness (French et al., 2011) as our starting model, we correct waveforms for the effects of 3D structure outside of the region, and invert them for perturbations in the 3D structure of the target region only. We start with waveform inversion down to 60sec and after several iterations, we include shorter period

  19. Imaging 3D seismic velocity along the seismogenic zone of Algarve region (southern Portugal)

    NASA Astrophysics Data System (ADS)

    Rocha, João.; Bezzeghoud, Mourad; Caldeira, Bento; Dias, Nuno; Borges, José; Matias, Luís.; Dorbath, Catherine; Carrilho, Fernando

    2010-05-01

    The present seismic tomographic study is focused around Algarve region, in South of Portugal. To locate the seismic events and find the local velocity structure of epicentral area, the P and S arrival times at 38 stations are used. The data used in this study were obtained during the Algarve campaign which worked from January/2006 to July/2007. The preliminary estimate of origin times and hypocentral coordinates are determined by the Hypoinverse program. Linearized inversion procedure was applied to comprise the following two steps: 1) finding the minimum 1D velocity model using Velest and 2) simultaneous relocation of hypocenters and determination of local velocity structure. The velocity model we have reached is a 10 layer model which gave the lowest RMS, after several runnings of eight different velocity models that we used "a priori". The model parameterization assumes a continuous velocity field between 4.5 km/s and 7.0 km/s until 30 km depth. The earth structure is represented in 3D by velocity at discrete points, and velocity at any intervening point is determined by linear interpolation among the surrounding eight grid points. A preliminary analysis of the resolution capabilities of the dataset, based on the Derivative Weight Sum (DWS) distribution, shows that the velocity structure is better resolved in the West part of the region between the surface to15 km. The resulting tomographic image has a prominent low-velocity anomaly that shows a maximum decrease in P-wave velocity in the first 12 kms in the studied region. We also identified the occurrence of local seismic events of reduced magnitude not catalogued, in the neighbourhood of Almodôvar (low Alentejo). The spatial distribution of epicentres defines a NE-SW direction that coincides with the strike of the mapped geological faults of the region and issued from photo-interpretation. Is still expectable to refine the seismicity of the region of Almodôvar and establish more rigorously its role in the

  20. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-12-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  1. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2005-03-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  2. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-06-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  3. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2002-12-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  4. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-05-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  5. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2003-09-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  6. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS.

    SciTech Connect

    Bjorn N.P Paulsson

    2003-01-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  7. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  8. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2003-12-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  9. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2003-07-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  10. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-05-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  11. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N.P. Paulsson

    2005-08-21

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  12. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N. P. Paulsson

    2005-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  13. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N.P Paulsson

    2006-05-05

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  14. Evidence for the buried rim of Campi Flegrei caldera from 3-d active seismic imaging

    NASA Astrophysics Data System (ADS)

    Zollo, A.; Judenherc, S.; Auger, E.; D'Auria, L.; Virieux, J.; Capuano, P.; Chiarabba, C.; de Franco, R.; Makris, J.; Michelini, A.; Musacchio, G.

    2003-10-01

    An extended marine, active seismic survey has been performed on September, 2001 in the gulfs of Naples and Pozzuoli by recording about 5000 shots at a network of 62 sea bottom and 72 on shore seismographs. 3-D images of the shallow caldera structure are obtained from the tomographic inversion of about 77000 first P arrival times using the Benz et al. [1996] tomographic technique. The buried rim of the Campi Flegrei caldera is clearly detected at about 800-2000 m depth, as an anular high P-velocity and high density body. It has a diameter of about 8-12 km and a height of 1-2 km. According to stratigraphic and sonic log data from deep boreholes and tomographic P velocities, the rim is likely formed by solidified lavas and/or tuffs with interbedded lava. This study confirms the existence for a depressed limestone basement beneath the caldera at less than 4 km depth, while no evidence are found for shallower magmatic bodies.

  15. Imaging of 3-D seismic velocity structure of Southern Sumatra region using double difference tomographic method

    SciTech Connect

    Lestari, Titik; Nugraha, Andri Dian

    2015-04-24

    Southern Sumatra region has a high level of seismicity due to the influence of the subduction system, Sumatra fault, Mentawai fault and stretching zone activities. The seismic activities of Southern Sumatra region are recorded by Meteorological Climatological and Geophysical Agency (MCGA’s) Seismograph network. In this study, we used earthquake data catalog compiled by MCGA for 3013 events from 10 seismic stations around Southern Sumatra region for time periods of April 2009 – April 2014 in order to invert for the 3-D seismic velocities structure (Vp, Vs, and Vp/Vs ratio). We applied double-difference seismic tomography method (tomoDD) to determine Vp, Vs and Vp/Vs ratio with hypocenter adjustment. For the inversion procedure, we started from the initial 1-D seismic velocity model of AK135 and constant Vp/Vs of 1.73. The synthetic travel time from source to receiver was calculated using ray pseudo-bending technique, while the main tomographic inversion was applied using LSQR method. The resolution model was evaluated using checkerboard test and Derivative Weigh Sum (DWS). Our preliminary results show low Vp and Vs anomalies region along Bukit Barisan which is may be associated with weak zone of Sumatran fault and migration of partial melted material. Low velocity anomalies at 30-50 km depth in the fore arc region may indicated the hydrous material circulation because the slab dehydration. We detected low seismic seismicity in the fore arc region that may be indicated as seismic gap. It is coincides contact zone of high and low velocity anomalies. And two large earthquakes (Jambi and Mentawai) also occurred at the contact of contrast velocity.

  16. Imaging of 3-D seismic velocity structure of Southern Sumatra region using double difference tomographic method

    NASA Astrophysics Data System (ADS)

    Lestari, Titik; Nugraha, Andri Dian

    2015-04-01

    Southern Sumatra region has a high level of seismicity due to the influence of the subduction system, Sumatra fault, Mentawai fault and stretching zone activities. The seismic activities of Southern Sumatra region are recorded by Meteorological Climatological and Geophysical Agency (MCGA's) Seismograph network. In this study, we used earthquake data catalog compiled by MCGA for 3013 events from 10 seismic stations around Southern Sumatra region for time periods of April 2009 - April 2014 in order to invert for the 3-D seismic velocities structure (Vp, Vs, and Vp/Vs ratio). We applied double-difference seismic tomography method (tomoDD) to determine Vp, Vs and Vp/Vs ratio with hypocenter adjustment. For the inversion procedure, we started from the initial 1-D seismic velocity model of AK135 and constant Vp/Vs of 1.73. The synthetic travel time from source to receiver was calculated using ray pseudo-bending technique, while the main tomographic inversion was applied using LSQR method. The resolution model was evaluated using checkerboard test and Derivative Weigh Sum (DWS). Our preliminary results show low Vp and Vs anomalies region along Bukit Barisan which is may be associated with weak zone of Sumatran fault and migration of partial melted material. Low velocity anomalies at 30-50 km depth in the fore arc region may indicated the hydrous material circulation because the slab dehydration. We detected low seismic seismicity in the fore arc region that may be indicated as seismic gap. It is coincides contact zone of high and low velocity anomalies. And two large earthquakes (Jambi and Mentawai) also occurred at the contact of contrast velocity.

  17. A 3-D spectral-element and frequency-wave number hybrid method for high-resolution seismic array imaging

    NASA Astrophysics Data System (ADS)

    Tong, Ping; Komatitsch, Dimitri; Tseng, Tai-Lin; Hung, Shu-Huei; Chen, Chin-Wu; Basini, Piero; Liu, Qinya

    2014-10-01

    We present a three-dimensional (3-D) hybrid method that interfaces the spectral-element method (SEM) with the frequency-wave number (FK) technique to model the propagation of teleseismic plane waves beneath seismic arrays. The accuracy of the resulting 3-D SEM-FK hybrid method is benchmarked against semianalytical FK solutions for 1-D models. The accuracy of 2.5-D modeling based on 2-D SEM-FK hybrid method is also investigated through comparisons to this 3-D hybrid method. Synthetic examples for structural models of the Alaska subduction zone and the central Tibet crust show that this method is capable of accurately capturing interactions between incident plane waves and local heterogeneities. This hybrid method presents an essential tool for the receiver function and scattering imaging community to verify and further improve their techniques. These numerical examples also show the promising future of the 3-D SEM-FK hybrid method in high-resolution regional seismic imaging based on waveform inversions of converted/scattered waves recorded by seismic array.

  18. 3D seismic imaging around the 2.5 km deep COSC-1 scientific borehole, central Sweden

    NASA Astrophysics Data System (ADS)

    Hedin, Peter; Juhlin, Christopher; Buske, Stefan

    2015-04-01

    Following the successful completion of the COSC-1 drilling campaign, a number of geophysical investigations have been performed in and around the 2.5 km deep borehole. Three different seismic experiments were conducted simultaneously in the fall of 2014 to take advantage of the same source points; 1) a Vertical Seismic Profile (VSP) in the borehole, 2) three 2D seismic profiles across the borehole, and 3) a limited 3D seismic survey (presented here). The latter is the first 3D seismic survey on land in Scandinavia to target the Caledonian Nappes and will allow mapping a small part of the Seve Nappe Complex (SNC) in 3D. Furthermore, it will allow extrapolation of results from downhole logging, core analysis and other seismic surveys to structures surrounding the borehole. A total number of 429 receivers (10 Hz single component geophones) were planted with 20 m separation along 7 lines spaced 200 m apart. The total area with receivers covered approximately 1.5 km2 and was centered on the drill site. A combination of a mechanical source (a rock breaking hydraulic hammer, near offsets) and explosive charges (0.5 kg fired at 3.5 - 5 m depth, far offsets) were used. The source points were activated along roads radiating outwards from the COSC-1 drill site in a star pattern. The nominal shot spacing was 20 m (vibrating source) or 80 m (explosives) and maximum horizontal offset was about 5.75 km. The high-grade metamorphic SNC is well known from previous 2D seismic studies to be a highly reflective unit. However, due to the complex 3D geometry and lithological variation within the unit, it has not been clearly imaged. The new 3D data provide a means to image these structures in more detail and to follow the lithological and structural interfaces observed in the core into the surrounding unit. Preliminary results from the 3D processing and correlation with borehole data will be presented.

  19. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  20. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N. P. Paulsson

    2006-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to perform high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology has been hampered by the lack of acquisition technology necessary to record large volumes of high frequency, high signal-to-noise-ratio borehole seismic data. This project took aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array has removed the technical acquisition barrier for recording the data volumes necessary to do high resolution 3D VSP and 3D cross-well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that promise to take the gas industry to the next level in their quest for higher resolution images of deep and complex oil and gas reservoirs. Today only a fraction of the oil or gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of detailed compartmentalization of oil and gas reservoirs. In this project, we developed a 400 level 3C borehole seismic receiver array that allows for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. This new array has significantly increased the efficiency of recording large data volumes at sufficiently dense spatial sampling to resolve reservoir complexities. The receiver pods have been fabricated and tested to withstand high temperature (200 C/400 F) and high pressure (25,000 psi), so that they can operate in wells up to 7,620 meters (25,000 feet) deep. The receiver array is deployed on standard production or drill tubing. In combination with 3C surface seismic or 3C borehole seismic sources, the 400

  1. Enhanced imaging of CO2 at the Ketzin storage site: Inversion of 3D time-lapse seismic data

    NASA Astrophysics Data System (ADS)

    Gil, M.; Götz, J.; Ivanova, A.; Juhlin, C.; Krawczyk, C. M.; Lüth, S.; Yang, C.

    2012-04-01

    The Ketzin test site, located near Berlin, is Europe's longest-operating on-shore CO2 storage site. As of December 2011, more than 56,000 tons of food grade CO2 has been injected since June 2008 in an anticlinal structure of the Northeast German Basin. The target reservoir consists of porous, brine bearing sandstone units of the Upper Triassic Stuttgart Formation at approximately 630 to 650 m depth. In order to enhance the understanding of the structural geometry of the site and to investigate the extension of the CO2-plume, several geophysical monitoring methods are being applied at Ketzin, among these are active seismic measurements, geoelectrics and borehole measurements. Among the various seismic techniques (e.g. 2D reflection surveys, crosshole tomography, Vertical Seismic Profiling, 2D- and 3D-Moving Source Profiling) employed at this pilot site, 3D time-lapse reflection surveys are an important component. The baseline 3D survey was acquired in 2005 and the first repeat measurements were performed in 2009 after injection of about 22,000 tons of CO2. The second repeat survey is planned to be carried out in fall 2012. These measurements allow the time-lapse signature of the injected CO2 to be imaged. The time-lapse amplitude variation attributed to the injected CO2 in the reservoir matches, considering detection limits of seismic surface measurements, the expected distribution of the CO2 plume derived from reservoir simulations. Previous attempts towards a quantitative interpretation were based on integrative considerations of different types of geophysical measurements using strict assumptions and characterized by large error bars. In order to increase the resolution and reliability of the data and to improve estimation of rock properties and especially to enhance the imaging resolution of the CO2-plume, the time-lapse 3D seismic data have now been inverted for seismic impedances with different methods, which is the focus of this presentation. One difficulty

  2. 3-D Seismic Images of Mud Volcano North Alex, West-Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Bialas, J.; Klaeschen, D.; Papenberg, C. A.; Gehrmann, R.; Sommer, M.

    2009-12-01

    Mud volcanoes within shelf areas are the bathymetric expression of mobilized overpressured sediments causing a feature of possible instability within the slope. Such a scene is given in the West-Nile Delta offshore Alexandria, Egypt at 700 m water depth. The West Nile Delta forms part of the source of the large turbiditic Nile Deep Sea Fan. Since the late Miocene sediments have formed an up to 10 km thick pile, which includes about 1 - 3 km of Messinian evaporates. The sediment load of the overburden implies strong overpressures and salt-related tectonic deformation. Both are favourable for fluid migration towards the seafloor guided by the fractured margin. Deep-cutting channel systems like the Rosetta channel characterize the continental slope. Bathymetric expressions of slides and numerous mud volcanoes in the area are expressions of active processes, which contribute to the ongoing modification of the slope. The western deltaic system, Rosetta branch, has formed an 80 km wide continental shelf. Here at 700 m water depth the mud volcano North Alex developed his circular bathymetric feature, which proved to be an active gas and mud-expelling structure. A grid of 2-D seismic profiles did reveal a large set of faults located within the main mud volcano as well as surrounding the structure. Internal faults are mainly related to episodic mud expulsion processes and continuous gas and fluid production. Deep cutting external faults surround the structure in a half circle shape. They can be tracked up to the seafloor indicating ongoing tectonic activity of the slope area. A recently build 3-D acquisition system suitable for mid-size research vessels was applied to collect an active seismic cube of the mud volcano. Based on the P-Cable design 11 parallel streamers (each 12.5 m long with 1.5 m group interval) were used to record shots of a single 210 cinch GI airgun. After stacking a 3D time migration within the cube provided final signal to noise reduction and filled

  3. 3-D Seismic Images of Mud Volcano North Alex, West-Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Bialas, Joerg; Klaeschen, Dirk; Papenberg, Cord; Gehrmann, Romina; Sommer, Malte

    2010-05-01

    Mud volcanoes within shelf areas are the bathymetric expression of mobilized overpressured sediments causing a feature of possible instability within the slope. Such a scene is given in the West-Nile Delta offshore Alexandria, Egypt at 700 m water depth, ,which was studied during a RWE Dea funded research project. The West Nile Delta forms part of the source of the large turbiditic Nile Deep Sea Fan. Since the late Miocene sediments have formed an up to 10 km thick pile, which includes about 1 - 3 km of Messinian evaporates. The sediment load of the overburden implies strong overpressures and salt-related tectonic deformation. Both are favourable for fluid migration towards the seafloor guided by the fractured margin. Deep-cutting channel systems like the Rosetta channel characterize the continental slope. Bathymetric expressions of slides and numerous mud volcanoes in the area are expressions of active processes, which contribute to the ongoing modification of the slope. The western deltaic system, Rosetta branch, has formed an 80 km wide continental shelf. Here at 700 m water depth the mud volcano North Alex developed his circular bathymetric feature, which proved to be an active gas and mud-expelling structure. A grid of 2-D seismic profiles did reveal a large set of faults located within the main mud volcano as well as surrounding the structure. Internal faults are mainly related to episodic mud expulsion processes and continuous gas and fluid production. Deep cutting external faults surround the structure in a half circle shape. They can be tracked up to the seafloor indicating ongoing tectonic activity of the slope area. A recently build 3-D acquisition system (funded by RWE Dea) suitable for mid-size research vessels was applied to collect an active seismic cube of the mud volcano. Based on the P-Cable design 11 parallel streamers (each 12.5 m long with 1.5 m group interval) were used to record shots of a single 210 cinch GI airgun. Based on GPS positions of

  4. 3D Elastic Seismic Wave Propagation Code

    1998-09-23

    E3D is capable of simulating seismic wave propagation in a 3D heterogeneous earth. Seismic waves are initiated by earthquake, explosive, and/or other sources. These waves propagate through a 3D geologic model, and are simulated as synthetic seismograms or other graphical output.

  5. High-resolution 3D seismic imaging of a pull-apart basin in the Gulf of Cadiz

    NASA Astrophysics Data System (ADS)

    Crutchley, G.; Berndt, C.; Klaeschen, D.; Gutscher, M.

    2009-12-01

    In 2006, high-resolution 3D seismic data were acquired in the Gulf of Cadiz and the Mediterranean Sea aboard the RRS Charles Darwin as part of the HERMES (Hotspot Ecosystem Research on the Margins of European Seas) project. The P-Cable system, a cost-efficient set-up for fast acquisition of 3D seismic data on 12 single-channel streamers, was utilized to acquire seismic cubes at four different targets. Here, we present results from the second target - a WNW-ESE-oriented pull-apart basin in the southeastern Gulf of Cadiz. Initial processing has included: 1) spatial positioning of each recording channel from GPS data acquired on the outer two channels, 2) improved positioning of shot points and channels from the inversion of first arrival times, 3) application of a swell filter to improve reflection coherency, 4) CDP binning and stacking and 5) migration. The new data confirm that the southeastern Gulf of Cadiz north of the Rharb submarine valley is structurally controlled by numerous strike slip faults that were active until quite recently (within the resolution of the data). Given the location of this basin, between the extensional domain on the upper slope and the compressional toe of the accretionary wedge, we interpret the origin to be gravitational sliding on a detachment layer, possibly containing salt, but at this stage not imaged by our profiles.

  6. SHEAR WAVE SEISMIC STUDY COMPARING 9C3D SV AND SH IMAGES WITH 3C3D C-WAVE IMAGES

    SciTech Connect

    John Beecherl; Bob A. Hardage

    2004-07-01

    The objective of this study was to compare the relative merits of shear-wave (S-wave) seismic data acquired with nine-component (9-C) technology and with three-component (3-C) technology. The original proposal was written as if the investigation would be restricted to a single 9-C seismic survey in southwest Kansas (the Ashland survey), on the basis of the assumption that both 9-C and 3-C S-wave images could be created from that one data set. The Ashland survey was designed as a 9-C seismic program. We found that although the acquisition geometry was adequate for 9-C data analysis, the source-receiver geometry did not allow 3-C data to be extracted on an equitable and competitive basis with 9-C data. To do a fair assessment of the relative value of 9-C and 3-C seismic S-wave data, we expanded the study beyond the Ashland survey and included multicomponent seismic data from surveys done in a variety of basins. These additional data were made available through the Bureau of Economic Geology, our research subcontractor. Bureau scientists have added theoretical analyses to this report that provide valuable insights into several key distinctions between 9-C and 3-C seismic data. These theoretical considerations about distinctions between 3-C and 9-C S-wave data are presented first, followed by a discussion of differences between processing 9-C common-midpoint data and 3-C common-conversion-point data. Examples of 9-C and 3-C data are illustrated and discussed in the last part of the report. The key findings of this study are that each S-wave mode (SH-SH, SV-SV, or PSV) involves a different subsurface illumination pattern and a different reflectivity behavior and that each mode senses a different Earth fabric along its propagation path because of the unique orientation of its particle-displacement vector. As a result of the distinct orientation of each mode's particle-displacement vector, one mode may react to a critical geologic condition in a more optimal way than do

  7. 3-D Velocity Model of the Coachella Valley, Southern California Based on Explosive Shots from the Salton Seismic Imaging Project

    NASA Astrophysics Data System (ADS)

    Persaud, P.; Stock, J. M.; Fuis, G. S.; Hole, J. A.; Goldman, M.; Scheirer, D. S.

    2014-12-01

    We have analyzed explosive shot data from the 2011 Salton Seismic Imaging Project (SSIP) across a 2-D seismic array and 5 profiles in the Coachella Valley to produce a 3-D P-wave velocity model that will be used in calculations of strong ground shaking. Accurate maps of seismicity and active faults rely both on detailed geological field mapping and a suitable velocity model to accurately locate earthquakes. Adjoint tomography of an older version of the SCEC 3-D velocity model shows that crustal heterogeneities strongly influence seismic wave propagation from moderate earthquakes (Tape et al., 2010). These authors improve the crustal model and subsequently simulate the details of ground motion at periods of 2 s and longer for hundreds of ray paths. Even with improvements such as the above, the current SCEC velocity model for the Salton Trough does not provide a match of the timing or waveforms of the horizontal S-wave motions, which Wei et al. (2013) interpret as caused by inaccuracies in the shallow velocity structure. They effectively demonstrate that the inclusion of shallow basin structure improves the fit in both travel times and waveforms. Our velocity model benefits from the inclusion of known location and times of a subset of 126 shots detonated over a 3-week period during the SSIP. This results in an improved velocity model particularly in the shallow crust. In addition, one of the main challenges in developing 3-D velocity models is an uneven stations-source distribution. To better overcome this challenge, we also include the first arrival times of the SSIP shots at the more widely spaced Southern California Seismic Network (SCSN) in our inversion, since the layout of the SSIP is complementary to the SCSN. References: Tape, C., et al., 2010, Seismic tomography of the Southern California crust based on spectral-element and adjoint methods: Geophysical Journal International, v. 180, no. 1, p. 433-462. Wei, S., et al., 2013, Complementary slip distributions

  8. 3D imaging of the Corinth rift from a new passive seismic tomography and receiver function analysis

    NASA Astrophysics Data System (ADS)

    Godano, Maxime; Gesret, Alexandrine; Noble, Mark; Lyon-Caen, Hélène; Gautier, Stéphanie; Deschamps, Anne

    2016-04-01

    The Corinth Rift is the most seismically active zone in Europe. The area is characterized by very localized NS extension at a rate of ~ 1.5cm/year, the occurrence of frequent and intensive microseismic crises and occasional moderate to large earthquakes like in 1995 (Mw=6.1). Since the year 2000, the Corinth Rift Laboratory (CRL, http://crlab.eu) consisting in a multidisciplinary natural observatory, aims at understanding the mechanics of faulting and earthquake nucleation in the Rift. Recent studies have improved our view about fault geometry and mechanics within CRL, but there is still a critical need for a better knowledge of the structure at depth both for the accuracy of earthquake locations and for mechanical interpretation of the seismicity. In this project, we aim to analyze the complete seismological database (13 years of recordings) of CRL by using recently developed methodologies of structural imaging, in order to determine at the same time and with high resolution, the local 3D structure and the earthquake locations. We perform an iterative joint determination of 3D velocity model and earthquake coordinates. In a first step, P and S velocity models are determined using first arrival time tomography method proposed by Taillandier et al. (2009). It consists in the minimization of the cost function between observed and theoretical arrival times which is achieved by the steepest descent method (e.g. Tarantola 1987). This latter requires computing the gradient of the cost function by using the adjoint state method (Chavent 1974). In a second step, earthquakes are located in the new velocity model with a non-linear inversion method based on a Bayesian formulation (Gesret et al. 2015). Step 1 and 2 are repeated until the cost function no longer decreases. We present preliminary results consisting in: (1) the adjustement of a 1D velocity model that is used as initial model of the 3D tomography and (2) a first attempt of the joint determination of 3D velocity

  9. 3D Seismic Reflection Imaging of Crustal Formation Processes on the East Pacific Rise, 9°57-42'N

    NASA Astrophysics Data System (ADS)

    Purdy, G. M.; Mutter, J. C.; Carbotte, S. M.; Canales, J. P.; Nedimovic, M. R.; Carton, H.; Newman, K. R.; Marjanovic, M.; Xu, M.; Aghaei, O.; Stowe, L. C.

    2008-12-01

    Between June 29th and August 19th 2008 the research vessel Marcus G Langseth carried out its first multi- streamer 3D seismic reflection imaging cruise, MGL08-12, by conducting a program research on the East Pacific Rise centered around 9°50'N. The primary goals were to create an accurate 3D seismic reflection image of the magmatic-hydrothermal system at this Integrated Study Site of the Ridge2000 program by imaging the structure of the axial magma chamber (AMC) lid and oceanic crust at a resolution, accuracy, and scale comparable to seafloor observations. The vessel acquired data with four, 6-kilometer solid streamers each comprising 468 active channels deployed with a total separation of 450 meters. Four gun strings with total volume of 3300 cubic inches in two groups fired alternately provide the source for a shot spacing of 37.5 meters. This configuration yields eight CMP lines for each of the sail lines that were spaced 300 m apart, and a static bin size of 6.25 m × 37.5 m in the along-track and across-track directions, respectively, providing a nominal fold of 40. The cruise accomplished the acquisition of ~3,782 km of sail line data. There are 111 across axis lines that required 10 repeated lines and 14 infills. Average feathering during the cruise was 0° ± 5° (one standard deviation), with maximum values of up to 11°. This means that 18% of the total cross axis acquisition was needed for reshoots and infilling. A 25% multiplier on planned lines for a 3D grid is probably a useful figure to use in cruise planning and is fairly standard in the seismic industry. Data quality meets or exceeds industry standards. 3D coverage was achieved in two areas. The larger comprises a set of 93 equally spaced lines forming the 3D grid between 9°57'N and 9°42'N. This grid is made up of lines from all of racetracks #1 and #2 and the northern lines of racetrack#3 and covers two principal hydrothermal vent areas in a continuous fashion. The second 3D area is comprised

  10. Newly discovered abundant fluid seep indicators off southern Costa Rica, imaged from overlapping multibeam swaths and 3D seismic data

    NASA Astrophysics Data System (ADS)

    Kluesner, J. W.; Silver, E. A.; Gibson, J. C.; Bangs, N. L.; McIntosh, K.; von Huene, R.; Orange, D.; Ranero, C. R.

    2012-12-01

    Offshore southern Costa Rica we have identified 161 potential fluid seepage sites on the shelf and slope regions within an 11 x 55 km strip where no fluid indicators had been reported previously using conventional deep-water mutlibeam bathymetry (100 m grid cell size) and deep towed side scan sonar. Evidence includes large and small pockmarks, mounds, ridges, and slope failure features with localized anomalous high-amplitude backscatter strength. The majority of seepage indicators are associated with shallow sub-bottom reversed polarity bright spots and flat spots imaged within the CRISP 3D seismic grid. Data were collected ~50 km west of Osa Peninsula, Costa Rica onboard the R/V Marcus G. Langseth during the spring of 2011. We obtained EM122 multibeam data using fixed, closely spaced receiver beams and 9-10 times swath overlap, which greatly improved the signal-to-noise ratio and sounding density and allowed for very small grid and mosaic cell sizes (2-10 m). A gas plume in the water column, seen on a 3.5 kHz profile, is located along a fault trace and above surface and subsurface seep indicators. Fluid indicators on the outer shelf occur largely on a dense array of faults, some of which cut through the reflective basement. Seismic flat spots commonly underlie axes of large anticlines on the shelf and slope. Pockmarks are also located at the foot of mid-slope canyons, very near to the upper end of the BSR. These pockmarks appear to be associated with canyon abandonment and folded beds that channel fluids upward, causing hydrate instability. Our findings suggest that significant amounts of methane are venting into ocean and potentially into the atmosphere across the heavily deformed shelf and slope of Costa Rica.

  11. Characterization of the Hontomín Research Facility for Geological Storage of CO2: 3D Seismic Imaging Results

    NASA Astrophysics Data System (ADS)

    Alcalde, J.; Martí, D.; Juhlin, C.; Malehmir, A.; Calahorrano, A.; Ayarza, P.; Pérez-Estaún, A.; Carbonell, R.

    2012-04-01

    A technological research facility dedicated to the underground geological storage of CO2 is currently being developed by the Spanish research program on Carbon Capture and Storage (CCS) in Hontomin (Burgos). This research program is being developed by the CIUDEN Foundation, an initiative launched by 3 Spanish state departments (Science & Innovation, Environment and Industry). An extensive multidisciplinary site characterization phase has been carried out, including a multiseismic data acquisition experiment. Within this effort, a 36 km2 3D seismic reflection survey was acquired in the summer of 2010. Its aim was to provide high resolution images of the subsurface of the storage complex, as well as to provide a baseline model for all the disciplines involved in the project. The target reservoir is a saline aquifer located at 1400 m, approximately, within Lower Jurassic carbonates (Lias). The main seal is formed by inter-layered marls and marly limestones of Early to Middle Jurassic age (Dogger and Lias). The main acquisition characteristics of the survey included (1) a mixed source of vibroseis and explosives with 74% and 26% of each used, respectively, (2) 5000 source points distributed along 22 source lines (separated 250 m) and (3) 22 lines of receivers (separated 275 m). Shot and receiver spacing along the source and receiver lines was 25 m, resulting in a nominal CDP-fold of 36 for 13 m2 bins. The 3D-data have been fully processed to post stack migration. The most critical processing steps included static correction calculations, time variant frequency filtering, rms velocity analysis, F-XY deconvolution, dip move-out correction, residual statics calculations and post stack migration. The final high-resolution 3D-volume shows the shape and depth of the primary reservoir-seal system, the main faults of the area and the secondary reservoir-seal sequence. It allows us to characterize the main tectonic structure of the dome complex, the fault system of the area and

  12. A comparative study between a rectilinear 3-D seismic survey and a concentric-circle 3-D seismic survey

    SciTech Connect

    Maldonado, B.; Hussein, H.S.

    1994-12-31

    Due to the rectilinear nature of the previous 3D seismic survey, the details necessary for proper interpretation were absent. Theoretically, concentric 3D seismic technology may provide an avenue for gaining more and higher quality data coverage. Problems associated with recording a rectilinear 3D seismic grid over the salt dome in this area have created the need to investigate the use of such procedures as the concentric-circle 3D seismic acquisition technique. The difficulty of imaging salt dome flanks with conventional rectilinear 3D seismic may be a result of the inability to precisely predict the lateral velocity-field variation adjacent to both salt and sediments. The dramatic difference in the interval velocities of salt and sediments causes the returning ray to severely deviate from being a hyperbolic path. This hampers the ability to predict imaging points near the salt/sediment interface. Perhaps the most difficult areas to image with rectilinear seismic surveys are underneath salt overhangs. Modeling suggests that a significant increase in the number of rays captured from beneath a salt overhang can be achieved with the concentric-circle method. This paper demonstrates the use of the ``circle shoot`` on a survey conducted over a salt dome in the Gulf of Mexico. A total of 80 concentric circles cover an area which is equivalent to 31,000 acres. The final post-stack data were sorted into bins with dimensions of 25 meters by 25 meters. A comparison of 3D rectilinear shooting vs. 3D concentric circle shooting over the same area will show an improvement in data quality and signal-to-noise characteristics.

  13. Heterodyne 3D ghost imaging

    NASA Astrophysics Data System (ADS)

    Yang, Xu; Zhang, Yong; Yang, Chenghua; Xu, Lu; Wang, Qiang; Zhao, Yuan

    2016-06-01

    Conventional three dimensional (3D) ghost imaging measures range of target based on pulse fight time measurement method. Due to the limit of data acquisition system sampling rate, range resolution of the conventional 3D ghost imaging is usually low. In order to take off the effect of sampling rate to range resolution of 3D ghost imaging, a heterodyne 3D ghost imaging (HGI) system is presented in this study. The source of HGI is a continuous wave laser instead of pulse laser. Temporal correlation and spatial correlation of light are both utilized to obtain the range image of target. Through theory analysis and numerical simulations, it is demonstrated that HGI can obtain high range resolution image with low sampling rate.

  14. Joint inversion of 3-D seismic, gravimetric and magnetotelluric data for sub-basalt imaging in the Faroe-Shetland Basin

    NASA Astrophysics Data System (ADS)

    Heincke, B.; Moorkamp, M.; Jegen, M.; Hobbs, R. W.

    2012-12-01

    Imaging of sub-basalt sediments with reflection seismic techniques is limited due to absorption, scattering and transmission effects and the presence of peg-leg multiples. Although many of the difficulties facing conventional seismic profiles can be overcome by recording long offset data resolution of sub-basalt sediments in seismic sections is typically still largely restricted. Therefore multi-parametric approaches in general and joint inversion strategies in particular (e.g. Colombo et al., 2008, Jordan et al., 2012) are considered as alternative to gain additional information from sub-basalt structures. Here, we combine in a 3-D joint inversion first-arrival time tomography, FTG gravity and MT data to identify the base basalt and resolve potential sediments underneath. For sub-basalt exploration the three methods complement each other such that the null space is reduced and significantly better resolved models can be obtained than would be possible by the individual methods: The seismic data gives a robust model for the supra-basalt sediments whilst the gravity field is dominated by the high density basalt and basement features. The MT on the other hand is sensitive to the conductivity in both the supra- and sub-basalt sediments. We will present preliminary individual and joint inversion result for a FTG, seismic and MT data set located in the Faroe-Shetland basin. Because the investigated area is rather large (~75 x 40 km) and the individual data sets are relatively huge, we use a joint inversion framework (see Moorkamp et al., 2011) which is designed to handle large amount of data/model parameters. This program has moreover the options to link the individual parameter models either petrophysically using fixed parameter relationships or structurally using the cross-gradient approach. The seismic data set consists of a pattern of 8 intersecting wide-angle seismic profiles with maximum offsets of up to ~24 km. The 3-D gravity data set (size :~ 30 x 30 km) is

  15. Fold Thrust Belt Kinematics from 3D Seismic Imaging along the NanTroSEIZE Transect, Nankai Accretionary Prism, Japan.

    NASA Astrophysics Data System (ADS)

    Kington, J. D.; Tobin, H.; Moore, G.

    2008-12-01

    The accretionary prism of the Nankai Trough, Japan provides an excellent location to study the kinematics of a fold and thrust belt developed primarily in low permeability units. Recently acquired 3D reflection seismic data covering a 12 x 56 km area from the Kumano basin seaward to the deformation front reveals three structural domains within the frontal accretionary prism. The farthest seaward domain of the prism consists closely-spaced, apparently in-sequence thrust sheets forming a steep critical taper angle. The primary decollement beneath these thrusts ramps upsection above a topographic high within the oceanic basement. The farthest landward domain within the study area consists of the hanging wall of an apparently out of sequence megasplay thrust fault that dips landward to the top of the oceanic crust. The central structural domain within the prism consists of thrust sheets formed above a decollement approximately 2 km above the top of the oceanic crust, above the decollement associated with the more seaward thrusts. These thrusts are more widely spaced than those nearer the deformation front and are blanketed with syn and post kinematic sediments. Synkinematic sediments indicate that thrusts in the most seaward and most landward structural domains within the prism are the most active, though some reactivation of structures in the middle domain has occurred. Additionally, gas hydrate bottom simulating reflectors (BSRs) in the lowermost portions of the prism are present as discrete bands striking parallel to thrusts. These BSRs occur primarily along the most active thrusts, and are only present as small patches within the central structural domain of the prism. As these are expected to be the result of fluid migration along faults and permeable structures, they provide insight into the hydrologic controls on thrusting within the accretionary prism.

  16. 3D Seismic Reflection Images of An Off-Axis Melt Lens And Its Associated Upper Crust Around 9°39'N, East Pacific Rise

    NASA Astrophysics Data System (ADS)

    Han, S.; Carton, H. D.; Carbotte, S. M.; Mutter, J. C.; Canales, J.; Nedimović, M. R.

    2011-12-01

    During the 3D multi-channel seismic (MCS) survey MGL0812 aboard the R/V Langseth, several mid-crust reflectors were discovered off axis on both flanks of the East Pacific Rise from 9°35.6-57.0'N. The reversed polarity of these off-axis reflections with respect to the seafloor and Moho reflections and the high attenuation of the crust detected beneath two of them in the north suggest that they arise from melts residing at the mid-crust level outside the axial low velocity zone (Canales et al. 2010). These off-axis melt lenses (OAML) are probable sites of off-axis volcanism and potential heat sources for localized hydrothermal circulation on the ridge flanks. We focus here on a prominent OAML discovered on the eastern flank around 9°39'N. Results from 1D travel time modeling and 2D streamer tomography of downward continued shot gathers show the presence of a thinner seismic layer 2A above the center of the OAML compared with its surrounding crust. We attribute this thinning to the effects of alteration associated with localized off-axis hydrothermal circulation driven by the OAML, where precipitation of secondary minerals infills pore space within the lower basalt section, leading to increased seismic velocities and thereby converting the lowermost seismic layer 2A into seismic layer 2B. To further constrain the respective 3D geometries of the OAML and the AMC, their spatial relations, and the spatial extent and shape of the region of altered upper crust associated with the OAML, we conduct 3D processing of a small MCS grid that encompasses most of this OAML, aimed at imaging both on- and off-axis melt lens events and the base of seismic layer 2A. This grid covers an ~4 km x 24 km area centered on the ridge crest between ˜9°37.5'-40'N and extending on both flanks, within which a third order ridge axis discontinuity and two high temperature hydrothermal vents identified during Alvin dives in 1991 and 1994 are present. The data were recorded by four 468-channel

  17. Record of Subducting Topography revealed in 3D Seismic Imaging of Pleistocene unconformities, offshore Southern Costa Rica

    NASA Astrophysics Data System (ADS)

    Edwards, J. H.; Kluesner, J. W.; Silver, E. A.

    2015-12-01

    3D seismic reflection data (CRISP) collected across the southern Costa Rica forearc reveals broad, survey-wide erosional events in the upper ~1 km of slope sediments in the mid-slope to outer shelf. The upper 0-280 m of continuous, weakly deformed sediments, designated by IODP Expedition 344 as structural domain I, is bounded by a major erosional event, (CRISP-U1, dated near 1 Ma), suggesting wave-plain erosion from the present shelf break out to 25 km seaward, to a present-day water depth of 900-1300 m. The eastern toe of its surface is characterized by a large drainage system, likely including submarine channels that eroded to depths >1500 m below present-day water depth. CRISP-U1 is variably uplifted by a series of fault propagation folds and cut by an intersecting array of normal faults. Another, major erosional event, (CRISP-M1, approximately 2 Ma) extended from the outer shelf to the mid slope and removed 500-1000 m of material. Overlying CRISP-M1 is up to 1 km of sediments that are more deformed by fault propagation folds, back thrusts, and intersecting arrays of normal faults. Unconformities with smaller areal extent are variably found in these overlying sediments across the mid-slope to outer shelf, at present-day water depths >220 m. Below CRISP-M1, sediments are more densely deformed and also contain major unconformities that extend survey-wide. Both unconformities, CRISP-U1 and CRISP-M1, are encountered in well U1413 and are demarcated by major benthic foraminifera assemblage changes at 149 mbsf and ~504 mbsf (Harris et al., 2013, Proceeding of the IODP, Volume 344).CRISP-M1 is likely correlative to the major sediment facies and benthic foraminifera assemblage change found in U1379 at ~880 mbsf (Vannuchi et al., 2013). The unconformities and intersecting array of normal faults may demarcate the passing of topography on the downgoing Cocos plate, episodically lifting and then subsiding the Costa Rica margin, with amplitudes up to about 1 km.

  18. Deep reflection structure imaged by the 2008 3D seismic reflection Survey at the RIDGE- 2000 East Pacific Rise Integrated Studies Site

    NASA Astrophysics Data System (ADS)

    Nedimović, M. R.; Carbotte, S. M.; Mutter, J. C.; Canales, P. J.; Carton, H.; Aghaei, O.; Marjanović, M.; Newman, K. R.; Hu, M.; Stowe, L.

    2008-12-01

    The first multi-source and multi-streamer 3D seismic reflection experiment carried out using academic resources was done aboard the R/V Marcus G. Langseth in Summer 2008 during cruise MGL0812. The targeted area was the RIDGE-2000 Integrated Studies Site at the East Pacific Rise. Our primary 3D survey grid extends from about 9° 57'N to 9° 42'N, with a smaller grid just to the south covering approximately from 9° 40'N to 9° 37.5'N. Additionally, about 1 and 0.5 km wide across-ridge-axis swaths of data were collected at 9° 36'N and 9°30'N respectively, as well as an along-ridge-axis swath about 1 km wide and extending from 10° 05'N to 9° 40'N. We here focus on a preliminary analysis of the reflection structure imaged within the lower crust and uppermost mantle. Moho reflection arrivals are imaged through much of the investigated area. The character of Moho reflection events varies from simple, single reflection wavelet to more complex arrivals indicating spatial changes in structure within the Moho transition zone. Particularly strong Moho reflections are observed in the southern half of the main 3D grid. In places, Moho reflection event appears to extend across the ridge axis potentially suggesting "zero-age" Moho development. Weak Moho arrivals are found at the north end of the main 3D box and within the smaller box to the south. Most notable place lacking Moho reflections is the Lamont seamount area where Moho is not observed on either side of the ridge axis, although the area lacking Moho reflections is wider on the western ridge flank. Further south, along the across-ridge-axis swaths, Moho reflections again become more pronounced. A suit of what mostly appear to be reflection events is recognized between the AMC and Moho. Many of them do not appear to be multiples, and their origin is not well understood. Possible origins for these events include: lower boundary of the AMC, S-converted waves, and lower crustal melt lenses. Along sections of the two 3D

  19. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, R.N.; Boulanger, A.; Bagdonas, E.P.; Xu, L.; He, W.

    1996-12-17

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells. 22 figs.

  20. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, Roger N.; Boulanger, Albert; Bagdonas, Edward P.; Xu, Liqing; He, Wei

    1996-01-01

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells.

  1. 3D VSP imaging in the Deepwater GOM

    NASA Astrophysics Data System (ADS)

    Hornby, B. E.

    2005-05-01

    Seismic imaging challenges in the Deepwater GOM include surface and sediment related multiples and issues arising from complicated salt bodies. Frequently, wells encounter geologic complexity not resolved on conventional surface seismic section. To help address these challenges BP has been acquiring 3D VSP (Vertical Seismic Profile) surveys in the Deepwater GOM. The procedure involves placing an array of seismic sensors in the borehole and acquiring a 3D seismic dataset with a surface seismic gunboat that fires airguns in a spiral pattern around the wellbore. Placing the seismic geophones in the borehole provides a higher resolution and more accurate image near the borehole, as well as other advantages relating to the unique position of the sensors relative to complex structures. Technical objectives are to complement surface seismic with improved resolution (~2X seismic), better high dip structure definition (e.g. salt flanks) and to fill in "imaging holes" in complex sub-salt plays where surface seismic is blind. Business drivers for this effort are to reduce risk in well placement, improved reserve calculation and understanding compartmentalization and stratigraphic variation. To date, BP has acquired 3D VSP surveys in ten wells in the DW GOM. The initial results are encouraging and show both improved resolution and structural images in complex sub-salt plays where the surface seismic is blind. In conjunction with this effort BP has influenced both contractor borehole seismic tool design and developed methods to enable the 3D VSP surveys to be conducted offline thereby avoiding the high daily rig costs associated with a Deepwater drilling rig.

  2. 3D image of Brittle/Ductile transition in active volcanic area and its implication on seismicity: The Campi Flegrei caldera case study

    NASA Astrophysics Data System (ADS)

    Castaldo, Raffaele; Luca, D'auria; Susi, Pepe; Giuseppe, Solaro; Pietro, Tizzani

    2015-04-01

    determine the rheological stratification of the crust beneath caldera. The best-fit model suggested that the uprising of a ductile layer, which connects the upper mantle to the volcanic feeding system, could have determined the stress condition that controls the distribution and magnitude of seismicity. Indeed, the computed 3D imaging of Brittle/Ductile transition agreed well with the distribution of earthquake hypocenters in the considered area. The location of the Benioff strain release, of the energy and of the number of earthquakes point out clearly that most of the seismicity occurs above 3500-4000 [m] depth, where the transition zone is individuated. Finally, our analysis revealed that the distribution of the Brittle/Ductile transition has also important implication in constraining the potential seismogenic volume. The inferred depth of 4000 [m] (for ɛ= 10-8 [s-1]), implies that a fault spanning the whole caldera (about 8000 [m]) with a stress drop of 4 [bar] would result in an event with magnitude 5.1. However, because of its highly fractured structure, such a long seismic rupture is unrealistic for CF caldera, at least in pre-eruptive conditions. In this scenario, a more realistic fault sizes (i.e. 4000x4000 [m2]) suggest as magnitude of pre-eruptive earthquakes at CF caldera lower than 5.

  3. DMO processing on the Ketzin 3D seismic data

    NASA Astrophysics Data System (ADS)

    Huang, Fei; Juhlin, Christopher; Ivandic, Monika; Zhang, Fengjiao

    2014-05-01

    The Dip-moveout (DMO) correction is a process which attempts to make the finite offset data closer to zero offset data after the normal-moveout (NMO) correction. The NMO correction is then dip independent and reflections with different dips will stack coherently. DMO plays a critical role in seismic processing by enhancing the final image quality of the seismic data. In this study, we apply 3D Squeezing DMO (Hale and Artley, 1993) to seismic data from the Ketzin pilot CO2 site after NMO to study the impact of DMO on time-lapse seismic imaging and to investigate if it enhances the CO2 seismic monitoring technique. This 3D DMO method is based on an integral approach and incorporates Hale and Artley's (1993) modifications for variable velocity with time. A constant velocity algorithm is used with a gamma correction function which depends on the velocity function. An anti-alias velocity of 3000 m/s is used for the DMO. After DMO the data are stacked and F-XY deconvolution is applied. Finally, 3D finite-difference migration using the final smoothed NMO velocities is performed for each data set. We then apply a time-lapse analysis to the 3D seismic data sets and compare the results with and without DMO processing. The most important aspect of the DMO processing is determining the velocity field for the NMO step. This is done by using the initial smoothed velocity field obtained from the conventional velocity analysis before DMO as a first estimate. The data are input into the DMO process and then inverse NMO is applied. These data are then subjected to a new velocity analysis and the velocity field is updated and used as input for the NMO process. A number of iterations are generally required until the velocity field does not need further updating. In this study velocities were picked at every 20th CDP in the inline and crossline directions. Compared to the velocity spectrum without DMO processing, the velocity trend is improved and the ambiguity in the velocity picks is

  4. Northern California Seismic Attenuation: 3-D Qp and Qs models

    NASA Astrophysics Data System (ADS)

    Eberhart-Phillips, D. M.

    2015-12-01

    The northern California crust exhibits a wide range of rock types and deformation processes which produce pronounced heterogeneity in regional attenuation. Using local earthquakes, 3-D Qp and Qs crustal models have been obtained for this region which includes the San Andreas fault system, the Central Valley, the Sierra Nevada batholith, and the Mendocino subduction volcanic system. Path attenuation t* values were determined from P and S spectra of 959 spatially distributed earthquakes, magnitude 2.5-6.0 from 2005-2014, using 1254 stations from NCEDC networks and IRIS Mendocino and Sierra Nevada temporary arrays. The t* data were used in Q inversions, using existing hypocenters and 3-D velocity models, with basic 10-km node spacing. The uneven data coverage was accounted for with linking of nodes into larger areas in order to provide useful Q images across the 3-D volume. The results at shallow depth (< 2 km) show very low Q in the Sacramento Delta, the Eureka area, and parts of the Bay Area. In the brittle crust, fault zones that have high seismicity exhibit low Q. In the lower crust, low Q is observed along fault zones that have large cumulative displacement and have experienced grain size reduction. Underlying active volcanic areas, low Q features are apparent below 20-km depth. Moderately high Q is associated with igneous rocks of the Sierra Nevada and Salinian block, while the Franciscan subduction complex shows moderately low Q. The most prominent high Q feature is related to the Great Valley Ophiolite.

  5. Computational 3-D inversion for seismic exploration

    SciTech Connect

    Gavrilov, E.M.; Forslund, D.W.; Fehler, M.C.

    1997-10-01

    This is the final report of a four-month, Laboratory Directed Research and Development (LDRD) project carried out at the Los Alamos National Laboratory (LANL). There is a great need for a new and effective technology with a wide scope of industrial applications to investigate media internal properties of which can be explored only from the backscattered data. The project was dedicated to the development of a three-dimensional computational inversion tool for seismic exploration. The new computational concept of the inversion algorithm was suggested. The goal of the project was to prove the concept and the practical validity of the algorithm for petroleum exploration.

  6. Accuracy in Quantitative 3D Image Analysis

    PubMed Central

    Bassel, George W.

    2015-01-01

    Quantitative 3D imaging is becoming an increasingly popular and powerful approach to investigate plant growth and development. With the increased use of 3D image analysis, standards to ensure the accuracy and reproducibility of these data are required. This commentary highlights how image acquisition and postprocessing can introduce artifacts into 3D image data and proposes steps to increase both the accuracy and reproducibility of these analyses. It is intended to aid researchers entering the field of 3D image processing of plant cells and tissues and to help general readers in understanding and evaluating such data. PMID:25804539

  7. Imaging Magma Under St. Helens (iMUSH): Details of passive-source seismic deployment and preliminary 3-D velocity structure

    NASA Astrophysics Data System (ADS)

    Ulberg, C. W.; Creager, K. C.; Moran, S. C.; Abers, G. A.; Denlinger, R. P.; Hotovec-Ellis, A. J.; Vidale, J. E.; Kiser, E.; Levander, A.; Schultz, A.

    2014-12-01

    The imaging Magma Under St. Helens (iMUSH) experiment aims to delineate the extent of the magmatic system beneath Mount St. Helens (MSH) in Washington State. The experiment involves active- and passive-source seismology, magnetotellurics, and geochemistry/petrology. Seventy passive-source broadband seismometers were deployed in a 100-km-diameter array centered on MSH, with an average spacing of 10 km, and a planned duration of two years. The deployment over two weeks in June 2014 involved a group of 18 people split into 6 teams. Approximately half of the seismic stations have aircell batteries and/or pole-mounted solar panels in order to maintain power through deep snow at higher elevations during the winter months. Data will be retrieved 2-4 times a year throughout the duration of the experiment. The first service run performed in mid-July 2014 had a 98.4% data recovery. This is one of the largest wide-aperture two-dimensional arrays covering a volcano anywhere. The active-source portion of the experiment successfully set off 23 shots in late-July 2014. These were recorded clearly at permanent stations run by the Pacific Northwest Seismic Network up to 200 km away, and are expected to be well-recorded on many of the 70 broadband seismometers in addition to the 2500 Reftek "Texans" deployed temporarily for this purpose. For the 2-4 weeks of broadband data collected in July, local earthquakes down to magnitude 0 are recorded across the array, with clear P- and S- arrivals. Earthquakes of this size occur daily within 50 km of MSH. We are keeping a careful catalog of all activity in the region for the duration of the iMUSH experiment. We will pick P- and S-wave travel times at the 70 broadband stations from local earthquakes and active shots, for available data from between June and October 2014. We will also use a tomographic code (Preston et al, 2003, Science) to invert the travel times to obtain preliminary earthquake location and 3-D velocity structure.

  8. 3D ultrafast ultrasound imaging in vivo

    NASA Astrophysics Data System (ADS)

    Provost, Jean; Papadacci, Clement; Esteban Arango, Juan; Imbault, Marion; Fink, Mathias; Gennisson, Jean-Luc; Tanter, Mickael; Pernot, Mathieu

    2014-10-01

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in 3D based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32  ×  32 matrix-array probe. Its ability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3D Shear-Wave Imaging, 3D Ultrafast Doppler Imaging, and, finally, 3D Ultrafast combined Tissue and Flow Doppler Imaging. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3D Ultrafast Doppler was used to obtain 3D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, at thousands of volumes per second, the complex 3D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, as well as the 3D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3D Ultrafast Ultrasound Imaging for the 3D mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra—and inter-observer variability.

  9. System and method for generating 3D images of non-linear properties of rock formation using surface seismic or surface to borehole seismic or both

    DOEpatents

    Vu, Cung Khac; Nihei, Kurt Toshimi; Johnson, Paul A.; Guyer, Robert A.; Ten Cate, James A.; Le Bas, Pierre-Yves; Larmat, Carene S.

    2016-06-07

    A system and method of characterizing properties of a medium from a non-linear interaction are include generating, by first and second acoustic sources disposed on a surface of the medium on a first line, first and second acoustic waves. The first and second acoustic sources are controllable such that trajectories of the first and second acoustic waves intersect in a mixing zone within the medium. The method further includes receiving, by a receiver positioned in a plane containing the first and second acoustic sources, a third acoustic wave generated by a non-linear mixing process from the first and second acoustic waves in the mixing zone; and creating a first two-dimensional image of non-linear properties or a first ratio of compressional velocity and shear velocity, or both, of the medium in a first plane generally perpendicular to the surface and containing the first line, based on the received third acoustic wave.

  10. 3D Ultrafast Ultrasound Imaging In Vivo

    PubMed Central

    Provost, Jean; Papadacci, Clement; Arango, Juan Esteban; Imbault, Marion; Gennisson, Jean-Luc; Tanter, Mickael; Pernot, Mathieu

    2014-01-01

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative real-time imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in three dimensions based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32×32 matrix-array probe. Its capability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3-D Shear-Wave Imaging, 3-D Ultrafast Doppler Imaging and finally 3D Ultrafast combined Tissue and Flow Doppler. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3-D Ultrafast Doppler was used to obtain 3-D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, for the first time, the complex 3-D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, and the 3-D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3-D Ultrafast Ultrasound Imaging for the 3-D real-time mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra- and inter-observer variability. PMID:25207828

  11. Additional geological insight brought by 3-D seismic data

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Milton, J.

    2002-12-01

    3-D seismic data allows geo-scientists to study the earth at a level that is much more detailed than ever. It is shown in this case study that 3-D seismic can not only be used to identify different types of oil/gas reservoirs, significantly reduce the risk of misinterpretation, but also help to understand geological history and establish paleogeography at different geological times. In the study of Southeast Maricopa Seismic Survey in southern San Joaquin Valley, two types of potential hydrocarbon traps are interpreted: stratigraphical traps due to turbidite channels, and structural traps due to faulting. The distinctive characteristics of two types of channels indicate different depositional environments. With 3-D visualization tools, it is found that localized faults had been leaking during certain geological times, resulting in structural traps of oil/gas. A geological history of the local area can be estimated by building a series of pseudo-paleogeographic maps using 3-D seismic data, which further reconfirms the existence of different depositional systems indicated by two distinctive types of channels.

  12. 3-D seismic exploration in the Ames hole

    SciTech Connect

    Ainsworth, K.R.

    1995-09-01

    The Ames Crater of Major County, Oklahoma has been one of the more controversial drilling projects to emerge in the Mid-Continent province in this decade. Within the crater, dolomitic and granodiorite breccias produce substantial quantities of oil and gas within structurally controlled accumulations. To understand the structural complexities of the crater, Continental Resources, in partnership with other Ames operators, acquired 3-D seismic data in four separate acquisition projects across various exploratory and development projects across the crater. Integrated seismic and subsurface control revealed four separate features within the principal crater floor oil and gas accumulation. Using the 3-D data as a lead tool, these companies identified and developed a significant number of commercial tests within the limits of the seismic surveys. Although the tool generally proved to be successful, reservoir variability, velocity variations, and interpretational errors resulted in some non-commercial and dry tests.

  13. Evaluation of 3D imaging.

    PubMed

    Vannier, M W

    2000-10-01

    Interactive computer-based simulation is gaining acceptance for craniofacial surgical planning. Subjective visualization without objective measurement capability, however, severely limits the value of simulation since spatial accuracy must be maintained. This study investigated the error sources involved in one method of surgical simulation evaluation. Linear and angular measurement errors were found to be within +/- 1 mm and 1 degree. Surface match of scanned objects was slightly less accurate, with errors up to 3 voxels and 4 degrees, and Boolean subtraction methods were 93 to 99% accurate. Once validated, these testing methods were applied to objectively compare craniofacial surgical simulations to post-operative outcomes, and verified that the form of simulation used in this study yields accurate depictions of surgical outcome. However, to fully evaluate surgical simulation, future work is still required to test the new methods in sufficient numbers of patients to achieve statistically significant results. Once completely validated, simulation cannot only be used in pre-operative surgical planning, but also as a post-operative descriptor of surgical and traumatic physical changes. Validated image comparison methods can also show discrepancy of surgical outcome to surgical plan, thus allowing evaluation of surgical technique. PMID:11098409

  14. Targeted infill drilling at Stratton field using 3-D seismic

    SciTech Connect

    Suydam, J.R.; Reitz, D.T.

    1994-12-31

    Stratton field is located on the Vicksburg flexure trend in Nueces and Kleberg Counties, South Texas. It has produced more than 2.8 Tcf of gas since 1937 from Frio fluvial/deltaic sandstones and Vicksburg shallow-marine sandstones. The field is a combination stratigraphic and faulted structural trap, and contains numerous highly compartmentalized sandstone reservoirs. Continuous infield drilling is required to keep the field producing, and 3-D seismic data have been used to select the best locations for these wells. In 1992, an 8-mi{sup 2} seismic survey was completed in the southern end of the field, and the resulting structural interpretation presented many more fault traps than were apparent in the 2-D seismic interpretation. So far, all of the new wells drilled within the survey have encountered untapped compartments enclosed by fault traps. Furthermore, fault cuts in the new wells have always been within 20 ft of the position predicted by seismic data.

  15. 3D seismic reverse time migration on GPGPU

    NASA Astrophysics Data System (ADS)

    Liu, Guofeng; Liu, Yaning; Ren, Li; Meng, Xiaohong

    2013-09-01

    Reverse time migration (RTM) is a powerful seismic imaging method for the interpretation of steep-dips and subsalt regions; however, implementation of the RTM method is computationally expensive. In this paper, we present a fast and computationally inexpensive implementation of RTM using a NVIDIA general purpose graphic processing unit (GPGPU) powered with Compute Unified Device Architecture (CUDA). To accomplish this, we introduced a random velocity boundary in the source propagation kernel. By creating a random velocity layer at the left, right, and bottom boundaries, the wave fields that encounter the boundary regions are pseudo-randomized. Reflections off the random layers have minimal coherent correlation in the reverse direction. This process eliminates the need to write the wave fields to a disk, which is important when using a GPU because of the limited bandwidth of the PCI-E that is connected to the CPU and GPU. There are four GPU kernels in the code: shot, receiver, modeling, and imaging. The shot and receiver insertion kernels are simple and are computed using a GPU because the wave fields reside in GPU's memory. The modeling kernel is computed using Micikevicius's tiling method, which uses shared memory to improve bandwidth usage in 2D and 3D finite difference problems. In the imaging kernel, we also use this tiling method. A Tesla C2050 GPU with 4 GB memory and 480 stream processing units was used to test the code. The shot and receiver modeling kernel occupancy achieved 85%, and the imaging kernel occupancy was 100%. This means that the code achieved a good level of optimization. A salt model test verified the correct and effective implementation of the GPU RTM code.

  16. 3D holoscopic video imaging system

    NASA Astrophysics Data System (ADS)

    Steurer, Johannes H.; Pesch, Matthias; Hahne, Christopher

    2012-03-01

    Since many years, integral imaging has been discussed as a technique to overcome the limitations of standard still photography imaging systems where a three-dimensional scene is irrevocably projected onto two dimensions. With the success of 3D stereoscopic movies, a huge interest in capturing three-dimensional motion picture scenes has been generated. In this paper, we present a test bench integral imaging camera system aiming to tailor the methods of light field imaging towards capturing integral 3D motion picture content. We estimate the hardware requirements needed to generate high quality 3D holoscopic images and show a prototype camera setup that allows us to study these requirements using existing technology. The necessary steps that are involved in the calibration of the system as well as the technique of generating human readable holoscopic images from the recorded data are discussed.

  17. Nonlaser-based 3D surface imaging

    SciTech Connect

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J.

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  18. Advanced computational tools for 3-D seismic analysis

    SciTech Connect

    Barhen, J.; Glover, C.W.; Protopopescu, V.A.

    1996-06-01

    The global objective of this effort is to develop advanced computational tools for 3-D seismic analysis, and test the products using a model dataset developed under the joint aegis of the United States` Society of Exploration Geophysicists (SEG) and the European Association of Exploration Geophysicists (EAEG). The goal is to enhance the value to the oil industry of the SEG/EAEG modeling project, carried out with US Department of Energy (DOE) funding in FY` 93-95. The primary objective of the ORNL Center for Engineering Systems Advanced Research (CESAR) is to spearhead the computational innovations techniques that would enable a revolutionary advance in 3-D seismic analysis. The CESAR effort is carried out in collaboration with world-class domain experts from leading universities, and in close coordination with other national laboratories and oil industry partners.

  19. NORTH HILL CREEK 3-D SEISMIC EXPLORATION PROJECT

    SciTech Connect

    Marc T. Eckels; David H. Suek; Denise H. Harrison; Paul J. Harrison

    2004-05-06

    Wind River Resources Corporation (WRRC) received a DOE grant in support of its proposal to acquire, process and interpret fifteen square miles of high-quality 3-D seismic data on non-allotted trust lands of the Uintah and Ouray (Ute) Indian Reservation, northeastern Utah, in 2000. Subsequent to receiving notice that its proposal would be funded, WRRC was able to add ten square miles of adjacent state and federal mineral acreage underlying tribal surface lands by arrangement with the operator of the Flat Rock Field. The twenty-five square mile 3-D seismic survey was conducted during the fall of 2000. The data were processed through the winter of 2000-2001, and initial interpretation took place during the spring of 2001. The initial interpretation identified multiple attractive drilling prospects, two of which were staked and permitted during the summer of 2001. The two initial wells were drilled in September and October of 2001. A deeper test was drilled in June of 2002. Subsequently a ten-well deep drilling evaluation program was conducted from October of 2002 through March 2004. The present report discusses the background of the project; design and execution of the 3-D seismic survey; processing and interpretation of the data; and drilling, completion and production results of a sample of the wells drilled on the basis of the interpreted survey. Fifteen wells have been drilled to test targets identified on the North Hill Creek 3-D Seismic Survey. None of these wildcat exploratory wells has been a dry hole, and several are among the best gas producers in Utah. The quality of the data produced by this first significant exploratory 3-D survey in the Uinta Basin has encouraged other operators to employ this technology. At least two additional 3-D seismic surveys have been completed in the vicinity of the North Hill Creek Survey, and five additional surveys are being planned for the 2004 field season. This project was successful in finding commercial oil, natural gas

  20. 3D Seismic Reflection Experiment over the Galicia Deep Basin

    NASA Astrophysics Data System (ADS)

    Sawyer, D. S.; Jordan, B.; Reston, T. J.; Minshull, T. A.; Klaeschen, D.; Ranero, C.; Shillington, D. J.; Morgan, J. K.

    2014-12-01

    In June thru September, 2013, a 3D reflection and a long offset seismic experiment were conducted at the Galicia rifted margin by investigators from the US, UK, Germany, and Spain. The 3D multichannel experiment covered 64 km by 20 km (1280 km2), using the RV Marcus Langseth. Four streamers 6 km long were deployed at 12.5 m hydrophone channel spacing. The streamers were 200 m apart. Two airgun arrays, each 3300 cu in, were fired alternately every 37.5 m, to collectively yield a 400 m wide sail line consisting of 8 CMP lines at 50 m spacing. The long offset seismic experiment included 72 short period OBS's deployed below the 3D reflection survey box. Most of the instruments recorded all the shots from the airgun array shots. The 3D seismic box covered a variety of geologic features. The Peridotite Ridge (PR), is associated with the exhumation of upper mantle rocks to the seafloor during the final stage of the continental separation between the Galicia Bank and the Grand Banks of Newfoundland. The S reflector is present below most of the continental blocks under the deep Galicia basin. S is interpreted to be a low-angle detachment fault formed late in the rifting process, and a number of rotated fault block basins and ranges containing pre and syn-rift sediments. Initial observations from stacked 3D seismic data, and samples of 2D pre-stack time migrated (PSTM) 3D seismic data show that the PR is elevated above the present seafloor in the South and not exposed through the seafloor in the North. The relative smoothness of the PR surface for the entire 20 km N-S contrasts with the more complex, shorter wavelength, faulting of the continental crustal blocks to the east. The PR does not seem to show offsets or any apparent internal structure. The PSTM dip lines show substantial improvement for the structures in the deep sedimentary basin East of the PR. These seem to extend the S reflector somewhat farther to the West. The migrated data show a substantial network of

  1. Miniaturized 3D microscope imaging system

    NASA Astrophysics Data System (ADS)

    Lan, Yung-Sung; Chang, Chir-Weei; Sung, Hsin-Yueh; Wang, Yen-Chang; Chang, Cheng-Yi

    2015-05-01

    We designed and assembled a portable 3-D miniature microscopic image system with the size of 35x35x105 mm3 . By integrating a microlens array (MLA) into the optical train of a handheld microscope, the biological specimen's image will be captured for ease of use in a single shot. With the light field raw data and program, the focal plane can be changed digitally and the 3-D image can be reconstructed after the image was taken. To localize an object in a 3-D volume, an automated data analysis algorithm to precisely distinguish profundity position is needed. The ability to create focal stacks from a single image allows moving or specimens to be recorded. Applying light field microscope algorithm to these focal stacks, a set of cross sections will be produced, which can be visualized using 3-D rendering. Furthermore, we have developed a series of design rules in order to enhance the pixel using efficiency and reduce the crosstalk between each microlens for obtain good image quality. In this paper, we demonstrate a handheld light field microscope (HLFM) to distinguish two different color fluorescence particles separated by a cover glass in a 600um range, show its focal stacks, and 3-D position.

  2. Structured light field 3D imaging.

    PubMed

    Cai, Zewei; Liu, Xiaoli; Peng, Xiang; Yin, Yongkai; Li, Ameng; Wu, Jiachen; Gao, Bruce Z

    2016-09-01

    In this paper, we propose a method by means of light field imaging under structured illumination to deal with high dynamic range 3D imaging. Fringe patterns are projected onto a scene and modulated by the scene depth then a structured light field is detected using light field recording devices. The structured light field contains information about ray direction and phase-encoded depth, via which the scene depth can be estimated from different directions. The multidirectional depth estimation can achieve high dynamic 3D imaging effectively. We analyzed and derived the phase-depth mapping in the structured light field and then proposed a flexible ray-based calibration approach to determine the independent mapping coefficients for each ray. Experimental results demonstrated the validity of the proposed method to perform high-quality 3D imaging for highly and lowly reflective surfaces. PMID:27607639

  3. 3D EIT image reconstruction with GREIT.

    PubMed

    Grychtol, Bartłomiej; Müller, Beat; Adler, Andy

    2016-06-01

    Most applications of thoracic EIT use a single plane of electrodes on the chest from which a transverse image 'slice' is calculated. However, interpretation of EIT images is made difficult by the large region above and below the electrode plane to which EIT is sensitive. Volumetric EIT images using two (or more) electrode planes should help compensate, but are little used currently. The Graz consensus reconstruction algorithm for EIT (GREIT) has become popular in lung EIT. One shortcoming of the original formulation of GREIT is its restriction to reconstruction onto a 2D planar image. We present an extension of the GREIT algorithm to 3D and develop open-source tools to evaluate its performance as a function of the choice of stimulation and measurement pattern. Results show 3D GREIT using two electrode layers has significantly more uniform sensitivity profiles through the chest region. Overall, the advantages of 3D EIT are compelling. PMID:27203184

  4. Targeted infill drilling at Stratton Field using 3-D seismic

    SciTech Connect

    Suydam, J.; Reitz, D.

    1994-09-01

    Stratton field is located on the Vicksburg flexure trend in Nueces and Kleberg counties, south Texas. It has produced over 2.8 tcf of gas since 1937 from Frio fluvial/deltaic sandstones and Vicksburg shallow marine sandstones. The field is a combination stratigraphic and faulted structural trap, and contains numerous highly compartmentalized sandstone reservoirs. Continuous infield drilling is required to keep the field producing, and 3-D seismic data have been used to select the best locations for these wells. In 1992, the Bureau of Economic Geology shot an 8-mi{sup 2} survey in the southern end of the field, and the resulting structural interpretation presented many more fault traps that were not apparent in the 2-D seismic interpretation. So far, all of the new wells drilled within the survey have encountered untapped compartments enclosed by fault traps. Furthermore, fault cuts in the new wells have always been within 20 ft of the position predicted by seismic data.

  5. ICER-3D Hyperspectral Image Compression Software

    NASA Technical Reports Server (NTRS)

    Xie, Hua; Kiely, Aaron; Klimesh, matthew; Aranki, Nazeeh

    2010-01-01

    Software has been developed to implement the ICER-3D algorithm. ICER-3D effects progressive, three-dimensional (3D), wavelet-based compression of hyperspectral images. If a compressed data stream is truncated, the progressive nature of the algorithm enables reconstruction of hyperspectral data at fidelity commensurate with the given data volume. The ICER-3D software is capable of providing either lossless or lossy compression, and incorporates an error-containment scheme to limit the effects of data loss during transmission. The compression algorithm, which was derived from the ICER image compression algorithm, includes wavelet-transform, context-modeling, and entropy coding subalgorithms. The 3D wavelet decomposition structure used by ICER-3D exploits correlations in all three dimensions of sets of hyperspectral image data, while facilitating elimination of spectral ringing artifacts, using a technique summarized in "Improving 3D Wavelet-Based Compression of Spectral Images" (NPO-41381), NASA Tech Briefs, Vol. 33, No. 3 (March 2009), page 7a. Correlation is further exploited by a context-modeling subalgorithm, which exploits spectral dependencies in the wavelet-transformed hyperspectral data, using an algorithm that is summarized in "Context Modeler for Wavelet Compression of Hyperspectral Images" (NPO-43239), which follows this article. An important feature of ICER-3D is a scheme for limiting the adverse effects of loss of data during transmission. In this scheme, as in the similar scheme used by ICER, the spatial-frequency domain is partitioned into rectangular error-containment regions. In ICER-3D, the partitions extend through all the wavelength bands. The data in each partition are compressed independently of those in the other partitions, so that loss or corruption of data from any partition does not affect the other partitions. Furthermore, because compression is progressive within each partition, when data are lost, any data from that partition received

  6. Acquisition and applications of 3D images

    NASA Astrophysics Data System (ADS)

    Sterian, Paul; Mocanu, Elena

    2007-08-01

    The moiré fringes method and their analysis up to medical and entertainment applications are discussed in this paper. We describe the procedure of capturing 3D images with an Inspeck Camera that is a real-time 3D shape acquisition system based on structured light techniques. The method is a high-resolution one. After processing the images, using computer, we can use the data for creating laser fashionable objects by engraving them with a Q-switched Nd:YAG. In medical field we mention the plastic surgery and the replacement of X-Ray especially in pediatric use.

  7. 3D camera tracking from disparity images

    NASA Astrophysics Data System (ADS)

    Kim, Kiyoung; Woo, Woontack

    2005-07-01

    In this paper, we propose a robust camera tracking method that uses disparity images computed from known parameters of 3D camera and multiple epipolar constraints. We assume that baselines between lenses in 3D camera and intrinsic parameters are known. The proposed method reduces camera motion uncertainty encountered during camera tracking. Specifically, we first obtain corresponding feature points between initial lenses using normalized correlation method. In conjunction with matching features, we get disparity images. When the camera moves, the corresponding feature points, obtained from each lens of 3D camera, are robustly tracked via Kanade-Lukas-Tomasi (KLT) tracking algorithm. Secondly, relative pose parameters of each lens are calculated via Essential matrices. Essential matrices are computed from Fundamental matrix calculated using normalized 8-point algorithm with RANSAC scheme. Then, we determine scale factor of translation matrix by d-motion. This is required because the camera motion obtained from Essential matrix is up to scale. Finally, we optimize camera motion using multiple epipolar constraints between lenses and d-motion constraints computed from disparity images. The proposed method can be widely adopted in Augmented Reality (AR) applications, 3D reconstruction using 3D camera, and fine surveillance systems which not only need depth information, but also camera motion parameters in real-time.

  8. 3D Seismic Reflection Experiment Over the Galicia Deep Basin

    NASA Astrophysics Data System (ADS)

    Sawyer, Dale; Jordan, Brian; Tesi Sanjurjo, Mari; Alexanian, Ara; Morgan, Julia; Shillington, Donna; Reston, Timothy; Minshull, Timothy; Klaeschen, Dirk; Ranero, César

    2014-05-01

    In June thru September, 2013, a 3D reflection and a long offset seismic experiment were conducted at the Galicia rifted margin by investigators from the US, UK, Germany, and Spain. The 3D multichannel experiment covered 64 km by 20 km (1280 km2), using the RV Marcus Langseth. Four streamers 6 km long were deployed at 12.5 m hydrophone channel spacing. The streamers were 200 m apart. Two airgun arrays, each 3300 cu in, were fired alternately every 37.5 m, to collectively yield a 400 m wide sail line consisting of 8 CMP lines at 50 m spacing. The long offset seismic experiment included 72 short period OBS's deployed below the 3D reflection survey box. Most of the instruments recorded all the shots from the airgun array shots. The 3D seismic box covered a variety of geologic features. The Peridotite Ridge (PR), is associated with the exhumation of upper mantle rocks to the seafloor during the final stage of the continental separation between the Galicia Bank and the Grand Banks of Newfoundland. The S reflector is present below most of the continental blocks under the deep Galicia basin. S is interpreted to be a low-angle detachment fault formed late in the rifting process, and a number of rotated fault block basins and ranges containing pre and syn-rift sediments. Initial observations from stacked, but not yet migrated, 3D seismic data show that the PR is elevated above the present seafloor in the South and not exposed through the seafloor in the North. The relative smoothness of the PR surface for the entire 20 km N-S contrasts with the more complex, shorter wavelength, faulting of the continental crustal blocks to the east. The PR does not seem to show offsets or any apparent internal structure. However, migration will be required to see internal structure of the PR. Between the PR and the western most rifted continental crustal blocks, is a sedimentary basin about as wide as the PR and very different from the sedimentary basins bounded by the continental crustal

  9. High definition 3D ultrasound imaging.

    PubMed

    Morimoto, A K; Krumm, J C; Kozlowski, D M; Kuhlmann, J L; Wilson, C; Little, C; Dickey, F M; Kwok, K S; Rogers, B; Walsh, N

    1997-01-01

    We have demonstrated high definition and improved resolution using a novel scanning system integrated with a commercial ultrasound machine. The result is a volumetric 3D ultrasound data set that can be visualized using standard techniques. Unlike other 3D ultrasound images, image quality is improved from standard 2D data. Image definition and bandwidth is improved using patent pending techniques. The system can be used to image patients or wounded soldiers for general imaging of anatomy such as abdominal organs, extremities, and the neck. Although the risks associated with x-ray carcinogenesis are relatively low at diagnostic dose levels, concerns remain for individuals in high risk categories. In addition, cost and portability of CT and MRI machines can be prohibitive. In comparison, ultrasound can provide portable, low-cost, non-ionizing imaging. Previous clinical trials comparing ultrasound to CT were used to demonstrate qualitative and quantitative improvements of ultrasound using the Sandia technologies. Transverse leg images demonstrated much higher clarity and lower noise than is seen in traditional ultrasound images. An x-ray CT scan was provided of the same cross-section for comparison. The results of our most recent trials demonstrate the advantages of 3D ultrasound and motion compensation compared with 2D ultrasound. Metal objects can also be observed within the anatomy. PMID:10168958

  10. 3D seismics for geothermal reservoir characterization - a case study from Schneeberg (Germany)

    NASA Astrophysics Data System (ADS)

    Hlousek, F.; Hellwig, O.; Buske, S.

    2013-12-01

    We present the results of a 3D seismic survey acquired near Schneeberg in the western Erzgebirge (Germany). The aim of the project is to use seismic exploration methods to image and to characterize a major fault zone in crystalline rock which could be used as a geothermal reservoir at a target depth of about 5-6 km with expected temperatures between 160-180°C. For this purpose a high resolution 3D Vibroseis survey with more than 5300 source and approximately 8000 receiver locations was performed at the end of 2012 and covered an area of approximately 10 km x 13 km. The 3D survey was complemented by an additional wide-angle seismic survey using explosives along eleven profile lines radially centered at the target area. The region itself is dominated by the NW-SE striking Gera-Jáchymov fault system. The main geological features in the survey area are well known from intensive mining activities down to a depth of about 2 km. The seismic investigations aimed at imaging the partly steeply dipping fault branches at greater depth, in particular a dominant steeply NE dipping fault in the central part of the survey area. Beside this main structure, the Gera-Jáchymov fault zone consists of a couple of steeply SW dipping conjugated faults. Advanced processing and imaging methods have been applied to the data set. 3D Kirchhoff prestack depth migration delivered a clear image of the structure of the various fault branches at depths of around 2-5 km. Furthermore, focusing migration methods (e.g. coherency migration) have been applied and even sharpened the image such that the 3D seismic result allows for a profound characterization of this potential geothermal reservoir in crystalline rock.

  11. Prestack reverse time migration for 3D marine reflection seismic data

    SciTech Connect

    Jang, Seonghyung; Kim, Taeyoun

    2015-03-10

    Prestack reverse time migration (RTM) is a method for imaging the subsurface using the inner product of wavefield extrapolation in shot domain and in receiver domain. It is well known that RTM is better for preserving amplitudes and phases than other prestack migrations. Since 3D seismic data is huge data volume and it needs heavy computing works, it requires parallel computing in order to have a meaningful depth image of the 3D subsurface. We implemented a parallelized version of 3D RTM for prestack depth migration. The results of numerical example for 3D SEG/EAGE salt model showed good agreement with the original geological model. We applied RTM to offshore 3D seismic reflection data. The study area is 12 × 25 km with 120 survey lines. Shot and receiver spacing is 25 m and 12.5 m. The line spacing is 100 m. Shot gathers were preprocessed to enhance signal to noise ratio and velocity model was calculated from conventional stack velocity. Both of them were used to obtain 3D image using RTM. The results show reasonable subsurface image.

  12. Exploration 3-D Seismic Field Test/Native Tribes Initiative

    SciTech Connect

    Carroll, Herbert B.; Chen, K.C.; Guo, Genliang; Johnson, W.I.; Reeves,T.K.; Sharma,Bijon

    1999-04-27

    To determine current acquisition procedures and costs and to further the goals of the President's Initiative for Native Tribes, a seismic-survey project is to be conducted on Osage tribal lands. The goals of the program are to demonstrate the capabilities, costs, and effectiveness of 3-D seismic work in a small-operator setting and to determine the economics of such a survey. For these purposes, typical small-scale independent-operator practices are being followed and a shallow target chose in an area with a high concentration of independent operators. The results will be analyzed in detail to determine if there are improvements and/or innovations which can be easily introduced in field-acquisition procedures, in processing, or in data manipulation and interpretation to further reduce operating costs and to make the system still more active to the small-scale operator.

  13. Widespread 3D seismic survey covers mature field in Gabon

    SciTech Connect

    Riley, D.; Fleming, M. ); Delvaux, J. )

    1993-12-06

    The exploration potential of the Port Gentil region, characterized by some of the earliest petroleum discoveries in Gabon, continues to be of important interest today. Available seismic data are of an older vintage (1974--82), recorded with low common mid-point (CMP) fold. They are critically void of coverage through the transition zone. The geology is highly complex, characterized by salt structures and strong tectonic activity. An intensive joint exploration and reservoir definition campaign is crucial to full evaluation of this area. This article describes the 3D survey conducted during 1992 and early 1993 over a mature oil field in an around Port Gentil and incorporating elements of land, transition zone, and shallow marine data acquisition -- the 3D Mandji program.

  14. Backhoe 3D "gold standard" image

    NASA Astrophysics Data System (ADS)

    Gorham, LeRoy; Naidu, Kiranmai D.; Majumder, Uttam; Minardi, Michael A.

    2005-05-01

    ViSUAl-D (VIsual Sar Using ALl Dimensions), a 2004 DARPA/IXO seedling effort, is developing a capability for reliable high confidence ID from standoff ranges. Recent conflicts have demonstrated that the warfighter would greatly benefit from the ability to ID targets beyond visual and electro-optical ranges[1]. Forming optical-quality SAR images while exploiting full polarization, wide angles, and large bandwidth would be key evidence such a capability is achievable. Using data generated by the Xpatch EM scattering code, ViSUAl-D investigates all degrees of freedom available to the radar designer, including 6 GHz bandwidth, full polarization and angle sampling over 2π steradians (upper hemisphere), in order to produce a "literal" image or representation of the target. This effort includes the generation of a "Gold Standard" image that can be produced at X-band utilizing all available target data. This "Gold Standard" image of the backhoe will serve as a test bed for future more relevant military targets and their image development. The seedling team produced a public release data which was released at the 2004 SPIE conference, as well as a 3D "Gold Standard" backhoe image using a 3D image formation algorithm. This paper describes the full backhoe data set, the image formation algorithm, the visualization process and the resulting image.

  15. Exploring the seismic expression of fault zones in 3D seismic volumes

    NASA Astrophysics Data System (ADS)

    Iacopini, D.; Butler, R. W. H.; Purves, S.; McArdle, N.; De Freslon, N.

    2016-08-01

    Mapping and understanding distributed deformation is a major challenge for the structural interpretation of seismic data. However, volumes of seismic signal disturbance with low signal/noise ratio are systematically observed within 3D seismic datasets around fault systems. These seismic disturbance zones (SDZ) are commonly characterized by complex perturbations of the signal and occur at the sub-seismic (10 s m) to seismic scale (100 s m). They may store important information on deformation distributed around those larger scale structures that may be readily interpreted in conventional amplitude displays of seismic data. We introduce a method to detect fault-related disturbance zones and to discriminate between this and other noise sources such as those associated with the seismic acquisition (footprint noise). Two case studies from the Taranaki basin and deep-water Niger delta are presented. These resolve SDZs using tensor and semblance attributes along with conventional seismic mapping. The tensor attribute is more efficient in tracking volumes containing structural displacements while structurally-oriented semblance coherency is commonly disturbed by small waveform variations around the fault throw. We propose a workflow to map and cross-plot seismic waveform signal properties extracted from the seismic disturbance zone as a tool to investigate the seismic signature and explore seismic facies of a SDZ.

  16. Exploring the seismic expression of fault zones in 3D seismic volumes

    NASA Astrophysics Data System (ADS)

    Iacopini, David; Butler, Rob; Purves, Steve

    2016-04-01

    Mapping and understanding distributed deformation is a major challenge for the structural interpretation of seismic data. However, volumes of seismic signal disturbance with low signal/noise ratio are systematically observed within 3D seismic datasets around fault systems. These seismic disturbance zones (SDZ) are commonly characterized by complex perturbations of the signal and occur at the sub-seismic to seismic scale. They may store important information on deformation distributed around those larger scale structures that may be readily interpreted in conventional amplitude displays of seismic data scale. We introduce a method to detect fault-related disturbance zones and to discriminate between this and other noise sources such as those associated with the seismic acquisition (footprint noise). Two case studies, from the Taranaki basin and deep-water Niger delta are presented. These resolve structure within SDZs using tensor and semblance attributes along with conventional seismic mapping. The tensor attribute is more efficient in tracking volumes containing structural displacements while structurally-oriented semblance coherency is commonly disturbed by small waveform variations around the fault throw. We propose a workflow to map and cross-plot seismic waveform signal properties extracted from the seismic disturbance zone as a tool to investigate the seismic signature and explore seismic facies of a SDZ.

  17. 3-D Autojuggie: Automating Deployment of Two-Dimensional Geophone Arrays for Efficient Ultra-Shallow Seismic-Reflection Surveys

    NASA Astrophysics Data System (ADS)

    Tsoflias, G. P.; Steeples, D. W.; Czarnecki, G.; Sloan, S. D.; Eslick, R.

    2005-12-01

    Near-surface seismic reflection methods require dense spatial sampling of the wavefield. Seismic surveys imaging the top ten meters of the subsurface employ geophone spacing on the order of decimeters. Two-dimensional (2-D), ultra-shallow seismic reflection methods have increased in popularity. However, placement of geophones remains a labor-intensive deterrent to the acquisition of near-surface, 3-D seismic data. Although 3-D seismic imaging is a mature hydrocarbon-exploration technique, only a handful of 3-D shallow seismic surveys have been acquired over the last decade. We present the development and field-testing of instrumentation for automatic deployment of a 2-D array of 72 geophones for acquisition of ultra-shallow 3-D reflection seismic data, referred to as the 3-D Autojuggie. The main components of the instrumentation include: a) two vertically stacked rigid steel frames used for positioning, planting, and transporting an array of geophones; b) an hydraulically controlled mechanism for decoupling the geophones from the steel frames during seismic data recording; and c) a 2-D array of seventy-two 100 Hz Mark Products geophones with 20.32 cm long spikes, spaced 20 cm apart in the inline (12 geophones) and crossline (6 rows) orientation. Seismic noise testing (walkaways) conducted at The University of Kansas employing automatically planted 2-D geophone arrays next to conventional hand-planted geophones resulted in equivalent seismic imaging of the subsurface. The geophone planting instrumentation did not degrade the quality of the recorded wavefield. The efficiency of automatically placing a dense 2-D array of geophones on the ground and the ease of moving the array quickly to adjacent positions, along with the ability to acquire comparable quality data to conventional hand-planted geophones, indicate that the 3-D Autojuggie is a viable approach to ultra-shallow 3-D seismic acquisition. Conceptually, the design could accommodate an array of hundreds of

  18. Metrological characterization of 3D imaging devices

    NASA Astrophysics Data System (ADS)

    Guidi, G.

    2013-04-01

    Manufacturers often express the performance of a 3D imaging device in various non-uniform ways for the lack of internationally recognized standard requirements for metrological parameters able to identify the capability of capturing a real scene. For this reason several national and international organizations in the last ten years have been developing protocols for verifying such performance. Ranging from VDI/VDE 2634, published by the Association of German Engineers and oriented to the world of mechanical 3D measurements (triangulation-based devices), to the ASTM technical committee E57, working also on laser systems based on direct range detection (TOF, Phase Shift, FM-CW, flash LADAR), this paper shows the state of the art about the characterization of active range devices, with special emphasis on measurement uncertainty, accuracy and resolution. Most of these protocols are based on special objects whose shape and size are certified with a known level of accuracy. By capturing the 3D shape of such objects with a range device, a comparison between the measured points and the theoretical shape they should represent is possible. The actual deviations can be directly analyzed or some derived parameters can be obtained (e.g. angles between planes, distances between barycenters of spheres rigidly connected, frequency domain parameters, etc.). This paper shows theoretical aspects and experimental results of some novel characterization methods applied to different categories of active 3D imaging devices based on both principles of triangulation and direct range detection.

  19. 3D MR imaging in real time

    NASA Astrophysics Data System (ADS)

    Guttman, Michael A.; McVeigh, Elliot R.

    2001-05-01

    A system has been developed to produce live 3D volume renderings from an MR scanner. Whereas real-time 2D MR imaging has been demonstrated by several groups, 3D volumes are currently rendered off-line to gain greater understanding of anatomical structures. For example, surgical planning is sometimes performed by viewing 2D images or 3D renderings from previously acquired image data. A disadvantage of this approach is misregistration which could occur if the anatomy changes due to normal muscle contractions or surgical manipulation. The ability to produce volume renderings in real-time and present them in the magnet room could eliminate this problem, and enable or benefit other types of interventional procedures. The system uses the data stream generated by a fast 2D multi- slice pulse sequence to update a volume rendering immediately after a new slice is available. We demonstrate some basic types of user interaction with the rendering during imaging at a rate of up to 20 frames per second.

  20. Frio, Yegua objectives of E. Texas 3D seismic

    SciTech Connect

    1996-07-01

    Houston companies plan to explore deeper formations along the Sabine River on the Texas and Louisiana Gulf Coast. PetroGuard Co. Inc. and Jebco Seismic Inc., Houston, jointly secured a seismic and leasing option from Hankamer family et al. on about 120 sq miles in Newton County, Tex., and Calcasieu Parish, La. PetroGuard, which specializes in oilfield rehabilitation, has production experience in the area. Historic production in the area spans three major geologic trends: Oligocene Frio/Hackberry, downdip and mid-dip Eocene Yegua, and Eocene Wilcox. In the southern part of the area, to be explored first, the trends lie at 9,000--10,000 ft, 10,000--12,000 ft, and 14,000--15,000 ft, respectively. Output Exploration Co., an affiliate of Input/Output Inc., Houston, acquired from PetroGuard and Jebco all exploratory drilling rights in the option area. Output will conduct 3D seismic operations over nearly half the acreage this summer. Data acquisition started late this spring. Output plans to use a combination of a traditional land recording system and I/O`s new RSR 24 bit radio telemetry system because the area spans environments from dry land to swamp.

  1. Areal 3-D seismic technique for reservoir delineation: Case history from offshore Niger Delta

    SciTech Connect

    Idowu, A.O. )

    1993-02-01

    In the 1950s, early exploration period in the Niger Delta witnessed the use of 2-D (two dimensional) seismic reflection method which adequate for imaging large subsurface geologic features including growth faulting and roll-over anticlines. This technique involves the Common-Depth-Point method (CDP) which acquires a plane of seismic information in distance along the surface and in time into the geological section, and is used to improve the signal-to-noise (S/N) ratio, to remove multiples and consequently give a representation of the subsurface particularly if the data are collected up- or downdip. By mid-1980s, the obvious geological structures have, in general, been discovered and it became necessary to adopt a more sophisticated technique such as the 3-D (three dimensional) seismic method to delineate more subtle reservoirs and resolve complex fault patterns in order to aid exploration as well as facilitate efficient field development. The case history discussed in this paper involves the use of areal 3-D seismic method for delineating the reservoir characterization of the O-field located in a shallow water area of the western Niger Delta. The areal 3-D seismic technique is superior to the earlier CDP method in that a cube of seismic data can be collected in two dimensions in space and one in time by a variety of techniques including the swath seismic shooting pattern adopted for gathering the 3-D data for the O-field's reservoir which involves the line of sources. The objective is to adequately sample the subsurface so that changes in various parameters such as the amplitude phase or power in the siesmic signal or velocity of propagation can be mapped areally and interpreted as an indication of changes in the physical properties of the rock matrix.

  2. Geomatics for precise 3D breast imaging.

    PubMed

    Alto, Hilary

    2005-02-01

    Canadian women have a one in nine chance of developing breast cancer during their lifetime. Mammography is the most common imaging technology used for breast cancer detection in its earliest stages through screening programs. Clusters of microcalcifications are primary indicators of breast cancer; the shape, size and number may be used to determine whether they are malignant or benign. However, overlapping images of calcifications on a mammogram hinder the classification of the shape and size of each calcification and a misdiagnosis may occur resulting in either an unnecessary biopsy being performed or a necessary biopsy not being performed. The introduction of 3D imaging techniques such as standard photogrammetry may increase the confidence of the radiologist when making his/her diagnosis. In this paper, traditional analytical photogrammetric techniques for the 3D mathematical reconstruction of microcalcifications are presented. The techniques are applied to a specially designed and constructed x-ray transparent Plexiglas phantom (control object). The phantom was embedded with 1.0 mm x-ray opaque lead pellets configured to represent overlapping microcalcifications. Control points on the phantom were determined by standard survey methods and hand measurements. X-ray films were obtained using a LORAD M-III mammography machine. The photogrammetric techniques of relative and absolute orientation were applied to the 2D mammographic films to analytically generate a 3D depth map with an overall accuracy of 0.6 mm. A Bundle Adjustment and the Direct Linear Transform were used to confirm the results. PMID:15649085

  3. P-Cable: New High-Resolution 3D Seismic Acquisition Technology

    NASA Astrophysics Data System (ADS)

    Planke, Sverre; Berndt, Christian; Mienert, Jürgen; Bünz, Stefan; Eriksen, Frode N.; Eriksen, Ola K.

    2010-05-01

    We have developed a new cost-efficient technology for acquisition of high-resolution 3D seismic data: the P-Cable system. This technology is very well suited for deep water exploration, site surveys, and studies of shallow gas and fluid migration associated with gas hydrates or leaking reservoirs. It delivers unparalleled 3D seismic images of subsurface sediment architectures. The P-Cable system consists of a seismic cable towed perpendicular to a vessel's steaming direction. This configuration allows us to image an up to 150 m wide swath of the sub-surface for each sail line. Conventional 3D seismic technology relies on several very long streamers (up to 10 km long streamers are common), large sources, and costly operations. In contrast, the P-Cable system is light-weight and fast to deploy from small vessels. Only a small source is required as the system is made for relatively shallow imaging, typically above the first water-bottom multiple. The P-Cable system is particularly useful for acquisition of small 3D cubes, 10-50 km2, in focus areas, rather than extensive mapping of large regions. The rapid deployment and recovery of the system makes it possible to acquire several small cubes (10 to 30 km2) with high-resolution (50-250 Hz) seismic data in during one cruise. The first development of the P-Cable system was a cooperative project achieved by Volcanic Basin Petroleum Research (VBPR), University of Tromsø, National Oceanography Centre, Southampton, and industry partners. Field trials using a 12-streamer system were conducted on sites with active fluid-leakage systems on the Norwegian-Barents-Svalbard margin, the Gulf of Cadiz, and the Mediterranean. The second phase of the development introduced digital streamers. The new P-Cable2 system also includes integrated tow and cross cables for power and data transmission and improved doors to spread the larger cross cable. This digital system has been successfully used during six cruises by the University of Troms

  4. Pattern based 3D image Steganography

    NASA Astrophysics Data System (ADS)

    Thiyagarajan, P.; Natarajan, V.; Aghila, G.; Prasanna Venkatesan, V.; Anitha, R.

    2013-03-01

    This paper proposes a new high capacity Steganographic scheme using 3D geometric models. The novel algorithm re-triangulates a part of a triangle mesh and embeds the secret information into newly added position of triangle meshes. Up to nine bits of secret data can be embedded into vertices of a triangle without causing any changes in the visual quality and the geometric properties of the cover image. Experimental results show that the proposed algorithm is secure, with high capacity and low distortion rate. Our algorithm also resists against uniform affine transformations such as cropping, rotation and scaling. Also, the performance of the method is compared with other existing 3D Steganography algorithms. [Figure not available: see fulltext.

  5. Teat Morphology Characterization With 3D Imaging.

    PubMed

    Vesterinen, Heidi M; Corfe, Ian J; Sinkkonen, Ville; Iivanainen, Antti; Jernvall, Jukka; Laakkonen, Juha

    2015-07-01

    The objective of this study was to visualize, in a novel way, the morphological characteristics of bovine teats to gain a better understanding of the detailed teat morphology. We applied silicone casting and 3D digital imaging in order to obtain a more detailed image of the teat structures than that seen in previous studies. Teat samples from 65 dairy cows over 12 months of age were obtained from cows slaughtered at an abattoir. The teats were classified according to the teat condition scoring used in Finland and the lengths of the teat canals were measured. Silicone molds were made from the external teat surface surrounding the teat orifice and from the internal surface of the teat consisting of the papillary duct, Fürstenberg's rosette, and distal part of the teat cistern. The external and internal surface molds of 35 cows were scanned with a 3D laser scanner. The molds and the digital 3D models were used to evaluate internal and external teat surface morphology. A number of measurements were taken from the silicone molds. The 3D models reproduced the morphology of the teats accurately with high repeatability. Breed didn't correlate with the teat classification score. The rosette was found to have significant variation in its size and number of mucosal folds. The internal surface morphology of the rosette did not correlate with the external surface morphology of the teat implying that it is relatively independent of milking parameters that may impact the teat canal and the external surface of the teat. PMID:25382725

  6. Integrating 3D seismic curvature and curvature gradient attributes for fracture characterization: Methodologies and interpretational implications

    SciTech Connect

    Gao, Dengliang

    2013-03-01

    In 3D seismic interpretation, curvature is a popular attribute that depicts the geometry of seismic reflectors and has been widely used to detect faults in the subsurface; however, it provides only part of the solutions to subsurface structure analysis. This study extends the curvature algorithm to a new curvature gradient algorithm, and integrates both algorithms for fracture detection using a 3D seismic test data set over Teapot Dome (Wyoming). In fractured reservoirs at Teapot Dome known to be formed by tectonic folding and faulting, curvature helps define the crestal portion of the reservoirs that is associated with strong seismic amplitude and high oil productivity. In contrast, curvature gradient helps better define the regional northwest-trending and the cross-regional northeast-trending lineaments that are associated with weak seismic amplitude and low oil productivity. In concert with previous reports from image logs, cores, and outcrops, the current study based on an integrated seismic curvature and curvature gradient analysis suggests that curvature might help define areas of enhanced potential to form tensile fractures, whereas curvature gradient might help define zones of enhanced potential to develop shear fractures. In certain fractured reservoirs such as at Teapot Dome where faulting and fault-related folding contribute dominantly to the formation and evolution of fractures, curvature and curvature gradient attributes can be potentially applied to differentiate fracture mode, to predict fracture intensity and orientation, to detect fracture volume and connectivity, and to model fracture networks.

  7. The USGS 3D Seismic Velocity Model for Northern California

    NASA Astrophysics Data System (ADS)

    Brocher, T. M.; Aagaard, B.; Simpson, R. W.; Jachens, R. C.

    2006-12-01

    We present a new regional 3D seismic velocity model for Northern California for use in strong motion simulations of the 1906 San Francisco and other earthquakes. The model includes compressional-wave velocity (Vp), shear-wave velocity (Vs), density, and intrinsic attenuation (Qp, Qs). These properties were assigned for each rock type in a 3D geologic model derived from surface outcrops, boreholes, gravity and magnetic data, and seismic reflection, refraction, and tomography studies. A detailed description of the model, USGS Bay Area Velocity Model 05.1.0, is available online [http://www.sf06simulation.org/geology/velocitymodel]. For ground motion simulations Vs and Qs are more important parameters than Vp and Qp because the strongest ground motions are generated chiefly by shear and surface wave arrivals. Because Vp data are more common than Vs data, however, we first developed Vp versus depth relations for each rock type and then converted these to Vs versus depth relations. For the most important rock types in Northern California we compiled measurements of Vp versus depth using borehole logs, laboratory measurements on hand samples, seismic refraction profiles, and tomography models. These rock types include Salinian and Sierran granitic rocks, metagraywackes and greenstones of the Franciscan Complex, Tertiary and Mesozoic sedimentary and volcanic rocks, and Quaternary and Holocene deposits (Brocher, USGS OFR 05-1317, 2005). Vp versus depth curves were converted to Vs versus depth curves using new empirical nonlinear relations between Vs and Vp (Brocher, BSSA, 2005). These relations, showing that Poisson's ratio is a nonlinear function of Vp, were similarly based on compilations of diverse Vs and Vp measurements on a large suite of rock types, mainly from California and the Pacific Northwest. The model is distributed in a discretized form with routines to query the model using C++, C, and Fortran 77 programming languages. The geologic model was discretized at

  8. 3D GPR Imaging of Wooden Logs

    NASA Astrophysics Data System (ADS)

    Halabe, Udaya B.; Pyakurel, Sandeep

    2007-03-01

    There has been a lack of an effective NDE technique to locate internal defects within wooden logs. The few available elastic wave propagation based techniques are limited to predicting E values. Other techniques such as X-rays have not been very successful in detecting internal defects in logs. If defects such as embedded metals could be identified before the sawing process, the saw mills could significantly increase their production by reducing the probability of damage to the saw blade and the associated downtime and the repair cost. Also, if the internal defects such as knots and decayed areas could be identified in logs, the sawing blade can be oriented to exclude the defective portion and optimize the volume of high valued lumber that can be obtained from the logs. In this research, GPR has been successfully used to locate internal defects (knots, decays and embedded metals) within the logs. This paper discusses GPR imaging and mapping of the internal defects using both 2D and 3D interpretation methodology. Metal pieces were inserted in a log and the reflection patterns from these metals were interpreted from the radargrams acquired using 900 MHz antenna. Also, GPR was able to accurately identify the location of knots and decays. Scans from several orientations of the log were collected to generate 3D cylindrical volume. The actual location of the defects showed good correlation with the interpreted defects in the 3D volume. The time/depth slices from 3D cylindrical volume data were useful in understanding the extent of defects inside the log.

  9. 3D finite-difference seismic migration with parallel computers

    SciTech Connect

    Ober, C.C.; Gjertsen, R.; Minkoff, S.; Womble, D.E.

    1998-11-01

    The ability to image complex geologies such as salt domes in the Gulf of Mexico and thrusts in mountainous regions is essential for reducing the risk associated with oil exploration. Imaging these structures, however, is computationally expensive as datasets can be terabytes in size. Traditional ray-tracing migration methods cannot handle complex velocity variations commonly found near such salt structures. Instead the authors use the full 3D acoustic wave equation, discretized via a finite difference algorithm. They reduce the cost of solving the apraxial wave equation by a number of numerical techniques including the method of fractional steps and pipelining the tridiagonal solves. The imaging code, Salvo, uses both frequency parallelism (generally 90% efficient) and spatial parallelism (65% efficient). Salvo has been tested on synthetic and real data and produces clear images of the subsurface even beneath complicated salt structures.

  10. 3-D Seismic Tomographic Modelling of the North-Western Spitsbergen Area

    NASA Astrophysics Data System (ADS)

    Czuba, W.

    2015-12-01

    Deep seismic sounding measurements were performed in the continent-ocean transition zone of the north-western Svalbard continental margin in 1976 - 1999 in an international co-operation. Seismic energy (airgun and TNT shots) was recorded by land (onshore) seismic stations, ocean bottom seismometers (OBS), and ocean bottom hydrophone systems (OBH). Data from archival and modern seismic profiles were altogether used for 3-D tomographic inversion using JIVE3D software. The modelling area was chosen to be a rectangle of 420 x 330 km (Fig.). The results are similar to the earlier 2-D modelling, supplemented by off-line information from the profiles and the SPITS permanent station, giving a 3-D image of the crustal structure and Moho interface shape. The continental crust thins to the west and north. A minimum depth of about 6 km to the Moho discontinuity was found east of the Molloy Deep and in the Knipovich Ridge. The Moho interface deepens to about 30 km beneath the continental crust of Spitsbergen.

  11. 3-D SAR image formation from sparse aperture data using 3-D target grids

    NASA Astrophysics Data System (ADS)

    Bhalla, Rajan; Li, Junfei; Ling, Hao

    2005-05-01

    The performance of ATR systems can potentially be improved by using three-dimensional (3-D) SAR images instead of the traditional two-dimensional SAR images or one-dimensional range profiles. 3-D SAR image formation of targets from radar backscattered data collected on wide angle, sparse apertures has been identified by AFRL as fundamental to building an object detection and recognition capability. A set of data has been released as a challenge problem. This paper describes a technique based on the concept of 3-D target grids aimed at the formation of 3-D SAR images of targets from sparse aperture data. The 3-D target grids capture the 3-D spatial and angular scattering properties of the target and serve as matched filters for SAR formation. The results of 3-D SAR formation using the backhoe public release data are presented.

  12. Rapid 360 degree imaging and stitching of 3D objects using multiple precision 3D cameras

    NASA Astrophysics Data System (ADS)

    Lu, Thomas; Yin, Stuart; Zhang, Jianzhong; Li, Jiangan; Wu, Frank

    2008-02-01

    In this paper, we present the system architecture of a 360 degree view 3D imaging system. The system consists of multiple 3D sensors synchronized to take 3D images around the object. Each 3D camera employs a single high-resolution digital camera and a color-coded light projector. The cameras are synchronized to rapidly capture the 3D and color information of a static object or a live person. The color encoded structure lighting ensures the precise reconstruction of the depth of the object. A 3D imaging system architecture is presented. The architecture employs the displacement of the camera and the projector to triangulate the depth information. The 3D camera system has achieved high depth resolution down to 0.1mm on a human head sized object and 360 degree imaging capability.

  13. 3D Buildings Extraction from Aerial Images

    NASA Astrophysics Data System (ADS)

    Melnikova, O.; Prandi, F.

    2011-09-01

    This paper introduces a semi-automatic method for buildings extraction through multiple-view aerial image analysis. The advantage of the used semi-automatic approach is that it allows processing of each building individually finding the parameters of buildings features extraction more precisely for each area. On the early stage the presented technique uses an extraction of line segments that is done only inside of areas specified manually. The rooftop hypothesis is used further to determine a subset of quadrangles, which could form building roofs from a set of extracted lines and corners obtained on the previous stage. After collecting of all potential roof shapes in all images overlaps, the epipolar geometry is applied to find matching between images. This allows to make an accurate selection of building roofs removing false-positive ones and to identify their global 3D coordinates given camera internal parameters and coordinates. The last step of the image matching is based on geometrical constraints in contrast to traditional correlation. The correlation is applied only in some highly restricted areas in order to find coordinates more precisely, in such a way significantly reducing processing time of the algorithm. The algorithm has been tested on a set of Milan's aerial images and shows highly accurate results.

  14. Automatic needle segmentation in 3D ultrasound images using 3D Hough transform

    NASA Astrophysics Data System (ADS)

    Zhou, Hua; Qiu, Wu; Ding, Mingyue; Zhang, Songgeng

    2007-12-01

    3D ultrasound (US) is a new technology that can be used for a variety of diagnostic applications, such as obstetrical, vascular, and urological imaging, and has been explored greatly potential in the applications of image-guided surgery and therapy. Uterine adenoma and uterine bleeding are the two most prevalent diseases in Chinese woman, and a minimally invasive ablation system using an RF button electrode which is needle-like is being used to destroy tumor cells or stop bleeding currently. Now a 3D US guidance system has been developed to avoid accidents or death of the patient by inaccurate localizations of the electrode and the tumor position during treatment. In this paper, we described two automated techniques, the 3D Hough Transform (3DHT) and the 3D Randomized Hough Transform (3DRHT), which is potentially fast, accurate, and robust to provide needle segmentation in 3D US image for use of 3D US imaging guidance. Based on the representation (Φ , θ , ρ , α ) of straight lines in 3D space, we used the 3DHT algorithm to segment needles successfully assumed that the approximate needle position and orientation are known in priori. The 3DRHT algorithm was developed to detect needles quickly without any information of the 3D US images. The needle segmentation techniques were evaluated using the 3D US images acquired by scanning water phantoms. The experiments demonstrated the feasibility of two 3D needle segmentation algorithms described in this paper.

  15. Photogrammetric 3D reconstruction using mobile imaging

    NASA Astrophysics Data System (ADS)

    Fritsch, Dieter; Syll, Miguel

    2015-03-01

    In our paper we demonstrate the development of an Android Application (AndroidSfM) for photogrammetric 3D reconstruction that works on smartphones and tablets likewise. The photos are taken with mobile devices, and can thereafter directly be calibrated using standard calibration algorithms of photogrammetry and computer vision, on that device. Due to still limited computing resources on mobile devices, a client-server handshake using Dropbox transfers the photos to the sever to run AndroidSfM for the pose estimation of all photos by Structure-from-Motion and, thereafter, uses the oriented bunch of photos for dense point cloud estimation by dense image matching algorithms. The result is transferred back to the mobile device for visualization and ad-hoc on-screen measurements.

  16. Imaging a Sustainable Future in 3D

    NASA Astrophysics Data System (ADS)

    Schuhr, W.; Lee, J. D.; Kanngieser, E.

    2012-07-01

    It is the intention of this paper, to contribute to a sustainable future by providing objective object information based on 3D photography as well as promoting 3D photography not only for scientists, but also for amateurs. Due to the presentation of this article by CIPA Task Group 3 on "3D Photographs in Cultural Heritage", the presented samples are masterpieces of historic as well as of current 3D photography concentrating on cultural heritage. In addition to a report on exemplarily access to international archives of 3D photographs, samples for new 3D photographs taken with modern 3D cameras, as well as by means of a ground based high resolution XLITE staff camera and also 3D photographs taken from a captive balloon and the use of civil drone platforms are dealt with. To advise on optimum suited 3D methodology, as well as to catch new trends in 3D, an updated synoptic overview of the 3D visualization technology, even claiming completeness, has been carried out as a result of a systematic survey. In this respect, e.g., today's lasered crystals might be "early bird" products in 3D, which, due to lack in resolution, contrast and color, remember to the stage of the invention of photography.

  17. Ames Lab 101: Real-Time 3D Imaging

    ScienceCinema

    Zhang, Song

    2012-08-29

    Ames Laboratory scientist Song Zhang explains his real-time 3-D imaging technology. The technique can be used to create high-resolution, real-time, precise, 3-D images for use in healthcare, security, and entertainment applications.

  18. Imaging PVC gas pipes using 3-D GPR

    SciTech Connect

    Bradford, J.; Ramaswamy, M.; Peddy, C.

    1996-11-01

    Over the years, many enhancements have been made by the oil and gas industry to improve the quality of seismic images. The GPR project at GTRI borrows heavily from these technologies in order to produce 3-D GPR images of PVC gas pipes. As will be demonstrated, improvements in GPR data acquisition, 3-D processing and visualization schemes yield good images of PVC pipes in the subsurface. Data have been collected in cooperation with the local gas company and at a test facility in Texas. Surveys were conducted over both a metal pipe and PVC pipes of diameters ranging from {1/2} in. to 4 in. at depths from 1 ft to 3 ft in different soil conditions. The metal pipe produced very good reflections and was used to fine tune and optimize the processing run stream. It was found that the following steps significantly improve the overall image: (1) Statics for drift and topography compensation, (2) Deconvolution, (3) Filtering and automatic gain control, (4) Migration for focusing and resolution, and (5) Visualization optimization. The processing flow implemented is relatively straightforward, simple to execute and robust under varying conditions. Future work will include testing resolution limits, effects of soil conditions, and leak detection.

  19. Progress in 3D imaging and display by integral imaging

    NASA Astrophysics Data System (ADS)

    Martinez-Cuenca, R.; Saavedra, G.; Martinez-Corral, M.; Pons, A.; Javidi, B.

    2009-05-01

    Three-dimensionality is currently considered an important added value in imaging devices, and therefore the search for an optimum 3D imaging and display technique is a hot topic that is attracting important research efforts. As main value, 3D monitors should provide the observers with different perspectives of a 3D scene by simply varying the head position. Three-dimensional imaging techniques have the potential to establish a future mass-market in the fields of entertainment and communications. Integral imaging (InI), which can capture true 3D color images, has been seen as the right technology to 3D viewing to audiences of more than one person. Due to the advanced degree of development, InI technology could be ready for commercialization in the coming years. This development is the result of a strong research effort performed along the past few years by many groups. Since Integral Imaging is still an emerging technology, the first aim of the "3D Imaging and Display Laboratory" at the University of Valencia, has been the realization of a thorough study of the principles that govern its operation. Is remarkable that some of these principles have been recognized and characterized by our group. Other contributions of our research have been addressed to overcome some of the classical limitations of InI systems, like the limited depth of field (in pickup and in display), the poor axial and lateral resolution, the pseudoscopic-to-orthoscopic conversion, the production of 3D images with continuous relief, or the limited range of viewing angles of InI monitors.

  20. 3D object-oriented image analysis in 3D geophysical modelling: Analysing the central part of the East African Rift System

    NASA Astrophysics Data System (ADS)

    Fadel, I.; van der Meijde, M.; Kerle, N.; Lauritsen, N.

    2015-03-01

    Non-uniqueness of satellite gravity interpretation has traditionally been reduced by using a priori information from seismic tomography models. This reduction in the non-uniqueness has been based on velocity-density conversion formulas or user interpretation of the 3D subsurface structures (objects) based on the seismic tomography models and then forward modelling these objects. However, this form of object-based approach has been done without a standardized methodology on how to extract the subsurface structures from the 3D models. In this research, a 3D object-oriented image analysis (3D OOA) approach was implemented to extract the 3D subsurface structures from geophysical data. The approach was applied on a 3D shear wave seismic tomography model of the central part of the East African Rift System. Subsequently, the extracted 3D objects from the tomography model were reconstructed in the 3D interactive modelling environment IGMAS+, and their density contrast values were calculated using an object-based inversion technique to calculate the forward signal of the objects and compare it with the measured satellite gravity. Thus, a new object-based approach was implemented to interpret and extract the 3D subsurface objects from 3D geophysical data. We also introduce a new approach to constrain the interpretation of the satellite gravity measurements that can be applied using any 3D geophysical model.

  1. Concurrent 3-D motion segmentation and 3-D interpretation of temporal sequences of monocular images.

    PubMed

    Sekkati, Hicham; Mitiche, Amar

    2006-03-01

    The purpose of this study is to investigate a variational method for joint multiregion three-dimensional (3-D) motion segmentation and 3-D interpretation of temporal sequences of monocular images. Interpretation consists of dense recovery of 3-D structure and motion from the image sequence spatiotemporal variations due to short-range image motion. The method is direct insomuch as it does not require prior computation of image motion. It allows movement of both viewing system and multiple independently moving objects. The problem is formulated following a variational statement with a functional containing three terms. One term measures the conformity of the interpretation within each region of 3-D motion segmentation to the image sequence spatiotemporal variations. The second term is of regularization of depth. The assumption that environmental objects are rigid accounts automatically for the regularity of 3-D motion within each region of segmentation. The third and last term is for the regularity of segmentation boundaries. Minimization of the functional follows the corresponding Euler-Lagrange equations. This results in iterated concurrent computation of 3-D motion segmentation by curve evolution, depth by gradient descent, and 3-D motion by least squares within each region of segmentation. Curve evolution is implemented via level sets for topology independence and numerical stability. This algorithm and its implementation are verified on synthetic and real image sequences. Viewers presented with anaglyphs of stereoscopic images constructed from the algorithm's output reported a strong perception of depth. PMID:16519351

  2. Seismic Imaging Processing and Migration

    2000-06-26

    Salvo is a 3D, finite difference, prestack, depth migration code for parallel computers. It is also capable of processing 2D and poststack data. The code requires as input a seismic dataset, a velocity model and a file of parameters that allows the user to select various options. The code uses this information to produce a seismic image. Some of the options available to the user include the application of various filters and imaging conditions. Themore » code also incorporates phase encoding (patent applied for) to process multiple shots simultaneously.« less

  3. Seismic Imaging and Monitoring

    SciTech Connect

    Huang, Lianjie

    2012-07-09

    I give an overview of LANL's capability in seismic imaging and monitoring. I present some seismic imaging and monitoring results, including imaging of complex structures, subsalt imaging of Gulf of Mexico, fault/fracture zone imaging for geothermal exploration at the Jemez pueblo, time-lapse imaging of a walkway vertical seismic profiling data for monitoring CO{sub 2} inject at SACROC, and microseismic event locations for monitoring CO{sub 2} injection at Aneth. These examples demonstrate LANL's high-resolution and high-fidelity seismic imaging and monitoring capabilities.

  4. 3D Modelling of Seismically Active Parts of Underground Faults via Seismic Data Mining

    NASA Astrophysics Data System (ADS)

    Frantzeskakis, Theofanis; Konstantaras, Anthony

    2015-04-01

    During the last few years rapid steps have been taken towards drilling for oil in the western Mediterranean sea. Since most of the countries in the region benefit mainly from tourism and considering that the Mediterranean is a closed sea only replenishing its water once every ninety years careful measures are being taken to ensure safe drilling. In that concept this research work attempts to derive a three dimensional model of the seismically active parts of the underlying underground faults in areas of petroleum interest. For that purpose seismic spatio-temporal clustering has been applied to seismic data to identify potential distinct seismic regions in the area of interest. Results have been coalesced with two dimensional maps of underground faults from past surveys and seismic epicentres, having followed careful reallocation processing, have been used to provide information regarding the vertical extent of multiple underground faults in the region of interest. The end product is a three dimensional map of the possible underground location and extent of the seismically active parts of underground faults. Indexing terms: underground faults modelling, seismic data mining, 3D visualisation, active seismic source mapping, seismic hazard evaluation, dangerous phenomena modelling Acknowledgment This research work is supported by the ESPA Operational Programme, Education and Life Long Learning, Students Practical Placement Initiative. References [1] Alves, T.M., Kokinou, E. and Zodiatis, G.: 'A three-step model to assess shoreline and offshore susceptibility to oil spills: The South Aegean (Crete) as an analogue for confined marine basins', Marine Pollution Bulletin, In Press, 2014 [2] Ciappa, A., Costabile, S.: 'Oil spill hazard assessment using a reverse trajectory method for the Egadi marine protected area (Central Mediterranean Sea)', Marine Pollution Bulletin, vol. 84 (1-2), pp. 44-55, 2014 [3] Ganas, A., Karastathis, V., Moshou, A., Valkaniotis, S., Mouzakiotis

  5. Vector Acoustics, Vector Sensors, and 3D Underwater Imaging

    NASA Astrophysics Data System (ADS)

    Lindwall, D.

    2007-12-01

    Vector acoustic data has two more dimensions of information than pressure data and may allow for 3D underwater imaging with much less data than with hydrophone data. The vector acoustic sensors measures the particle motions due to passing sound waves and, in conjunction with a collocated hydrophone, the direction of travel of the sound waves. When using a controlled source with known source and sensor locations, the reflection points of the sound field can be determined with a simple trigonometric calculation. I demonstrate this concept with an experiment that used an accelerometer based vector acoustic sensor in a water tank with a short-pulse source and passive scattering targets. The sensor consists of a three-axis accelerometer and a matched hydrophone. The sound source was a standard transducer driven by a short 7 kHz pulse. The sensor was suspended in a fixed location and the hydrophone was moved about the tank by a robotic arm to insonify the tank from many locations. Several floats were placed in the tank as acoustic targets at diagonal ranges of approximately one meter. The accelerometer data show the direct source wave as well as the target scattered waves and reflections from the nearby water surface, tank bottom and sides. Without resorting to the usual methods of seismic imaging, which in this case is only two dimensional and relied entirely on the use of a synthetic source aperture, the two targets, the tank walls, the tank bottom, and the water surface were imaged. A directional ambiguity inherent to vector sensors is removed by using collocated hydrophone data. Although this experiment was in a very simple environment, it suggests that 3-D seismic surveys may be achieved with vector sensors using the same logistics as a 2-D survey that uses conventional hydrophones. This work was supported by the Office of Naval Research, program element 61153N.

  6. Automatic needle segmentation in 3D ultrasound images using 3D improved Hough transform

    NASA Astrophysics Data System (ADS)

    Zhou, Hua; Qiu, Wu; Ding, Mingyue; Zhang, Songgen

    2008-03-01

    3D ultrasound (US) is a new technology that can be used for a variety of diagnostic applications, such as obstetrical, vascular, and urological imaging, and has been explored greatly potential in the applications of image-guided surgery and therapy. Uterine adenoma and uterine bleeding are the two most prevalent diseases in Chinese woman, and a minimally invasive ablation system using a needle-like RF button electrode is widely used to destroy tumor cells or stop bleeding. To avoid accidents or death of the patient by inaccurate localizations of the electrode and the tumor position during treatment, 3D US guidance system was developed. In this paper, a new automated technique, the 3D Improved Hough Transform (3DIHT) algorithm, which is potentially fast, accurate, and robust to provide needle segmentation in 3D US image for use of 3D US imaging guidance, was presented. Based on the coarse-fine search strategy and a four parameter representation of lines in 3D space, 3DIHT algorithm can segment needles quickly, accurately and robustly. The technique was evaluated using the 3D US images acquired by scanning a water phantom. The segmentation position deviation of the line was less than 2mm and angular deviation was much less than 2°. The average computational time measured on a Pentium IV 2.80GHz PC computer with a 381×381×250 image was less than 2s.

  7. 3-D seismic velocity and attenuation structures in the geothermal field

    SciTech Connect

    Nugraha, Andri Dian; Syahputra, Ahmad; Fatkhan,; Sule, Rachmat

    2013-09-09

    We conducted delay time tomography to determine 3-D seismic velocity structures (Vp, Vs, and Vp/Vs ratio) using micro-seismic events in the geothermal field. The P-and S-wave arrival times of these micro-seismic events have been used as input for the tomographic inversion. Our preliminary seismic velocity results show that the subsurface condition of geothermal field can be fairly delineated the characteristic of reservoir. We then extended our understanding of the subsurface physical properties through determining of attenuation structures (Qp, Qs, and Qs/Qp ratio) using micro-seismic waveform. We combined seismic velocities and attenuation structures to get much better interpretation of the reservoir characteristic. Our preliminary attanuation structures results show reservoir characterization can be more clearly by using the 3-D attenuation model of Qp, Qs, and Qs/Qp ratio combined with 3-D seismic velocity model of Vp, Vs, and Vp/Vs ratio.

  8. 3-D Seismic Exploration Project, Ute Indian Tribe, Uintah and Ouray Reservation, Uintah County, Utah

    SciTech Connect

    Eckels, Marc T.

    2002-09-09

    The objectives of this North Hill Creek 3-D seismic survey were to: (1) cover as large an area as possible with available budget; (2) obtain high quality data throughout the depth range of the prospective geologic formations of 2,000' to 12,000' to image both gross structures and more subtle structural and stratigraphic elements; (3) overcome the challenges posed by a hard, reflective sandstone that cropped out or was buried just a few feet below the surface under most of the survey area; and (4) run a safe survey.

  9. 3-D visualisation and interpretation of seismic attributes extracted from large 3-D seismic datasets: Subregional and prospect evaluation, deepwater Nigeria

    SciTech Connect

    Sola, M.; Haakon Nordby, L.; Dailey, D.V.; Duncan, E.A. )

    1996-01-01

    High resolution 3-D visualization of horizon interpretation and seismic attributes from large 3-D seismic surveys in deepwater Nigeria has greatly enhanced the exploration team's ability to quickly recognize prospective segments of subregional and prospect specific scale areas. Integrated workstation generated structure, isopach and extracted horizon consistent, interval and windowed attributes are particularly useful in illustrating the complex structural and stratigraphical prospectivity of deepwater Nigeria. Large 3-D seismic volumes acquired over 750 square kilometers can be manipulated within the visualization system with attribute tracking capability that allows for real time data interrogation and interpretation. As in classical seismic stratigraphic studies, pattern recognition is fundamental to effective depositions facies interpretation and reservoir model construction. The 3-D perspective enhances the data interpretation through clear representation of relative scale, spatial distribution and magnitude of attributes. In deepwater Nigeria, many prospective traps rely on an interplay between syndepositional structure and slope turbidite depositional systems. Reservoir systems in many prospects appear to be dominated by unconfined to moderately focused slope feeder channel facies. These units have spatially complex facies architecture with feeder channel axes separated by extensive interchannel areas. Structural culminations generally have a history of initial compressional folding with late in extensional collapse and accommodation faulting. The resulting complex trap configurations often have stacked reservoirs over intervals as thick as 1500 meters. Exploration, appraisal and development scenarios in these settings can be optimized by taking full advantage of integrating high resolution 3-D visualization and seismic workstation interpretation.

  10. 3-D visualisation and interpretation of seismic attributes extracted from large 3-D seismic datasets: Subregional and prospect evaluation, deepwater Nigeria

    SciTech Connect

    Sola, M.; Haakon Nordby, L.; Dailey, D.V.; Duncan, E.A.

    1996-12-31

    High resolution 3-D visualization of horizon interpretation and seismic attributes from large 3-D seismic surveys in deepwater Nigeria has greatly enhanced the exploration team`s ability to quickly recognize prospective segments of subregional and prospect specific scale areas. Integrated workstation generated structure, isopach and extracted horizon consistent, interval and windowed attributes are particularly useful in illustrating the complex structural and stratigraphical prospectivity of deepwater Nigeria. Large 3-D seismic volumes acquired over 750 square kilometers can be manipulated within the visualization system with attribute tracking capability that allows for real time data interrogation and interpretation. As in classical seismic stratigraphic studies, pattern recognition is fundamental to effective depositions facies interpretation and reservoir model construction. The 3-D perspective enhances the data interpretation through clear representation of relative scale, spatial distribution and magnitude of attributes. In deepwater Nigeria, many prospective traps rely on an interplay between syndepositional structure and slope turbidite depositional systems. Reservoir systems in many prospects appear to be dominated by unconfined to moderately focused slope feeder channel facies. These units have spatially complex facies architecture with feeder channel axes separated by extensive interchannel areas. Structural culminations generally have a history of initial compressional folding with late in extensional collapse and accommodation faulting. The resulting complex trap configurations often have stacked reservoirs over intervals as thick as 1500 meters. Exploration, appraisal and development scenarios in these settings can be optimized by taking full advantage of integrating high resolution 3-D visualization and seismic workstation interpretation.

  11. 3D spatial resolution and spectral resolution of interferometric 3D imaging spectrometry.

    PubMed

    Obara, Masaki; Yoshimori, Kyu

    2016-04-01

    Recently developed interferometric 3D imaging spectrometry (J. Opt. Soc. Am A18, 765 [2001]1084-7529JOAOD610.1364/JOSAA.18.000765) enables obtainment of the spectral information and 3D spatial information for incoherently illuminated or self-luminous object simultaneously. Using this method, we can obtain multispectral components of complex holograms, which correspond directly to the phase distribution of the wavefronts propagated from the polychromatic object. This paper focuses on the analysis of spectral resolution and 3D spatial resolution in interferometric 3D imaging spectrometry. Our analysis is based on a novel analytical impulse response function defined over four-dimensional space. We found that the experimental results agree well with the theoretical prediction. This work also suggests a new criterion and estimate method regarding 3D spatial resolution of digital holography. PMID:27139648

  12. 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

    SciTech Connect

    Levander, Alan R.

    2005-06-01

    Gian Fradelizio, a Rice Ph.D. student has completed reprocessing the 3D seismic reflection data acquired at Hill AFB through post-stack depth migration for comparison to the traveltime and waveform tomography results. Zelt, Levander, Fradelizio, and 5 others spent a week at Hill AFB in September 2005, acquiring an elastic wave data set along 2 profiles. We used 60 3-component Galperin mounted 40 Hz geophones recorded by 3 GEOMETRICS Stratavision systems. The seismic source employed was a sledgehammer used to generate transverse, and radial, and vertical point source data. Data processing has begun at Rice to generate S-wave reflection and refraction images. We also acquired surface wave and ground penetrating rada data to complement the elastic wave dataset.

  13. Automatic 2D-to-3D image conversion using 3D examples from the internet

    NASA Astrophysics Data System (ADS)

    Konrad, J.; Brown, G.; Wang, M.; Ishwar, P.; Wu, C.; Mukherjee, D.

    2012-03-01

    The availability of 3D hardware has so far outpaced the production of 3D content. Although to date many methods have been proposed to convert 2D images to 3D stereopairs, the most successful ones involve human operators and, therefore, are time-consuming and costly, while the fully-automatic ones have not yet achieved the same level of quality. This subpar performance is due to the fact that automatic methods usually rely on assumptions about the captured 3D scene that are often violated in practice. In this paper, we explore a radically different approach inspired by our work on saliency detection in images. Instead of relying on a deterministic scene model for the input 2D image, we propose to "learn" the model from a large dictionary of stereopairs, such as YouTube 3D. Our new approach is built upon a key observation and an assumption. The key observation is that among millions of stereopairs available on-line, there likely exist many stereopairs whose 3D content matches that of the 2D input (query). We assume that two stereopairs whose left images are photometrically similar are likely to have similar disparity fields. Our approach first finds a number of on-line stereopairs whose left image is a close photometric match to the 2D query and then extracts depth information from these stereopairs. Since disparities for the selected stereopairs differ due to differences in underlying image content, level of noise, distortions, etc., we combine them by using the median. We apply the resulting median disparity field to the 2D query to obtain the corresponding right image, while handling occlusions and newly-exposed areas in the usual way. We have applied our method in two scenarios. First, we used YouTube 3D videos in search of the most similar frames. Then, we repeated the experiments on a small, but carefully-selected, dictionary of stereopairs closely matching the query. This, to a degree, emulates the results one would expect from the use of an extremely large 3D

  14. Full-Waveform Validation of a 3D Seismic Model for Western US

    NASA Astrophysics Data System (ADS)

    Maceira, M.; Larmat, C. S.; Ammon, C. J.; Chai, C.; Herrmann, R. B.

    2014-12-01

    Since the initiation of tomographic studies in the 1970s, geoscientists have advanced the art of inferring 3D variations in the subsurface using collections of geophysical (primarily seismic) observables recorded at or near Earth's surface. Advances have come from improvement and enhancement of the available data and from research on theoretical and computational improvements to tomographic and generalized inverse methods. In the last decade, utilizing dense array datasets, these efforts have led to unprecedented 3D images of the subsurface. Understandably, less effort has been expended on model validation to provide an absolute assessment of model uncertainty. Generally models constructed with different data sets and independent computational codes are assessed with geological reasonability and compared other models to gain confidence. The question of "How good is a particular 3D geophysical model at representing the Earth's true nature?" remains largely unaddressed at a time when 3D Earth models are used for both societal and energy security. In the last few years, opportunities have arisen in earth-structure imaging, including the advent of new methods in computational seismology and statistical sciences. We use the unique and extensive High Performance Computing resources available at Los Alamos National Laboratory to explore approaches to realistic model validation. We present results from a study focused on validating a 3D model for the western United States generated using a joint inversion simultaneously fitting interpolated teleseismic P-wave receiver functions, Rayleigh-wave group-velocity estimates between 7 and 250 s period, and high-wavenumber filtered Bouguer gravity observations. Validation of the obtained model is performed through systematic comparison of observed and predicted seismograms generated using the Spectral Element Method, which is a direct numerical solution for full waveform modeling in 3D models, with accuracy of spectral methods.

  15. Complex patterns of faulting revealed by 3D seismic data at the West Galicia rifted margin

    NASA Astrophysics Data System (ADS)

    Reston, Timothy; Cresswell, Derren; Sawyer, Dale; Ranero, Cesar; Shillington, Donna; Morgan, Julia; Lymer, Gael

    2015-04-01

    The west Galicia margin is characterised by crust thinning to less than 3 km, well-defined fault blocks, which overlie a bright reflection (the S reflector) generally interpreted as a tectonic Moho. The margin exhibits neither voluminous magmatism nor thick sediment piles to obscure the structures and the amount of extension. As such is represents an ideal location to study the process of continental breakup both through seismic imaging and potentially through drilling. Prestack depth migration of existing 2D profiles has strongly supported the interpretation of the S reflector as both a detachment and as the crust-mantle boundary; wide-angle seismic has also shown that the mantle beneath S is serpentinised. Despite the quality of the existing 2D seismic images, a number of competing models have been advanced to explain the formation of this margin, including sequential faulting, polyphase faulting, multiple detachments and the gravitational collapse of the margin over exhumed mantle. As these models, all developed for the Galicia margin, have been subsequently applied to other margins, distinguishing between them has implications not only for the structure of the Galicia margin but for the process of rifting through to breakup more generally. To address these issues in summer of 2013 we collected a 3D combined seismic reflection and wide-angle dataset over this margin. Here we present some of the results of ongoing processing of the 3D volume, focussing on the internal structure of some of the fault blocks that overlies the S detachment. 2D processing of the data shows a relatively simple series of tilted fault block, bound by west-dipping faults that detach downwards onto the bright S reflector. However, inspection of the 3D volume produced by 3D pre-stack time migration reveals that the fault blocks contain a complex set of sedimentary packages, with strata tilted to the east, west, north and south, each package bound by faults. Furthermore, the top of crustal

  16. Seismic performance of a novel 3D isolation system on continuous bridges

    NASA Astrophysics Data System (ADS)

    Ou, J. P.; Jia, J. F.

    2010-04-01

    Remarkable vertical seismic motion is one of the prominent characteristics of the near-fault earthquake motions, but the traditional and widely used base isolation system only can effectively mitigate horizontal seismic responses and structural damage. A promising three-dimensional (3D) seismic isolation bearing, consisting of laminated rubber bearing with lead core (LRB) and combined coned disc spring with vertical energy dissipation device (e.g., inner fluid viscous cylindric damper or steel damper), was proposed to mitigate horizontal and vertical structural seismic responses simultaneously and separately. Three-group seismic ground motion records were selected to validate the effectiveness of the proposed 3D seismic isolation bearing on a continuous slab bridge. The appropriate damping of the vertical damping device was presented by parametric study. The analyses results showed that the proposed 3D isolation bearing is essentially effective to mitigate vertical and horizontal structural seismic response simultaneously. Near-fault pulse-type seismic motions should be considered in seismic isolation design and evaluation. The proper damping ratio of the vertical damping device should be 20%-30% for favorable vertical isolation effectiveness. The proposed 3D seismic isolation bearing is promising to be applied to the mediate-to-short span bridge and even some building structures.

  17. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    SciTech Connect

    Morimoto, A.K.; Bow, W.J.; Strong, D.S.

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  18. A 3D image analysis tool for SPECT imaging

    NASA Astrophysics Data System (ADS)

    Kontos, Despina; Wang, Qiang; Megalooikonomou, Vasileios; Maurer, Alan H.; Knight, Linda C.; Kantor, Steve; Fisher, Robert S.; Simonian, Hrair P.; Parkman, Henry P.

    2005-04-01

    We have developed semi-automated and fully-automated tools for the analysis of 3D single-photon emission computed tomography (SPECT) images. The focus is on the efficient boundary delineation of complex 3D structures that enables accurate measurement of their structural and physiologic properties. We employ intensity based thresholding algorithms for interactive and semi-automated analysis. We also explore fuzzy-connectedness concepts for fully automating the segmentation process. We apply the proposed tools to SPECT image data capturing variation of gastric accommodation and emptying. These image analysis tools were developed within the framework of a noninvasive scintigraphic test to measure simultaneously both gastric emptying and gastric volume after ingestion of a solid or a liquid meal. The clinical focus of the particular analysis was to probe associations between gastric accommodation/emptying and functional dyspepsia. Employing the proposed tools, we outline effectively the complex three dimensional gastric boundaries shown in the 3D SPECT images. We also perform accurate volume calculations in order to quantitatively assess the gastric mass variation. This analysis was performed both with the semi-automated and fully-automated tools. The results were validated against manual segmentation performed by a human expert. We believe that the development of an automated segmentation tool for SPECT imaging of the gastric volume variability will allow for other new applications of SPECT imaging where there is a need to evaluate complex organ function or tumor masses.

  19. Assessing a 3D smoothed seismicity model of induced earthquakes

    NASA Astrophysics Data System (ADS)

    Zechar, Jeremy; Király, Eszter; Gischig, Valentin; Wiemer, Stefan

    2016-04-01

    As more energy exploration and extraction efforts cause earthquakes, it becomes increasingly important to control induced seismicity. Risk management schemes must be improved and should ultimately be based on near-real-time forecasting systems. With this goal in mind, we propose a test bench to evaluate models of induced seismicity based on metrics developed by the CSEP community. To illustrate the test bench, we consider a model based on the so-called seismogenic index and a rate decay; to produce three-dimensional forecasts, we smooth past earthquakes in space and time. We explore four variants of this model using the Basel 2006 and Soultz-sous-Forêts 2004 datasets to make short-term forecasts, test their consistency, and rank the model variants. Our results suggest that such a smoothed seismicity model is useful for forecasting induced seismicity within three days, and giving more weight to recent events improves forecast performance. Moreover, the location of the largest induced earthquake is forecast well by this model. Despite the good spatial performance, the model does not estimate the seismicity rate well: it frequently overestimates during stimulation and during the early post-stimulation period, and it systematically underestimates around shut-in. In this presentation, we also describe a robust estimate of information gain, a modification that can also benefit forecast experiments involving tectonic earthquakes.

  20. 3D Imaging with Holographic Tomography

    NASA Astrophysics Data System (ADS)

    Sheppard, Colin J. R.; Kou, Shan Shan

    2010-04-01

    There are two main types of tomography that enable the 3D internal structures of objects to be reconstructed from scattered data. The commonly known computerized tomography (CT) give good results in the x-ray wavelength range where the filtered back-projection theorem and Radon transform can be used. These techniques rely on the Fourier projection-slice theorem where rays are considered to propagate straight through the object. Another type of tomography called `diffraction tomography' applies in applications in optics and acoustics where diffraction and scattering effects must be taken into account. The latter proves to be a more difficult problem, as light no longer travels straight through the sample. Holographic tomography is a popular way of performing diffraction tomography and there has been active experimental research on reconstructing complex refractive index data using this approach recently. However, there are two distinct ways of doing tomography: either by rotation of the object or by rotation of the illumination while fixing the detector. The difference between these two setups is intuitive but needs to be quantified. From Fourier optics and information transformation point of view, we use 3D transfer function analysis to quantitatively describe how spatial frequencies of the object are mapped to the Fourier domain. We first employ a paraxial treatment by calculating the Fourier transform of the defocused OTF. The shape of the calculated 3D CTF for tomography, by scanning the illumination in one direction only, takes on a form that we might call a 'peanut,' compared to the case of object rotation, where a diablo is formed, the peanut exhibiting significant differences and non-isotropy. In particular, there is a line singularity along one transverse direction. Under high numerical aperture conditions, the paraxial treatment is not accurate, and so we make use of 3D analytical geometry to calculate the behaviour in the non-paraxial case. This time, we

  1. Reducing Non-Uniqueness in Satellite Gravity Inversion using 3D Object Oriented Image Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Fadel, I.; van der Meijde, M.; Kerle, N.

    2013-12-01

    Non-uniqueness of satellite gravity interpretation has been usually reduced by using a priori information from various sources, e.g. seismic tomography models. The reduction in non-uniqueness has been based on velocity-density conversion formulas or user interpretation for 3D subsurface structures (objects) in seismic tomography models. However, these processes introduce additional uncertainty through the conversion relations due to the dependency on the other physical parameters such as temperature and pressure, or through the bias in the interpretation due to user choices and experience. In this research, a new methodology is introduced to extract the 3D subsurface structures from 3D geophysical data using a state-of-art 3D Object Oriented Image Analysis (OOA) technique. 3D OOA is tested using a set of synthetic models that simulate the real situation in the study area of this research. Then, 3D OOA is used to extract 3D subsurface objects from a real 3D seismic tomography model. The extracted 3D objects are used to reconstruct a forward model and its response is compared with the measured satellite gravity. Finally, the result of the forward modelling, based on the extracted 3D objects, is used to constrain the inversion process of satellite gravity data. Through this work, a new object-based approach is introduced to interpret and extract the 3D subsurface objects from 3D geophysical data. This can be used to constrain modelling and inversion of potential field data using the extracted 3D subsurface structures from other methods. In summary, a new approach is introduced to constrain inversion of satellite gravity measurements and enhance interpretation capabilities.

  2. 3D Full Seismic Waveform Tomography of NW Turkey and Surroundings

    NASA Astrophysics Data System (ADS)

    Cubuk, Yesim; Fichtner, Andreas; Taymaz, Tuncay

    2015-04-01

    Northward collision of the Arabian plate with the Eurasian plate, and interaction of the motion between dynamic processes originated from the subduction of the African plate beneath the Aegean generated very complex tectonic structures in the study region. Western Turkey is among one of the most active extensional regions in the world and the study area is mainly located where the extensional Aegean and the right-lateral strike-slip North Anatolian Fault Zone (NAFZ) intersects. Therefore, the tectonic framework of the NW Turkey and the Marmara region is mainly characterized by the transition between the strike-slip tectonics to the extensional tectonics. The Sea of Marmara region has been subjected to several active and passive seismic investigations, nevertheless the accurate knowledge on the heterogeneity in the crust and upper mantle beneath the study area still remains enigmatic. On small-scale tomography problems, seismograms strongly reflect the effects of heterogeneities and the scattering properties of the Earth. Thus, the knowledge of high-resolution seismic imaging with an improved 3D radially anisotropic crustal model of the NW Turkey will enable better localization of earthquakes, identification of faults as well as the improvement of the seismic hazard assessment. For this purpose, we aim to develop 3D radially anisotropic subsurface structure of the Sea of Marmara and NW Turkey crust based on full waveform adjoint tomography method. The earthquake data were principally obtained from the Kandilli Observatory and Earthquake Research Institute (KOERI) and Earthquake Research Center (AFAD-DAD) database. In addition to this, some of the seismic waveform data extracted from the Hellenic Unified Seismic Network (HUSN) stations that are located within our study region were also used in this study. We have selected and simulated waveforms of earthquakes with magnitudes 4.0 ≤ Mw ≤ 6.7 occurred in the period between 2007-2014 to determine the 3D velocity

  3. An Integrated Multi-component Processing and Interpretation Framework for 3D Borehole Seismic Data

    SciTech Connect

    M. Karrenbach

    2004-04-01

    to perform advanced processing, imaging and analysis tests in the future during this project. Preparation of our software libraries for interfacing 3C display classes and mechanisms were carried out. We extensively tested the OIV and QT software library for usefulness in displaying 3C data and we thoroughly tested 3D scene graph communication between QT, OpenInventor and our existing software classes, which lead to optimizing the interface between them. We assembled an application skeleton which serves as a basis for future high level software tools. Based on this skeleton we implemented a 3C Work Bench tool as the primary prototyping tool for all future developments within this project. This work bench allows to load, manipulate and display data items. We demonstrated its basic functionality by loading source maps, horizons, seismic and velocity volumes, well logs into the tool, performing basic QC steps as is necessary in normal processing. All tasks were performed successfully, ensuring the continued progress of this project as outlined in the original proposal. Deliverables generated during this time period consist of reporting details and synthetically modeled seismic data for a 3D layered geological model. The numerically modeled SEGY data, as well as the model representation data, are ready to be sent out to DOE facilities for archiving. Based on the successful conclusion of work performed during this six month period we continue to generate synthetically modeled 3D borehole seismic data, according to Tasks 2 and 3. At the same time we proceed to design, implement and test according to the original plan the basic data classes and the basic framework outlined in Tasks 5 through 8.

  4. Light field display and 3D image reconstruction

    NASA Astrophysics Data System (ADS)

    Iwane, Toru

    2016-06-01

    Light field optics and its applications become rather popular in these days. With light field optics or light field thesis, real 3D space can be described in 2D plane as 4D data, which we call as light field data. This process can be divided in two procedures. First, real3D scene is optically reduced with imaging lens. Second, this optically reduced 3D image is encoded into light field data. In later procedure we can say that 3D information is encoded onto a plane as 2D data by lens array plate. This transformation is reversible and acquired light field data can be decoded again into 3D image with the arrayed lens plate. "Refocusing" (focusing image on your favorite point after taking a picture), light-field camera's most popular function, is some kind of sectioning process from encoded 3D data (light field data) to 2D image. In this paper at first I show our actual light field camera and our 3D display using acquired and computer-simulated light field data, on which real 3D image is reconstructed. In second I explain our data processing method whose arithmetic operation is performed not in Fourier domain but in real domain. Then our 3D display system is characterized by a few features; reconstructed image is of finer resolutions than density of arrayed lenses and it is not necessary to adjust lens array plate to flat display on which light field data is displayed.

  5. 3D Imaging with Structured Illumination for Advanced Security Applications

    SciTech Connect

    Birch, Gabriel Carisle; Dagel, Amber Lynn; Kast, Brian A.; Smith, Collin S.

    2015-09-01

    Three-dimensional (3D) information in a physical security system is a highly useful dis- criminator. The two-dimensional data from an imaging systems fails to provide target dis- tance and three-dimensional motion vector, which can be used to reduce nuisance alarm rates and increase system effectiveness. However, 3D imaging devices designed primarily for use in physical security systems are uncommon. This report discusses an architecture favorable to physical security systems; an inexpensive snapshot 3D imaging system utilizing a simple illumination system. The method of acquiring 3D data, tests to understand illumination de- sign, and software modifications possible to maximize information gathering capability are discussed.

  6. Full 3D microwave quasi-holographic imaging

    NASA Astrophysics Data System (ADS)

    Castelli, Juan-Carlos; Tardivel, Francois

    A full 3D quasi-holographic image processing technique developed by ONERA is described. A complex backscattering coefficient of a drone scale model was measured for discrete values of the 3D backscattered wave vector in a frequency range between 4.5-8 GHz. The 3D image processing is implemented on a HP 1000 mini-computer and will be part of LASER 2 software to be used in three RCS measurement indoor facilities.

  7. Geological characterisation of complex reservoirs using 3D seismic: Case studies

    NASA Astrophysics Data System (ADS)

    Benaissa, Zahia; Benaïssa, Abdelkader; Seghir Baghaoui, Mohamed; Bendali, Mohamed; Chami, Adel; Khelifi Touhami, Médina; Ouadfeul, Sid Ali; Boudella, Amar

    2014-05-01

    3D seismic allows getting a set of numerous closely-spaced seismic lines that provide a high spatially sampled measure of subsurface reflectivity. It leads to an accurate interpretation of seismic reflection data, which is one of the most important stages of a successful hydrocarbons exploration, especially in the reservoirs characterised by complex geological setting. We present here two case studies pertaining to two Algerian hydrocarbon fields. Considering the positive results obtained from 2D seismic interpretation, several wells were drilled. Some of them have proved dry, due certainly to inaccurate seismic interpretation because of non standard geological context. For the first case, the high quality of the 3D seismic data allowed to reveal, on all the inlines and crosslines, the existence of paleovalleys under the top of the Ordovician (unit IV) reservoir. The mapping of these paleovalleys clearly showed that the dry well, contrary to the other wells, was implanted outside paleovalleys. This fact was confirmed by the analysis of well data. The second case study concerns the problem of andesitic eruptive deposits on the top of the Ordovician reservoir, which condition the geometry and continuity of this reservoir and cause uncertainties in the mapping of the Hercynian unconformity. Well data associated with 3D seismic response shows that eruptive deposits generate high impedance anomaly because of the high density and velocity of andesites. We used this information to interpret these eruptive rocks as being responsible of high impedance anomalies, inside the Ordovician reservoir, on the impedance volume generated from the 3D seismic data. A 3D extraction of the anomalies allowed an accurate localisation of the andesites. So, it appears, according to these two case studies, that for an efficient recovery of hydrocarbons, we have to rely, first of all, on an accurate seismic interpretation before we use microscopic measurements. 3D seismic, once again, remains

  8. Volumetric image display for complex 3D data visualization

    NASA Astrophysics Data System (ADS)

    Tsao, Che-Chih; Chen, Jyh Shing

    2000-05-01

    A volumetric image display is a new display technology capable of displaying computer generated 3D images in a volumetric space. Many viewers can walk around the display and see the image from omni-directions simultaneously without wearing any glasses. The image is real and possesses all major elements in both physiological and psychological depth cues. Due to the volumetric nature of its image, the VID can provide the most natural human-machine interface in operations involving 3D data manipulation and 3D targets monitoring. The technology creates volumetric 3D images by projecting a series of profiling images distributed in the space form a volumetric image because of the after-image effect of human eyes. Exemplary applications in biomedical image visualization were tested on a prototype display, using different methods to display a data set from Ct-scans. The features of this display technology make it most suitable for applications that require quick understanding of the 3D relations, need frequent spatial interactions with the 3D images, or involve time-varying 3D data. It can also be useful for group discussion and decision making.

  9. On Alternative Approaches to 3D Image Perception: Monoscopic 3D Techniques

    NASA Astrophysics Data System (ADS)

    Blundell, Barry G.

    2015-06-01

    In the eighteenth century, techniques that enabled a strong sense of 3D perception to be experienced without recourse to binocular disparities (arising from the spatial separation of the eyes) underpinned the first significant commercial sales of 3D viewing devices and associated content. However following the advent of stereoscopic techniques in the nineteenth century, 3D image depiction has become inextricably linked to binocular parallax and outside the vision science and arts communities relatively little attention has been directed towards earlier approaches. Here we introduce relevant concepts and terminology and consider a number of techniques and optical devices that enable 3D perception to be experienced on the basis of planar images rendered from a single vantage point. Subsequently we allude to possible mechanisms for non-binocular parallax based 3D perception. Particular attention is given to reviewing areas likely to be thought-provoking to those involved in 3D display development, spatial visualization, HCI, and other related areas of interdisciplinary research.

  10. Multi-azimuth 3D Seismic Exploration and Processing in the Jeju Basin, the Northern East China Sea

    NASA Astrophysics Data System (ADS)

    Yoon, Youngho; Kang, Moohee; Kim, Jin-Ho; Kim, Kyong-O.

    2015-04-01

    Multi-azimuth(MAZ) 3D seismic exploration is one of the most advanced seismic survey methods to improve illumination and multiple attenuation for better image of the subsurface structures. 3D multi-channel seismic data were collected in two phases during 2012, 2013, and 2014 in Jeju Basin, the northern part of the East China Sea Basin where several oil and gas fields were discovered. Phase 1 data were acquired at 135° and 315° azimuths in 2012 and 2013 comprised a full 3D marine seismic coverage of 160 km2. In 2014, phase 2 data were acquired at the azimuths 45° and 225°, perpendicular to those of phase 1. These two datasets were processed through the same processing workflow prior to velocity analysis and merged to one MAZ dataset. We performed velocity analysis on the MAZ dataset as well as two phases data individually and then stacked these three datasets separately. We were able to pick more accurate velocities in the MAZ dataset compare to phase 1 and 2 data while velocity picking. Consequently, the MAZ seismic volume provide us better resolution and improved images since different shooting directions illuminate different parts of the structures and stratigraphic features.

  11. 3-D seismic response of buried pipelines laid through fault

    SciTech Connect

    Liang, J.W.

    1995-12-31

    An ideal model for the non-causative fault is put forward in which the fault is assumed to be composed by three horizontally adjacent soil media. Dynamic behaviors of pipelines laid through the fault is analyzed. Although simple, this model may qualitatively illustrate the accumulation of seismic waves in the fault, so illustrate the dynamic behaviors of the pipelines. The results show that, the fault is materially different from a two soil site even if the fault width is very narrow, and the dynamic behaviors of the pipelines laid through the fault are determined by the fault width, the stiffness ratio of the three soil media, and the type of the seismic waves.

  12. 3D augmented reality with integral imaging display

    NASA Astrophysics Data System (ADS)

    Shen, Xin; Hua, Hong; Javidi, Bahram

    2016-06-01

    In this paper, a three-dimensional (3D) integral imaging display for augmented reality is presented. By implementing the pseudoscopic-to-orthoscopic conversion method, elemental image arrays with different capturing parameters can be transferred into the identical format for 3D display. With the proposed merging algorithm, a new set of elemental images for augmented reality display is generated. The newly generated elemental images contain both the virtual objects and real world scene with desired depth information and transparency parameters. The experimental results indicate the feasibility of the proposed 3D augmented reality with integral imaging.

  13. 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

    SciTech Connect

    Levander, Alan R.

    2004-12-01

    Under ER63662, 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface, we have completed a number of subprojects associated with the Hill Air Force Base (HAFB) high resolution 3-D reflection/tomography dataset.

  14. New results from a 3D seismic academic dataset across the west Galicia margin

    NASA Astrophysics Data System (ADS)

    Lymer, Gaël; Cresswell, Derren; Reston, Tim; Stevenson, Carl; Sawyer, Dale

    2016-04-01

    The west Galicia margin (western Spain) is a magma-poor margin and has limited sedimentary cover, providing ideal conditions to study the processes of continental extension and break-up through seismic imaging. The margin is characterised by hyper-extended continental crust, well defined rotated faults blocks with associated syn-kinematic sedimentary wedges, and exhumed serpentinized continental mantle. Faulted blocks overlie a bright reflection, the S reflector, generally interpreted as both a detachment and the crust-mantle boundary. But open questions remain concerning the role of the S detachment in extension leading to breakup. To study further the S reflection and its role in continental breakup, a new 3D high-resolution multi-channel seismic dataset has been acquired over the Galicia margin during summer 2013. It consists in 800 inlines and 5000 crosslines distributed on a ~680 km2 areal. This 3D dataset is thus the largest academic one of its kind. It extends across the edge of the continental crust and captures the 3D nature of extension and break-up of the northern Atlantic continental margins. Here we present some results from our interpretations of the 3D volume, which allow various horizons, including the base of the post-rift sedimentary cover, the top basement and the S reflector, to be mapped out in 3D. These maps provide 3D views of the margin structure and also reveal the texture of each horizon. We also focus on the internal structure of some of the faulted blocks through interpretation of the crustal normal faults. The main normal faults are generally connected downward on the S reflector, revealing strong interactions between crustal thinning and the S. The half-grabens and the fault blocks are dominantly N-S oriented, but the crustal structures vary both along strike and cross strike. We particularly observe an intriguingly NW-SE trend, highlighted by a pronounced low within the crest of the fault blocks. We also observe this trend from

  15. Validating 3D Seismic Velocity Models Using the Spectral Element Method

    NASA Astrophysics Data System (ADS)

    Maceira, M.; Rowe, C. A.; Allen, R. M.; Obrebski, M. J.

    2010-12-01

    As seismic instrumentation, data storage and dissemination and computational power improve, seismic velocity models attempt to resolve smaller structures and cover larger areas. However, it is unclear how accurate these velocity models are and, while the best models available are used for event determination, it is difficult to put uncertainties on seismic event parameters. Model validation is typically done using resolution tests that assume the imaging theory used is accurate and thus only considers the impact of the data coverage on resolution. We present the results of a more rigorous approach to model validation via full three-dimensional waveform propagation using Spectral Element Methods (SEM). This approach makes no assumptions about the theory used to generate the models but require substantial computational resources. We first validate 3D tomographic models for the Western USA generated using both ray-theoretical and finite-frequency methods. The Dynamic North America (DNA) Models of P- and S- velocity structure (DNA09-P and DNA09-S) use teleseismic body-wave traveltime residuals recorded at over 800 seismic stations provided by the Earthscope USArray and regional seismic networks. We performed systematic computations of synthetics for the dataset used to generate the DNA models. Direct comparison of these synthetic seismograms to the actual observations allows us to accurately assess and validate the models. Implementation of the method for a densely instrumented region such as that covered by the DNA model provides a useful testbed for the validation methods that we will subsequently apply to other, more challenging study areas.

  16. SCEC/CME CyberShake: Probabilistic Seismic Hazard Analysis Using 3D Seismic Waveform Modeling

    NASA Astrophysics Data System (ADS)

    Callaghan, S.; Maechling, P. J.; Cui, Y.; Faerman, M.; Field, E.; Graves, R.; Gupta, N.; Gupta, V.; Jordan, T. H.; Kesselman, C.; Mehta, G.; Okaya, D.; Vahi, K.; Zhao, L.

    2005-12-01

    Researchers on the SCEC Community Modeling Environment (SCEC/CME) Project are calculating Probabilistic Seismic Hazard Curves for several sites in the Los Angeles area. The hazard curves calculated in this study use Intensity Measure Relationships (IMRs) based on 3D ground motion simulations rather than on attenuation relationships. State-of-the-art Probabilistic Seismic Hazard Analysis (PSHA) is currently conducted using IMRs that use empirically-based attenuation relationships. These attenuation relationships represent relatively simple analytical models based on the regression of observed data. However, it is widely believed that significant improvements in SHA will rely on the use of more physics-based, waveform modeling. In fact, a more physics-based approach to PSHA was endorsed in a recent assessment of earthquake science by National Research Council (2003). In order to introduce the use of 3D seismic waveform modeling into PSHA hazard curve calculations, the SCEC/CME CyberShake group is integrating state-of-the-art PSHA software tools (OpenSHA), SCEC-developed geophysical models (SCEC CVM3.0), validated anelastic wave modeling (AWM) software, and state-of-the-art computational technologies including high performance computing and grid-based scientific workflows in an effort to develop an OpenSHA-compatible 3D waveform-based IMR component. This will allow researchers to combine a new class of waveform-based IMRs with the large number of existing PSHA components, such as Earthquake Rupture Forecasts (ERF's), that are currently implemented in the OpenSHA system. To calculate a probabilistic hazard curve for a site of interest, we use the OpenSHA implementation of the NSHMP-2002 ERF and identify all ruptures within 200km of the site of interest. For each of these ruptures, we convert the NSHMP-2002 rupture definition into one, or more, Ruptures with Slip Time History (Rupture Variations) using newly developed Rupture Generator software. Strain Green Tensors are

  17. 3D interpretation of SHARAD radargram data using seismic processing routines

    NASA Astrophysics Data System (ADS)

    Kleuskens, M. H. P.; Oosthoek, J. H. P.

    2009-04-01

    engineering software package Petrel of Schlumberger to interpret the radar data in 3D, using its powerful seismic interpretation tool. Since the radardata does not contain an absolute vertical time reference, the surface reflection in the radargram is referenced to the Mars Orbiter Laser Altimeter (MOLA) topography data of the region. By doing this, we can visualize all radar traces in 3D and interpret the combined 3D dataset altogether. Furthermore, MOLA and high resolution satellite images can be projected simultaneously in Petrel as a reference. This method gives much more insight in the data than analyzing each 2D radargram individually: an anomaly that is spotted in a 2D radargram can be validated by a radargram that is positioned perpendicular to the first one. This method helps us to distinguish between different layers and detect instrument and cross-track anomalies. Furthermore, we can perform automatic analyses such as estimating volumes of different formations. This helps us to understand the formation process of the ice cap.

  18. 3D, 9-C anisotropic seismic modeling and inversion

    NASA Astrophysics Data System (ADS)

    Rusmanugroho, Herurisa

    The most complete representation of an elastic medium consists of an elastic tensor with 21 independent moduli. All 21 can be estimated from compressional and shear wave polarization and slowness vectors corresponding to wide apertures of polar and azimuth angles. In isotropic media, when seismic source and receiver components have the same orientation (such as XX and YY), the reflection amplitude contours align approximately perpendicular to the particle motions. The mixed components (such as XY and YX) have amplitude patterns that are in symmetrical pairs of either the same, or of opposite, polarity on either side of the diagonal of the 9-C response matrix. In anisotropic media, amplitude variations with azimuth show the same basic patterns and symmetries as for isotropic, but with a superimposed tendency for alignment parallel to the strike of the vertical cracks. Solutions for elastic tensor elements from synthetic slowness and polarization data calculated directly from the Christoffel equation are more sensitive to the polar angle aperture than to the azimuth aperture. Nine-component synthetic elastic vertical seismic profile data for a model with triclinic symmetry calculated by finite-differencing allows estimation of the elastic 21 tensor elements in the vicinity of a three-component borehole receiver. Wide polar angle and azimuth apertures are needed for accurately estimating the elastic tensor elements. The tensor elements become less independent as the data apertures decrease. Results obtained by extracting slowness and polarization data from the corresponding synthetic seismograms show similar results. The inversion algorithm has produced good results from field vertical seismic profile data set from the Weyburn Field in Southern Saskatchewan in Canada. Synthetic nine-component seismograms calculated from the extracted tensor are able to explain most of the significant features in the field data. The inverted stiffness elastic tensor shows orthorhombic

  19. 3D model-based still image object categorization

    NASA Astrophysics Data System (ADS)

    Petre, Raluca-Diana; Zaharia, Titus

    2011-09-01

    This paper proposes a novel recognition scheme algorithm for semantic labeling of 2D object present in still images. The principle consists of matching unknown 2D objects with categorized 3D models in order to infer the semantics of the 3D object to the image. We tested our new recognition framework by using the MPEG-7 and Princeton 3D model databases in order to label unknown images randomly selected from the web. Results obtained show promising performances, with recognition rate up to 84%, which opens interesting perspectives in terms of semantic metadata extraction from still images/videos.

  20. 3D Cell Culture Imaging with Digital Holographic Microscopy

    NASA Astrophysics Data System (ADS)

    Dimiduk, Thomas; Nyberg, Kendra; Almeda, Dariela; Koshelva, Ekaterina; McGorty, Ryan; Kaz, David; Gardel, Emily; Auguste, Debra; Manoharan, Vinothan

    2011-03-01

    Cells in higher organisms naturally exist in a three dimensional (3D) structure, a fact sometimes ignored by in vitro biological research. Confinement to a two dimensional culture imposes significant deviations from the native 3D state. One of the biggest obstacles to wider use of 3D cultures is the difficulty of 3D imaging. The confocal microscope, the dominant 3D imaging instrument, is expensive, bulky, and light-intensive; live cells can be observed for only a short time before they suffer photodamage. We present an alternative 3D imaging techinque, digital holographic microscopy, which can capture 3D information with axial resolution better than 2 μm in a 100 μm deep volume. Capturing a 3D image requires only a single camera exposure with a sub-millisecond laser pulse, allowing us to image cell cultures using five orders of magnitude less light energy than with confocal. This can be done with hardware costing ~ 1000. We use the instrument to image growth of MCF7 breast cancer cells and p. pastoras yeast. We acknowledge support from NSF GRFP.

  1. 3D imaging using projected dynamic fringes

    NASA Astrophysics Data System (ADS)

    Shaw, Michael M.; Atkinson, John T.; Harvey, David M.; Hobson, Clifford A.; Lalor, Michael J.

    1994-12-01

    An instrument capable of highly accurate, non-contact range measurement has been developed, which is based upon the principle of projected rotating fringes. More usually known as dynamic fringe projection, it is this technique which is exploited in the dynamic automated range transducer (DART). The intensity waveform seen at the target and sensed by the detector, contains all the information required to accurately determine the fringe order. This, in turn, allows the range to be evaluated by the substitution of the fringe order into a simple algebraic expression. Various techniques for the analysis of the received intensity signals from the surface of the target have been investigated. The accuracy to which the range can be determined ultimately depends upon the accuracy to which the fringe order can be evaluated from the received intensity waveform. It is extremely important to be able to closely determine the fractional fringe order value, to achieve any meaningful results. This paper describes a number of techniques which have been used to analyze the intensity waveform, and critically appraises their suitability in terms of accuracy and required speed of operation. This work also examines the development of this instrument for three-dimensional measurements based on single or two beam systems. Using CCD array detectors, a 3-D range map of the object's surface may be produced.

  2. Imaging hypoxia using 3D photoacoustic spectroscopy

    NASA Astrophysics Data System (ADS)

    Stantz, Keith M.

    2010-02-01

    Purpose: The objective is to develop a multivariate in vivo hemodynamic model of tissue oxygenation (MiHMO2) based on 3D photoacoustic spectroscopy. Introduction: Low oxygen levels, or hypoxia, deprives cancer cells of oxygen and confers resistance to irradiation, some chemotherapeutic drugs, and oxygen-dependent therapies (phototherapy) leading to treatment failure and poor disease-free and overall survival. For example, clinical studies of patients with breast carcinomas, cervical cancer, and head and neck carcinomas (HNC) are more likely to suffer local reoccurrence and metastasis if their tumors are hypoxic. A novel method to non invasively measure tumor hypoxia, identify its type, and monitor its heterogeneity is devised by measuring tumor hemodynamics, MiHMO2. Material and Methods: Simulations are performed to compare tumor pO2 levels and hypoxia based on physiology - perfusion, fractional plasma volume, fractional cellular volume - and its hemoglobin status - oxygen saturation and hemoglobin concentration - based on in vivo measurements of breast, prostate, and ovarian tumors. Simulations of MiHMO2 are performed to assess the influence of scanner resolutions and different mathematic models of oxygen delivery. Results: Sensitivity of pO2 and hypoxic fraction to photoacoustic scanner resolution and dependencies on model complexity will be presented using hemodynamic parameters for different tumors. Conclusions: Photoacoustic CT spectroscopy provides a unique ability to monitor hemodynamic and cellular physiology in tissue, which can be used to longitudinally monitor tumor oxygenation and its response to anti-angiogenic therapies.

  3. Highway 3D model from image and lidar data

    NASA Astrophysics Data System (ADS)

    Chen, Jinfeng; Chu, Henry; Sun, Xiaoduan

    2014-05-01

    We present a new method of highway 3-D model construction developed based on feature extraction in highway images and LIDAR data. We describe the processing road coordinate data that connect the image frames to the coordinates of the elevation data. Image processing methods are used to extract sky, road, and ground regions as well as significant objects (such as signs and building fronts) in the roadside for the 3D model. LIDAR data are interpolated and processed to extract the road lanes as well as other features such as trees, ditches, and elevated objects to form the 3D model. 3D geometry reasoning is used to match the image features to the 3D model. Results from successive frames are integrated to improve the final model.

  4. Compression of 3D integral images using wavelet decomposition

    NASA Astrophysics Data System (ADS)

    Mazri, Meriem; Aggoun, Amar

    2003-06-01

    This paper presents a wavelet-based lossy compression technique for unidirectional 3D integral images (UII). The method requires the extraction of different viewpoint images from the integral image. A single viewpoint image is constructed by extracting one pixel from each microlens, then each viewpoint image is decomposed using a Two Dimensional Discrete Wavelet Transform (2D-DWT). The resulting array of coefficients contains several frequency bands. The lower frequency bands of the viewpoint images are assembled and compressed using a 3 Dimensional Discrete Cosine Transform (3D-DCT) followed by Huffman coding. This will achieve decorrelation within and between 2D low frequency bands from the different viewpoint images. The remaining higher frequency bands are Arithmetic coded. After decoding and decompression of the viewpoint images using an inverse 3D-DCT and an inverse 2D-DWT, each pixel from every reconstructed viewpoint image is put back into its original position within the microlens to reconstruct the whole 3D integral image. Simulations were performed on a set of four different grey level 3D UII using a uniform scalar quantizer with deadzone. The results for the average of the four UII intensity distributions are presented and compared with previous use of 3D-DCT scheme. It was found that the algorithm achieves better rate-distortion performance, with respect to compression ratio and image quality at very low bit rates.

  5. Diffractive optical element for creating visual 3D images.

    PubMed

    Goncharsky, Alexander; Goncharsky, Anton; Durlevich, Svyatoslav

    2016-05-01

    A method is proposed to compute and synthesize the microrelief of a diffractive optical element to produce a new visual security feature - the vertical 3D/3D switch effect. The security feature consists in the alternation of two 3D color images when the diffractive element is tilted up/down. Optical security elements that produce the new security feature are synthesized using electron-beam technology. Sample optical security elements are manufactured that produce 3D to 3D visual switch effect when illuminated by white light. Photos and video records of the vertical 3D/3D switch effect of real optical elements are presented. The optical elements developed can be replicated using standard equipment employed for manufacturing security holograms. The new optical security feature is easy to control visually, safely protected against counterfeit, and designed to protect banknotes, documents, ID cards, etc. PMID:27137530

  6. SEISVIZ3D: Stereoscopic system for the representation of seismic data - Interpretation and Immersion

    NASA Astrophysics Data System (ADS)

    von Hartmann, Hartwig; Rilling, Stefan; Bogen, Manfred; Thomas, Rüdiger

    2015-04-01

    The seismic method is a valuable tool for getting 3D-images from the subsurface. Seismic data acquisition today is not only a topic for oil and gas exploration but is used also for geothermal exploration, inspections of nuclear waste sites and for scientific investigations. The system presented in this contribution may also have an impact on the visualization of 3D-data of other geophysical methods. 3D-seismic data can be displayed in different ways to give a spatial impression of the subsurface.They are a combination of individual vertical cuts, possibly linked to a cubical portion of the data volume, and the stereoscopic view of the seismic data. By these methods, the spatial perception for the structures and thus of the processes in the subsurface should be increased. Stereoscopic techniques are e. g. implemented in the CAVE and the WALL, both of which require a lot of space and high technical effort. The aim of the interpretation system shown here is stereoscopic visualization of seismic data at the workplace, i.e. at the personal workstation and monitor. The system was developed with following criteria in mind: • Fast rendering of large amounts of data so that a continuous view of the data when changing the viewing angle and the data section is possible, • defining areas in stereoscopic view to translate the spatial impression directly into an interpretation, • the development of an appropriate user interface, including head-tracking, for handling the increased degrees of freedom, • the possibility of collaboration, i.e. teamwork and idea exchange with the simultaneous viewing of a scene at remote locations. The possibilities offered by the use of a stereoscopic system do not replace a conventional interpretation workflow. Rather they have to be implemented into it as an additional step. The amplitude distribution of the seismic data is a challenge for the stereoscopic display because the opacity level and the scaling and selection of the data have to

  7. Seismic waves in 3-D: from mantle asymmetries to reliable seismic hazard assessment

    NASA Astrophysics Data System (ADS)

    Panza, Giuliano F.; Romanelli, Fabio

    2014-10-01

    A global cross-section of the Earth parallel to the tectonic equator (TE) path, the great circle representing the equator of net lithosphere rotation, shows a difference in shear wave velocities between the western and eastern flanks of the three major oceanic rift basins. The low-velocity layer in the upper asthenosphere, at a depth range of 120 to 200 km, is assumed to represent the decoupling between the lithosphere and the underlying mantle. Along the TE-perturbed (TE-pert) path, a ubiquitous LVZ, about 1,000-km-wide and 100-km-thick, occurs in the asthenosphere. The existence of the TE-pert is a necessary prerequisite for the existence of a continuous global flow within the Earth. Ground-shaking scenarios were constructed using a scenario-based method for seismic hazard analysis (NDSHA), using realistic and duly validated synthetic time series, and generating a data bank of several thousands of seismograms that account for source, propagation, and site effects. Accordingly, with basic self-organized criticality concepts, NDSHA permits the integration of available information provided by the most updated seismological, geological, geophysical, and geotechnical databases for the site of interest, as well as advanced physical modeling techniques, to provide a reliable and robust background for the development of a design basis for cultural heritage and civil infrastructures. Estimates of seismic hazard obtained using the NDSHA and standard probabilistic approaches are compared for the Italian territory, and a case-study is discussed. In order to enable a reliable estimation of the ground motion response to an earthquake, three-dimensional velocity models have to be considered, resulting in a new, very efficient, analytical procedure for computing the broadband seismic wave-field in a 3-D anelastic Earth model.

  8. 3D scene reconstruction from multi-aperture images

    NASA Astrophysics Data System (ADS)

    Mao, Miao; Qin, Kaihuai

    2014-04-01

    With the development of virtual reality, there is a growing demand for 3D modeling of real scenes. This paper proposes a novel 3D scene reconstruction framework based on multi-aperture images. Our framework consists of four parts. Firstly, images with different apertures are captured via programmable aperture. Secondly, we use SIFT method for feature point matching. Then we exploit binocular stereo vision to calculate camera parameters and 3D positions of matching points, forming a sparse 3D scene model. Finally, we apply patch-based multi-view stereo to obtain a dense 3D scene model. Experimental results show that our method is practical and effective to reconstruct dense 3D scene.

  9. Dedicated 3D photoacoustic breast imaging

    PubMed Central

    Kruger, Robert A.; Kuzmiak, Cherie M.; Lam, Richard B.; Reinecke, Daniel R.; Del Rio, Stephen P.; Steed, Doreen

    2013-01-01

    Purpose: To report the design and imaging methodology of a photoacoustic scanner dedicated to imaging hemoglobin distribution throughout a human breast. Methods: The authors developed a dedicated breast photoacoustic mammography (PAM) system using a spherical detector aperture based on our previous photoacoustic tomography scanner. The system uses 512 detectors with rectilinear scanning. The scan shape is a spiral pattern whose radius varies from 24 to 96 mm, thereby allowing a field of view that accommodates a wide range of breast sizes. The authors measured the contrast-to-noise ratio (CNR) using a target comprised of 1-mm dots printed on clear plastic. Each dot absorption coefficient was approximately the same as a 1-mm thickness of whole blood at 756 nm, the output wavelength of the Alexandrite laser used by this imaging system. The target was immersed in varying depths of an 8% solution of stock Liposyn II-20%, which mimics the attenuation of breast tissue (1.1 cm−1). The spatial resolution was measured using a 6 μm-diameter carbon fiber embedded in agar. The breasts of four healthy female volunteers, spanning a range of breast size from a brassiere C cup to a DD cup, were imaged using a 96-mm spiral protocol. Results: The CNR target was clearly visualized to a depth of 53 mm. Spatial resolution, which was estimated from the full width at half-maximum of a profile across the PAM image of a carbon fiber, was 0.42 mm. In the four human volunteers, the vasculature was well visualized throughout the breast tissue, including to the chest wall. Conclusions: CNR, lateral field-of-view and penetration depth of our dedicated PAM scanning system is sufficient to image breasts as large as 1335 mL, which should accommodate up to 90% of the women in the United States. PMID:24320471

  10. 3-D capacitance density imaging system

    DOEpatents

    Fasching, G.E.

    1988-03-18

    A three-dimensional capacitance density imaging of a gasified bed or the like in a containment vessel is achieved using a plurality of electrodes provided circumferentially about the bed in levels and along the bed in channels. The electrodes are individually and selectively excited electrically at each level to produce a plurality of current flux field patterns generated in the bed at each level. The current flux field patterns are suitably sensed and a density pattern of the bed at each level determined. By combining the determined density patterns at each level, a three-dimensional density image of the bed is achieved. 7 figs.

  11. Polarimetric 3D integral imaging in photon-starved conditions.

    PubMed

    Carnicer, Artur; Javidi, Bahram

    2015-03-01

    We develop a method for obtaining 3D polarimetric integral images from elemental images recorded in low light illumination conditions. Since photon-counting images are very sparse, calculation of the Stokes parameters and the degree of polarization should be handled carefully. In our approach, polarimetric 3D integral images are generated using the Maximum Likelihood Estimation and subsequently reconstructed by means of a Total Variation Denoising filter. In this way, polarimetric results are comparable to those obtained in conventional illumination conditions. We also show that polarimetric information retrieved from photon starved images can be used in 3D object recognition problems. To the best of our knowledge, this is the first report on 3D polarimetric photon counting integral imaging. PMID:25836861

  12. Image performance evaluation of a 3D surgical imaging platform

    NASA Astrophysics Data System (ADS)

    Petrov, Ivailo E.; Nikolov, Hristo N.; Holdsworth, David W.; Drangova, Maria

    2011-03-01

    The O-arm (Medtronic Inc.) is a multi-dimensional surgical imaging platform. The purpose of this study was to perform a quantitative evaluation of the imaging performance of the O-arm in an effort to understand its potential for future nonorthopedic applications. Performance of the reconstructed 3D images was evaluated, using a custom-built phantom, in terms of resolution, linearity, uniformity and geometrical accuracy. Both the standard (SD, 13 s) and high definition (HD, 26 s) modes were evaluated, with the imaging parameters set to image the head (120 kVp, 100 mAs and 150 mAs, respectively). For quantitative noise characterization, the images were converted to Hounsfield units (HU) off-line. Measurement of the modulation transfer function revealed a limiting resolution (at 10% level) of 1.0 mm-1 in the axial dimension. Image noise varied between 15 and 19 HU for the HD and SD modes, respectively. Image intensities varied linearly over the measured range, up to 1300 HU. Geometric accuracy was maintained in all three dimensions over the field of view. The present study has evaluated the performance characteristics of the O-arm, and demonstrates feasibility for use in interventional applications and quantitative imaging tasks outside those currently targeted by the manufacturer. Further improvements to the reconstruction algorithms may further enhance performance for lower-contrast applications.

  13. Phase Sensitive Cueing for 3D Objects in Overhead Images

    SciTech Connect

    Paglieroni, D

    2005-02-04

    Locating specific 3D objects in overhead images is an important problem in many remote sensing applications. 3D objects may contain either one connected component or multiple disconnected components. Solutions must accommodate images acquired with diverse sensors at various times of the day, in various seasons of the year, or under various weather conditions. Moreover, the physical manifestation of a 3D object with fixed physical dimensions in an overhead image is highly dependent on object physical dimensions, object position/orientation, image spatial resolution, and imaging geometry (e.g., obliqueness). This paper describes a two-stage computer-assisted approach for locating 3D objects in overhead images. In the matching stage, the computer matches models of 3D objects to overhead images. The strongest degree of match over all object orientations is computed at each pixel. Unambiguous local maxima in the degree of match as a function of pixel location are then found. In the cueing stage, the computer sorts image thumbnails in descending order of figure-of-merit and presents them to human analysts for visual inspection and interpretation. The figure-of-merit associated with an image thumbnail is computed from the degrees of match to a 3D object model associated with unambiguous local maxima that lie within the thumbnail. This form of computer assistance is invaluable when most of the relevant thumbnails are highly ranked, and the amount of inspection time needed is much less for the highly ranked thumbnails than for images as a whole.

  14. 3D laser imaging for concealed object identification

    NASA Astrophysics Data System (ADS)

    Berechet, Ion; Berginc, Gérard; Berechet, Stefan

    2014-09-01

    This paper deals with new optical non-conventional 3D laser imaging. Optical non-conventional imaging explores the advantages of laser imaging to form a three-dimensional image of the scene. 3D laser imaging can be used for threedimensional medical imaging, topography, surveillance, robotic vision because of ability to detect and recognize objects. In this paper, we present a 3D laser imaging for concealed object identification. The objective of this new 3D laser imaging is to provide the user a complete 3D reconstruction of the concealed object from available 2D data limited in number and with low representativeness. The 2D laser data used in this paper come from simulations that are based on the calculation of the laser interactions with the different interfaces of the scene of interest and from experimental results. We show the global 3D reconstruction procedures capable to separate objects from foliage and reconstruct a threedimensional image of the considered object. In this paper, we present examples of reconstruction and completion of three-dimensional images and we analyse the different parameters of the identification process such as resolution, the scenario of camouflage, noise impact and lacunarity degree.

  15. Recovering physical property information from subduction plate boundaries using 3D full-waveform seismic inversion

    NASA Astrophysics Data System (ADS)

    Bell, R. E.; Morgan, J. V.; Warner, M.

    2013-12-01

    Our understanding of subduction margin seismogenesis has been revolutionised in the last couple of decades with the discovery that the size of the seismogenic zone may not be controlled simply by temperature and a broad spectrum of seismic behaviour exists from stick-slip to stable sliding. Laboratory and numerical experiments suggest that physical properties, particularly fluid pressure may play an important role in controlling the seismic behaviour of subduction margins. Although drilling can provide information on physical properties along subduction thrust faults at point locations at relatively shallow depths, correlations between physical properties and seismic velocity using rock physics relationships are required to resolve physical properties along the margin and down-dip. Therefore, high resolution seismic velocity models are key to recovering physical property information at subduction plate boundaries away from drill sites. 3D Full waveform inversion (FWI) is a technique pioneered by the oil industry to obtain high-resolution high-fidelity models of physical properties in the sub-surface. 3D FWI involves the inversion of low-frequency (>2 to <7 Hz), early arriving (principally transmitted) seismic data, to recover the macro (intermediate to long-wavelength) velocity structure. Although 2D FWI has been used to improve velocity models of subduction plate boundaries before, 3D FWI has not yet been attempted. 3D inversions have superior convergence and accuracy, as they sample the subsurface with multi-azimuth multiply-crossing wavefields. In this contribution we perform a suite of synthetic tests to investigate if 3D FWI could be used to better resolve physical property information along subduction margin plate boundaries using conventionally collected 3D seismic data. We base our analysis on the Muroto Basin area of the Nankai margin and investigate if the acquisition parameters and geometry of the subduction margin render 3D seismic data collected across

  16. A 3D Level Set Method for Microwave Breast Imaging

    PubMed Central

    Colgan, Timothy J.; Hagness, Susan C.; Van Veen, Barry D.

    2015-01-01

    Objective Conventional inverse-scattering algorithms for microwave breast imaging result in moderate resolution images with blurred boundaries between tissues. Recent 2D numerical microwave imaging studies demonstrate that the use of a level set method preserves dielectric boundaries, resulting in a more accurate, higher resolution reconstruction of the dielectric properties distribution. Previously proposed level set algorithms are computationally expensive and thus impractical in 3D. In this paper we present a computationally tractable 3D microwave imaging algorithm based on level sets. Methods We reduce the computational cost of the level set method using a Jacobian matrix, rather than an adjoint method, to calculate Frechet derivatives. We demonstrate the feasibility of 3D imaging using simulated array measurements from 3D numerical breast phantoms. We evaluate performance by comparing full 3D reconstructions to those from a conventional microwave imaging technique. We also quantitatively assess the efficacy of our algorithm in evaluating breast density. Results Our reconstructions of 3D numerical breast phantoms improve upon those of a conventional microwave imaging technique. The density estimates from our level set algorithm are more accurate than those of conventional microwave imaging, and the accuracy is greater than that reported for mammographic density estimation. Conclusion Our level set method leads to a feasible level of computational complexity for full 3D imaging, and reconstructs the heterogeneous dielectric properties distribution of the breast more accurately than conventional microwave imaging methods. Significance 3D microwave breast imaging using a level set method is a promising low-cost, non-ionizing alternative to current breast imaging techniques. PMID:26011863

  17. 3D/3D registration of coronary CTA and biplane XA reconstructions for improved image guidance

    SciTech Connect

    Dibildox, Gerardo Baka, Nora; Walsum, Theo van; Punt, Mark; Aben, Jean-Paul; Schultz, Carl; Niessen, Wiro

    2014-09-15

    Purpose: The authors aim to improve image guidance during percutaneous coronary interventions of chronic total occlusions (CTO) by providing information obtained from computed tomography angiography (CTA) to the cardiac interventionist. To this end, the authors investigate a method to register a 3D CTA model to biplane reconstructions. Methods: The authors developed a method for registering preoperative coronary CTA with intraoperative biplane x-ray angiography (XA) images via 3D models of the coronary arteries. The models are extracted from the CTA and biplane XA images, and are temporally aligned based on CTA reconstruction phase and XA ECG signals. Rigid spatial alignment is achieved with a robust probabilistic point set registration approach using Gaussian mixture models (GMMs). This approach is extended by including orientation in the Gaussian mixtures and by weighting bifurcation points. The method is evaluated on retrospectively acquired coronary CTA datasets of 23 CTO patients for which biplane XA images are available. Results: The Gaussian mixture model approach achieved a median registration accuracy of 1.7 mm. The extended GMM approach including orientation was not significantly different (P > 0.1) but did improve robustness with regards to the initialization of the 3D models. Conclusions: The authors demonstrated that the GMM approach can effectively be applied to register CTA to biplane XA images for the purpose of improving image guidance in percutaneous coronary interventions.

  18. CO2 mass estimation visible in time-lapse 3D seismic data from a saline aquifer and uncertainties

    NASA Astrophysics Data System (ADS)

    Ivanova, A.; Lueth, S.; Bergmann, P.; Ivandic, M.

    2014-12-01

    At Ketzin (Germany) the first European onshore pilot scale project for geological storage of CO2 was initiated in 2004. This project is multidisciplinary and includes 3D time-lapse seismic monitoring. A 3D pre-injection seismic survey was acquired in 2005. Then CO2 injection into a sandstone saline aquifer started at a depth of 650 m in 2008. A 1st 3D seismic repeat survey was acquired in 2009 after 22 kilotons had been injected. The imaged CO2 signature was concentrated around the injection well (200-300 m). A 2nd 3D seismic repeat survey was acquired in 2012 after 61 kilotons had been injected. The imaged CO2 signature further extended (100-200 m). The injection was terminated in 2013. Totally 67 kilotons of CO2 were injected. Time-lapse seismic processing, petrophysical data and geophysical logging on CO2 saturation have allowed for an estimate of the amount of CO2 visible in the seismic data. This estimate is dependent upon a choice of a number of parameters and contains a number of uncertainties. The main uncertainties are following. The constant reservoir porosity and CO2 density used for the estimation are probably an over-simplification since the reservoir is quite heterogeneous. May be velocity dispersion is present in the Ketzin reservoir rocks, but we do not consider it to be large enough that it could affect the mass of CO2 in our estimation. There are only a small number of direct petrophysical observations, providing a weak statistical basis for the determination of seismic velocities based on CO2 saturation and we have assumed that the petrophysical experiments were carried out on samples that are representative for the average properties of the whole reservoir. Finally, the most of the time delay values in the both 3D seismic repeat surveys within the amplitude anomaly are near the noise level of 1-2 ms, however a change of 1 ms in the time delay affects significantly the mass estimate, thus the choice of the time-delay cutoff is crucial. In spite

  19. Subglacial Landforms and Processes: new Information From 3D Seismic Technology

    NASA Astrophysics Data System (ADS)

    Andreassen, K.

    2007-12-01

    Three-dimensional (3D) seismic interpretation and imaging techniques provide a unique means of investigating submarine geomorphic features produced by former ice sheets. An extensive two-dimensional (2D) and 3D seismic data base is here used to image the imprints left behind by glaciers that flowed out a major cross-shelf trough (Bjornoyrenna) of the north-Norwegian continental shelf during repeated glacial episodes. Mega-scale glacial lineations characterize the seafloor geomorphology of Bjornoyrenna and smaller, contributing cross-shelf troughs, where they are inferred to represent flow-lines of former ice streams that where active during the most recent (Weichselian) glacial period. Similar features are commonly observed on buried horizons. Large- scale seafloor imprints from an early readvance after the last glacial maximum are especially well preserved. Streamlined landforms and associated lobe-shaped ridges indicate that this major cross-shelf trough hosted six separate ice stream lobes that diverged fan-like at their margins, but were not all active simultaneously. A 300 km wide grounding-zone wedge results from high sediment flux within sub-ice stream deformable beds. A 2 to 3 km thick Pleistocene record is preserved at the mouth of Bjornoyrenna, in the Bjornoya Trough Mouth Fan. The preservation of up to several hundred meters of glacigenic sediments between the buried, glacially eroded surfaces, provides here the opportunity to study the internal structure of till units. 3D seismic attribute maps reveal that megablocks and rafts commonly occur within the till units. The sediments blocks are often aligned in chains that may be up to 2 km wide and over 50 km long. The largest individual megablocks have an areal extent of over 2 km2. The sediment chains are interpreted to have been eroded, transported and deposited by grounded ice, most probably fast-flowing ice streams. This is based on the relationship between the sediment chains and the horizons revealing

  20. Critical comparison of 3D imaging approaches

    SciTech Connect

    Bennett, C L

    1999-06-03

    Currently three imaging spectrometer architectures, tunable filter, dispersive, and Fourier transform, are viable for imaging the universe in three dimensions. There are domains of greatest utility for each of these architectures. The optimum choice among the various alternative architectures is dependent on the nature of the desired observations, the maturity of the relevant technology, and the character of the backgrounds. The domain appropriate for each of the alternatives is delineated; both for instruments having ideal performance as well as for instrumentation based on currently available technology. The environment and science objectives for the Next Generation Space Telescope will be used as a specific representative case to provide a basis for comparison of the various alternatives.

  1. 3-D Imaging Based, Radiobiological Dosimetry

    PubMed Central

    Sgouros, George; Frey, Eric; Wahl, Richard; He, Bin; Prideaux, Andrew; Hobbs, Robert

    2008-01-01

    Targeted radionuclide therapy holds promise as a new treatment against cancer. Advances in imaging are making it possible to evaluate the spatial distribution of radioactivity in tumors and normal organs over time. Matched anatomical imaging such as combined SPECT/CT and PET/CT have also made it possible to obtain tissue density information in conjunction with the radioactivity distribution. Coupled with sophisticated iterative reconstruction algorithims, these advances have made it possible to perform highly patient-specific dosimetry that also incorporates radiobiological modeling. Such sophisticated dosimetry techniques are still in the research investigation phase. Given the attendant logistical and financial costs, a demonstrated improvement in patient care will be a prerequisite for the adoption of such highly-patient specific internal dosimetry methods. PMID:18662554

  2. Acoustic 3D imaging of dental structures

    SciTech Connect

    Lewis, D.K.; Hume, W.R.; Douglass, G.D.

    1997-02-01

    Our goals for the first year of this three dimensional electodynamic imaging project was to determine how to combine flexible, individual addressable; preprocessing of array source signals; spectral extrapolation or received signals; acoustic tomography codes; and acoustic propagation modeling code. We investigated flexible, individually addressable acoustic array material to find the best match in power, sensitivity and cost and settled on PVDF sheet arrays and 3-1 composite material.

  3. Constraining 3D Process Sedimentological Models to Geophysical Data Using Image Quilting

    NASA Astrophysics Data System (ADS)

    Tahmasebi, P.; Da Pra, A.; Pontiggia, M.; Caers, J.

    2014-12-01

    3D process geological models, whether for carbonate or sedimentological systems, have been proposed for modeling realistic subsurface heterogeneity. The problem with such forward process models is that they are not constrained to any subsurface data whether to wells or geophysical surveys. We propose a new method for realistic geological modeling of complex heterogeneity by hybridizing 3D process modeling of geological deposition with conditioning by means of a novel multiple-point geostatistics (MPS) technique termed image quilting (IQ). Image quilting is a pattern-based techniques that stiches together patterns extracted from training images to generate stochastic realizations that look like the training image. In this paper, we illustrate how 3D process model realizations can be used as training images in image quilting. To constrain the realization to seismic data we first interpret each facies in the geophysical data. These interpretation, while overly smooth and not reflecting finer scale variation are used as auxiliary variables in the generation of the image quilting realizations. To condition to well data, we first perform a kriging of the well data to generate a kriging map and kriging variance. The kriging map is used as additional auxiliary variable while the kriging variance is used as a weight given to the kriging derived auxiliary variable. We present an application to a giant offshore reservoir. Starting from seismic advanced attribute analysis and sedimentological interpretation, we build the 3D sedimentological process based model and use it as non-stationary training image for conditional image quilting.

  4. MR image denoising method for brain surface 3D modeling

    NASA Astrophysics Data System (ADS)

    Zhao, De-xin; Liu, Peng-jie; Zhang, De-gan

    2014-11-01

    Three-dimensional (3D) modeling of medical images is a critical part of surgical simulation. In this paper, we focus on the magnetic resonance (MR) images denoising for brain modeling reconstruction, and exploit a practical solution. We attempt to remove the noise existing in the MR imaging signal and preserve the image characteristics. A wavelet-based adaptive curve shrinkage function is presented in spherical coordinates system. The comparative experiments show that the denoising method can preserve better image details and enhance the coefficients of contours. Using these denoised images, the brain 3D visualization is given through surface triangle mesh model, which demonstrates the effectiveness of the proposed method.

  5. 3D-spectral domain computational imaging

    NASA Astrophysics Data System (ADS)

    Anderson, Trevor; Segref, Armin; Frisken, Grant; Ferra, Herman; Lorenser, Dirk; Frisken, Steven

    2016-03-01

    We present a proof-of-concept experiment utilizing a novel "snap-shot" spectral domain OCT technique that captures a phase coherent volume in a single frame. The sample is illuminated with a collimated beam of 75 μm diameter and the back-reflected light is analyzed by a 2-D matrix of spectral interferograms. A key challenge that is addressed is simultaneously maintaining lateral and spectral phase coherence over the imaged volume in the presence of sample motion. Digital focusing is demonstrated for 5.0 μm lateral resolution over an 800 μm axial range.

  6. Poor boy 3D seismic effort yields South Central Kentucky discovery

    SciTech Connect

    Hanratty, M.

    1996-11-04

    Clinton County, Ky., is on the eastern flank of the Cincinnati arch and the western edge of the Appalachian basin and the Pine Mountain overthrust. Clinton County has long been known for high volume fractured carbonate wells. The discovery of these fractured reservoir, unfortunately, has historically been serendipitous. The author currently uses 2D seismic and satellite imagery to design 3D high resolution seismic shoots. This method has proven to be the most efficient and is the core of his program. The paper describes exploration methods, seismic acquisition, well data base, and seismic interpretation.

  7. Analysis of Paleokarst Sinkholes in the Arkoma Basin using 3-D Seismic

    NASA Astrophysics Data System (ADS)

    Kumbalek, Michael

    Paleokarst features are important to understand, both with regards to research geologists and to the petroleum industry. In terms of geology, understanding paleokarst features can yield more information about the depositional and surface environments of past times, and how diagenetic alteration affected the environment during the formation of karst features. In the petroleum industry, paleokarst features can have positive or negative consequence resulting in a potential reservoir with enhanced porosity due to the paleokarst features, or as a geo-hazard to prepare for or avoid when drilling. Inspired by issues faced when drilling in the Ft. Worth basin, this study utilizes multiple 3-D seismic surveys and subsurface well control to map paleokarsts within the Viola Limestone in the Arkoma Basin. Calculated seismic attribute volumes used to identify paleokarst sinkholes within the Viola Group include coherency and curvature attributes. ImageJ software was used to aid in counting and measuring paleokarst sinkholes identified using seismic mapping, coherency, and curvature attribute volumes. In addition to mapping, a cumulative distribution plot was produced from the diameters of the seismically mapped paleokarst sinkholes, allowing for an estimate to be made as to what the total amount of paleokarst sinkholes are within the study area. The methods detailed in this study proved to be effective in mapping and analyzing paleokarst sinkholes within the Viola Group. The paleokarst sinkholes mapped were determined to have been formed on the outer edge of the Southern Oklahoma aulacogen, as a result of the Sylvan/Viola unconformity. In addition to this, it has been determined that these paleokarst sinkholes are linked in formation to visually similar paleokarst sinkholes located in the Ellenburger Group in the Fort Worth Basin.

  8. Morphometrics, 3D Imaging, and Craniofacial Development.

    PubMed

    Hallgrimsson, Benedikt; Percival, Christopher J; Green, Rebecca; Young, Nathan M; Mio, Washington; Marcucio, Ralph

    2015-01-01

    Recent studies have shown how volumetric imaging and morphometrics can add significantly to our understanding of morphogenesis, the developmental basis for variation, and the etiology of structural birth defects. On the other hand, the complex questions and diverse imaging data in developmental biology present morphometrics with more complex challenges than applications in virtually any other field. Meeting these challenges is necessary in order to understand the mechanistic basis for variation in complex morphologies. This chapter reviews the methods and theory that enable the application of modern landmark-based morphometrics to developmental biology and craniofacial development, in particular. We discuss the theoretical foundations of morphometrics as applied to development and review the basic approaches to the quantification of morphology. Focusing on geometric morphometrics, we discuss the principal statistical methods for quantifying and comparing morphological variation and covariation structure within and among groups. Finally, we discuss the future directions for morphometrics in developmental biology that will be required for approaches that enable quantitative integration across the genotype-phenotype map. PMID:26589938

  9. 3D quantitative phase imaging of neural networks using WDT

    NASA Astrophysics Data System (ADS)

    Kim, Taewoo; Liu, S. C.; Iyer, Raj; Gillette, Martha U.; Popescu, Gabriel

    2015-03-01

    White-light diffraction tomography (WDT) is a recently developed 3D imaging technique based on a quantitative phase imaging system called spatial light interference microscopy (SLIM). The technique has achieved a sub-micron resolution in all three directions with high sensitivity granted by the low-coherence of a white-light source. Demonstrations of the technique on single cell imaging have been presented previously; however, imaging on any larger sample, including a cluster of cells, has not been demonstrated using the technique. Neurons in an animal body form a highly complex and spatially organized 3D structure, which can be characterized by neuronal networks or circuits. Currently, the most common method of studying the 3D structure of neuron networks is by using a confocal fluorescence microscope, which requires fluorescence tagging with either transient membrane dyes or after fixation of the cells. Therefore, studies on neurons are often limited to samples that are chemically treated and/or dead. WDT presents a solution for imaging live neuron networks with a high spatial and temporal resolution, because it is a 3D imaging method that is label-free and non-invasive. Using this method, a mouse or rat hippocampal neuron culture and a mouse dorsal root ganglion (DRG) neuron culture have been imaged in order to see the extension of processes between the cells in 3D. Furthermore, the tomogram is compared with a confocal fluorescence image in order to investigate the 3D structure at synapses.

  10. Simulation of 3D Seismic Wave Propagation with Volcano Topography

    NASA Astrophysics Data System (ADS)

    Ripperger, J.; Igel, H.; Wassermann, J.

    2001-12-01

    We investigate the possibilities of using three-dimensional finite difference (FD) methods for numerical simulation of the seismic wave field at active volcanoes. We put special emphasis on the implementation of the boundary conditions for free surface topography. We compare two different approaches to solve the free surface boundary conditions. The algorithms are implemented on parallel hardware and have been tested for correctness and stability. We apply them to smooth artificial topographies and to the real topography of Mount Merapi, Indonesia. We conclude, that grid stretching type methods (e.g. Hestholm & Ruud, 1994) are not well suited for realistic volcano topography as they tend to become unstable for large topographic gradients. The representation of topography through staircase shaped grids (Ohminato & Chouet, 1997) results in stable calculations, while demanding very fine gridding. The simulations show the effects of a three-dimensional surface topography on elastic wave propagation. Ground motion at the surface is severely affected by topography. If neglected, this may jeopardize attempts to determine source location by analyzing particle motion. Numerical studies like this can help to understand wave propagation phenomena observed on field recordings in volcano seismology. Future studies will aim at separating the wave effects of internal scattering, topography and sources (tremors, tectonic events, pyroclastic flows).

  11. Seismic 3D modelling of VHMS deposits: case studies from Pyhäsalmi and Vihanti, Finland

    NASA Astrophysics Data System (ADS)

    Heinonen, Suvi; Heikkinen, Pekka; Kukkonen, Ilmo; Snyder, David

    2013-04-01

    from the known deposit of Pyhäsalmi. Heterogeneous geological surroundings and an unfavourable shape of the ore deposit mask the seismic signal originating from the ore-host rock contact. Based on these experiences, hardrock seismic exploration is most efficiently done through geological 3D-modeling in which determination of a favourable geological setting for ore is used to target drill holes instead of only hunting bright spots. In both study areas seismic data has increased the knowledge about areal geological structures, continuation of ore-hosting lithologies in depth and also helped to understand better the tectonic evolution of the area. These studies show that 3D modelling of seismic profiles is efficient in improving geological understanding of the structures controlling the ore deposits in thus guiding exploration efforts.

  12. Accommodation response measurements for integral 3D image

    NASA Astrophysics Data System (ADS)

    Hiura, H.; Mishina, T.; Arai, J.; Iwadate, Y.

    2014-03-01

    We measured accommodation responses under integral photography (IP), binocular stereoscopic, and real object display conditions, and viewing conditions of binocular and monocular viewing conditions. The equipment we used was an optometric device and a 3D display. We developed the 3D display for IP and binocular stereoscopic images that comprises a high-resolution liquid crystal display (LCD) and a high-density lens array. The LCD has a resolution of 468 dpi and a diagonal size of 4.8 inches. The high-density lens array comprises 106 x 69 micro lenses that have a focal length of 3 mm and diameter of 1 mm. The lenses are arranged in a honeycomb pattern. The 3D display was positioned 60 cm from an observer under IP and binocular stereoscopic display conditions. The target was presented at eight depth positions relative to the 3D display: 15, 10, and 5 cm in front of the 3D display, on the 3D display panel, and 5, 10, 15 and 30 cm behind the 3D display under the IP and binocular stereoscopic display conditions. Under the real object display condition, the target was displayed on the 3D display panel, and the 3D display was placed at the eight positions. The results suggest that the IP image induced more natural accommodation responses compared to the binocular stereoscopic image. The accommodation responses of the IP image were weaker than those of a real object; however, they showed a similar tendency with those of the real object under the two viewing conditions. Therefore, IP can induce accommodation to the depth positions of 3D images.

  13. Image based 3D city modeling : Comparative study

    NASA Astrophysics Data System (ADS)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2014-06-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  14. Understanding North Texas Seismicity: A Joint Analysis of Seismic Data and 3D Pore Pressure Modeling

    NASA Astrophysics Data System (ADS)

    DeShon, H. R.; Hornbach, M. J.; Ellsworth, W. L.; Oldham, H. R.; Hayward, C.; Stump, B. W.; Frohlich, C.; Olson, J. E.; Luetgert, J. H.

    2014-12-01

    In November 2013, a series of earthquakes began along a mapped ancient fault system near Azle, Texas. The Azle events are the third felt earthquake sequence in the Fort Worth (Barnett Shale) Basin since 2008, and several production and injection wells in the area are drilled to depths near the recent seismic activity. Understanding if and/or how injection and removal of fluids in the crystalline crust reactivates faults have important implications for seismology, the energy industry, and society. We assessed whether the Azle earthquakes were induced using a joint analysis of the earthquake data, subsurface geology and fault structure, and 3D pore pressure modeling. Using a 12-station temporary seismic deployment, we have recorded and located >300 events large enough to be recorded on multiple stations and 1000s of events during periods of swarm activity. High-resolution locations and focal mechanisms indicate that events occurred on NE-SW trending, steeply dipping normal faults associated with the southern end of the Newark East Fault Zone with hypocenters between 2-8 km depth. We considered multiple causes that might have changed stress along this system. Earthquakes resulting from natural processes, though perhaps unlikely in this historically inactive region, can be neither ruled out nor confirmed due to lack of information on the natural stress state of these faults. Analysis of lake and groundwater variations near Azle showed that no significant stress changes occurred prior to or during the earthquake sequence. In contrast, analysis of pore-pressure models shows that the combination of formation water production and wastewater injection near the fault could have caused pressure increases that induced earthquakes on near-critically stressed faults.

  15. Seismic source inversion using Green's reciprocity and a 3-D structural model for the Japanese Islands

    NASA Astrophysics Data System (ADS)

    Simutė, S.; Fichtner, A.

    2015-12-01

    We present a feasibility study for seismic source inversions using a 3-D velocity model for the Japanese Islands. The approach involves numerically calculating 3-D Green's tensors, which is made efficient by exploiting Green's reciprocity. The rationale for 3-D seismic source inversion has several aspects. For structurally complex regions, such as the Japan area, it is necessary to account for 3-D Earth heterogeneities to prevent unknown structure polluting source solutions. In addition, earthquake source characterisation can serve as a means to delineate existing faults. Source parameters obtained for more realistic Earth models can then facilitate improvements in seismic tomography and early warning systems, which are particularly important for seismically active areas, such as Japan. We have created a database of numerically computed 3-D Green's reciprocals for a 40°× 40°× 600 km size area around the Japanese Archipelago for >150 broadband stations. For this we used a regional 3-D velocity model, recently obtained from full waveform inversion. The model includes attenuation and radial anisotropy and explains seismic waveform data for periods between 10 - 80 s generally well. The aim is to perform source inversions using the database of 3-D Green's tensors. As preliminary steps, we present initial concepts to address issues that are at the basis of our approach. We first investigate to which extent Green's reciprocity works in a discrete domain. Considering substantial amounts of computed Green's tensors we address storage requirements and file formatting. We discuss the importance of the initial source model, as an intelligent choice can substantially reduce the search volume. Possibilities to perform a Bayesian inversion and ways to move to finite source inversion are also explored.

  16. Optical 3D watermark based digital image watermarking for telemedicine

    NASA Astrophysics Data System (ADS)

    Li, Xiao Wei; Kim, Seok Tae

    2013-12-01

    Region of interest (ROI) of a medical image is an area including important diagnostic information and must be stored without any distortion. This algorithm for application of watermarking technique for non-ROI of the medical image preserving ROI. The paper presents a 3D watermark based medical image watermarking scheme. In this paper, a 3D watermark object is first decomposed into 2D elemental image array (EIA) by a lenslet array, and then the 2D elemental image array data is embedded into the host image. The watermark extraction process is an inverse process of embedding. The extracted EIA through the computational integral imaging reconstruction (CIIR) technique, the 3D watermark can be reconstructed. Because the EIA is composed of a number of elemental images possesses their own perspectives of a 3D watermark object. Even though the embedded watermark data badly damaged, the 3D virtual watermark can be successfully reconstructed. Furthermore, using CAT with various rule number parameters, it is possible to get many channels for embedding. So our method can recover the weak point having only one transform plane in traditional watermarking methods. The effectiveness of the proposed watermarking scheme is demonstrated with the aid of experimental results.

  17. EISCAT Aperture Synthesis Imaging (EASI _3D) for the EISCAT_3D Project

    NASA Astrophysics Data System (ADS)

    La Hoz, Cesar; Belyey, Vasyl

    2012-07-01

    Aperture Synthesis Imaging Radar (ASIR) is one of the technologies adopted by the EISCAT_3D project to endow it with imaging capabilities in 3-dimensions that includes sub-beam resolution. Complemented by pulse compression, it will provide 3-dimensional images of certain types of incoherent scatter radar targets resolved to about 100 metres at 100 km range, depending on the signal-to-noise ratio. This ability will open new research opportunities to map small structures associated with non-homogeneous, unstable processes such as aurora, summer and winter polar radar echoes (PMSE and PMWE), Natural Enhanced Ion Acoustic Lines (NEIALs), structures excited by HF ionospheric heating, meteors, space debris, and others. The underlying physico-mathematical principles of the technique are the same as the technique employed in radioastronomy to image stellar objects; both require sophisticated inversion techniques to obtain reliable images.

  18. An Investigation of 3D Seismic Deep Basement Events in Osage County, Oklahoma

    NASA Astrophysics Data System (ADS)

    Liner, Kevin Matthew

    Deep basement events seen in 3D seismic surveys located in Osage County, Oklahoma can be observed and may have affect overlying sedimentary formations. The 3D surveys used in this study are on the Chautauqua platform about fifty miles northwest of Tulsa, Oklahoma. Stratigraphy of the work area spans base of the Permian to Precambrian formations, with basement depth averaging around 5000 ft in the area of the 3D seismic surveys. Cores spanning Precambrian to Pennsylvanian were examined in the area of the 3D seismic surveys. Hydrothermal minerals were observed in Mississippian age cores. The basement events where tracked using OpendTect with strike and dip measurements taken. Precambrian basement rock outcrops in Mays County near the town of Spavinaw, Oklahoma. Granite paleotopograhic highs (referred to as the Tulsa Mountains) can be seen on a structural contour map of the basement on the eastern side of Osage County. The goal is to study the Precambrian basement using 3D seismic, core samples, and well logs to identify and track basement events through the granite basement and into the overlying sedimentary section.

  19. New 3D seismicity maps using chromo-stereoscopy with two alternative freewares

    NASA Astrophysics Data System (ADS)

    Okamoto, Y.

    2011-12-01

    Seismicity maps play a key role in an introduction of geosciences studies or outreach programs. Various techniques are used in order to show earthquakes in a three dimensional field. To use "chromo-stereoscopy" is our simple and easier-making solution. The Chroma Depth 3D Glasses are employed for this purpose. The glasses consist of two transparent blazed grating films covered with a paper holder and cost a little (1 US$). Looking through these glasses, the colored chart turns into three dimensional perspective due to the mechanism that the color codes make a depth dimension with dispersion. We use two complementary freewares to make maps, the GMT (Generic Mapping Tools, Wessel and Smith.1988) and the POV-Ray (Persistence of Vision Pty. Ltd. 2004). The two softwares have their own advantages; the GMT is specialized for map making with simple scripts, while the POV-Ray produces realistic 3D rendering images with more complicated scripts. The earthquakes are plotted with the rainbow color codes depending on their depths in a black background as printed or PC images. Therefore, the red colored shallow earthquakes are float in front and blue colored ones sink deeper. This effect is so amazing that the students who first wear these glasses are strongly moved and fascinated with this simple mechanism. The data used here are from JMA seismicity catalogue and USGS (ANSS) catalogue. The POV-Ray version needs coastline data, so we got them from the Coastline Extractor (NGDC) web site. Also, the POR-Ray has no function to draw lines in three dimensions, so we had to make some trials for showing them in relief. The main target of our map is "the Wadati-Beniof zone", in which the sub-ducting oceanic plate surface is fringed by deeper earthquakes colored yellow, green to blue. The active volcanic regions such as the Hawaii islands or the active fault regions such as the San Andreas Fault are also effective targets of our method. However, since their shallow complicated seismic

  20. Faster, higher quality volume visualization for 3D medical imaging

    NASA Astrophysics Data System (ADS)

    Kalvin, Alan D.; Laine, Andrew F.; Song, Ting

    2008-03-01

    The two major volume visualization methods used in biomedical applications are Maximum Intensity Projection (MIP) and Volume Rendering (VR), both of which involve the process of creating sets of 2D projections from 3D images. We have developed a new method for very fast, high-quality volume visualization of 3D biomedical images, based on the fact that the inverse of this process (transforming 2D projections into a 3D image) is essentially equivalent to tomographic image reconstruction. This new method uses the 2D projections acquired by the scanner, thereby obviating the need for the two computationally expensive steps currently required in the complete process of biomedical visualization, that is, (i) reconstructing the 3D image from 2D projection data, and (ii) computing the set of 2D projections from the reconstructed 3D image As well as improvements in computation speed, this method also results in improvements in visualization quality, and in the case of x-ray CT we can exploit this quality improvement to reduce radiation dosage. In this paper, demonstrate the benefits of developing biomedical visualization techniques by directly processing the sensor data acquired by body scanners, rather than by processing the image data reconstructed from the sensor data. We show results of using this approach for volume visualization for tomographic modalities, like x-ray CT, and as well as for MRI.

  1. Seismic reflection imaging at a Shallow Site

    SciTech Connect

    Milligan, P.; Rector, J.; Bainer, R.

    1997-01-01

    The objective of our studies was to determine the best seismic method to image these sediments, between the water table at 3 m depth to the basement at 35 m depth. Good cross-correlation between well logs and the seismic data was also desirable, and would facilitate the tracking of known lithological units away from the wells. For instance, known aquifer control boundaries may then be mapped out over the boundaries, and may be used in a joint inversion with reflectivity data and other non-seismic geophysical data to produce a 3-D image containing quantitative physical properties of the target area.

  2. Low Dose, Low Energy 3d Image Guidance during Radiotherapy

    NASA Astrophysics Data System (ADS)

    Moore, C. J.; Marchant, T.; Amer, A.; Sharrock, P.; Price, P.; Burton, D.

    2006-04-01

    Patient kilo-voltage X-ray cone beam volumetric imaging for radiotherapy was first demonstrated on an Elekta Synergy mega-voltage X-ray linear accelerator. Subsequently low dose, reduced profile reconstruction imaging was shown to be practical for 3D geometric setup registration to pre-treatment planning images without compromising registration accuracy. Reconstruction from X-ray profiles gathered between treatment beam deliveries was also introduced. The innovation of zonal cone beam imaging promises significantly reduced doses to patients and improved soft tissue contrast in the tumour target zone. These developments coincided with the first dynamic 3D monitoring of continuous body topology changes in patients, at the moment of irradiation, using a laser interferometer. They signal the arrival of low dose, low energy 3D image guidance during radiotherapy itself.

  3. An Integrated Multi-component Processing and Interpretation Framework for 3D Borehole Seismic Data

    SciTech Connect

    M. Karrenbach

    2004-10-15

    This report covers the April 2004-September 2004 time period. Work has been performed successfully on several tasks 1 through 16. Part of this work has been reported in 15418R03. Most of portions of these tasks have been executed independently. We progressed steadily and completed some of the sub-tasks, while others are still on going. We achieved the goals that we had set up in the task schedule. Reviewing the results of this work period indicates that our plan is solid and we did not encounter any unforeseen problems. The work plan will continue as scheduled. A midyear review will be presented in November or December 2004. Several independent tasks pursuant the statement of project objectives have been executed simultaneously and are still on-going. Use of real seismic test data is augmented by the creation a 3D ray tracing synthetic test data. We used the previously constructed 3D layered model and simulated data acquisition from a set of circular source locations at the surface of the model, while a close to vertical VSP well was used to capture the wave field data. The source pattern was optimized with respect to Fresnel zone width at the target depth. Multi-component particle displacements were recorded every 50 ft down with an array length of 4,000 ft. P-P as well as P-S reflections were specified in the resulting wave field. We ensured a large enough aperture with enough fine sampling to perform advanced processing, imaging and analysis tests in the future during this project. We constantly improved the interfacing of our software libraries with newly designed 3C display classes and mechanisms. We used the previously implemented 3C Work Bench tool as the primary prototyping tool. This work bench allows to load as well as manipulate and display data items in a flexible manner. We continued to demonstrate its basic functionality by loading source maps, horizons, seismic and velocity volumes, well logs into the tool, performing basic QC steps as is necessary

  4. 3D thermography imaging standardization technique for inflammation diagnosis

    NASA Astrophysics Data System (ADS)

    Ju, Xiangyang; Nebel, Jean-Christophe; Siebert, J. Paul

    2005-01-01

    We develop a 3D thermography imaging standardization technique to allow quantitative data analysis. Medical Digital Infrared Thermal Imaging is very sensitive and reliable mean of graphically mapping and display skin surface temperature. It allows doctors to visualise in colour and quantify temperature changes in skin surface. The spectrum of colours indicates both hot and cold responses which may co-exist if the pain associate with an inflammatory focus excites an increase in sympathetic activity. However, due to thermograph provides only qualitative diagnosis information, it has not gained acceptance in the medical and veterinary communities as a necessary or effective tool in inflammation and tumor detection. Here, our technique is based on the combination of visual 3D imaging technique and thermal imaging technique, which maps the 2D thermography images on to 3D anatomical model. Then we rectify the 3D thermogram into a view independent thermogram and conform it a standard shape template. The combination of these imaging facilities allows the generation of combined 3D and thermal data from which thermal signatures can be quantified.

  5. SNR analysis of 3D magnetic resonance tomosynthesis (MRT) imaging

    NASA Astrophysics Data System (ADS)

    Kim, Min-Oh; Kim, Dong-Hyun

    2012-03-01

    In conventional 3D Fourier transform (3DFT) MR imaging, signal-to-noise ratio (SNR) is governed by the well-known relationship of being proportional to the voxel size and square root of the imaging time. Here, we introduce an alternative 3D imaging approach, termed MRT (Magnetic Resonance Tomosynthesis), which can generate a set of tomographic MR images similar to multiple 2D projection images in x-ray. A multiple-oblique-view (MOV) pulse sequence is designed to acquire the tomography-like images used in tomosynthesis process and an iterative back-projection (IBP) reconstruction method is used to reconstruct 3D images. SNR analysis is performed and shows that resolution and SNR tradeoff is not governed as with typical 3DFT MR imaging case. The proposed method provides a higher SNR than the conventional 3D imaging method with a partial loss of slice-direction resolution. It is expected that this method can be useful for extremely low SNR cases.

  6. 3D gesture recognition from serial range image

    NASA Astrophysics Data System (ADS)

    Matsui, Yasuyuki; Miyasaka, Takeo; Hirose, Makoto; Araki, Kazuo

    2001-10-01

    In this research, the recognition of gesture in 3D space is examined by using serial range images obtained by a real-time 3D measurement system developed in our laboratory. Using this system, it is possible to obtain time sequences of range, intensity and color data for a moving object in real-time without assigning markers to the targets. At first, gestures are tracked in 2D space by calculating 2D flow vectors at each points using an ordinal optical flow estimation method, based on time sequences of the intensity data. Then, location of each point after 2D movement is detected on the x-y plane using thus obtained 2D flow vectors. Depth information of each point after movement is then obtained from the range data and 3D flow vectors are assigned to each point. Time sequences of thus obtained 3D flow vectors allow us to track the 3D movement of the target. So, based on time sequences of 3D flow vectors of the targets, it is possible to classify the movement of the targets using continuous DP matching technique. This tracking of 3D movement using time sequences of 3D flow vectors may be applicable for a robust gesture recognition system.

  7. A 3D surface imaging system for assessing human obesity

    NASA Astrophysics Data System (ADS)

    Xu, B.; Yu, W.; Yao, M.; Yao, X.; Li, Q.; Pepper, M. R.; Freeland-Graves, J. H.

    2009-08-01

    The increasing prevalence of obesity suggests a need to develop a convenient, reliable and economical tool for assessment of this condition. Three-dimensional (3D) body surface imaging has emerged as an exciting technology for estimation of body composition. This paper presents a new 3D body imaging system, which was designed for enhanced portability, affordability, and functionality. In this system, stereo vision technology was used to satisfy the requirements for a simple hardware setup and fast image acquisitions. The portability of the system was created via a two-stand configuration, and the accuracy of body volume measurements was improved by customizing stereo matching and surface reconstruction algorithms that target specific problems in 3D body imaging. Body measurement functions dedicated to body composition assessment also were developed. The overall performance of the system was evaluated in human subjects by comparison to other conventional anthropometric methods, as well as air displacement plethysmography, for body fat assessment.

  8. 3D Image Display Courses for Information Media Students.

    PubMed

    Yanaka, Kazuhisa; Yamanouchi, Toshiaki

    2016-01-01

    Three-dimensional displays are used extensively in movies and games. These displays are also essential in mixed reality, where virtual and real spaces overlap. Therefore, engineers and creators should be trained to master 3D display technologies. For this reason, the Department of Information Media at the Kanagawa Institute of Technology has launched two 3D image display courses specifically designed for students who aim to become information media engineers and creators. PMID:26960028

  9. Hybrid segmentation framework for 3D medical image analysis

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Metaxas, Dimitri N.

    2003-05-01

    Medical image segmentation is the process that defines the region of interest in the image volume. Classical segmentation methods such as region-based methods and boundary-based methods cannot make full use of the information provided by the image. In this paper we proposed a general hybrid framework for 3D medical image segmentation purposes. In our approach we combine the Gibbs Prior model, and the deformable model. First, Gibbs Prior models are applied onto each slice in a 3D medical image volume and the segmentation results are combined to a 3D binary masks of the object. Then we create a deformable mesh based on this 3D binary mask. The deformable model will be lead to the edge features in the volume with the help of image derived external forces. The deformable model segmentation result can be used to update the parameters for Gibbs Prior models. These methods will then work recursively to reach a global segmentation solution. The hybrid segmentation framework has been applied to images with the objective of lung, heart, colon, jaw, tumor, and brain. The experimental data includes MRI (T1, T2, PD), CT, X-ray, Ultra-Sound images. High quality results are achieved with relatively efficient time cost. We also did validation work using expert manual segmentation as the ground truth. The result shows that the hybrid segmentation may have further clinical use.

  10. A Geo-referenced 3D model of the Juan de Fuca Slab and associated seismicity

    USGS Publications Warehouse

    Blair, J.L.; McCrory, P.A.; Oppenheimer, D.H.; Waldhauser, F.

    2011-01-01

    We present a Geographic Information System (GIS) of a new 3-dimensional (3D) model of the subducted Juan de Fuca Plate beneath western North America and associated seismicity of the Cascadia subduction system. The geo-referenced 3D model was constructed from weighted control points that integrate depth information from hypocenter locations and regional seismic velocity studies. We used the 3D model to differentiate earthquakes that occur above the Juan de Fuca Plate surface from earthquakes that occur below the plate surface. This GIS project of the Cascadia subduction system supersedes the one previously published by McCrory and others (2006). Our new slab model updates the model with new constraints. The most significant updates to the model include: (1) weighted control points to incorporate spatial uncertainty, (2) an additional gridded slab surface based on the Generic Mapping Tools (GMT) Surface program which constructs surfaces based on splines in tension (see expanded description below), (3) double-differenced hypocenter locations in northern California to better constrain slab location there, and (4) revised slab shape based on new hypocenter profiles that incorporate routine depth uncertainties as well as data from new seismic-reflection and seismic-refraction studies. We also provide a 3D fly-through animation of the model for use as a visualization tool.

  11. Ultra-high-resolution marine 2D-3D seismic investigation of the Liman Tepe/Karantina Island archaeological site (Urla/Turkey)

    NASA Astrophysics Data System (ADS)

    Müller, C.; Woelz, S.; Ersoy, Y.; Boyce, J.; Jokisch, T.; Wendt, G.; Rabbel, W.

    2009-05-01

    2D and 3D high-resolution seismic investigations were performed on submerged coastal archaeological sites at Iskele and near to Karantina Island in the Bay of Izmir in western Turkey. Tectonic subsidence of the coastline has submerged a number of archaeological features associated with an important Early Bronze Archaic settlement (Liman Tepe) and the classical Ionian city of Clazomenae. Seismic surveys were focused on imaging of an Archaic harbour structure and other submerged Hellenistic and Roman architectural features. Seismic data were acquired with the SEAMAP-3D ultra-high-resolution 3D marine seismic acquisition system developed for detailed archaeological site investigation. A 2D reconnaissance survey was performed over a 2 km 2 area around Karantina Island to evaluate the seismic penetrability and to locate sites for further 3D investigation. This survey predominantly revealed marine sediment layers covering the local bedrock, which is characterized by scattering of seismic energy showing its rocky nature. Two ultra-high-resolution 3D seismic surveys were performed. The first covered a 350 m × 30 m area in the modern harbour targeting a prominent Archaic harbour structure. The second was acquired across a 120 m × 40 m area on the southeast shore of the Karantina Island close to a Roman architectural feature. The 3D surveys were acquired with nominal line spacings of 1 m, using a 8 × 4 pseudo-rigid hydrophone array and a Boomer source firing at 3 Hz shot frequency. Automated processing of the seismic data using a portable Linux cluster provided stacked 3D seismic volumes with 25 cm × 25 cm bin size on-site. The 3D seismic survey of the harbour clearly imaged the submerged Archaic structure and the underlying sediment sequence. The seismic time slices reveal two seismic anomalies (2-3 m in diameter) in the harbour basin sediments. The 3D surveys southeast of Karantina identified a thicker marine sediment sequence overlying steeply dipping bedrock

  12. 2D/3D Image Registration using Regression Learning

    PubMed Central

    Chou, Chen-Rui; Frederick, Brandon; Mageras, Gig; Chang, Sha; Pizer, Stephen

    2013-01-01

    In computer vision and image analysis, image registration between 2D projections and a 3D image that achieves high accuracy and near real-time computation is challenging. In this paper, we propose a novel method that can rapidly detect an object’s 3D rigid motion or deformation from a 2D projection image or a small set thereof. The method is called CLARET (Correction via Limited-Angle Residues in External Beam Therapy) and consists of two stages: registration preceded by shape space and regression learning. In the registration stage, linear operators are used to iteratively estimate the motion/deformation parameters based on the current intensity residue between the target projec-tion(s) and the digitally reconstructed radiograph(s) (DRRs) of the estimated 3D image. The method determines the linear operators via a two-step learning process. First, it builds a low-order parametric model of the image region’s motion/deformation shape space from its prior 3D images. Second, using learning-time samples produced from the 3D images, it formulates the relationships between the model parameters and the co-varying 2D projection intensity residues by multi-scale linear regressions. The calculated multi-scale regression matrices yield the coarse-to-fine linear operators used in estimating the model parameters from the 2D projection intensity residues in the registration. The method’s application to Image-guided Radiation Therapy (IGRT) requires only a few seconds and yields good results in localizing a tumor under rigid motion in the head and neck and under respiratory deformation in the lung, using one treatment-time imaging 2D projection or a small set thereof. PMID:24058278

  13. 3-D Terahertz Synthetic-Aperture Imaging and Spectroscopy

    NASA Astrophysics Data System (ADS)

    Henry, Samuel C.

    Terahertz (THz) wavelengths have attracted recent interest in multiple disciplines within engineering and science. Situated between the infrared and the microwave region of the electromagnetic spectrum, THz energy can propagate through non-polar materials such as clothing or packaging layers. Moreover, many chemical compounds, including explosives and many drugs, reveal strong absorption signatures in the THz range. For these reasons, THz wavelengths have great potential for non-destructive evaluation and explosive detection. Three-dimensional (3-D) reflection imaging with considerable depth resolution is also possible using pulsed THz systems. While THz imaging (especially 3-D) systems typically operate in transmission mode, reflection offers the most practical configuration for standoff detection, especially for objects with high water content (like human tissue) which are opaque at THz frequencies. In this research, reflection-based THz synthetic-aperture (SA) imaging is investigated as a potential imaging solution. THz SA imaging results presented in this dissertation are unique in that a 2-D planar synthetic array was used to generate a 3-D image without relying on a narrow time-window for depth isolation cite [Shen 2005]. Novel THz chemical detection techniques are developed and combined with broadband THz SA capabilities to provide concurrent 3-D spectral imaging. All algorithms are tested with various objects and pressed pellets using a pulsed THz time-domain system in the Northwest Electromagnetics and Acoustics Research Laboratory (NEAR-Lab).

  14. Identifying High Potential Well Targets with 3D Seismic and Mineralogy

    SciTech Connect

    Mellors, R. J.

    2015-10-30

    Seismic reflection the primary tool used in petroleum exploration and production, but use in geothermal exploration is less standard, in part due to cost but also due to the challenges in identifying the highly-permeable zones essential for economic hydrothermal systems [e.g. Louie et al., 2011; Majer, 2003]. Newer technology, such as wireless sensors and low-cost high performance computing, has helped reduce the cost and effort needed to conduct 3D surveys. The second difficulty, identifying permeable zones, has been less tractable so far. Here we report on the use of seismic attributes from a 3D seismic survey to identify and map permeable zones in a hydrothermal area.

  15. Computerized analysis of pelvic incidence from 3D images

    NASA Astrophysics Data System (ADS)

    Vrtovec, Tomaž; Janssen, Michiel M. A.; Pernuš, Franjo; Castelein, René M.; Viergever, Max A.

    2012-02-01

    The sagittal alignment of the pelvis can be evaluated by the angle of pelvic incidence (PI), which is constant for an arbitrary subject position and orientation and can be therefore compared among subjects in standing, sitting or supine position. In this study, PI was measured from three-dimensional (3D) computed tomography (CT) images of normal subjects that were acquired in supine position. A novel computerized method, based on image processing techniques, was developed to automatically determine the anatomical references required to measure PI, i.e. the centers of the femoral heads in 3D, and the center and inclination of the sacral endplate in 3D. Multiplanar image reformation was applied to obtain perfect sagittal views with all anatomical structures completely in line with the hip axis, from which PI was calculated. The resulting PI (mean+/-standard deviation) was equal to 46.6°+/-9.2° for male subjects (N = 189), 47.6°+/-10.7° for female subjects (N = 181), and 47.1°+/-10.0° for all subjects (N = 370). The obtained measurements of PI from 3D images were not biased by acquisition projection or structure orientation, because all anatomical structures were completely in line with the hip axis. The performed measurements in 3D therefore represent PI according to the actual geometrical relationships among anatomical structures of the sacrum, pelvis and hips, as observed from the perfect sagittal views.

  16. Single 3D cell segmentation from optical CT microscope images

    NASA Astrophysics Data System (ADS)

    Xie, Yiting; Reeves, Anthony P.

    2014-03-01

    The automated segmentation of the nucleus and cytoplasm regions in 3D optical CT microscope images has been achieved with two methods, a global threshold gradient based approach and a graph-cut approach. For the first method, the first two peaks of a gradient figure of merit curve are selected as the thresholds for cytoplasm and nucleus segmentation. The second method applies a graph-cut segmentation twice: the first identifies the nucleus region and the second identifies the cytoplasm region. Image segmentation of single cells is important for automated disease diagnostic systems. The segmentation methods were evaluated with 200 3D images consisting of 40 samples of 5 different cell types. The cell types consisted of columnar, macrophage, metaplastic and squamous human cells and cultured A549 cancer cells. The segmented cells were compared with both 2D and 3D reference images and the quality of segmentation was determined by the Dice Similarity Coefficient (DSC). In general, the graph-cut method had a superior performance to the gradient-based method. The graph-cut method achieved an average DSC of 86% and 72% for nucleus and cytoplasm segmentations respectively for the 2D reference images and 83% and 75% for the 3D reference images. The gradient method achieved an average DSC of 72% and 51% for nucleus and cytoplasm segmentation for the 2D reference images and 71% and 51% for the 3D reference images. The DSC of cytoplasm segmentation was significantly lower than for the nucleus since the cytoplasm was not differentiated as well by image intensity from the background.

  17. AUTOMATING SHALLOW SEISMIC IMAGING

    SciTech Connect

    Steeples, Don W.

    2003-09-14

    The current project is a continuation of an effort to develop ultrashallow seismic imaging as a cost-effective method potentially applicable to DOE facilities. The objective of the present research is to develop and demonstrate the use of a cost-effective, automated method of conducting shallow seismic surveys, an approach that represents a significant departure from conventional seismic-survey field procedures. Initial testing of a mechanical geophone-planting device suggests that large numbers of geophones can be placed both quickly and automatically. The development of such a device could make the application of SSR considerably more efficient and less expensive. The imaging results obtained using automated seismic methods will be compared with results obtained using classical seismic techniques. Although this research falls primarily into the field of seismology, for comparison and quality-control purposes, some GPR data will be collected as well. In the final year of th e research, demonstration surveys at one or more DOE facilities will be performed. An automated geophone-planting device of the type under development would not necessarily be limited to the use of shallow seismic reflection methods; it also would be capable of collecting data for seismic-refraction and possibly for surface-wave studies. Another element of our research plan involves monitoring the cone of depression of a pumping well that is being used as a proxy site for fluid-flow at a contaminated site. Our next data set will be collected at a well site where drawdown equilibrium has been reached. Noninvasive, in-situ methods such as placing geophones automatically and using near-surface seismic methods to identify and characterize the hydrologic flow regimes at contaminated sites support the prospect of developing effective, cost-conscious cleanup strategies for DOE and others.

  18. Integrated optical 3D digital imaging based on DSP scheme

    NASA Astrophysics Data System (ADS)

    Wang, Xiaodong; Peng, Xiang; Gao, Bruce Z.

    2008-03-01

    We present a scheme of integrated optical 3-D digital imaging (IO3DI) based on digital signal processor (DSP), which can acquire range images independently without PC support. This scheme is based on a parallel hardware structure with aid of DSP and field programmable gate array (FPGA) to realize 3-D imaging. In this integrated scheme of 3-D imaging, the phase measurement profilometry is adopted. To realize the pipeline processing of the fringe projection, image acquisition and fringe pattern analysis, we present a multi-threads application program that is developed under the environment of DSP/BIOS RTOS (real-time operating system). Since RTOS provides a preemptive kernel and powerful configuration tool, with which we are able to achieve a real-time scheduling and synchronization. To accelerate automatic fringe analysis and phase unwrapping, we make use of the technique of software optimization. The proposed scheme can reach a performance of 39.5 f/s (frames per second), so it may well fit into real-time fringe-pattern analysis and can implement fast 3-D imaging. Experiment results are also presented to show the validity of proposed scheme.

  19. Advancing New 3D Seismic Interpretation Methods for Exploration and Development of Fractured Tight Gas Reservoirs

    SciTech Connect

    James Reeves

    2005-01-31

    In a study funded by the U.S. Department of Energy and GeoSpectrum, Inc., new P-wave 3D seismic interpretation methods to characterize fractured gas reservoirs are developed. A data driven exploratory approach is used to determine empirical relationships for reservoir properties. Fractures are predicted using seismic lineament mapping through a series of horizon and time slices in the reservoir zone. A seismic lineament is a linear feature seen in a slice through the seismic volume that has negligible vertical offset. We interpret that in regions of high seismic lineament density there is a greater likelihood of fractured reservoir. Seismic AVO attributes are developed to map brittle reservoir rock (low clay) and gas content. Brittle rocks are interpreted to be more fractured when seismic lineaments are present. The most important attribute developed in this study is the gas sensitive phase gradient (a new AVO attribute), as reservoir fractures may provide a plumbing system for both water and gas. Success is obtained when economic gas and oil discoveries are found. In a gas field previously plagued with poor drilling results, four new wells were spotted using the new methodology and recently drilled. The wells have estimated best of 12-months production indicators of 2106, 1652, 941, and 227 MCFGPD. The latter well was drilled in a region of swarming seismic lineaments but has poor gas sensitive phase gradient (AVO) and clay volume attributes. GeoSpectrum advised the unit operators that this location did not appear to have significant Lower Dakota gas before the well was drilled. The other three wells are considered good wells in this part of the basin and among the best wells in the area. These new drilling results have nearly doubled the gas production and the value of the field. The interpretation method is ready for commercialization and gas exploration and development. The new technology is adaptable to conventional lower cost 3D seismic surveys.

  20. The 3D crustal structure of Northeastern Tibetan area from seismic tomography

    NASA Astrophysics Data System (ADS)

    Sun, Anhui

    2015-04-01

    The Northeastern Tibetan region is located in the border area of three sub-plates in China, i.e. the Tibetan plateau, North China block and Xinjiang block. Effected simultaneously by the extrusion driven by the India-Eurasia plat collision and the blockage of the Ordos basin, this area has complex geology, strong tectonics activities and suffered from several large historic earthquakes, such as the Haiyuan earthquake (M8.6) in 1920, the Gulang earthquake (M8.0) in 1927. To enhance our understanding of the crustal structure and the interaction between different tectonic blocks of this region, we conduct a three-dimensional (3D) tomographic study by using the arrival time date recorded by regional seismic network. We used 101101 P and 103313 S wave arrival times from 11650 local earthquakes during 1970 to 2013 recorded by 154 permanent seismic stations of the local Seismic Network, installed over five provinces in China, i.e. Gansu, Ningxia, Qinghai, Shanxi, Neimenggu. We first established a 1D primary crustal model from LITHO1.0, an updated crust and lithospheric model of the Earth by weighted averaging. To better performer ray tracing, our inversion involved three discontinuities (including the Moho) with depth variation over the mantle derived from LITHO1.0. Detailed three-dimensional seismic velocity (Vp and Vs) structures of the crust of the Northeastern Tibetan are determined with a horizontal resolution of about 35 km and a depth resolution of 6-20 km. The Poisson's ratio (σ) structure was also estimated after obtained Vp and Vs structures. We detected low-velocity anomalies in the lower crust and relative high-velocity anomalies in the upper crust beneath the Longmenshan faults zone, which are in good agreement with the results of most previous geophysical studies. Our results revealed clear different velocity variation beneath both sides of different tectonic blocks. In addition, we found the correlation between our tomographic result and previous

  1. Reservoir lithofacies analysis using 3D seismic data in dissimilarity space

    NASA Astrophysics Data System (ADS)

    Bagheri, M.; Riahi, M. A.; Hashemi, H.

    2013-06-01

    Seismic data interpretation is one of the most important steps in exploration seismology. Seismic facies analysis (SFA) with emphasis on lithofacies can be used to extract more information about structures and geology, which results in seismic interpretation enhancement. Facies analysis is based on unsupervised and supervised classification using seismic attributes. In this paper, supervised classification by a support vector machine using well logs and seismic attributes is applied. Dissimilarity as a new measuring space is employed, after which classification is carried out. Often, SFA is carried out in a feature space in which each dimension stands as a seismic attribute. Different facies show lots of class overlap in the feature space; hence, high classification error values are reported. Therefore, decreasing class overlap before classification is a necessary step to be targeted. To achieve this goal, a dissimilarity space is initially created. As a result of the definition of the new space, the class overlap between objects (seismic samples) is reduced and hence the classification can be done reliably. This strategy causes an increase in the accuracy of classification, and a more trustworthy lithofacies analysis is attained. For applying this method, 3D seismic data from an oil field in Iran were selected and the results obtained by a support vector classifier (SVC) in dissimilarity space are presented, discussed and compared with the SVC applied in conventional feature space.

  2. Traveltime computation and imaging from rugged topography in 3D TTI media

    NASA Astrophysics Data System (ADS)

    Liu, Shaoyong; Wang, Huazhong; Yang, Qinyong; Fang, Wubao

    2014-02-01

    Foothill areas with rugged topography are of great potential for oil and gas seismic exploration, but subsurface imaging in these areas is very challenging. Seismic acquisition with larger offset and wider azimuth is necessary for seismic imaging in complex areas. However, the scale anisotropy in this case must be taken into account. To generalize the pre-stack depth migration (PSDM) to 3D transversely isotropic media with vertical symmetry axes (VTI) and tilted symmetry axes (TTI) from rugged topography, a new dynamic programming approach for the first-arrival traveltime computation method is proposed. The first-arrival time on every uniform mesh point is calculated based on Fermat's principle with simple calculus techniques and a systematic mapping scheme. In order to calculate the minimum traveltime, a set of nonlinear equations is solved on each mesh point, where the group velocity is determined by the group angle. Based on the new first-arrival time calculation method, the corresponding PSDM and migration velocity analysis workflow for 3D anisotropic media from rugged surface is developed. Numerical tests demonstrate that the proposed traveltime calculation method is effective in both VTI and TTI media. The migration results for 3D field data show that it is necessary to choose a smooth datum to remove the high wavenumber move-out components for PSDM with rugged topography and take anisotropy into account to achieve better images.

  3. Characterization of gas hydrate distribution using conventional 3D seismic data in the Pearl River Mouth Basin, South China Sea

    USGS Publications Warehouse

    Wang, Xiujuan; Qiang, Jin; Collett, Timothy S.; Shi, Hesheng; Yang, Shengxiong; Yan, Chengzhi; Li, Yuanping; Wang, Zhenzhen; Chen, Duanxin

    2016-01-01

    A new 3D seismic reflection data volume acquired in 2012 has allowed for the detailed mapping and characterization of gas hydrate distribution in the Pearl River Mouth Basin in the South China Sea. Previous studies of core and logging data showed that gas hydrate occurrence at high concentrations is controlled by the presence of relatively coarse-grained sediment and the upward migration of thermogenic gas from the deeper sediment section into the overlying gas hydrate stability zone (BGHSZ); however, the spatial distribution of the gas hydrate remains poorly defined. We used a constrained sparse spike inversion technique to generate acoustic-impedance images of the hydrate-bearing sedimentary section from the newly acquired 3D seismic data volume. High-amplitude reflections just above the bottom-simulating reflectors (BSRs) were interpreted to be associated with the accumulation of gas hydrate with elevated saturations. Enhanced seismic reflections below the BSRs were interpreted to indicate the presence of free gas. The base of the BGHSZ was established using the occurrence of BSRs. In areas absent of well-developed BSRs, the BGHSZ was calculated from a model using the inverted P-wave velocity and subsurface temperature data. Seismic attributes were also extracted along the BGHSZ that indicate variations reservoir properties and inferred hydrocarbon accumulations at each site. Gas hydrate saturations estimated from the inversion of acoustic impedance of conventional 3D seismic data, along with well-log-derived rock-physics models were also used to estimate gas hydrate saturations. Our analysis determined that the gas hydrate petroleum system varies significantly across the Pearl River Mouth Basin and that variability in sedimentary properties as a product of depositional processes and the upward migration of gas from deeper thermogenic sources control the distribution of gas hydrates in this basin.

  4. Hands-on guide for 3D image creation for geological purposes

    NASA Astrophysics Data System (ADS)

    Frehner, Marcel; Tisato, Nicola

    2013-04-01

    Geological structures in outcrops or hand specimens are inherently three dimensional (3D), and therefore better understandable if viewed in 3D. While 3D models can easily be created, manipulated, and looked at from all sides on the computer screen (e.g., using photogrammetry or laser scanning data), 3D visualizations for publications or conference posters are much more challenging as they have to live in a 2D-world (i.e., on a sheet of paper). Perspective 2D visualizations of 3D models do not fully transmit the "feeling and depth of the third dimension" to the audience; but this feeling is desirable for a better examination and understanding in 3D of the structure under consideration. One of the very few possibilities to generate real 3D images, which work on a 2D display, is by using so-called stereoscopic images. Stereoscopic images are two images of the same object recorded from two slightly offset viewpoints. Special glasses and techniques have to be used to make sure that one image is seen only by one eye, and the other image is seen by the other eye, which together lead to the "3D effect". Geoscientists are often familiar with such 3D images. For example, geomorphologists traditionally view stereographic orthophotos by employing a mirror-steroscope. Nowadays, petroleum-geoscientists examine high-resolution 3D seismic data sets in special 3D visualization rooms. One of the methods for generating and viewing a stereoscopic image, which does not require a high-tech viewing device, is to create a so-called anaglyph. The principle is to overlay two images saturated in red and cyan, respectively. The two images are then viewed through red-cyan-stereoscopic glasses. This method is simple and cost-effective, but has some drawbacks in preserving colors accurately. A similar method is used in 3D movies, where polarized light or shuttering techniques are used to separate the left from the right image, which allows preserving the original colors. The advantage of red

  5. Using 3D Simulation of Elastic Wave Propagation in Laplace Domain for Electromagnetic-Seismic Inverse Modeling

    NASA Astrophysics Data System (ADS)

    Petrov, P.; Newman, G. A.

    2010-12-01

    -Fourier domain we had developed 3D code for full-wave field simulation in the elastic media which take into account nonlinearity introduced by free-surface effects. Our approach is based on the velocity-stress formulation. In the contrast to conventional formulation we defined the material properties such as density and Lame constants not at nodal points but within cells. This second order finite differences method formulated in the cell-based grid, generate numerical solutions compatible with analytical ones within the range errors determinate by dispersion analysis. Our simulator will be embedded in an inversion scheme for joint seismic- electromagnetic imaging. It also offers possibilities for preconditioning the seismic wave propagation problems in the frequency domain. References. Shin, C. & Cha, Y. (2009), Waveform inversion in the Laplace-Fourier domain, Geophys. J. Int. 177(3), 1067- 1079. Shin, C. & Cha, Y. H. (2008), Waveform inversion in the Laplace domain, Geophys. J. Int. 173(3), 922-931. Commer, M. & Newman, G. (2008), New advances in three-dimensional controlled-source electromagnetic inversion, Geophys. J. Int. 172(2), 513-535. Newman, G. A., Commer, M. & Carazzone, J. J. (2010), Imaging CSEM data in the presence of electrical anisotropy, Geophysics, in press.

  6. A miniature high resolution 3-D imaging sonar.

    PubMed

    Josserand, Tim; Wolley, Jason

    2011-04-01

    This paper discusses the design and development of a miniature, high resolution 3-D imaging sonar. The design utilizes frequency steered phased arrays (FSPA) technology. FSPAs present a small, low-power solution to the problem of underwater imaging sonars. The technology provides a method to build sonars with a large number of beams without the proportional power, circuitry and processing complexity. The design differs from previous methods in that the array elements are manufactured from a monolithic material. With this technique the arrays are flat and considerably smaller element dimensions are achievable which allows for higher frequency ranges and smaller array sizes. In the current frequency range, the demonstrated array has ultra high image resolution (1″ range×1° azimuth×1° elevation) and small size (<3″×3″). The design of the FSPA utilizes the phasing-induced frequency-dependent directionality of a linear phased array to produce multiple beams in a forward sector. The FSPA requires only two hardware channels per array and can be arranged in single and multiple array configurations that deliver wide sector 2-D images. 3-D images can be obtained by scanning the array in a direction perpendicular to the 2-D image field and applying suitable image processing to the multiple scanned 2-D images. This paper introduces the 3-D FSPA concept, theory and design methodology. Finally, results from a prototype array are presented and discussed. PMID:21112066

  7. 3D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

    SciTech Connect

    Levander, Alan Richard; Zelt, Colin A.

    2015-03-17

    The work plan for this project was to develop and apply advanced seismic reflection and wide-angle processing and inversion techniques to high resolution seismic data for the shallow subsurface to seismically characterize the shallow subsurface at hazardous waste sites as an aid to containment and cleanup activities. We proposed to continue work on seismic data that we had already acquired under a previous DoE grant, as well as to acquire additional new datasets for analysis. The project successfully developed and/or implemented the use of 3D reflection seismology algorithms, waveform tomography and finite-frequency tomography using compressional and shear waves for high resolution characterization of the shallow subsurface at two waste sites. These two sites have markedly different near-surface structures, groundwater flow patterns, and hazardous waste problems. This is documented in the list of refereed documents, conference proceedings, and Rice graduate theses, listed below.

  8. 3D reconstruction based on CT image and its application

    NASA Astrophysics Data System (ADS)

    Zhang, Jianxun; Zhang, Mingmin

    2004-03-01

    Reconstitute the 3-D model of the liver and its internal piping system and simulation of the liver surgical operation can increase the accurate and security of the liver surgical operation, attain a purpose for the biggest limit decrease surgical operation wound, shortening surgical operation time, increasing surgical operation succeeding rate, reducing medical treatment expenses and promoting patient recovering from illness. This text expatiated technology and method that the author constitutes 3-D the model of the liver and its internal piping system and simulation of the liver surgical operation according to the images of CT. The direct volume rendering method establishes 3D the model of the liver. Under the environment of OPENGL adopt method of space point rendering to display liver's internal piping system and simulation of the liver surgical operation. Finally, we adopt the wavelet transform method compressed the medical image data.

  9. 3-D Display Of Magnetic Resonance Imaging Of The Spine

    NASA Astrophysics Data System (ADS)

    Nelson, Alan C.; Kim, Yongmin; Haralick, Robert M.; Anderson, Paul A.; Johnson, Roger H.; DeSoto, Larry A.

    1988-06-01

    The original data is produced through standard magnetic resonance imaging (MRI) procedures with a surface coil applied to the lower back of a normal human subject. The 3-D spine image data consists of twenty-six contiguous slices with 256 x 256 pixels per slice. Two methods for visualization of the 3-D spine are explored. One method utilizes a verifocal mirror system which creates a true 3-D virtual picture of the object. Another method uses a standard high resolution monitor to simultaneously show the three orthogonal sections which intersect at any user-selected point within the object volume. We discuss the application of these systems in assessment of low back pain.

  10. Evolution of Submarine Gullies on a Prograding Slope: Insights from 3D Seismic Reflection Data

    NASA Astrophysics Data System (ADS)

    Shumaker, L.; Jobe, Z. R.

    2014-12-01

    Submarine gullies are common features on continental slopes on both passive and active margins, but the processes dictating gully formation and the role of gullies in deep-water sediment transport are topics of debate. The geometries of gullies can provide clues to understanding the processes by which they initiate and grow, particularly when considered in the context of surrounding submarine geomorphology. Further confidence in these interpretations can be gained by tracking the temporal history of gullies with evolution of the continental margin. The 500 km2 Tui 3D seismic survey from the Taranaki Basin, New Zealand, shows continental slope gullies and other channel features in a ~1 km-thick package of prograding shelf-slope clinoforms that developed over Pliocene-Pleistocene time. This dataset allows for documentation of gullies over ~3 Ma, through numerous cycles of initiation and burial. For this study, we manually interpreted clinoform packages to generate 'paleo-seafloor' surfaces that provide context such as position of the shelf edge, slope gradient and azimuth, and relative progradation and aggradation magnitudes. Gully geometries were obtained from detailed seismic interpretation guided by semblance and RMS amplitude imaging on these surfaces. Gullies are low sinuosity, with widths ranging from ~50-150 m and depths from a few tens to <100 m. Gullies are observed to grow in width and relief downslope without evidence for aggradational confinement (levees), and in some cases form gully 'complexes' hundreds of m wide in the lower slope region. These complexes are present through >150 m of stratigraphy, indicating that they are long-lived features on the slope. This further indicates that the frequency of flows along the gullies was enough to maintain their topographic expression during slope progradation and aggradation, and suggests that gullies play an integral role in transport processes on the slope.

  11. Reconstruction of 3D scenes from sequences of images

    NASA Astrophysics Data System (ADS)

    Niu, Bei; Sang, Xinzhu; Chen, Duo; Cai, Yuanfa

    2013-08-01

    Reconstruction of three-dimensional (3D) scenes is an active research topic in the field of computer vision and 3D display. It's a challenge to model 3D objects rapidly and effectively. A 3D model can be extracted from multiple images. The system only requires a sequence of images taken with cameras without knowing the parameters of camera, which provide flexibility to a high degree. We focus on quickly merging point cloud of the object from depth map sequences. The whole system combines algorithms of different areas in computer vision, such as camera calibration, stereo correspondence, point cloud splicing and surface reconstruction. The procedure of 3D reconstruction is decomposed into a number of successive steps. Firstly, image sequences are received by the camera freely moving around the object. Secondly, the scene depth is obtained by a non-local stereo matching algorithm. The pairwise is realized with the Scale Invariant Feature Transform (SIFT) algorithm. An initial matching is then made for the first two images of the sequence. For the subsequent image that is processed with previous image, the point of interest corresponding to ones in previous images are refined or corrected. The vertical parallax between the images is eliminated. The next step is to calibrate camera, and intrinsic parameters and external parameters of the camera are calculated. Therefore, The relative position and orientation of camera are gotten. A sequence of depth maps are acquired by using a non-local cost aggregation method for stereo matching. Then point cloud sequence is achieved by the scene depths, which consists of point cloud model using the external parameters of camera and the point cloud sequence. The point cloud model is then approximated by a triangular wire-frame mesh to reduce geometric complexity and to tailor the model to the requirements of computer graphics visualization systems. Finally, the texture is mapped onto the wire-frame model, which can also be used for 3

  12. ActiveSeismoPick3D - automatic first arrival determination for large active seismic arrays

    NASA Astrophysics Data System (ADS)

    Paffrath, Marcel; Küperkoch, Ludger; Wehling-Benatelli, Sebastian; Friederich, Wolfgang

    2016-04-01

    We developed a tool for automatic determination of first arrivals in active seismic data based on an approach, that utilises higher order statistics (HOS) and the Akaike information criterion (AIC), commonly used in seismology, but not in active seismics. Automatic picking is highly desirable in active seismics as the number of data provided by large seismic arrays rapidly exceeds of what an analyst can evaluate in a reasonable amount of time. To bring the functionality of automatic phase picking into the context of active data, the software package ActiveSeismoPick3D was developed in Python. It uses a modified algorithm for the determination of first arrivals which searches for the HOS maximum in unfiltered data. Additionally, it offers tools for manual quality control and postprocessing, e.g. various visualisation and repicking functionalities. For flexibility, the tool also includes methods for the preparation of geometry information of large seismic arrays and improved interfaces to the Fast Marching Tomography Package (FMTOMO), which can be used for the prediction of travel times and inversion for subsurface properties. Output files are generated in the VTK format, allowing the 3D visualization of e.g. the inversion results. As a test case, a data set consisting of 9216 traces from 64 shots was gathered, recorded at 144 receivers deployed in a regular 2D array of a size of 100 x 100 m. ActiveSeismoPick3D automatically checks the determined first arrivals by a dynamic signal to noise ratio threshold. From the data a 3D model of the subsurface was generated using the export functionality of the package and FMTOMO.

  13. Wave-CAIPI for Highly Accelerated 3D Imaging

    PubMed Central

    Bilgic, Berkin; Gagoski, Borjan A.; Cauley, Stephen F.; Fan, Audrey P.; Polimeni, Jonathan R.; Grant, P. Ellen; Wald, Lawrence L.; Setsompop, Kawin

    2014-01-01

    Purpose To introduce the Wave-CAIPI (Controlled Aliasing in Parallel Imaging) acquisition and reconstruction technique for highly accelerated 3D imaging with negligible g-factor and artifact penalties. Methods The Wave-CAIPI 3D acquisition involves playing sinusoidal gy and gz gradients during the readout of each kx encoding line, while modifying the 3D phase encoding strategy to incur inter-slice shifts as in 2D-CAIPI acquisitions. The resulting acquisition spreads the aliasing evenly in all spatial directions, thereby taking full advantage of 3D coil sensitivity distribution. By expressing the voxel spreading effect as a convolution in image space, an efficient reconstruction scheme that does not require data gridding is proposed. Rapid acquisition and high quality image reconstruction with Wave-CAIPI is demonstrated for high-resolution magnitude and phase imaging and Quantitative Susceptibility Mapping (QSM). Results Wave-CAIPI enables full-brain gradient echo (GRE) acquisition at 1 mm isotropic voxel size and R=3×3 acceleration with maximum g-factors of 1.08 at 3T, and 1.05 at 7T. Relative to the other advanced Cartesian encoding strategies 2D-CAIPI and Bunched Phase Encoding, Wave-CAIPI yields up to 2-fold reduction in maximum g-factor for 9-fold acceleration at both field strengths. Conclusion Wave-CAIPI allows highly accelerated 3D acquisitions with low artifact and negligible g-factor penalties, and may facilitate clinical application of high-resolution volumetric imaging. PMID:24986223

  14. Automated curved planar reformation of 3D spine images

    NASA Astrophysics Data System (ADS)

    Vrtovec, Tomaz; Likar, Bostjan; Pernus, Franjo

    2005-10-01

    Traditional techniques for visualizing anatomical structures are based on planar cross-sections from volume images, such as images obtained by computed tomography (CT) or magnetic resonance imaging (MRI). However, planar cross-sections taken in the coordinate system of the 3D image often do not provide sufficient or qualitative enough diagnostic information, because planar cross-sections cannot follow curved anatomical structures (e.g. arteries, colon, spine, etc). Therefore, not all of the important details can be shown simultaneously in any planar cross-section. To overcome this problem, reformatted images in the coordinate system of the inspected structure must be created. This operation is usually referred to as curved planar reformation (CPR). In this paper we propose an automated method for CPR of 3D spine images, which is based on the image transformation from the standard image-based to a novel spine-based coordinate system. The axes of the proposed spine-based coordinate system are determined on the curve that represents the vertebral column, and the rotation of the vertebrae around the spine curve, both of which are described by polynomial models. The optimal polynomial parameters are obtained in an image analysis based optimization framework. The proposed method was qualitatively and quantitatively evaluated on five CT spine images. The method performed well on both normal and pathological cases and was consistent with manually obtained ground truth data. The proposed spine-based CPR benefits from reduced structural complexity in favour of improved feature perception of the spine. The reformatted images are diagnostically valuable and enable easier navigation, manipulation and orientation in 3D space. Moreover, reformatted images may prove useful for segmentation and other image analysis tasks.

  15. Practical pseudo-3D registration for large tomographic images

    NASA Astrophysics Data System (ADS)

    Liu, Xuan; Laperre, Kjell; Sasov, Alexander

    2014-09-01

    Image registration is a powerful tool in various tomographic applications. Our main focus is on microCT applications in which samples/animals can be scanned multiple times under different conditions or at different time points. For this purpose, a registration tool capable of handling fairly large volumes has been developed, using a novel pseudo-3D method to achieve fast and interactive registration with simultaneous 3D visualization. To reduce computation complexity in 3D registration, we decompose it into several 2D registrations, which are applied to the orthogonal views (transaxial, sagittal and coronal) sequentially and iteratively. After registration in each view, the next view is retrieved with the new transformation matrix for registration. This reduces the computation complexity significantly. For rigid transform, we only need to search for 3 parameters (2 shifts, 1 rotation) in each of the 3 orthogonal views instead of 6 (3 shifts, 3 rotations) for full 3D volume. In addition, the amount of voxels involved is also significantly reduced. For the proposed pseudo-3D method, image-based registration is employed, with Sum of Square Difference (SSD) as the similarity measure. The searching engine is Powell's conjugate direction method. In this paper, only rigid transform is used. However, it can be extended to affine transform by adding scaling and possibly shearing to the transform model. We have noticed that more information can be used in the 2D registration if Maximum Intensity Projections (MIP) or Parallel Projections (PP) is used instead of the orthogonal views. Also, other similarity measures, such as covariance or mutual information, can be easily incorporated. The initial evaluation on microCT data shows very promising results. Two application examples are shown: dental samples before and after treatment and structural changes in materials before and after compression. Evaluation on registration accuracy between pseudo-3D method and true 3D method has

  16. 3D Porosity Estimation of the Nankai Trough Sediments from Core-log-seismic Integration

    NASA Astrophysics Data System (ADS)

    Park, J. O.

    2015-12-01

    The Nankai Trough off southwest Japan is one of the best subduction-zone to study megathrust earthquake fault. Historic, great megathrust earthquakes with a recurrence interval of 100-200 yr have generated strong motion and large tsunamis along the Nankai Trough subduction zone. At the Nankai Trough margin, the Philippine Sea Plate (PSP) is being subducted beneath the Eurasian Plate to the northwest at a convergence rate ~4 cm/yr. The Shikoku Basin, the northern part of the PSP, is estimated to have opened between 25 and 15 Ma by backarc spreading of the Izu-Bonin arc. The >100-km-wide Nankai accretionary wedge, which has developed landward of the trench since the Miocene, mainly consists of offscraped and underplated materials from the trough-fill turbidites and the Shikoku Basin hemipelagic sediments. Particularly, physical properties of the incoming hemipelagic sediments may be critical for seismogenic behavior of the megathrust fault. We have carried out core-log-seismic integration (CLSI) to estimate 3D acoustic impedance and porosity for the incoming sediments in the Nankai Trough. For the CLSI, we used 3D seismic reflection data, P-wave velocity and density data obtained during IODP (Integrated Ocean Drilling Program) Expeditions 322 and 333. We computed acoustic impedance depth profiles for the IODP drilling sites from P-wave velocity and density data. We constructed seismic convolution models with the acoustic impedance profiles and a source wavelet which is extracted from the seismic data, adjusting the seismic models to observed seismic traces with inversion method. As a result, we obtained 3D acoustic impedance volume and then converted it to 3D porosity volume. In general, the 3D porosities show decrease with depth. We found a porosity anomaly zone with alteration of high and low porosities seaward of the trough axis. In this talk, we will show detailed 3D porosity of the incoming sediments, and present implications of the porosity anomaly zone for the

  17. 3D wavefront image formation for NIITEK GPR

    NASA Astrophysics Data System (ADS)

    Soumekh, Mehrdad; Ton, Tuan; Howard, Pete

    2009-05-01

    The U.S. Department of Defense Humanitarian Demining (HD) Research and Development Program focuses on developing, testing, demonstrating, and validating new technology for immediate use in humanitarian demining operations around the globe. Beginning in the late 1990's, the U.S. Army Countermine Division funded the development of the NIITEK ground penetrating radar (GPR) for detection of anti-tank (AT) landmines. This work is concerned with signal processing algorithms to suppress sources of artifacts in the NIITEK GPR, and formation of three-dimensional (3D) imagery from the resultant data. We first show that the NIITEK GPR data correspond to a 3D Synthetic Aperture Radar (SAR) database. An adaptive filtering method is utilized to suppress ground return and self-induced resonance (SIR) signals that are generated by the interaction of the radar-carrying platform and the transmitted radar signal. We examine signal processing methods to improve the fidelity of imagery for this 3D SAR system using pre-processing methods that suppress Doppler aliasing as well as other side lobe leakage artifacts that are introduced by the radar radiation pattern. The algorithm, known as digital spotlighting, imposes a filtering scheme on the azimuth-compressed SAR data, and manipulates the resultant spectral data to achieve a higher PRF to suppress the Doppler aliasing. We also present the 3D version of the Fourier-based wavefront reconstruction, a computationally-efficient and approximation-free SAR imaging method, for image formation with the NIITEK 3D SAR database.

  18. Optimizing 3D image quality and performance for stereoscopic gaming

    NASA Astrophysics Data System (ADS)

    Flack, Julien; Sanderson, Hugh; Pegg, Steven; Kwok, Simon; Paterson, Daniel

    2009-02-01

    The successful introduction of stereoscopic TV systems, such as Samsung's 3D Ready Plasma, requires high quality 3D content to be commercially available to the consumer. Console and PC games provide the most readily accessible source of high quality 3D content. This paper describes innovative developments in a generic, PC-based game driver architecture that addresses the two key issues affecting 3D gaming: quality and speed. At the heart of the quality issue are the same considerations that studios face producing stereoscopic renders from CG movies: how best to perform the mapping from a geometric CG environment into the stereoscopic display volume. The major difference being that for game drivers this mapping cannot be choreographed by hand but must be automatically calculated in real-time without significant impact on performance. Performance is a critical issue when dealing with gaming. Stereoscopic gaming has traditionally meant rendering the scene twice with the associated performance overhead. An alternative approach is to render the scene from one virtual camera position and use information from the z-buffer to generate a stereo pair using Depth-Image-Based Rendering (DIBR). We analyze this trade-off in more detail and provide some results relating to both 3D image quality and render performance.

  19. Complex Crustal Structure Beneath Western Turkey Revealed by 3D Seismic Full Waveform Inversion (FWI)

    NASA Astrophysics Data System (ADS)

    Cubuk-Sabuncu, Yesim; Taymaz, Tuncay; Fichtner, Andreas

    2016-04-01

    We present a 3D radially anisotropic velocity model of the crust and uppermost mantle structure beneath the Sea of Marmara and surroundings based on the full waveform inversion method. The intense seismic activity and crustal deformation are observed in the Northwest Turkey due to transition tectonics between the strike-slip North Anatolian Fault (NAF) and the extensional Aegean region. We have selected and simulated complete waveforms of 62 earthquakes (Mw > 4.0) occurred during 2007-2015, and recorded at (Δ < 10°) distances. Three component earthquake data is obtained from broadband seismic stations of Kandilli Observatory and Earthquake Research Center (KOERI, Turkey), Hellenic Unified Seismic Network (HUSN, Greece) and Earthquake Research Center of Turkey (AFAD-DAD). The spectral-element solver of the wave equation, SES3D algorithm, is used to simulate seismic wave propagation in 3D spherical coordinates (Fichtner, 2009). The Large Scale Seismic Inversion Framework (LASIF) workflow tool is also used to perform full seismic waveform inversion (Krischer et al., 2015). The initial 3D Earth model is implemented from the multi-scale seismic tomography study of Fichtner et al. (2013). Discrepancies between the observed and simulated synthetic waveforms are determined using the time-frequency misfits which allows a separation between phase and amplitude information (Fichtner et al., 2008). The conjugate gradient optimization method is used to iteratively update the initial Earth model when minimizing the misfit. The inversion is terminated after 19 iterations since no further advances are observed in updated models. Our analysis revealed shear wave velocity variations of the shallow and deeper crustal structure beneath western Turkey down to depths of ~35-40 km. Low shear wave velocity anomalies are observed in the upper and mid crustal depths beneath major fault zones located in the study region. Low velocity zones also tend to mark the outline of young volcanic

  20. 3-D object-oriented image analysis of geophysical data

    NASA Astrophysics Data System (ADS)

    Fadel, I.; Kerle, N.; van der Meijde, M.

    2014-07-01

    Geophysical data are the main source of information about the subsurface. Geophysical techniques are, however, highly non-unique in determining specific physical parameters and boundaries of subsurface objects. To obtain actual physical information, an inversion process is often applied, in which measurements at or above the Earth surface are inverted into a 2- or 3-D subsurface spatial distribution of the physical property. Interpreting these models into structural objects, related to physical processes, requires a priori knowledge and expert analysis which is susceptible to subjective choices and is therefore often non-repeatable. In this research, we implemented a recently introduced object-based approach to interpret the 3-D inversion results of a single geophysical technique using the available a priori information and the physical and geometrical characteristics of the interpreted objects. The introduced methodology is semi-automatic and repeatable, and allows the extraction of subsurface structures using 3-D object-oriented image analysis (3-D OOA) in an objective knowledge-based classification scheme. The approach allows for a semi-objective setting of thresholds that can be tested and, if necessary, changed in a very fast and efficient way. These changes require only changing the thresholds used in a so-called ruleset, which is composed of algorithms that extract objects from a 3-D data cube. The approach is tested on a synthetic model, which is based on a priori knowledge on objects present in the study area (Tanzania). Object characteristics and thresholds were well defined in a 3-D histogram of velocity versus depth, and objects were fully retrieved. The real model results showed how 3-D OOA can deal with realistic 3-D subsurface conditions in which the boundaries become fuzzy, the object extensions become unclear and the model characteristics vary with depth due to the different physical conditions. As expected, the 3-D histogram of the real data was

  1. Practical applications of 3D sonography in gynecologic imaging.

    PubMed

    Andreotti, Rochelle F; Fleischer, Arthur C

    2014-11-01

    Volume imaging in the pelvis has been well demonstrated to be an extremely useful technique, largely based on its ability to reconstruct the coronal plane of the uterus that usually cannot be visualized using traditional 2-dimensional (2D) imaging. As a result, this technique is now a part of the standard pelvic ultrasound protocol in many institutions. A variety of valuable applications of 3D sonography in the pelvis are discussed in this article. PMID:25444101

  2. 3D Winding Number: Theory and Application to Medical Imaging

    PubMed Central

    Becciu, Alessandro; Fuster, Andrea; Pottek, Mark; van den Heuvel, Bart; ter Haar Romeny, Bart; van Assen, Hans

    2011-01-01

    We develop a new formulation, mathematically elegant, to detect critical points of 3D scalar images. It is based on a topological number, which is the generalization to three dimensions of the 2D winding number. We illustrate our method by considering three different biomedical applications, namely, detection and counting of ovarian follicles and neuronal cells and estimation of cardiac motion from tagged MR images. Qualitative and quantitative evaluation emphasizes the reliability of the results. PMID:21317978

  3. An automated 3D reconstruction method of UAV images

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Wang, He; Liu, Xiaoyang; Li, Feng; Sun, Guangtong; Song, Ping

    2015-10-01

    In this paper a novel fully automated 3D reconstruction approach based on low-altitude unmanned aerial vehicle system (UAVs) images will be presented, which does not require previous camera calibration or any other external prior knowledge. Dense 3D point clouds are generated by integrating orderly feature extraction, image matching, structure from motion (SfM) and multi-view stereo (MVS) algorithms, overcoming many of the cost, time limitations of rigorous photogrammetry techniques. An image topology analysis strategy is introduced to speed up large scene reconstruction by taking advantage of the flight-control data acquired by UAV. Image topology map can significantly reduce the running time of feature matching by limiting the combination of images. A high-resolution digital surface model of the study area is produced base on UAV point clouds by constructing the triangular irregular network. Experimental results show that the proposed approach is robust and feasible for automatic 3D reconstruction of low-altitude UAV images, and has great potential for the acquisition of spatial information at large scales mapping, especially suitable for rapid response and precise modelling in disaster emergency.

  4. 3D ultrasound image segmentation using wavelet support vector machines

    PubMed Central

    Akbari, Hamed; Fei, Baowei

    2012-01-01

    Purpose: Transrectal ultrasound (TRUS) imaging is clinically used in prostate biopsy and therapy. Segmentation of the prostate on TRUS images has many applications. In this study, a three-dimensional (3D) segmentation method for TRUS images of the prostate is presented for 3D ultrasound-guided biopsy. Methods: This segmentation method utilizes a statistical shape, texture information, and intensity profiles. A set of wavelet support vector machines (W-SVMs) is applied to the images at various subregions of the prostate. The W-SVMs are trained to adaptively capture the features of the ultrasound images in order to differentiate the prostate and nonprostate tissue. This method consists of a set of wavelet transforms for extraction of prostate texture features and a kernel-based support vector machine to classify the textures. The voxels around the surface of the prostate are labeled in sagittal, coronal, and transverse planes. The weight functions are defined for each labeled voxel on each plane and on the model at each region. In the 3D segmentation procedure, the intensity profiles around the boundary between the tentatively labeled prostate and nonprostate tissue are compared to the prostate model. Consequently, the surfaces are modified based on the model intensity profiles. The segmented prostate is updated and compared to the shape model. These two steps are repeated until they converge. Manual segmentation of the prostate serves as the gold standard and a variety of methods are used to evaluate the performance of the segmentation method. Results: The results from 40 TRUS image volumes of 20 patients show that the Dice overlap ratio is 90.3% ± 2.3% and that the sensitivity is 87.7% ± 4.9%. Conclusions: The proposed method provides a useful tool in our 3D ultrasound image-guided prostate biopsy and can also be applied to other applications in the prostate. PMID:22755682

  5. 3-D seismic case history of the dawn 156 pinnacle reef

    SciTech Connect

    Egden, J.G.; Horan, M.T. ); Nader, S.M. )

    1994-08-01

    Silurian pinnacle reefs are used for gas storage in southern Ontario and southeast Michigan. These reefs underlie surface culture that is frequently incompatible with enhanced reservoir exploitation techniques such as 3-D seismic. Further complications are encountered due to an increased awareness of environmental concerns and past exploration or local production practices. Employing proactive project management in a team-oriented environment, Union Gas Ltd., successfully conducted a 2732 ac 3-D seismic survey in 1993-1994. The project brought together a multidisciplinary team that included company employees, consultants, service companies, and surface landowners. This case history covers the project from conceptualization through the team-building processes and final selection of additional drilling locations. The project management philosophy employed has potential application in the upstream sector.

  6. 1024 pixels single photon imaging array for 3D ranging

    NASA Astrophysics Data System (ADS)

    Bellisai, S.; Guerrieri, F.; Tisa, S.; Zappa, F.; Tosi, A.; Giudice, A.

    2011-01-01

    Three dimensions (3D) acquisition systems are driving applications in many research field. Nowadays 3D acquiring systems are used in a lot of applications, such as cinema industry or in automotive (for active security systems). Depending on the application, systems present different features, for example color sensitivity, bi-dimensional image resolution, distance measurement accuracy and acquisition frame rate. The system we developed acquires 3D movie using indirect Time of Flight (iTOF), starting from phase delay measurement of a sinusoidally modulated light. The system acquires live movie with a frame rate up to 50frame/s in a range distance between 10 cm up to 7.5 m.

  7. 3-D segmentation of human sternum in lung MDCT images.

    PubMed

    Pazokifard, Banafsheh; Sowmya, Arcot

    2013-01-01

    A fully automatic novel algorithm is presented for accurate 3-D segmentation of the human sternum in lung multi detector computed tomography (MDCT) images. The segmentation result is refined by employing active contours to remove calcified costal cartilage that is attached to the sternum. For each dataset, costal notches (sternocostal joints) are localized in 3-D by using a sternum mask and positions of the costal notches on it as reference. The proposed algorithm for sternum segmentation was tested on 16 complete lung MDCT datasets and comparison of the segmentation results to the reference delineation provided by a radiologist, shows high sensitivity (92.49%) and specificity (99.51%) and small mean distance (dmean=1.07 mm). Total average of the Euclidean distance error for costal notches positioning in 3-D is 4.2 mm. PMID:24110446

  8. Incremental volume reconstruction and rendering for 3-D ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Ohbuchi, Ryutarou; Chen, David; Fuchs, Henry

    1992-09-01

    In this paper, we present approaches toward an interactive visualization of a real time input, applied to 3-D visualizations of 2-D ultrasound echography data. The first, 3 degrees-of- freedom (DOF) incremental system visualizes a 3-D volume acquired as a stream of 2-D slices with location and orientation with 3 DOF. As each slice arrives, the system reconstructs a regular 3-D volume and renders it. Rendering is done by an incremental image-order ray- casting algorithm which stores and reuses the results of expensive resampling along the rays for speed. The second is our first experiment toward real-time 6 DOF acquisition and visualization. Two-dimensional slices with 6 DOF are reconstructed off-line, and visualized at an interactive rate using a parallel volume rendering code running on the graphics multicomputer Pixel-Planes 5.

  9. Automatic needle segmentation in 3D ultrasound images

    NASA Astrophysics Data System (ADS)

    Ding, Mingyue; Cardinal, H. Neale; Guan, Weiguang; Fenster, Aaron

    2002-05-01

    In this paper, we propose to use 2D image projections to automatically segment a needle in a 3D ultrasound image. This approach is motivated by the twin observations that the needle is more conspicuous in a projected image, and its projected area is a minimum when the rays are cast parallel to the needle direction. To avoid the computational burden of an exhaustive 2D search for the needle direction, a faster 1D search procedure is proposed. First, a plane which contains the needle direction is determined by the initial projection direction and the (estimated) direction of the needle in the corresponding projection image. Subsequently, an adaptive 1D search technique is used to adjust the projection direction iteratively until the projected needle area is minimized. In order to remove noise and complex background structure from the projection images, a priori information about the needle position and orientation is used to crop the 3D volume, and the cropped volume is rendered with Gaussian transfer functions. We have evaluated this approach experimentally using agar and turkey breast phantoms. The results show that it can find the 3D needle orientation within 1 degree, in about 1 to 3 seconds on a 500 MHz computer.

  10. Vhrs Stereo Images for 3d Modelling of Buildings

    NASA Astrophysics Data System (ADS)

    Bujakiewicz, A.; Holc, M.

    2012-07-01

    The paper presents the project which was carried out in the Photogrammetric Laboratory of Warsaw University of Technology. The experiment is concerned with the extraction of 3D vector data for buildings creation from 3D photogrammetric model based on the Ikonos stereo images. The model was reconstructed with photogrammetric workstation - Summit Evolution combined with ArcGIS 3D platform. Accuracy of 3D model was significantly improved by use for orientation of pair of satellite images the stereo measured tie points distributed uniformly around the model area in addition to 5 control points. The RMS for model reconstructed on base of the RPC coefficients only were 16,6 m, 2,7 m and 47,4 m, for X, Y and Z coordinates, respectively. By addition of 5 control points the RMS were improved to 0,7 m, 0,7 m 1,0 m, where the best results were achieved when RMS were estimated from deviations in 17 check points (with 5 control points)and amounted to 0,4 m, 0,5 m and 0,6 m, for X, Y, and Z respectively. The extracted 3D vector data for buildings were integrated with 2D data of the ground footprints and afterwards they were used for 3D modelling of buildings in Google SketchUp software. The final results were compared with the reference data obtained from other sources. It was found that the shape of buildings (in concern to the number of details) had been reconstructed on level of LoD1, when the accuracy of these models corresponded to the level of LoD2.

  11. 3D multicomponent seismic characterization of a clastic reservoir in the Middle Magdalena Valley Basin, Colombia

    NASA Astrophysics Data System (ADS)

    Velasquez-Espejo, Antonio Jose

    The main goal of this research is to characterize the combined structural-stratigraphic trap of the Tenerife Field in the Middle Magdalena Valley Basin (MMVB), Colombia. For the first time in Colombia the structural and quantitative interpretation of modern three-dimensional multicomponent (3D-3C) seismic imaging enables a geometric description, a kinematic interpretation of the structural styles, and the facies distribution of the reservoir. A seismic petrophysics work-flow to better achieve the seismic well-tie. Edited and check-shot calibrated P-wave sonic logs were obtained and coefficients of the Gardner and Castagna equations were calibrated to match the density and shear-wave velocity depth trends for the basin. Seismic modeling was performed to evaluate the PP and PS seismic response of the reservoir interval (Mugrosa Formation). The structural interpretation methodology involves a 3D fault-correlation and horizon picking for both PP- and PS-PSTM data volumes. Geometric attributes such as coherence and curvature were used to enhance the structural discontinuities. The main unconformity of the Middle Eocene (MEU) was interpreted, and an attribute-assisted interpretation of the reservoir was conducted in detail. While P-wave data provided most of the structural interpretation, converted-wave data provide a better understanding of the faults. Traditionally, compressive thrust-propagation folds and tectonic inversion have been considered as the main mechanisms controlling the deformation in the MMVB. However, the new interpretation shown in this work provides a different structural concept that involves two major structural styles: 1. Under the MEU the Late Cretaceous and Early Paleocene deformation, dominated by east-verging thrust and partially inverted Mesozoic normal faults, is preserved. Associated folds exhibit a north-south strike, and their structural development is controlled by a long-lived structural element that dominates the area (the Infantas

  12. 3D Reconstruction of Human Motion from Monocular Image Sequences.

    PubMed

    Wandt, Bastian; Ackermann, Hanno; Rosenhahn, Bodo

    2016-08-01

    This article tackles the problem of estimating non-rigid human 3D shape and motion from image sequences taken by uncalibrated cameras. Similar to other state-of-the-art solutions we factorize 2D observations in camera parameters, base poses and mixing coefficients. Existing methods require sufficient camera motion during the sequence to achieve a correct 3D reconstruction. To obtain convincing 3D reconstructions from arbitrary camera motion, our method is based on a-priorly trained base poses. We show that strong periodic assumptions on the coefficients can be used to define an efficient and accurate algorithm for estimating periodic motion such as walking patterns. For the extension to non-periodic motion we propose a novel regularization term based on temporal bone length constancy. In contrast to other works, the proposed method does not use a predefined skeleton or anthropometric constraints and can handle arbitrary camera motion. We achieve convincing 3D reconstructions, even under the influence of noise and occlusions. Multiple experiments based on a 3D error metric demonstrate the stability of the proposed method. Compared to other state-of-the-art methods our algorithm shows a significant improvement. PMID:27093439

  13. Combined interpretation of 3D seismic reflection attributes for geothermal exploration in the Polish Basin using self-organizing maps

    NASA Astrophysics Data System (ADS)

    Bauer, Klaus; Pussak, Marcin; Stiller, Manfred; Bujakowski, Wieslaw

    2014-05-01

    Self-organizing maps (SOM) are neural network techniques which can be used for the joint interpretation of multi-disciplinary data sets. In this investigation we apply SOM within a geothermal exploration project using 3D seismic reflection data. The study area is located in the central part of the Polish basin. Several sedimentary target horizons were identified at this location based on fluid flow rate measurements in the geothermal research well Kompina-2. The general objective is a seismic facies analysis and characterization of the major geothermal target reservoir. A 3D seismic reflection experiment with a sparse acquisition geometry was carried out around well Kompina-2. Conventional signal processing (amplitude corrections, filtering, spectral whitening, deconvolution, static corrections, muting) was followed by normal-moveout (NMO) stacking, and, alternatively, by common-reflection-surface (CRS) stacking. Different signal attributes were then derived from the stacked images including root-mean-square (RMS) amplitude, instantaneous frequency and coherency. Furthermore, spectral decomposition attributes were calculated based on the continuous wavelet transform. The resulting attribute maps along major target horizons appear noisy after the NMO stack and clearly structured after the CRS stack. Consequently, the following SOM-based multi-parameter signal attribute analysis was applied only to the CRS images. We applied our SOM work flow, which includes data preparation, unsupervised learning, segmentation of the trained SOM using image processing techniques, and final application of the learned knowledge. For the Lower Jurassic target horizon Ja1 we derived four different clusters with distinct seismic attribute signatures. As the most striking feature, a corridor parallel to a fault system was identified, which is characterized by decreased RMS amplitudes and low frequencies. In our interpretation we assume that this combination of signal properties can be

  14. Large distance 3D imaging of hidden objects

    NASA Astrophysics Data System (ADS)

    Rozban, Daniel; Aharon Akram, Avihai; Kopeika, N. S.; Abramovich, A.; Levanon, Assaf

    2014-06-01

    Imaging systems in millimeter waves are required for applications in medicine, communications, homeland security, and space technology. This is because there is no known ionization hazard for biological tissue, and atmospheric attenuation in this range of the spectrum is low compared to that of infrared and optical rays. The lack of an inexpensive room temperature detector makes it difficult to give a suitable real time implement for the above applications. A 3D MMW imaging system based on chirp radar was studied previously using a scanning imaging system of a single detector. The system presented here proposes to employ a chirp radar method with Glow Discharge Detector (GDD) Focal Plane Array (FPA of plasma based detectors) using heterodyne detection. The intensity at each pixel in the GDD FPA yields the usual 2D image. The value of the I-F frequency yields the range information at each pixel. This will enable 3D MMW imaging. In this work we experimentally demonstrate the feasibility of implementing an imaging system based on radar principles and FPA of inexpensive detectors. This imaging system is shown to be capable of imaging objects from distances of at least 10 meters.

  15. Automated reconstruction of 3D scenes from sequences of images

    NASA Astrophysics Data System (ADS)

    Pollefeys, M.; Koch, R.; Vergauwen, M.; Van Gool, L.

    Modelling of 3D objects from image sequences is a challenging problem and has been an important research topic in the areas of photogrammetry and computer vision for many years. In this paper, a system is presented which automatically extracts a textured 3D surface model from a sequence of images of a scene. The system can deal with unknown camera settings. In addition, the parameters of this camera are allowed to change during acquisition (e.g., by zooming or focusing). No prior knowledge about the scene is necessary to build the 3D models. Therefore, this system offers a high degree of flexibility. The system is based on state-of-the-art algorithms recently developed in computer vision. The 3D modelling task is decomposed into a number of successive steps. Gradually, more knowledge of the scene and the camera setup is retrieved. At this point, the obtained accuracy is not yet at the level required for most metrology applications, but the visual quality is very convincing. This system has been applied to a number of applications in archaeology. The Roman site of Sagalassos (southwest Turkey) was used as a test case to illustrate the potential of this new approach.

  16. 3D imaging of fetus vertebra by synchrotron radiation microtomography

    NASA Astrophysics Data System (ADS)

    Peyrin, Francoise; Pateyron-Salome, Murielle; Denis, Frederic; Braillon, Pierre; Laval-Jeantet, Anne-Marie; Cloetens, Peter

    1997-10-01

    A synchrotron radiation computed microtomography system allowing high resolution 3D imaging of bone samples has been developed at ESRF. The system uses a high resolution 2D detector based on a CCd camera coupled to a fluorescent screen through light optics. The spatial resolution of the device is particularly well adapted to the imaging of bone structure. In view of studying growth, vertebra samples of fetus with differential gestational ages were imaged. The first results show that fetus vertebra is quite different from adult bone both in terms of density and organization.

  17. Texture blending on 3D models using casual images

    NASA Astrophysics Data System (ADS)

    Liu, Xingming; Liu, Xiaoli; Li, Ameng; Liu, Junyao; Wang, Huijing

    2013-12-01

    In this paper, a method for constructing photorealistic textured model using 3D structured light digitizer is presented. Our method acquisition of range images and texture images around object, and range images are registered and integrated to construct geometric model of object. System is calibrated and poses of texture-camera are determined so that the relationship between texture and geometric model is established. After that, a global optimization is applied to assign compatible texture to adjacent surface and followed with a level procedure to remove artifacts due to vary lighting, approximate geometric model and so on. Lastly, we demonstrate the effect of our method on constructing a real model of world.

  18. Combined registration of 3D tibia and femur implant models in 3D magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Englmeier, Karl-Hans; Siebert, Markus; von Eisenhart-Rothe, Ruediger; Graichen, Heiko

    2008-03-01

    The most frequent reasons for revision of total knee arthroplasty are loosening and abnormal axial alignment leading to an unphysiological kinematic of the knee implant. To get an idea about the postoperative kinematic of the implant, it is essential to determine the position and orientation of the tibial and femoral prosthesis. Therefore we developed a registration method for fitting 3D CAD-models of knee joint prostheses into an 3D MR image. This rigid registration is the basis for a quantitative analysis of the kinematics of knee implants. Firstly the surface data of the prostheses models are converted into a voxel representation; a recursive algorithm determines all boundary voxels of the original triangular surface data. Secondly an initial preconfiguration of the implants by the user is still necessary for the following step: The user has to perform a rough preconfiguration of both remaining prostheses models, so that the fine matching process gets a reasonable starting point. After that an automated gradient-based fine matching process determines the best absolute position and orientation: This iterative process changes all 6 parameters (3 rotational- and 3 translational parameters) of a model by a minimal amount until a maximum value of the matching function is reached. To examine the spread of the final solutions of the registration, the interobserver variability was measured in a group of testers. This variability, calculated by the relative standard deviation, improved from about 50% (pure manual registration) to 0.5% (rough manual preconfiguration and subsequent fine registration with the automatic fine matching process).

  19. Advanced 3D imaging lidar concepts for long range sensing

    NASA Astrophysics Data System (ADS)

    Gordon, K. J.; Hiskett, P. A.; Lamb, R. A.

    2014-06-01

    Recent developments in 3D imaging lidar are presented. Long range 3D imaging using photon counting is now a possibility, offering a low-cost approach to integrated remote sensing with step changing advantages in size, weight and power compared to conventional analogue active imaging technology. We report results using a Geiger-mode array for time-of-flight, single photon counting lidar for depth profiling and determination of the shape and size of tree canopies and distributed surface reflections at a range of 9km, with 4μJ pulses with a frame rate of 100kHz using a low-cost fibre laser operating at a wavelength of λ=1.5 μm. The range resolution is less than 4cm providing very high depth resolution for target identification. This specification opens up several additional functionalities for advanced lidar, for example: absolute rangefinding and depth profiling for long range identification, optical communications, turbulence sensing and time-of-flight spectroscopy. Future concepts for 3D time-of-flight polarimetric and multispectral imaging lidar, with optical communications in a single integrated system are also proposed.

  20. Image Appraisal for 2D and 3D Electromagnetic Inversion

    SciTech Connect

    Alumbaugh, D.L.; Newman, G.A.

    1999-01-28

    Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and posterior model covariance matrices can be directly calculated. A method to examine how the horizontal and vertical resolution varies spatially within the electromagnetic property image is developed by examining the columns of the model resolution matrix. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how errors in the inversion process such as data noise and incorrect a priori assumptions about the imaged model map into parameter error. This type of image is shown to be useful in analyzing spatial variations in the image sensitivity to the data. A method is analyzed for statistically estimating the model covariance matrix when the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion). A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on 2D and 3D synthetic cross well EM data sets, as well as a field data set collected at the Lost Hills Oil Field in Central California.

  1. Simulating Seismic Wave Propagation in 3-D Structure: A Case Study For Istanbul City

    NASA Astrophysics Data System (ADS)

    Yelkenci, Seda; Aktar, Mustafa

    2013-04-01

    Investigation of the wave propagation around the Marmara Sea, in particular for the city of Istanbul is critical because this target area is identified as one of the megacities with the highest seismic risk in the world. This study makes an attempt for creating an integrated 3D seismic/geologic model and precise understanding of 3-D wave propagation in the city of Istanbul. The approach is based on generating synthetic seismograms using realistic velocity structures as well as accurate location, focal mechanism and source parameters of reference earthquakes. The modarate size reference earthquakes occured in the Marmara Sea and were recorded by the National Seismic Network of Turkey as well as the network of Istanbul Early Warning and Rapid Response System. The seismograms are simulated by means of a 3-D finite difference method operated on parallel processing environment. In the content of creating a robust velocity model; 1D velocity models which are derived fom previous crustal studies of Marmara region such as refraction seismic and receiver functions have been conducted firstly for depths greater than 1km. Velocity structure in shallower part of the study region is then derived from recent geophysical and geotechnical surveys. To construct 3-D model from the obtained 1-D model data, a variety of interpolation methods are considered. According to the observations on amplitude and arrival time based on comparison of simulated seismograms, the considered velocity model is refined the way that S delay times are compensated. Another important task of this work is an application of the finite difference method to estimate three-dimensional seismic responses for a specified basin structure including soft sediments with low shear velocities in respect of the surrounded area in the Asian part of Istanbul. The analysis performed both in the time and frequency domain, helps in understanding of the comprehensive wave propagation characteristics and the distribution of

  2. Right main bronchus perforation detected by 3D-image

    PubMed Central

    Bense, László; Eklund, Gunnar; Jorulf, Hakan; Farkas, Árpád; Balásházy, Imre; Hedenstierna, Göran; Krebsz, Ádám; Madas, Balázs Gergely; Strindberg, Jerker Eden

    2011-01-01

    A male metal worker, who has never smoked, contracted debilitating dyspnoea in 2003 which then deteriorated until 2007. Spirometry and chest x-rays provided no diagnosis. A 3D-image of the airways was reconstructed from a high-resolution CT (HRCT) in 2007, showing peribronchial air on the right side, mostly along the presegmental airways. After digital subtraction of the image of the peribronchial air, a hole on the cranial side of the right main bronchus was detected. The perforation could be identified at the re-examination of HRCTs in 2007 and 2009, but not in 2010 when it had possibly healed. The occupational exposure of the patient to evaporating chemicals might have contributed to the perforation and hampered its healing. A 3D HRCT reconstruction should be considered to detect bronchial anomalies, including wall-perforation, when unexplained dyspnoea or other chest symptoms call for extended investigation. PMID:22679238

  3. Ultra-High Resolution 3D Imaging of Whole Cells.

    PubMed

    Huang, Fang; Sirinakis, George; Allgeyer, Edward S; Schroeder, Lena K; Duim, Whitney C; Kromann, Emil B; Phan, Thomy; Rivera-Molina, Felix E; Myers, Jordan R; Irnov, Irnov; Lessard, Mark; Zhang, Yongdeng; Handel, Mary Ann; Jacobs-Wagner, Christine; Lusk, C Patrick; Rothman, James E; Toomre, Derek; Booth, Martin J; Bewersdorf, Joerg

    2016-08-11

    Fluorescence nanoscopy, or super-resolution microscopy, has become an important tool in cell biological research. However, because of its usually inferior resolution in the depth direction (50-80 nm) and rapidly deteriorating resolution in thick samples, its practical biological application has been effectively limited to two dimensions and thin samples. Here, we present the development of whole-cell 4Pi single-molecule switching nanoscopy (W-4PiSMSN), an optical nanoscope that allows imaging of three-dimensional (3D) structures at 10- to 20-nm resolution throughout entire mammalian cells. We demonstrate the wide applicability of W-4PiSMSN across diverse research fields by imaging complex molecular architectures ranging from bacteriophages to nuclear pores, cilia, and synaptonemal complexes in large 3D cellular volumes. PMID:27397506

  4. 3D scene reconstruction based on 3D laser point cloud combining UAV images

    NASA Astrophysics Data System (ADS)

    Liu, Huiyun; Yan, Yangyang; Zhang, Xitong; Wu, Zhenzhen

    2016-03-01

    It is a big challenge capturing and modeling 3D information of the built environment. A number of techniques and technologies are now in use. These include GPS, and photogrammetric application and also remote sensing applications. The experiment uses multi-source data fusion technology for 3D scene reconstruction based on the principle of 3D laser scanning technology, which uses the laser point cloud data as the basis and Digital Ortho-photo Map as an auxiliary, uses 3DsMAX software as a basic tool for building three-dimensional scene reconstruction. The article includes data acquisition, data preprocessing, 3D scene construction. The results show that the 3D scene has better truthfulness, and the accuracy of the scene meet the need of 3D scene construction.

  5. Automated Recognition of 3D Features in GPIR Images

    NASA Technical Reports Server (NTRS)

    Park, Han; Stough, Timothy; Fijany, Amir

    2007-01-01

    A method of automated recognition of three-dimensional (3D) features in images generated by ground-penetrating imaging radar (GPIR) is undergoing development. GPIR 3D images can be analyzed to detect and identify such subsurface features as pipes and other utility conduits. Until now, much of the analysis of GPIR images has been performed manually by expert operators who must visually identify and track each feature. The present method is intended to satisfy a need for more efficient and accurate analysis by means of algorithms that can automatically identify and track subsurface features, with minimal supervision by human operators. In this method, data from multiple sources (for example, data on different features extracted by different algorithms) are fused together for identifying subsurface objects. The algorithms of this method can be classified in several different ways. In one classification, the algorithms fall into three classes: (1) image-processing algorithms, (2) feature- extraction algorithms, and (3) a multiaxis data-fusion/pattern-recognition algorithm that includes a combination of machine-learning, pattern-recognition, and object-linking algorithms. The image-processing class includes preprocessing algorithms for reducing noise and enhancing target features for pattern recognition. The feature-extraction algorithms operate on preprocessed data to extract such specific features in images as two-dimensional (2D) slices of a pipe. Then the multiaxis data-fusion/ pattern-recognition algorithm identifies, classifies, and reconstructs 3D objects from the extracted features. In this process, multiple 2D features extracted by use of different algorithms and representing views along different directions are used to identify and reconstruct 3D objects. In object linking, which is an essential part of this process, features identified in successive 2D slices and located within a threshold radius of identical features in adjacent slices are linked in a

  6. A 3D Seismic Case: Shooting around a CCS Drill Site

    NASA Astrophysics Data System (ADS)

    Wang, C.

    2013-12-01

    The reduction of carbon dioxide emission to lessen the global warming has become an important international issue in recent years. The CCS technique (Carbon-dioxide Capture and Storage) is among the most recommended methods. The capture of CO2 during its manufacturing process in the electric power plant and storing in the adjacent area is considered to be an economical and feasible choice. This research uses the 2D and 3D high-resolution seismic reflection method to investigate possible CCS sites along the coast in Taiwan. The site is near an electric power plant and is planned to be a CCS experiment laboratory. The main objective is to detect the proper geologic structure and to prepare the baseline data for the future CO2 monitoring. The size of the high-resolution method applied in this study is much smaller than that used in the oil exploration. The obtained high quality and high resolution data can resolve very detailed structures. The survey parameters in 2D are 4m interval, 240 channels. The bin size in 3D seismic is 8m x 4m, 288 channels. Both 2D and 3D used the Minivibe as a source with 40Hz geophones, and having an average of 30 folds. The 3D seismic survey was conducted around the planned drill site. A surrounding type of 3D data acquisition was taken with sources at outside and receivers at the center. Such a deployment design is quite suitable for the drill site investigation. The structural layer as thin as 4m is able to be detected even under a depth of 3000m. Such a high resolution allows us not only to estimate the structure, but also able to monitor the migration of CO 2 after storage. The results of seismic survey after comparing with a nearby borehole data show that : 1) the caprock is Chinshui shale which is at a depth of 880m to 1000m with a thickness about 120m, 2) the Nanchuang formation and Kueichulin formation with high porosity can be proper reservoir layers which are located at the depth between 1000m to 1700m. In conclusion, this site

  7. 3D tongue motion from tagged and cine MR images.

    PubMed

    Xing, Fangxu; Woo, Jonghye; Murano, Emi Z; Lee, Junghoon; Stone, Maureen; Prince, Jerry L

    2013-01-01

    Understanding the deformation of the tongue during human speech is important for head and neck surgeons and speech and language scientists. Tagged magnetic resonance (MR) imaging can be used to image 2D motion, and data from multiple image planes can be combined via post-processing to yield estimates of 3D motion. However, lacking boundary information, this approach suffers from inaccurate estimates near the tongue surface. This paper describes a method that combines two sources of information to yield improved estimation of 3D tongue motion. The method uses the harmonic phase (HARP) algorithm to extract motion from tags and diffeomorphic demons to provide surface deformation. It then uses an incompressible deformation estimation algorithm to incorporate both sources of displacement information to form an estimate of the 3D whole tongue motion. Experimental results show that use of combined information improves motion estimation near the tongue surface, a problem that has previously been reported as problematic in HARP analysis, while preserving accurate internal motion estimates. Results on both normal and abnormal tongue motions are shown. PMID:24505742

  8. Discrete Method of Images for 3D Radio Propagation Modeling

    NASA Astrophysics Data System (ADS)

    Novak, Roman

    2016-09-01

    Discretization by rasterization is introduced into the method of images (MI) in the context of 3D deterministic radio propagation modeling as a way to exploit spatial coherence of electromagnetic propagation for fine-grained parallelism. Traditional algebraic treatment of bounding regions and surfaces is replaced by computer graphics rendering of 3D reflections and double refractions while building the image tree. The visibility of reception points and surfaces is also resolved by shader programs. The proposed rasterization is shown to be of comparable run time to that of the fundamentally parallel shooting and bouncing rays. The rasterization does not affect the signal evaluation backtracking step, thus preserving its advantage over the brute force ray-tracing methods in terms of accuracy. Moreover, the rendering resolution may be scaled back for a given level of scenario detail with only marginal impact on the image tree size. This allows selection of scene optimized execution parameters for faster execution, giving the method a competitive edge. The proposed variant of MI can be run on any GPU that supports real-time 3D graphics.

  9. Radiometric Quality Evaluation of INSAT-3D Imager Data

    NASA Astrophysics Data System (ADS)

    Prakash, S.; Jindal, D.; Badal, N.; Kartikeyan, B.; Gopala Krishna, B.

    2014-11-01

    INSAT-3D is an advanced meteorological satellite of ISRO which acquires imagery in optical and infra-red (IR) channels for study of weather dynamics in Indian sub-continent region. In this paper, methodology of radiometric quality evaluation for Level-1 products of Imager, one of the payloads onboard INSAT-3D, is described. Firstly, overall visual quality of scene in terms of dynamic range, edge sharpness or modulation transfer function (MTF), presence of striping and other image artefacts is computed. Uniform targets in Desert and Sea region are identified for which detailed radiometric performance evaluation for IR channels is carried out. Mean brightness temperature (BT) of targets is computed and validated with independently generated radiometric references. Further, diurnal/seasonal trends in target BT values and radiometric uncertainty or sensor noise are studied. Results of radiometric quality evaluation over duration of eight months (January to August 2014) and comparison of radiometric consistency pre/post yaw flip of satellite are presented. Radiometric Analysis indicates that INSAT-3D images have high contrast (MTF > 0.2) and low striping effects. A bias of <4K is observed in the brightness temperature values of TIR-1 channel measured during January-August 2014 indicating consistent radiometric calibration. Diurnal and seasonal analysis shows that Noise equivalent differential temperature (NEdT) for IR channels is consistent and well within specifications.

  10. Automated Identification of Fiducial Points on 3D Torso Images

    PubMed Central

    Kawale, Manas M; Reece, Gregory P; Crosby, Melissa A; Beahm, Elisabeth K; Fingeret, Michelle C; Markey, Mia K; Merchant, Fatima A

    2013-01-01

    Breast reconstruction is an important part of the breast cancer treatment process for many women. Recently, 2D and 3D images have been used by plastic surgeons for evaluating surgical outcomes. Distances between different fiducial points are frequently used as quantitative measures for characterizing breast morphology. Fiducial points can be directly marked on subjects for direct anthropometry, or can be manually marked on images. This paper introduces novel algorithms to automate the identification of fiducial points in 3D images. Automating the process will make measurements of breast morphology more reliable, reducing the inter- and intra-observer bias. Algorithms to identify three fiducial points, the nipples, sternal notch, and umbilicus, are described. The algorithms used for localization of these fiducial points are formulated using a combination of surface curvature and 2D color information. Comparison of the 3D co-ordinates of automatically detected fiducial points and those identified manually, and geodesic distances between the fiducial points are used to validate algorithm performance. The algorithms reliably identified the location of all three of the fiducial points. We dedicate this article to our late colleague and friend, Dr. Elisabeth K. Beahm. Elisabeth was both a talented plastic surgeon and physician-scientist; we deeply miss her insight and her fellowship. PMID:25288903

  11. Fast 3D fluid registration of brain magnetic resonance images

    NASA Astrophysics Data System (ADS)

    Leporé, Natasha; Chou, Yi-Yu; Lopez, Oscar L.; Aizenstein, Howard J.; Becker, James T.; Toga, Arthur W.; Thompson, Paul M.

    2008-03-01

    Fluid registration is widely used in medical imaging to track anatomical changes, to correct image distortions, and to integrate multi-modality data. Fluid mappings guarantee that the template image deforms smoothly into the target, without tearing or folding, even when large deformations are required for accurate matching. Here we implemented an intensity-based fluid registration algorithm, accelerated by using a filter designed by Bro-Nielsen and Gramkow. We validated the algorithm on 2D and 3D geometric phantoms using the mean square difference between the final registered image and target as a measure of the accuracy of the registration. In tests on phantom images with different levels of overlap, varying amounts of Gaussian noise, and different intensity gradients, the fluid method outperformed a more commonly used elastic registration method, both in terms of accuracy and in avoiding topological errors during deformation. We also studied the effect of varying the viscosity coefficients in the viscous fluid equation, to optimize registration accuracy. Finally, we applied the fluid registration algorithm to a dataset of 2D binary corpus callosum images and 3D volumetric brain MRIs from 14 healthy individuals to assess its accuracy and robustness.

  12. Training toward Advanced 3D Seismic Methods for CO2 Monitoring, Verification, and Accounting

    SciTech Connect

    Christopher Liner

    2012-05-31

    The objective of our work is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO{sub 2}, specifically better quantification and sensitivity for mapping of caprock integrity, fractures, and other potential leakage pathways. We utilize data and results developed through previous DOE-funded CO{sub 2} characterization project (DE-FG26-06NT42734) at the Dickman Field of Ness County, KS. Dickman is a type locality for the geology that will be encountered for CO{sub 2} sequestration projects from northern Oklahoma across the U.S. midcontinent to Indiana and Illinois. Since its discovery in 1962, the Dickman Field has produced about 1.7 million barrels of oil from porous Mississippian carbonates with a small structural closure at about 4400 ft drilling depth. Project data includes 3.3 square miles of 3D seismic data, 142 wells, with log, some core, and oil/water production data available. Only two wells penetrate the deep saline aquifer. In a previous DOE-funded project, geological and seismic data were integrated to create a geological property model and a flow simulation grid. We believe that sequestration of CO{sub 2} will largely occur in areas of relatively flat geology and simple near surface, similar to Dickman. The challenge is not complex geology, but development of improved, lower-cost methods for detecting natural fractures and subtle faults. Our project used numerical simulation to test methods of gathering multicomponent, full azimuth data ideal for this purpose. Our specific objectives were to apply advanced seismic methods to aide in quantifying reservoir properties and lateral continuity of CO{sub 2} sequestration targets. The purpose of the current project is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO{sub 2

  13. Femoroacetabular impingement with chronic acetabular rim fracture - 3D computed tomography, 3D magnetic resonance imaging and arthroscopic correlation

    PubMed Central

    Chhabra, Avneesh; Nordeck, Shaun; Wadhwa, Vibhor; Madhavapeddi, Sai; Robertson, William J

    2015-01-01

    Femoroacetabular impingement is uncommonly associated with a large rim fragment of bone along the superolateral acetabulum. We report an unusual case of femoroacetabular impingement (FAI) with chronic acetabular rim fracture. Radiographic, 3D computed tomography, 3D magnetic resonance imaging and arthroscopy correlation is presented with discussion of relative advantages and disadvantages of various modalities in the context of FAI. PMID:26191497

  14. Stereotactic mammography imaging combined with 3D US imaging for image guided breast biopsy

    SciTech Connect

    Surry, K. J. M.; Mills, G. R.; Bevan, K.; Downey, D. B.; Fenster, A.

    2007-11-15

    Stereotactic X-ray mammography (SM) and ultrasound (US) guidance are both commonly used for breast biopsy. While SM provides three-dimensional (3D) targeting information and US provides real-time guidance, both have limitations. SM is a long and uncomfortable procedure and the US guided procedure is inherently two dimensional (2D), requiring a skilled physician for both safety and accuracy. The authors developed a 3D US-guided biopsy system to be integrated with, and to supplement SM imaging. Their goal is to be able to biopsy a larger percentage of suspicious masses using US, by clarifying ambiguous structures with SM imaging. Features from SM and US guided biopsy were combined, including breast stabilization, a confined needle trajectory, and dual modality imaging. The 3D US guided biopsy system uses a 7.5 MHz breast probe and is mounted on an upright SM machine for preprocedural imaging. Intraprocedural targeting and guidance was achieved with real-time 2D and near real-time 3D US imaging. Postbiopsy 3D US imaging allowed for confirmation that the needle was penetrating the target. The authors evaluated 3D US-guided biopsy accuracy of their system using test phantoms. To use mammographic imaging information, they registered the SM and 3D US coordinate systems. The 3D positions of targets identified in the SM images were determined with a target localization error (TLE) of 0.49 mm. The z component (x-ray tube to image) of the TLE dominated with a TLE{sub z} of 0.47 mm. The SM system was then registered to 3D US, with a fiducial registration error (FRE) and target registration error (TRE) of 0.82 and 0.92 mm, respectively. Analysis of the FRE and TRE components showed that these errors were dominated by inaccuracies in the z component with a FRE{sub z} of 0.76 mm and a TRE{sub z} of 0.85 mm. A stereotactic mammography and 3D US guided breast biopsy system should include breast compression for stability and safety and dual modality imaging for target localization

  15. Pavement cracking measurements using 3D laser-scan images

    NASA Astrophysics Data System (ADS)

    Ouyang, W.; Xu, B.

    2013-10-01

    Pavement condition surveying is vital for pavement maintenance programs that ensure ride quality and traffic safety. This paper first introduces an automated pavement inspection system which uses a three-dimensional (3D) camera and a structured laser light to acquire dense transverse profiles of a pavement lane surface when it carries a moving vehicle. After the calibration, the 3D system can yield a depth resolution of 0.5 mm and a transverse resolution of 1.56 mm pixel-1 at 1.4 m camera height from the ground. The scanning rate of the camera can be set to its maximum at 5000 lines s-1, allowing the density of scanned profiles to vary with the vehicle's speed. The paper then illustrates the algorithms that utilize 3D information to detect pavement distress, such as transverse, longitudinal and alligator cracking, and presents the field tests on the system's repeatability when scanning a sample pavement in multiple runs at the same vehicle speed, at different vehicle speeds and under different weather conditions. The results show that this dedicated 3D system can capture accurate pavement images that detail surface distress, and obtain consistent crack measurements in repeated tests and under different driving and lighting conditions.

  16. 3D Seismic Studies of Igneous Intrusions, Taranaki Basin, off-shore west New Zealand

    NASA Astrophysics Data System (ADS)

    Harbor, R. L.; Chrisitiansen, E. H.; Keach, R. W.

    2008-12-01

    Several off-shore volcano-plutonic complexes are imaged in a detailed 3D seismic survey acquired by Pogo New Zealand/Plains Exploration. The new data provide insight into the sizes, shapes, and wall rock deformation associated with the emplacement of plutons. The seismic survey, conducted in 2005, covers 1700 km2 and was processed with modern techniques used in hydrocarbon exploration. The images and structures have to be interpreted with care because of distortions caused by "velocity pull ups" created by the large seismic wave velocity contrast between sediment and igneous rock. The magmatic rocks may be part of the Mohakatino Volcanic Centre (15 to 1.5 Ma) that intrudes and partially fills the Taranaki graben, which began to form in the Cretaceous. Imaged plutons range from less than 1 to as much as 12 km across. The intrusions are steep-sided and do not resemble sills, but their bases are poorly resolved. The top of the largest complex is sharply delineated and marked by multiple apophyses as much as 2 km across and hundreds of meters high. Deformation along the sides of the intrusion is dominated by of a faulted rim anticline, with apparent dips of 45° or higher. Dips decrease rapidly away from the intrusion but doming extends several hundred meters from the margins. A series of high-angle faults fan out from the margin of the pluton and cut the folded strata along the margin. These faults terminate against the margins of the intrusion, extend as much as 1 pluton diameter away from the margin, and then merge with "regional" faults that are part of the Taranaki graben. Offset along these radiating faults is on the order of a few hundred meters. Strata on the top of the complex are thinned but are deformed into a faulted dome with an amplitude of about 1 km. Steep, dip-slip faults form a semi-radial pattern in the roof rocks but are strongly controlled by the regional stress field as many of the faults are sub-parallel to those that form the graben. The longest

  17. Triangulation Based 3D Laser Imaging for Fracture Orientation Analysis

    NASA Astrophysics Data System (ADS)

    Mah, J.; Claire, S.; Steve, M.

    2009-05-01

    Laser imaging has recently been identified as a potential tool for rock mass characterization. This contribution focuses on the application of triangulation based, short-range laser imaging to determine fracture orientation and surface texture. This technology measures the distance to the target by triangulating the projected and reflected laser beams, and also records the reflection intensity. In this study, we acquired 3D laser images of rock faces using the Laser Camera System (LCS), a portable instrument developed by Neptec Design Group (Ottawa, Canada). The LCS uses an infrared laser beam and is immune to the lighting conditions. The maximum image resolution is 1024 x 1024 volumetric image elements. Depth resolution is 0.5 mm at 5 m. An above ground field trial was conducted at a blocky road cut with well defined joint sets (Kingston, Ontario). An underground field trial was conducted at the Inco 175 Ore body (Sudbury, Ontario) where images were acquired in the dark and the joint set features were more subtle. At each site, from a distance of 3 m away from the rock face, a grid of six images (approximately 1.6 m by 1.6 m) was acquired at maximum resolution with 20% overlap between adjacent images. This corresponds to a density of 40 image elements per square centimeter. Polyworks, a high density 3D visualization software tool, was used to align and merge the images into a single digital triangular mesh. The conventional method of determining fracture orientations is by manual measurement using a compass. In order to be accepted as a substitute for this method, the LCS should be capable of performing at least to the capabilities of manual measurements. To compare fracture orientation estimates derived from the 3D laser images to manual measurements, 160 inclinometer readings were taken at the above ground site. Three prominent joint sets (strike/dip: 236/09, 321/89, 325/01) were identified by plotting the joint poles on a stereonet. Underground, two main joint

  18. 3D seismic data reconstruction based on complex-valued curvelet transform in frequency domain

    NASA Astrophysics Data System (ADS)

    Zhang, Hua; Chen, Xiaohong; Li, Hongxing

    2015-02-01

    Traditional seismic data sampling must follow the Nyquist Sampling Theorem. However, the field data acquisition may not meet the sampling criteria due to missing traces or limits in exploration cost, causing a prestack data reconstruction problem. Recently researchers have proposed many useful methods to regularize the seismic data. In this paper, a 3D seismic data reconstruction method based on the Projections Onto Convex Sets (POCS) algorithm and a complex-valued curvelet transform (CCT) has been introduced in the frequency domain. In order to improve reconstruction efficiency and reduce the computation time, the seismic data are transformed from the t-x-y domain to the f-x-y domain and the data reconstruction is processed for every frequency slice during the reconstruction process. The selection threshold parameter is important for reconstruction efficiency for each iteration, therefore an exponential square root decreased (ESRD) threshold is proposed. The experimental results show that the ESRD threshold can greatly reduce iterations and improve reconstruction efficiency compared to the other thresholds for the same reconstruction result. We also analyze the antinoise ability of the CCT-based POCS reconstruction method. The example studies on synthetic and real marine seismic data showed that our proposed method is more efficient and applicable.

  19. Virtual image display as a backlight for 3D.

    PubMed

    Travis, Adrian; MacCrann, Niall; Emerton, Neil; Kollin, Joel; Georgiou, Andreas; Lanier, Jaron; Bathiche, Stephen

    2013-07-29

    We describe a device which has the potential to be used both as a virtual image display and as a backlight. The pupil of the emitted light fills the device approximately to its periphery and the collimated emission can be scanned both horizontally and vertically in the manner needed to illuminate an eye in any position. The aim is to reduce the power needed to illuminate a liquid crystal panel but also to enable a smooth transition from 3D to a virtual image as the user nears the screen. PMID:23938645

  20. 3D imaging of soil pore network: two different approaches

    NASA Astrophysics Data System (ADS)

    Matrecano, M.; Di Matteo, B.; Mele, G.; Terribile, F.

    2009-04-01

    Pore geometry imaging and its quantitative description is a key factor for advances in the knowledge of physical, chemical and biological soil processes. For many years photos from flattened surfaces of undisturbed soil samples impregnated with fluorescent resin and from soil thin sections under microscope have been the only way available for exploring pore architecture at different scales. Earlier 3D representations of the internal structure of the soil based on not destructive methods have been obtained using medical tomographic systems (NMR and X-ray CT). However, images provided using such equipments, show strong limitations in terms of spatial resolution. In the last decade very good results have then been obtained using imaging from very expensive systems based on synchrotron radiation. More recently, X-ray Micro-Tomography has resulted the most widely applied being the technique showing the best compromise between costs, resolution and size of the images. Conversely, the conceptually simpler but destructive method of "serial sectioning" has been progressively neglected for technical problems in sample preparation and time consumption needed to obtain an adequate number of serial sections for correct 3D reconstruction of soil pore geometry. In this work a comparison between the two methods above has been carried out in order to define advantages, shortcomings and to point out their different potential. A cylindrical undisturbed soil sample 6.5cm in diameter and 6.5cm height of an Ap horizon of an alluvial soil showing vertic characteristics, has been reconstructed using both a desktop X-ray micro-tomograph Skyscan 1172 and the new automatic serial sectioning system SSAT (Sequential Section Automatic Tomography) set up at CNR ISAFOM in Ercolano (Italy) with the aim to overcome most of the typical limitations of such a technique. Image best resolution of 7.5 µm per voxel resulted using X-ray Micro CT while 20 µm was the best value using the serial sectioning

  1. Automating Shallow Seismic Imaging

    SciTech Connect

    Steeples, Don W.

    2004-12-09

    This seven-year, shallow-seismic reflection research project had the aim of improving geophysical imaging of possible contaminant flow paths. Thousands of chemically contaminated sites exist in the United States, including at least 3,700 at Department of Energy (DOE) facilities. Imaging technologies such as shallow seismic reflection (SSR) and ground-penetrating radar (GPR) sometimes are capable of identifying geologic conditions that might indicate preferential contaminant-flow paths. Historically, SSR has been used very little at depths shallower than 30 m, and even more rarely at depths of 10 m or less. Conversely, GPR is rarely useful at depths greater than 10 m, especially in areas where clay or other electrically conductive materials are present near the surface. Efforts to image the cone of depression around a pumping well using seismic methods were only partially successful (for complete references of all research results, see the full Final Technical Report, DOE/ER/14826-F), but peripheral results included development of SSR methods for depths shallower than one meter, a depth range that had not been achieved before. Imaging at such shallow depths, however, requires geophone intervals of the order of 10 cm or less, which makes such surveys very expensive in terms of human time and effort. We also showed that SSR and GPR could be used in a complementary fashion to image the same volume of earth at very shallow depths. The primary research focus of the second three-year period of funding was to develop and demonstrate an automated method of conducting two-dimensional (2D) shallow-seismic surveys with the goal of saving time, effort, and money. Tests involving the second generation of the hydraulic geophone-planting device dubbed the ''Autojuggie'' showed that large numbers of geophones can be placed quickly and automatically and can acquire high-quality data, although not under rough topographic conditions. In some easy-access environments, this device could

  2. Automatic structural matching of 3D image data

    NASA Astrophysics Data System (ADS)

    Ponomarev, Svjatoslav; Lutsiv, Vadim; Malyshev, Igor

    2015-10-01

    A new image matching technique is described. It is implemented as an object-independent hierarchical structural juxtaposition algorithm based on an alphabet of simple object-independent contour structural elements. The structural matching applied implements an optimized method of walking through a truncated tree of all possible juxtapositions of two sets of structural elements. The algorithm was initially developed for dealing with 2D images such as the aerospace photographs, and it turned out to be sufficiently robust and reliable for matching successfully the pictures of natural landscapes taken in differing seasons from differing aspect angles by differing sensors (the visible optical, IR, and SAR pictures, as well as the depth maps and geographical vector-type maps). At present (in the reported version), the algorithm is enhanced based on additional use of information on third spatial coordinates of observed points of object surfaces. Thus, it is now capable of matching the images of 3D scenes in the tasks of automatic navigation of extremely low flying unmanned vehicles or autonomous terrestrial robots. The basic principles of 3D structural description and matching of images are described, and the examples of image matching are presented.

  3. Mesh generation from 3D multi-material images.

    PubMed

    Boltcheva, Dobrina; Yvinec, Mariette; Boissonnat, Jean-Daniel

    2009-01-01

    The problem of generating realistic computer models of objects represented by 3D segmented images is important in many biomedical applications. Labelled 3D images impose particular challenges for meshing algorithms because multi-material junctions form features such as surface pacthes, edges and corners which need to be preserved into the output mesh. In this paper, we propose a feature preserving Delaunay refinement algorithm which can be used to generate high-quality tetrahedral meshes from segmented images. The idea is to explicitly sample corners and edges from the input image and to constrain the Delaunay refinement algorithm to preserve these features in addition to the surface patches. Our experimental results on segmented medical images have shown that, within a few seconds, the algorithm outputs a tetrahedral mesh in which each material is represented as a consistent submesh without gaps and overlaps. The optimization property of the Delaunay triangulation makes these meshes suitable for the purpose of realistic visualization or finite element simulations. PMID:20426123

  4. Underwater 3d Modeling: Image Enhancement and Point Cloud Filtering

    NASA Astrophysics Data System (ADS)

    Sarakinou, I.; Papadimitriou, K.; Georgoula, O.; Patias, P.

    2016-06-01

    This paper examines the results of image enhancement and point cloud filtering on the visual and geometric quality of 3D models for the representation of underwater features. Specifically it evaluates the combination of effects from the manual editing of images' radiometry (captured at shallow depths) and the selection of parameters for point cloud definition and mesh building (processed in 3D modeling software). Such datasets, are usually collected by divers, handled by scientists and used for geovisualization purposes. In the presented study, have been created 3D models from three sets of images (seafloor, part of a wreck and a small boat's wreck) captured at three different depths (3.5m, 10m and 14m respectively). Four models have been created from the first dataset (seafloor) in order to evaluate the results from the application of image enhancement techniques and point cloud filtering. The main process for this preliminary study included a) the definition of parameters for the point cloud filtering and the creation of a reference model, b) the radiometric editing of images, followed by the creation of three improved models and c) the assessment of results by comparing the visual and the geometric quality of improved models versus the reference one. Finally, the selected technique is tested on two other data sets in order to examine its appropriateness for different depths (at 10m and 14m) and different objects (part of a wreck and a small boat's wreck) in the context of an ongoing research in the Laboratory of Photogrammetry and Remote Sensing.

  5. Probabilistic Seismic Hazard Maps for Seattle, Washington, Based on 3D Ground-Motion Simulations

    NASA Astrophysics Data System (ADS)

    Frankel, A. D.; Stephenson, W. J.; Carver, D. L.; Williams, R. A.; Odum, J. K.; Rhea, S.

    2007-12-01

    We have produced probabilistic seismic hazard maps for Seattle using over 500 3D finite-difference simulations of ground motions from earthquakes in the Seattle fault zone, Cascadia subduction zone, South Whidbey Island fault, and background shallow and deep source areas. The maps depict 1 Hz response spectral accelerations with 2, 5, and 10% probabilities of being exceeded in 50 years. The simulations were used to generate site and source dependent amplification factors that are applied to rock-site attenuation relations. The maps incorporate essentially the same fault sources and earthquake recurrence times as the 2002 national seismic hazard maps. The simulations included basin surface waves and basin-edge focusing effects from a 3D model of the Seattle basin. The 3D velocity model was validated by modeling several earthquakes in the region, including the 2001 M6.8 Nisqually earthquake, that were recorded by our Seattle Urban Seismic Network and the Pacific Northwest Seismic Network. The simulations duplicate our observation that earthquakes from the south and southwest typically produce larger amplifications in the Seattle basin than earthquakes from other azimuths, relative to rock sites outside the basin. Finite-fault simulations were run for earthquakes along the Seattle fault zone, with magnitudes ranging from 6.6 to 7.2, so that the effects of rupture directivity were included. Nonlinear amplification factors for soft-soil sites of fill and alluvium were also applied in the maps. For the Cascadia subduction zone, 3D simulations with point sources at different locations along the zone were used to determine amplification factors across Seattle expected for great subduction-zone earthquakes. These new urban seismic hazard maps are based on determinations of hazard for 7236 sites with a spacing of 280 m. The maps show that the highest hazard locations for this frequency band (around 1 Hz) are soft-soil sites (fill and alluvium) within the Seattle basin and

  6. 3D Numerical Simulation on the Sloshing Waves Excited by the Seismic Shacking

    NASA Astrophysics Data System (ADS)

    Zhang, Lin; Wu, Tso-Ren

    2016-04-01

    In the event of 2015 Nepal earthquake, a video clip broadcasted worldwide showed a violent water spilling in a hotel swimming pool. This sloshing phenomenon indicates a potential water loss in the sensitive facilities, e.g. the spent fuel pools in nuclear power plant, has to be taken into account carefully under the consideration of seismic-induced ground acceleration. In the previous studies, the simulation of sloshing mainly focused on the pressure force on the structure by using a simplified Spring-Mass Method developed in the field of solid mechanics. However, restricted by the assumptions of plane water surface and limited wave height, significant error will be made in evaluating the amount of water loss in the tank. In this paper, the computational fluid dynamical model, Splash3D, was adopted for studying the sloshing problem accurately. Splash3D solved 3D Navier-Stokes Equation directly with Large-Eddy Simulation (LES) turbulent closure. The Volume-of-fluid (VOF) method with piecewise linear interface calculation (PLIC) was used to track the complex breaking water surface. The time series acceleration of a design seismic was loaded to excite the water. With few restrictions from the assumptions, the accuracy of the simulation results were improved dramatically. A series model validations were conducted by compared to a 2D theoretical solution, and a 3D experimental data. Good comparisons can be seen. After the validation, we performed the simulation for considering a sloshing case in a rectangular water tank with a dimension of 12 m long, 8 m wide, 8 m deep, which contained water with 7 m in depth. The seismic movement was imported by considering time-series acceleration in three dimensions, which were about 0.5 g to 1.2 g in the horizontal directions, and 0.3 g to 1 g in the vertical direction. We focused the discussions on the kinematics of the water surface, wave breaking, velocity field, pressure field, water force on the side walls, and, most

  7. Towards magnetic 3D x-ray imaging

    NASA Astrophysics Data System (ADS)

    Fischer, Peter; Streubel, R.; Im, M.-Y.; Parkinson, D.; Hong, J.-I.; Schmidt, O. G.; Makarov, D.

    2014-03-01

    Mesoscale phenomena in magnetism will add essential parameters to improve speed, size and energy efficiency of spin driven devices. Multidimensional visualization techniques will be crucial to achieve mesoscience goals. Magnetic tomography is of large interest to understand e.g. interfaces in magnetic multilayers, the inner structure of magnetic nanocrystals, nanowires or the functionality of artificial 3D magnetic nanostructures. We have developed tomographic capabilities with magnetic full-field soft X-ray microscopy combining X-MCD as element specific magnetic contrast mechanism, high spatial and temporal resolution due to the Fresnel zone plate optics. At beamline 6.1.2 at the ALS (Berkeley CA) a new rotation stage allows recording an angular series (up to 360 deg) of high precision 2D projection images. Applying state-of-the-art reconstruction algorithms it is possible to retrieve the full 3D structure. We will present results on prototypic rolled-up Ni and Co/Pt tubes and glass capillaries coated with magnetic films and compare to other 3D imaging approaches e.g. in electron microscopy. Supported by BES MSD DOE Contract No. DE-AC02-05-CH11231 and ERC under the EU FP7 program (grant agreement No. 306277).

  8. Feature detection on 3D images of dental imprints

    NASA Astrophysics Data System (ADS)

    Mokhtari, Marielle; Laurendeau, Denis

    1994-09-01

    A computer vision approach for the extraction of feature points on 3D images of dental imprints is presented. The position of feature points are needed for the measurement of a set of parameters for automatic diagnosis of malocclusion problems in orthodontics. The system for the acquisition of the 3D profile of the imprint, the procedure for the detection of the interstices between teeth, and the approach for the identification of the type of tooth are described, as well as the algorithm for the reconstruction of the surface of each type of tooth. A new approach for the detection of feature points, called the watershed algorithm, is described in detail. The algorithm is a two-stage procedure which tracks the position of local minima at four different scales and produces a final map of the position of the minima. Experimental results of the application of the watershed algorithm on actual 3D images of dental imprints are presented for molars, premolars and canines. The segmentation approach for the analysis of the shape of incisors is also described in detail.

  9. Variations in axial magma lens properties along the East Pacific Rise (9°30'N-10°00'N) from swath 3-D seismic imaging and 1-D waveform inversion

    NASA Astrophysics Data System (ADS)

    Xu, Min; Pablo Canales, J.; Carbotte, Suzanne M.; Carton, Helene; Nedimović, Mladen R.; Mutter, John C.

    2014-04-01

    We use three-dimensional multistreamer seismic reflection data to investigate variations in axial magma lens (AML) physical properties along the East Pacific Rise between 9°30'N and 10°00'N. Using partial-offset stacks of P- and S-converted waves reflecting off the top of the AML, we image four 2-4 km long melt-rich sections spaced 5-10 km from each other. One-dimensional waveform inversion indicates that the AML in a melt-rich section is best modeled with a low Vp (2.95-3.23 km/s) and Vs (0.3-1.5 km/s), indicating >70% melt fraction. In contrast, the AML in a melt-poor section requires higher Vp (4.52-4.82 km/s) and Vs (2.0-3.0 km/s), which indicates <40% melt fraction. The thicknesses of the AML are constrained to be 8-32 m and 8-120 m at the melt-rich and -poor sites, respectively. Based on the AML melt-mush segmentation imaged in the area around the 2005-2006 eruption, we infer that the main source of this eruption was a 5 km long section of the AML between 9°48'N and 51'N. The eruption drained most of the melt in this section of the AML, leaving behind a large fraction of connected crystals. We estimate that during the 2005-2006 eruption, a total magma volume of 9-83 × 106 m3 was extracted from the AML, with a maximum of 71 × 106 m3 left unerupted in the crust as dikes. From this, we conclude that an eruption of similar dimensions to the 2005-2006, one would be needed with a frequency of years to decades in order to sustain the long-term average seafloor spreading rate at this location.

  10. Detection of ancient morphology and potential hydrocarbon traps using 3-D seismic data and attribute analysis

    SciTech Connect

    Heggland, R.

    1995-12-31

    This paper presents the use of seismic attributes on 3D data to reveal Tertiary and Cretaceous geological features in Norwegian block 9/2. Some of the features would hardly be possible to map using only 2D seismic data. The method which involves a precise interpretation of horizons, attribute analysis and manipulation of colour displays, may be useful when studying morphology, faults and hydrocarbon traps. The interval of interest in this study was from 0 to 1.5 s TWT. Horizontal displays (timeslices and attribute maps), seemed to highlight very nicely geological features such as shallow channels, fractures, karst topography and faults. The attributes used for mapping these features were amplitude, total reflection energy (a volume or time interval attribute), dip and azimuth. The choice of colour scale and manipulation of colour displays were also critical for the results. The data examples clearly demonstrate how it is possible to achieve a very detailed mapping of geological features using 3D seismic data and attribute analysis. The results of this study were useful for the understanding of hydrocarbon migration paths and hydrocarbon traps.

  11. Seismic response of 3D steel buildings considering the effect of PR connections and gravity frames.

    PubMed

    Reyes-Salazar, Alfredo; Bojórquez, Edén; Haldar, Achintya; López-Barraza, Arturo; Rivera-Salas, J Luz

    2014-01-01

    The nonlinear seismic responses of 3D steel buildings with perimeter moment resisting frames (PMRF) and interior gravity frames (IGF) are studied explicitly considering the contribution of the IGF. The effect on the structural response of the stiffness of the beam-to-column connections of the IGF, which is usually neglected, is also studied. It is commonly believed that the flexibility of shear connections is negligible and that 2D models can be used to properly represent 3D real structures. The results of the study indicate, however, that the moments developed on columns of IGF can be considerable and that modeling buildings as plane frames may result in very conservative designs. The contribution of IGF to the lateral structural resistance may be significant. The contribution increases when their connections are assumed to be partially restrained (PR). The incremented participation of IGF when the stiffness of their connections is considered helps to counteract the no conservative effect that results in practice when lateral seismic loads are not considered in IGF while designing steel buildings with PMRF. Thus, if the structural system under consideration is used, the three-dimensional model should be used in seismic analysis and the IGF and the stiffness of their connections should be considered as part of the lateral resistance system. PMID:24995357

  12. Seismic Response of 3D Steel Buildings considering the Effect of PR Connections and Gravity Frames

    PubMed Central

    Haldar, Achintya; López-Barraza, Arturo; Rivera-Salas, J. Luz

    2014-01-01

    The nonlinear seismic responses of 3D steel buildings with perimeter moment resisting frames (PMRF) and interior gravity frames (IGF) are studied explicitly considering the contribution of the IGF. The effect on the structural response of the stiffness of the beam-to-column connections of the IGF, which is usually neglected, is also studied. It is commonly believed that the flexibility of shear connections is negligible and that 2D models can be used to properly represent 3D real structures. The results of the study indicate, however, that the moments developed on columns of IGF can be considerable and that modeling buildings as plane frames may result in very conservative designs. The contribution of IGF to the lateral structural resistance may be significant. The contribution increases when their connections are assumed to be partially restrained (PR). The incremented participation of IGF when the stiffness of their connections is considered helps to counteract the no conservative effect that results in practice when lateral seismic loads are not considered in IGF while designing steel buildings with PMRF. Thus, if the structural system under consideration is used, the three-dimensional model should be used in seismic analysis and the IGF and the stiffness of their connections should be considered as part of the lateral resistance system. PMID:24995357

  13. Fluid flow pathways study from the 3D seismic data offshore southwestern Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, L.; Chi, W. C.; Chiang, H. T.; Lin, S.

    2014-12-01

    3D seismic reflection data provide detailed information on the physical properties of the crust, which can be used for hydrocarbon exploration. Recently, scientists from Taiwan and Germany are collaborating on a project to use a portable 3D seismic system, called P-Cable, to study gas hydrates offshore southwest Taiwan. We have collected 3 cubes, covering the active and passive margins. At these three sites, there is a wide-spread bottom-simulating reflector (BSR). We use the BSR to study the shallow thermal structures of these prospect sites, and use the temperature field information to study fluid migration patterns. We have also done in-situ heat flow measurements, and found similar results, showing focused fluid flow migrations in some pathways. Some of the high temperature fields also correlate with gas chimneys found through seismic attribute analyses. Preliminary results show that there might be active fluid migration above the BSR in the gas hydrate stability zone. In September and October of 2014, we will collect additional P-Cable datasets to be incorporated into this study. Such results will be used to evaluate some proposed sites for future drilling programs.

  14. Performance prediction for 3D filtering of multichannel images

    NASA Astrophysics Data System (ADS)

    Rubel, Oleksii; Kozhemiakin, Ruslan A.; Abramov, Sergey K.; Lukin, Vladimir V.; Vozel, Benoit; Chehdi, Kacem

    2015-10-01

    Performance of denoising based on discrete cosine transform applied to multichannel remote sensing images corrupted by additive white Gaussian noise is analyzed. Images obtained by satellite Earth Observing-1 (EO-1) mission using hyperspectral imager instrument (Hyperion) that have high input SNR are taken as test images. Denoising performance is characterized by improvement of PSNR. For hard-thresholding 3D DCT-based denoising, simple statistics (probabilities to be less than a certain threshold) are used to predict denoising efficiency using curves fitted into scatterplots. It is shown that the obtained curves (approximations) provide prediction of denoising efficiency with high accuracy. Analysis is carried out for different numbers of channels processed jointly. Universality of prediction for different number of channels is proven.

  15. 3D Lunar Terrain Reconstruction from Apollo Images

    NASA Technical Reports Server (NTRS)

    Broxton, Michael J.; Nefian, Ara V.; Moratto, Zachary; Kim, Taemin; Lundy, Michael; Segal, Alkeksandr V.

    2009-01-01

    Generating accurate three dimensional planetary models is becoming increasingly important as NASA plans manned missions to return to the Moon in the next decade. This paper describes a 3D surface reconstruction system called the Ames Stereo Pipeline that is designed to produce such models automatically by processing orbital stereo imagery. We discuss two important core aspects of this system: (1) refinement of satellite station positions and pose estimates through least squares bundle adjustment; and (2) a stochastic plane fitting algorithm that generalizes the Lucas-Kanade method for optimal matching between stereo pair images.. These techniques allow us to automatically produce seamless, highly accurate digital elevation models from multiple stereo image pairs while significantly reducing the influence of image noise. Our technique is demonstrated on a set of 71 high resolution scanned images from the Apollo 15 mission

  16. Phase Sensitive Cueing for 3D Objects in Overhead Images

    SciTech Connect

    Paglieroni, D W; Eppler, W G; Poland, D N

    2005-02-18

    A 3D solid model-aided object cueing method that matches phase angles of directional derivative vectors at image pixels to phase angles of vectors normal to projected model edges is described. It is intended for finding specific types of objects at arbitrary position and orientation in overhead images, independent of spatial resolution, obliqueness, acquisition conditions, and type of imaging sensor. It is shown that the phase similarity measure can be efficiently evaluated over all combinations of model position and orientation using the FFT. The highest degree of similarity over all model orientations is captured in a match surface of similarity values vs. model position. Unambiguous peaks in this surface are sorted in descending order of similarity value, and the small image thumbnails that contain them are presented to human analysts for inspection in sorted order.

  17. Scattering robust 3D reconstruction via polarized transient imaging.

    PubMed

    Wu, Rihui; Suo, Jinli; Dai, Feng; Zhang, Yongdong; Dai, Qionghai

    2016-09-01

    Reconstructing 3D structure of scenes in the scattering medium is a challenging task with great research value. Existing techniques often impose strong assumptions on the scattering behaviors and are of limited performance. Recently, a low-cost transient imaging system has provided a feasible way to resolve the scene depth, by detecting the reflection instant on the time profile of a surface point. However, in cases with scattering medium, the rays are both reflected and scattered during transmission, and the depth calculated from the time profile largely deviates from the true value. To handle this problem, we used the different polarization behaviors of the reflection and scattering components, and introduced active polarization to separate the reflection component to estimate the scattering robust depth. Our experiments have demonstrated that our approach can accurately reconstruct the 3D structure underlying the scattering medium. PMID:27607944

  18. The 3D model control of image processing

    NASA Technical Reports Server (NTRS)

    Nguyen, An H.; Stark, Lawrence

    1989-01-01

    Telerobotics studies remote control of distant robots by a human operator using supervisory or direct control. Even if the robot manipulators has vision or other senses, problems arise involving control, communications, and delay. The communication delays that may be expected with telerobots working in space stations while being controlled from an Earth lab have led to a number of experiments attempting to circumvent the problem. This delay in communication is a main motivating factor in moving from well understood instantaneous hands-on manual control to less well understood supervisory control; the ultimate step would be the realization of a fully autonomous robot. The 3-D model control plays a crucial role in resolving many conflicting image processing problems that are inherent in resolving in the bottom-up approach of most current machine vision processes. The 3-D model control approach is also capable of providing the necessary visual feedback information for both the control algorithms and for the human operator.

  19. The structure of Nevada`s Grant Canyon and Bacon Flat oil fields from 3-D seismic data

    SciTech Connect

    Johnson, E.H.; Zwart, D.W.

    1995-06-01

    The 20 million barrel Grant Canyon structure and its satellite feature, the one million barrel Bacon Flat field, are located at the eastern edge of Railroad Valley, Nevada. Utilizing an eleven square mile 3-D seismic survey, we have unraveled the complicated structure of the field area. The seismic data were calibrated to known geology with 21 wells drilled prior to the 1993 3-D survey, and 4 recent wells. The 3-D data cube provided vertical 2-D seismic lines every 60 feet. Horizontal slices of the data cube rendered {open_quotes}map views{close_quotes} of the structural trends. Still, the interpretation of this complex area was difficult, hampered by extreme velocity variations in the valley fill sediments that degraded data resolution and skewed the imaged structures. The Grant Canyon and Bacon Flat reservoirs are shown to be remnants of detached Devonian rocks that rest upon a northwest-trending salient of younger Paleozoic rocks. The Paleozoic rocks that form the salient are truncated to the southeast against the Troy Intrusive. Beneath the salient, the flank of the intrusive dips about 30 degrees northwest. We show Bacon Flat to be an isolated closure northwest of Grant Canyon field. However, on the south flank of the Grant Canyon reservoir, a significant oil accumulation was trapped on the down side of a normal fault, 400 feet low to the oil column of the field. This appears to be anomalous for a carbonate reservoir with extraordinary permeability, but suggests that more oil may be trapped in the area, on the flanks of producing structures.

  20. 3D range scan enhancement using image-based methods

    NASA Astrophysics Data System (ADS)

    Herbort, Steffen; Gerken, Britta; Schugk, Daniel; Wöhler, Christian

    2013-10-01

    This paper addresses the problem of 3D surface scan refinement, which is desirable due to noise, outliers, and missing measurements being present in the 3D surfaces obtained with a laser scanner. We present a novel algorithm for the fusion of absolute laser scanner depth profiles and photometrically estimated surface normal data, which yields a noise-reduced and highly detailed depth profile with large scale shape robustness. In contrast to other approaches published in the literature, the presented algorithm (1) regards non-Lambertian surfaces, (2) simultaneously computes surface reflectance (i.e. BRDF) parameters required for 3D reconstruction, (3) models pixelwise incident light and viewing directions, and (4) accounts for interreflections. The algorithm as such relies on the minimization of a three-component error term, which penalizes intensity deviations, integrability deviations, and deviations from the known large-scale surface shape. The solution of the error minimization is obtained iteratively based on a calculus of variations. BRDF parameters are estimated by initially reducing and then iteratively refining the optical resolution, which provides the required robust data basis. The 3D reconstruction of concave surface regions affected by interreflections is improved by compensating global illumination in the image data. The algorithm is evaluated based on eight objects with varying albedos and reflectance behaviors (diffuse, specular, metallic). The qualitative evaluation shows a removal of outliers and a strong reduction of noise, while the large scale shape is preserved. Fine surface details Which are previously not contained in the surface scans, are incorporated through using image data. The algorithm is evaluated with respect to its absolute accuracy using two caliper objects of known shape, and based on synthetically generated data. The beneficial effect of interreflection compensation on the reconstruction accuracy is evaluated quantitatively in a

  1. Calibration of an intensity ratio system for 3D imaging

    NASA Astrophysics Data System (ADS)

    Tsui, H. T.; Tang, K. C.

    1989-03-01

    An intensity ratio method for 3D imaging is proposed with error analysis given for assessment and future improvements. The method is cheap and reasonably fast as it requires no mechanical scanning or laborious correspondence computation. One drawback of the intensity ratio methods which hamper their widespread use is the undesirable change of image intensity. This is usually caused by the difference in reflection from different parts of an object surface and the automatic iris or gain control of the camera. In our method, gray-level patterns used include an uniform pattern, a staircase pattern and a sawtooth pattern to make the system more robust against errors in intensity ratio. 3D information of the surface points of an object can be derived from the intensity ratios of the images by triangulation. A reference back plane is put behind the object to monitor the change in image intensity. Errors due to camera calibration, projector calibration, variations in intensity, imperfection of the slides etc. are analyzed. Early experiments of the system using a newvicon CCTV camera with back plane intensity correction gives a mean-square range error of about 0.5 percent. Extensive analysis of various errors is expected to yield methods for improving the accuracy.

  2. Depth-controlled 3D TV image coding

    NASA Astrophysics Data System (ADS)

    Chiari, Armando; Ciciani, Bruno; Romero, Milton; Rossi, Ricardo

    1998-04-01

    Conventional 3D-TV codecs processing one down-compatible (either left, or right) channel may optionally include the extraction of the disparity field associated with the stereo-pairs to support the coding of the complementary channel. A two-fold improvement over such approaches is proposed in this paper by exploiting 3D features retained in the stereo-pairs to reduce the redundancies in both channels, and according to their visual sensitiveness. Through an a-priori disparity field analysis, our coding scheme separates a region of interest from the foreground/background in the volume space reproduced in order to code them selectively based on their visual relevance. Such a region of interest is here identified as the one which is focused by the shooting device. By suitably scaling the DCT coefficient n such a way that precision is reduced for the image blocks lying on less relevant areas, our approach aims at reducing the signal energy in the background/foreground patterns, while retaining finer details on the more relevant image portions. From an implementation point of view, it is worth noticing that the system proposed keeps its surplus processing power on the encoder side only. Simulation results show such improvements as a better image quality for a given transmission bit rate, or a graceful quality degradation of the reconstructed images with decreasing data-rates.

  3. Ice shelf melt rates and 3D imaging

    NASA Astrophysics Data System (ADS)

    Lewis, Cameron Scott

    Ice shelves are sensitive indicators of climate change and play a critical role in the stability of ice sheets and oceanic currents. Basal melting of ice shelves plays an important role in both the mass balance of the ice sheet and the global climate system. Airborne- and satellite based remote sensing systems can perform thickness measurements of ice shelves. Time separated repeat flight tracks over ice shelves of interest generate data sets that can be used to derive basal melt rates using traditional glaciological techniques. Many previous melt rate studies have relied on surface elevation data gathered by airborne- and satellite based altimeters. These systems infer melt rates by assuming hydrostatic equilibrium, an assumption that may not be accurate, especially near an ice shelf's grounding line. Moderate bandwidth, VHF, ice penetrating radar has been used to measure ice shelf profiles with relatively coarse resolution. This study presents the application of an ultra wide bandwidth (UWB), UHF, ice penetrating radar to obtain finer resolution data on the ice shelves. These data reveal significant details about the basal interface, including the locations and depth of bottom crevasses and deviations from hydrostatic equilibrium. While our single channel radar provides new insight into ice shelf structure, it only images a small swatch of the shelf, which is assumed to be an average of the total shelf behavior. This study takes an additional step by investigating the application of a 3D imaging technique to a data set collected using a ground based multi channel version of the UWB radar. The intent is to show that the UWB radar could be capable of providing a wider swath 3D image of an ice shelf. The 3D images can then be used to obtain a more complete estimate of the bottom melt rates of ice shelves.

  4. Improving 3D Wavelet-Based Compression of Hyperspectral Images

    NASA Technical Reports Server (NTRS)

    Klimesh, Matthew; Kiely, Aaron; Xie, Hua; Aranki, Nazeeh

    2009-01-01

    Two methods of increasing the effectiveness of three-dimensional (3D) wavelet-based compression of hyperspectral images have been developed. (As used here, images signifies both images and digital data representing images.) The methods are oriented toward reducing or eliminating detrimental effects of a phenomenon, referred to as spectral ringing, that is described below. In 3D wavelet-based compression, an image is represented by a multiresolution wavelet decomposition consisting of several subbands obtained by applying wavelet transforms in the two spatial dimensions corresponding to the two spatial coordinate axes of the image plane, and by applying wavelet transforms in the spectral dimension. Spectral ringing is named after the more familiar spatial ringing (spurious spatial oscillations) that can be seen parallel to and near edges in ordinary images reconstructed from compressed data. These ringing phenomena are attributable to effects of quantization. In hyperspectral data, the individual spectral bands play the role of edges, causing spurious oscillations to occur in the spectral dimension. In the absence of such corrective measures as the present two methods, spectral ringing can manifest itself as systematic biases in some reconstructed spectral bands and can reduce the effectiveness of compression of spatially-low-pass subbands. One of the two methods is denoted mean subtraction. The basic idea of this method is to subtract mean values from spatial planes of spatially low-pass subbands prior to encoding, because (a) such spatial planes often have mean values that are far from zero and (b) zero-mean data are better suited for compression by methods that are effective for subbands of two-dimensional (2D) images. In this method, after the 3D wavelet decomposition is performed, mean values are computed for and subtracted from each spatial plane of each spatially-low-pass subband. The resulting data are converted to sign-magnitude form and compressed in a

  5. 3D Seismic Characterization of the Research Facility for Geological Storage of CO2: Hontomín (Burgos, Spain)

    NASA Astrophysics Data System (ADS)

    Alcalde, J.; Martí, D.; Calahorrano, A.; Marzan, I.; Ayarza, P.; Carbonell, R.; Perez-Estaun, A.

    2011-12-01

    A technological research facility dedicated to the underground geological storage of CO2 is currently being developed by the Spanish research program on Carbon Capture and Storage (CCS) in Hontomin (Burgos, North of the Iberian Peninsula) This research program is being developed by the CIUDEN Foundation. CIUDEN is an initiative of 3 Spanish state departments (Science & Innovation, Environment and Industry). An extensive multidisciplinary site characterization phase has been carried out, including a multi-seismic data acquisition experiment. Within this effort a 36 km2 academic-oriented 3D seismic reflection survey was acquired in summer 2010. The aim of data acquisition effort are to provide high resolution images of the subsurface of the storage complex, constrain a baseline model for all the disciplines involved in the project. The main acquisition characteristics of this survey included: a mixed source (Vibroseis & explosive , 74% and 26% of the source points, respectively); 5000 shot points, distributed along 22 source lines (separated 250 m), 22 lines of receivers (separated 275 m); shot and receiver spacing along the source and receiver lines was of 25 m; this resulted in a nominal CDP-fold of 36 traces, with 13 m2 bins. This 3D-data was fully processed until migration. The main features within the processing sequence include static correction calculation, frequency filtering, trace amplitude equalization, rms velocity modeling, FK-domain filtering, 3D deconvolution, dip move-out corrections, residual static calculation and pre and post stack migration. The final high-resolution 3D-volume allowed to characterize the main tectonic structure of the dome complex, the fault system of the area and the feasibility of the reservoir for the storage. The target reservoir is a saline aquifer placed at 1400, approximately, within Lower Jurassic carbonates (Lias); the main seal is formed by inter-layered marls and marly limestones from Early to Middle Jurassic (Dogger

  6. 3D imaging with a linear light source

    NASA Astrophysics Data System (ADS)

    Lunazzi, José J.; Rivera, Noemí I. R.

    2008-04-01

    In a previous system we showed how the three-dimensionality of an object can be projected and preserved on a diffractive screen, which is just a simple diffractive holographic lens. A transmission object is illuminated with an extended filament of a white light lamp and no additional element is necessary. The system forms three-dimensional (3D) images with normal depth (orthoscopic) of the shadow type. The continuous parallax, perfect sharpness and additional characteristics of the image depend on the width and extension of the luminous filament and the properties of the diffractive lens. This new imaging system is shown to inspire an interesting extension to non-perfect reflective or refractive imaging elements because the sharpness of the image depends only on the width of the source. As new light sources are being developed that may result in very thin linear white light sources, for example, light emitting diodes, it may be useful to further develop this technique. We describe an imaging process in which a rough Fresnel metallic mirror can give a sharp image of an object due to the reduced width of a long filament lamp. We will discuss how the process could be extended to Fresnel lenses or to any aberrating imaging element.

  7. Seismic Imager Space Telescope

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin; Coste, Keith; Cunningham, J.; Sievers,Michael W.; Agnes, Gregory S.; Polanco, Otto R.; Green, Joseph J.; Cameron, Bruce A.; Redding, David C.; Avouac, Jean Philippe; Ampuero, Jean Paul; Leprince, Sebastien; Michel, Remi

    2012-01-01

    A concept has been developed for a geostationary seismic imager (GSI), a space telescope in geostationary orbit above the Pacific coast of the Americas that would provide movies of many large earthquakes occurring in the area from Southern Chile to Southern Alaska. The GSI movies would cover a field of view as long as 300 km, at a spatial resolution of 3 to 15 m and a temporal resolution of 1 to 2 Hz, which is sufficient for accurate measurement of surface displacements and photometric changes induced by seismic waves. Computer processing of the movie images would exploit these dynamic changes to accurately measure the rapidly evolving surface waves and surface ruptures as they happen. These measurements would provide key information to advance the understanding of the mechanisms governing earthquake ruptures, and the propagation and arrest of damaging seismic waves. GSI operational strategy is to react to earthquakes detected by ground seismometers, slewing the satellite to point at the epicenters of earthquakes above a certain magnitude. Some of these earthquakes will be foreshocks of larger earthquakes; these will be observed, as the spacecraft would have been pointed in the right direction. This strategy was tested against the historical record for the Pacific coast of the Americas, from 1973 until the present. Based on the seismicity recorded during this time period, a GSI mission with a lifetime of 10 years could have been in position to observe at least 13 (22 on average) earthquakes of magnitude larger than 6, and at least one (2 on average) earthquake of magnitude larger than 7. A GSI would provide data unprecedented in its extent and temporal and spatial resolution. It would provide this data for some of the world's most seismically active regions, and do so better and at a lower cost than could be done with ground-based instrumentation. A GSI would revolutionize the understanding of earthquake dynamics, perhaps leading ultimately to effective warning

  8. 3D Spectral Element Method Simulations Of The Seismic Response of Caracas (Venezuela) Basin

    NASA Astrophysics Data System (ADS)

    Delavaud, E.; Vilotte, J.; Festa, G.; Cupillard, P.

    2007-12-01

    We present here 3D numerical simulations of the response of the Caracas (Venezuela) valley up to 5 Hz for different scenarios of plane wave excitation based on the regional seismicity. Attention is focused on the effects of the 3D basin geometry and of the adjacent regional topography. The simulations are performed using Spectral Element method (SEM) together with an unstructured hexahedral mesh discretization and perfectly matched layers (PML). These simulations show 3D amplification phenomena associated with complex wave reflexion, diffraction and focalisation patterns linked to the geometry of the basin. Time and frequency analysis reveal some interesting features both in terms of amplification and energy residence in the basin. The low frequency amplification pattern is mainly controlled by the early response of the basin to the incident plane wave while the high frequency amplification patterns result mainly from late arrivals where complex 3D wave diffraction phenomena are dominating and the memory of the initial excitation is lost. Interestingly enough, it is shown that H/V method correctly predict the low frequency amplification pattern when apply to the late part of the recorded seismograms. The complex high frequency amplification pattern is shown to be associated with surface wave generation at, and propagation from, sharp edges of the basin. Importance of 3D phenomena is assessed by comparison with simple 2D simulations. Significant differences in terms of time of residence, energy and amplification levels point out the interest of complete 3D modeling. In conclusions some of the limitations associated with the use of unstructured hexahedral meshes will be adressed. Despite the use of unstructured meshing tool, modeling the geometry of geological basins remain a complex and time consuming task. Possible extensions using more elaborate techniques like non conforming domain decomposition will be also discussed in conclusion.

  9. Development of 3D microwave imaging reflectometry in LHD (invited).

    PubMed

    Nagayama, Y; Kuwahara, D; Yoshinaga, T; Hamada, Y; Kogi, Y; Mase, A; Tsuchiya, H; Tsuji-Iio, S; Yamaguchi, S

    2012-10-01

    Three-dimensional (3D) microwave imaging reflectometry has been developed in the large helical device to visualize fluctuating reflection surface which is caused by the density fluctuations. The plasma is illuminated by the probe wave with four frequencies, which correspond to four radial positions. The imaging optics makes the image of cut-off surface onto the 2D (7 × 7 channels) horn antenna mixer arrays. Multi-channel receivers have been also developed using micro-strip-line technology to handle many channels at reasonable cost. This system is first applied to observe the edge harmonic oscillation (EHO), which is an MHD mode with many harmonics that appears in the edge plasma. A narrow structure along field lines is observed during EHO. PMID:23126965

  10. Upscaling small heterogeneities for seismic wave propagation in 3D complex media

    NASA Astrophysics Data System (ADS)

    Cupillard, P.; Capdeville, Y.

    2012-04-01

    Seismic waves propagating in the Earth are affected by different sizes of heterogeneities. When modelling these waves (using numerical methods such as the SEM), taking into account heterogeneities that are much smaller than the minimum wavelength is a challenge because meshing small heterogeneities often requires important efforts and leads to high numerical costs. In this work, we present a technique which allows to upscale the small heterogeneities that can lie in an elastic medium. This technique yields a smooth effective medium and effective equations. We describe its implementation in the 3D case and we show relevant examples.

  11. Density-tapered spiral arrays for ultrasound 3-D imaging.

    PubMed

    Ramalli, Alessandro; Boni, Enrico; Savoia, Alessandro Stuart; Tortoli, Piero

    2015-08-01

    The current high interest in 3-D ultrasound imaging is pushing the development of 2-D probes with a challenging number of active elements. The most popular approach to limit this number is the sparse array technique, which designs the array layout by means of complex optimization algorithms. These algorithms are typically constrained by a few steering conditions, and, as such, cannot guarantee uniform side-lobe performance at all angles. The performance may be improved by the ungridded extensions of the sparse array technique, but this result is achieved at the expense of a further complication of the optimization process. In this paper, a method to design the layout of large circular arrays with a limited number of elements according to Fermat's spiral seeds and spatial density modulation is proposed and shown to be suitable for application to 3-D ultrasound imaging. This deterministic, aperiodic, and balanced positioning procedure attempts to guarantee uniform performance over a wide range of steering angles. The capabilities of the method are demonstrated by simulating and comparing the performance of spiral and dense arrays. A good trade-off for small vessel imaging is found, e.g., in the 60λ spiral array with 1.0λ elements and Blackman density tapering window. Here, the grating lobe level is -16 dB, the lateral resolution is lower than 6λ the depth of field is 120λ and, the average contrast is 10.3 dB, while the sensitivity remains in a 5 dB range for a wide selection of steering angles. The simulation results may represent a reference guide to the design of spiral sparse array probes for different application fields. PMID:26285181

  12. 3D-LZ helicopter ladar imaging system

    NASA Astrophysics Data System (ADS)

    Savage, James; Harrington, Walter; McKinley, R. Andrew; Burns, H. N.; Braddom, Steven; Szoboszlay, Zoltan

    2010-04-01

    A joint-service team led by the Air Force Research Laboratory's Munitions and Sensors Directorates completed a successful flight test demonstration of the 3D-LZ Helicopter LADAR Imaging System. This was a milestone demonstration in the development of technology solutions for a problem known as "helicopter brownout", the loss of situational awareness caused by swirling sand during approach and landing. The 3D-LZ LADAR was developed by H.N. Burns Engineering and integrated with the US Army Aeroflightdynamics Directorate's Brown-Out Symbology System aircraft state symbology aboard a US Army EH-60 Black Hawk helicopter. The combination of these systems provided an integrated degraded visual environment landing solution with landing zone situational awareness as well as aircraft guidance and obstacle avoidance information. Pilots from the U.S. Army, Air Force, Navy, and Marine Corps achieved a 77% landing rate in full brownout conditions at a test range at Yuma Proving Ground, Arizona. This paper will focus on the LADAR technology used in 3D-LZ and the results of this milestone demonstration.

  13. Ultra-realistic 3-D imaging based on colour holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, H. I.

    2013-02-01

    A review of recent progress in colour holography is provided with new applications. Colour holography recording techniques in silver-halide emulsions are discussed. Both analogue, mainly Denisyuk colour holograms, and digitally-printed colour holograms are described and their recent improvements. An alternative to silver-halide materials are the panchromatic photopolymer materials such as the DuPont and Bayer photopolymers which are covered. The light sources used to illuminate the recorded holograms are very important to obtain ultra-realistic 3-D images. In particular the new light sources based on RGB LEDs are described. They show improved image quality over today's commonly used halogen lights. Recent work in colour holography by holographers and companies in different countries around the world are included. To record and display ultra-realistic 3-D images with perfect colour rendering are highly dependent on the correct recording technique using the optimal recording laser wavelengths, the availability of improved panchromatic recording materials and combined with new display light sources.

  14. 3D imaging reconstruction and impacted third molars: case reports

    PubMed Central

    Tuzi, Andrea; Di Bari, Roberto; Cicconetti, Andrea

    2012-01-01

    Summary There is a debate in the literature about the need for Computed Tomagraphy (CT) before removing third molars, even if positive radiographic signs are present. In few cases, the third molar is so close to the inferior alveolar nerve that its extraction might expose patients to the risk of post-operative neuro-sensitive alterations of the skin and the mucosa of the homolateral lower lip and chin. Thus, the injury of the inferior alveolar nerve may represent a serious, though infrequent, neurologic complication in the surgery of the third molars rendering necessary a careful pre-operative evaluation of their anatomical relationship with the inferior alveolar nerve by means of radiographic imaging techniques. This contribution presents two case reports showing positive radiographic signs, which are the hallmarks of a possible close relationship between the inferior alveolar nerve and the third molars. We aim at better defining the relationship between third molars and the mandibular canal using Dental CT Scan, DICOM image acquisition and 3D reconstruction with a dedicated software. By our study we deduce that 3D images are not indispensable, but they can provide a very agreeable assistance in the most complicated cases. PMID:23386934

  15. 3D seismic attribute-assisted analysis of microseismic events in the Marcellus Shale

    NASA Astrophysics Data System (ADS)

    Hart, Ariel Kelton

    Microseismic monitoring is often used during the process of oil and gas exploitation to monitor seismicity that may be triggered by hydraulic fracturing, a common practice in the Appalachian Basin. Anthropogenically-induced minor upward fracture growth is not uncommon in the Marcellus shale; however, in the area of study, significant microseismic activity was registered above the target zone. In order to ascertain whether out-of-zone growth might have been predictable and identify which areas are more likely to experience brittle failure first, 3D seismic and microseismic data were analyzed with a focus on better understanding variations in the acoustic properties associated with unconventional naturally fractured reservoirs. Ant Tracking was used to identify areas of increased local seismic discontinuity, as these areas are generally more intensely deformed and may represent zones of increased fracture intensity. Ant Tracking results reveal discontinuities in the Marcellus are oriented approximately at N52E and N41W; discontinuities do not coincide with N25E trending folds apparent in the 3D seismic, but tend to follow deeper structural trends instead. These discontinuity orientations are interpreted to be a result of continued movement on deeper faults throughout the Paleozoic; these faults possibly acted as seed points for fractures further upsection and potentially led to the precipitation of the large N25E trending imbricate backthrusts seen in the 3D seismic. The reservoir's response to hydraulic fracturing also provided insights into local stress anisotropy and into optimal well and stage spacing needed to maximize drainage area and locate additional wells during the field development phase. Microseismic, well, and pump data used to gauge the reservoir's response to a hydraulic fracture treatment indicated that the number of stages, lateral length, total proppant volume, and fracture energy heavily influence how a well produces. SHmax in the area is oriented

  16. Applications of detailed 3D P-wave velocity crustal model in Poland for local, regional and global seismic tomography

    NASA Astrophysics Data System (ADS)

    Polkowski, Marcin; Grad, Marek

    2015-04-01

    The 3D P-wave seismic velocity model was obtained by combining data from multiple studies during past 50 years. Data sources included refraction seismology, reflection seismology, geological boreholes, vertical seismic profiling, magnetotellurics and gravimetry. Use of many data sources allowed creation of detailed 3D P-wave velocity model that reaches to depth of 60 km and includes 6-layers of sediments and 3-layers of the crust. Purpose of this study is to analyze how 3D model influences local (accuracy of location and source time estimation for local events), regional (identification of wide-angle seismic phases) and global (teleseismic tomography) seismic travel times. Additionally we compare results of forward seismic wave propagation with signals observed on short period and broadband stations. National Science Centre Poland provided financial support for this work by NCN grant DEC-2011/02/A/ST10/00284.

  17. 3D imaging of neutron tracks using confocal microscopy

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin; Wertheim, David; Flowers, Alan

    2016-04-01

    Neutron detection and neutron flux assessment are important aspects in monitoring nuclear energy production. Neutron flux measurements can also provide information on potential biological damage from exposure. In addition to the applications for neutron measurement in nuclear energy, neutron detection has been proposed as a method of enhancing neutrino detectors and cosmic ray flux has also been assessed using ground-level neutron detectors. Solid State Nuclear Track Detectors (or SSNTDs) have been used extensively to examine cosmic rays, long-lived radioactive elements, radon concentrations in buildings and the age of geological samples. Passive SSNTDs consisting of a CR-39 plastic are commonly used to measure radon because they respond to incident charged particles such as alpha particles from radon gas in air. They have a large dynamic range and a linear flux response. We have previously applied confocal microscopy to obtain 3D images of alpha particle tracks in SSNTDs from radon track monitoring (1). As a charged particle traverses through the polymer it creates an ionisation trail along its path. The trail or track is normally enhanced by chemical etching to better expose radiation damage, as the damaged area is more sensitive to the etchant than the bulk material. Particle tracks in CR-39 are usually assessed using 2D optical microscopy. In this study 6 detectors were examined using an Olympus OLS4100 LEXT 3D laser scanning confocal microscope (Olympus Corporation, Japan). The detectors had been etched for 2 hours 50 minutes at 85 °C in 6.25M NaOH. Post etch the plastics had been treated with a 10 minute immersion in a 2% acetic acid stop bath, followed by rinsing in deionised water. The detectors examined had been irradiated with a 2mSv neutron dose from an Am(Be) neutron source (producing roughly 20 tracks per mm2). We were able to successfully acquire 3D images of neutron tracks in the detectors studied. The range of track diameter observed was between 4

  18. 3D Multispectral Light Propagation Model For Subcutaneous Veins Imaging

    SciTech Connect

    Paquit, Vincent C; Price, Jeffery R; Meriaudeau, Fabrice; Tobin Jr, Kenneth William

    2008-01-01

    In this paper, we describe a new 3D light propagation model aimed at understanding the effects of various physiological properties on subcutaneous vein imaging. In particular, we build upon the well known MCML (Monte Carlo Multi Layer) code and present a tissue model that improves upon the current state-of-the-art by: incorporating physiological variation, such as melanin concentration, fat content, and layer thickness; including veins of varying depth and diameter; using curved surfaces from real arm shapes; and modeling the vessel wall interface. We describe our model, present results from the Monte Carlo modeling, and compare these results with those obtained with other Monte Carlo methods.

  19. Seismic imaging on massively parallel computers

    SciTech Connect

    Ober, C.C.; Oldfield, R.; Womble, D.E.; VanDyke, J.; Dosanjh, S.

    1996-03-01

    Fast, accurate imaging of complex, oil-bearing geologies, such as overthrusts and salt domes, is the key to reducing the costs of domestic oil and gas exploration. Geophysicists say that the known oil reserves in the Gulf of Mexico could be significantly increased if accurate seismic imaging beneath salt domes was possible. A range of techniques exist for imaging these regions, but the highly accurate techniques involve the solution of the wave equation and are characterized by large data sets and large computational demands. Massively parallel computers can provide the computational power for these highly accurate imaging techniques. A brief introduction to seismic processing will be presented, and the implementation of a seismic-imaging code for distributed memory computers will be discussed. The portable code, Salvo, performs a wave equation-based, 3-D, prestack, depth imaging and currently runs on the Intel Paragon and the Cray T3D. It used MPI for portability, and has sustained 22 Mflops/sec/proc (compiled FORTRAN) on the Intel Paragon.

  20. Quantitative 3D Optical Imaging: Applications in Dosimetry and Biophysics

    NASA Astrophysics Data System (ADS)

    Thomas, Andrew Stephen

    Optical-CT has been shown to be a potentially useful imaging tool for the two very different spheres of biologists and radiation therapy physicists, but it has yet to live up to that potential. In radiation therapy, researchers have used optical-CT for the readout of 3D dosimeters, but it is yet to be a clinically relevant tool as the technology is too slow to be considered practical. Biologists have used the technique for structural imaging, but have struggled with emission tomography as the reality of photon attenuation for both excitation and emission have made the images quantitatively irrelevant. Dosimetry. The DLOS (Duke Large field of view Optical-CT Scanner) was designed and constructed to make 3D dosimetry utilizing optical-CT a fast and practical tool while maintaining the accuracy of readout of the previous, slower readout technologies. Upon construction/optimization/implementation of several components including a diffuser, band pass filter, registration mount & fluid filtration system the dosimetry system provides high quality data comparable to or exceeding that of commercial products. In addition, a stray light correction algorithm was tested and implemented. The DLOS in combination with the 3D dosimeter it was designed for, PREAGETM, then underwent rigorous commissioning and benchmarking tests validating its performance against gold standard data including a set of 6 irradiations. DLOS commissioning tests resulted in sub-mm isotropic spatial resolution (MTF >0.5 for frequencies of 1.5lp/mm) and a dynamic range of ˜60dB. Flood field uniformity was 10% and stable after 45minutes. Stray light proved to be small, due to telecentricity, but even the residual can be removed through deconvolution. Benchmarking tests showed the mean 3D passing gamma rate (3%, 3mm, 5% dose threshold) over the 6 benchmark data sets was 97.3% +/- 0.6% (range 96%-98%) scans totaling ˜10 minutes, indicating excellent ability to perform 3D dosimetry while improving the speed of

  1. High-resolution 3D seismic model of the crustal and uppermost mantle structure in Poland

    NASA Astrophysics Data System (ADS)

    Grad, Marek; Polkowski, Marcin; Ostaficzuk, Stanisław R.

    2016-01-01

    In the area of Poland a contact between the Precambrian and Phanerozoic Europe and the Carpathians has a complicated structure and a complex P-wave velocity of the sedimentary cover, crystalline crust, Moho depth and the uppermost mantle. The geometry of the uppermost several kilometers of sediments is relatively well recognized from over 100,000 boreholes. The vertical seismic profiling (VSP) from 1188 boreholes provided detailed velocity data for regional tectonic units and for stratigraphic successions from Permian to the Tertiary and Quaternary deposits. These data, however, do not provide information about the velocity and basement depth in the central part of the Trans-European suture zone (TESZ) and in the Carpathians. So, the data set is supplemented by 2D velocity models from 32 deep seismic sounding refraction profiles which also provide information about the crust and uppermost mantle. Together with the results of other methods: vertical seismic profiling, magnetotelluric, allow for the creation of a detailed, high-resolution 3D model for the entire Earth's crust and the uppermost mantle down to a depth of 60 km. The thinnest sedimentary cover in the Mazury-Belarus anteclise is only 0.3 to 1 km thick, which increases to 7 to 8 km along the East European Craton (EEC) margin, and 9 to 12 km in the TESZ. The Variscan domain is characterized by a 1-4 km thick sedimentary cover, while the Carpathians are characterized by very thick sedimentary layers, up to about 20 km. The crystalline crust is differentiated and has a layered structure. The crust beneath the West European Platform (WEP; Variscan domain) is characterized by P-wave velocities of 5.8-6.6 km/s. The upper and middle crusts beneath the EEC are characterized by velocities of 6.1-6.6 km/s, and are underlain by a high velocity lower crust with a velocity of about 7 km/s. A general decrease in velocity is observed from the older to the younger tectonic domains. The TESZ is associated with a steep dip

  2. 3D photoacoustic imaging of a moving target

    NASA Astrophysics Data System (ADS)

    Ephrat, Pinhas; Roumeliotis, Michael; Prato, Frank S.; Carson, Jeffrey J. L.

    2009-02-01

    We have developed a fast 3D photoacoustic imaging system based on a sparse array of ultrasound detectors and iterative image reconstruction. To investigate the high frame rate capabilities of our system in the context of rotational motion, flow, and spectroscopy, we performed high frame-rate imaging on a series of targets, including a rotating graphite rod, a bolus of methylene blue flowing through a tube, and hyper-spectral imaging of a tube filled with methylene blue under a no flow condition. Our frame-rate for image acquisition was 10 Hz, which was limited by the laser repetition rate. We were able to track the rotation of the rod and accurately estimate its rotational velocity, at a rate of 0.33 rotations-per-second. The flow of contrast in the tube, at a flow rate of 180 μL/min, was also well depicted, and quantitative analysis suggested a potential method for estimating flow velocity from such measurements. The spectrum obtained did not provide accurate results, but depicted the spectral absorption signature of methylene blue , which may be sufficient for identification purposes. These preliminary results suggest that our high frame-rate photoacoustic imaging system could be used for identifying contrast agents and monitoring kinetics as an agent propagates through specific, simple structures such as blood vessels.

  3. 3-D Imaging and Simulation for Nephron Sparing Surgical Training.

    PubMed

    Ahmadi, Hamed; Liu, Jen-Jane

    2016-08-01

    Minimally invasive partial nephrectomy (MIPN) is now considered the procedure of choice for small renal masses largely based on functional advantages over traditional open surgery. Lack of haptic feedback, the need for spatial understanding of tumor borders, and advanced operative techniques to minimize ischemia time or achieve zero-ischemia PN are among factors that make MIPN a technically demanding operation with a steep learning curve for inexperienced surgeons. Surgical simulation has emerged as a useful training adjunct in residency programs to facilitate the acquisition of these complex operative skills in the setting of restricted work hours and limited operating room time and autonomy. However, the majority of available surgical simulators focus on basic surgical skills, and procedure-specific simulation is needed for optimal surgical training. Advances in 3-dimensional (3-D) imaging have also enhanced the surgeon's ability to localize tumors intraoperatively. This article focuses on recent procedure-specific simulation models for laparoscopic and robotic-assisted PN and advanced 3-D imaging techniques as part of pre- and some cases, intraoperative surgical planning. PMID:27314271

  4. 3D Reconstruction of virtual colon structures from colonoscopy images.

    PubMed

    Hong, DongHo; Tavanapong, Wallapak; Wong, Johnny; Oh, JungHwan; de Groen, Piet C

    2014-01-01

    This paper presents the first fully automated reconstruction technique of 3D virtual colon segments from individual colonoscopy images. It is the basis of new software applications that may offer great benefits for improving quality of care for colonoscopy patients. For example, a 3D map of the areas inspected and uninspected during colonoscopy can be shown on request of the endoscopist during the procedure. The endoscopist may revisit the suggested uninspected areas to reduce the chance of missing polyps that reside in these areas. The percentage of the colon surface seen by the endoscopist can be used as a coarse objective indicator of the quality of the procedure. The derived virtual colon models can be stored for post-procedure training of new endoscopists to teach navigation techniques that result in a higher level of procedure quality. Our technique does not require a prior CT scan of the colon or any global positioning device. Our experiments on endoscopy images of an Olympus synthetic colon model reveal encouraging results with small average reconstruction errors (4.1 mm for the fold depths and 12.1 mm for the fold circumferences). PMID:24225230

  5. Recent progress in 3-D imaging of sea freight containers

    NASA Astrophysics Data System (ADS)

    Fuchs, Theobald; Schön, Tobias; Dittmann, Jonas; Sukowski, Frank; Hanke, Randolf

    2015-03-01

    The inspection of very large objects like sea freight containers with X-ray Computed Tomography (CT) is an emerging technology. A complete 3-D CT scan of a see-freight container takes several hours. Of course, this is too slow to apply it to a large number of containers. However, the benefits of a 3-D CT for sealed freight are obvious: detection of potential threats or illicit cargo without being confronted with legal complications or high time consumption and risks for the security personnel during a manual inspection. Recently distinct progress was made in the field of reconstruction of projections with only a relatively low number of angular positions. Instead of today's 500 to 1000 rotational steps, as needed for conventional CT reconstruction techniques, this new class of algorithms provides the potential to reduce the number of projection angles approximately by a factor of 10. The main drawback of these advanced iterative methods is the high consumption for numerical processing. But as computational power is getting steadily cheaper, there will be practical applications of these complex algorithms in a foreseeable future. In this paper, we discuss the properties of iterative image reconstruction algorithms and show results of their application to CT of extremely large objects scanning a sea-freight container. A specific test specimen is used to quantitatively evaluate the image quality in terms of spatial and contrast resolution and depending on different number of projections.

  6. Recent progress in 3-D imaging of sea freight containers

    SciTech Connect

    Fuchs, Theobald Schön, Tobias Sukowski, Frank; Dittmann, Jonas; Hanke, Randolf

    2015-03-31

    The inspection of very large objects like sea freight containers with X-ray Computed Tomography (CT) is an emerging technology. A complete 3-D CT scan of a see-freight container takes several hours. Of course, this is too slow to apply it to a large number of containers. However, the benefits of a 3-D CT for sealed freight are obvious: detection of potential threats or illicit cargo without being confronted with legal complications or high time consumption and risks for the security personnel during a manual inspection. Recently distinct progress was made in the field of reconstruction of projections with only a relatively low number of angular positions. Instead of today’s 500 to 1000 rotational steps, as needed for conventional CT reconstruction techniques, this new class of algorithms provides the potential to reduce the number of projection angles approximately by a factor of 10. The main drawback of these advanced iterative methods is the high consumption for numerical processing. But as computational power is getting steadily cheaper, there will be practical applications of these complex algorithms in a foreseeable future. In this paper, we discuss the properties of iterative image reconstruction algorithms and show results of their application to CT of extremely large objects scanning a sea-freight container. A specific test specimen is used to quantitatively evaluate the image quality in terms of spatial and contrast resolution and depending on different number of projections.

  7. Computing 3D head orientation from a monocular image sequence

    NASA Astrophysics Data System (ADS)

    Horprasert, Thanarat; Yacoob, Yaser; Davis, Larry S.

    1997-02-01

    An approach for estimating 3D head orientation in a monocular image sequence is proposed. The approach employs recently developed image-based parameterized tracking for face and face features to locate the area in which a sub- pixel parameterized shape estimation of the eye's boundary is performed. This involves tracking of five points (four at the eye corners and the fifth is the tip of the nose). We describe an approach that relies on the coarse structure of the face to compute orientation relative to the camera plane. Our approach employs projective invariance of the cross-ratios of the eye corners and anthropometric statistics to estimate the head yaw, roll and pitch. Analytical and experimental results are reported.

  8. 3D electrical tomographic imaging using vertical arrays of electrodes

    NASA Astrophysics Data System (ADS)

    Murphy, S. C.; Stanley, S. J.; Rhodes, D.; York, T. A.

    2006-11-01

    Linear arrays of electrodes in conjunction with electrical impedance tomography have been used to spatially interrogate industrial processes that have only limited access for sensor placement. This paper explores the compromises that are to be expected when using a small number of vertically positioned linear arrays to facilitate 3D imaging using electrical tomography. A configuration with three arrays is found to give reasonable results when compared with a 'conventional' arrangement of circumferential electrodes. A single array yields highly localized sensitivity that struggles to image the whole space. Strategies have been tested on a small-scale version of a sludge settling application that is of relevance to the industrial sponsor. A new electrode excitation strategy, referred to here as 'planar cross drive', is found to give superior results to an extended version of the adjacent electrodes technique due to the improved uniformity of the sensitivity across the domain. Recommendations are suggested for parameters to inform the scale-up to industrial vessels.

  9. 3-D seismic improves structural mapping of a gas storage reservoir (Paris basin)

    SciTech Connect

    Huguet, F. ); Pinson, C. )

    1993-09-01

    In the Paris basin, anticlinal structures with closure of no more than 80 m and surface area of a few km[sup 2] are used for underground gas storage. At Soings-en-Sologne, a three-dimensional (3-D) survey (13 km[sup 2]) was carried out over such a structure to establish its exact geometry and to detail its fault network. Various reflectors were picked automatically on the migrated data: the top of the Kimmeridgian, the top of the Bathoinian and the base of the Hettangian close to the top of the reservoir. The isochron maps were converted into depth using data from 12 wells. Horizon attributes (amplitude, dip, and azimuth) were used to reconstruct the fault's pattern with much greater accuracy than that supplied by interpretation from previous two-dimensional seismic. The Triassic and the Jurassic are affected by two systems of conjugate faults (N10-N110, inherited from the Hercynian basement and N30-N120). Alternating clay and limestone are the cause of numerous structural disharmonies, particularly on both sides of the Bathonian. Ridges associated with N30-N120 faults suggest compressive movements contemporaneous with the tertiary events. The northern structure in Soings-en-Sologne thus appear to be the result of polyphased tectonics. Its closure (25 m), which is associated either with dips or faults, is described in detail by 3-D seismic, permitting more accurate forecast of the volume available for gas storage.

  10. Effect of damping and yielding on the seismic response of 3D steel buildings with PMRF.

    PubMed

    Reyes-Salazar, Alfredo; Haldar, Achintya; Rodelo-López, Ramon Eduardo; Bojórquez, Eden

    2014-01-01

    The effect of viscous damping and yielding, on the reduction of the seismic responses of steel buildings modeled as three-dimensional (3D) complex multidegree of freedom (MDOF) systems, is studied. The reduction produced by damping may be larger or smaller than that of yielding. This reduction can significantly vary from one structural idealization to another and is smaller for global than for local response parameters, which in turn depends on the particular local response parameter. The uncertainty in the estimation is significantly larger for local response parameter and decreases as damping increases. The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion. It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation. Moreover, the effect of yielding should be explicitly calculated by using complex 3D MDOF models instead of estimating it in terms of equivalent viscous damping. The findings of this paper are for the particular models used in the study. Much more research is needed to reach more general conclusions. PMID:25097892

  11. Effect of Damping and Yielding on the Seismic Response of 3D Steel Buildings with PMRF

    PubMed Central

    Haldar, Achintya; Rodelo-López, Ramon Eduardo; Bojórquez, Eden

    2014-01-01

    The effect of viscous damping and yielding, on the reduction of the seismic responses of steel buildings modeled as three-dimensional (3D) complex multidegree of freedom (MDOF) systems, is studied. The reduction produced by damping may be larger or smaller than that of yielding. This reduction can significantly vary from one structural idealization to another and is smaller for global than for local response parameters, which in turn depends on the particular local response parameter. The uncertainty in the estimation is significantly larger for local response parameter and decreases as damping increases. The results show the limitations of the commonly used static equivalent lateral force procedure where local and global response parameters are reduced in the same proportion. It is concluded that estimating the effect of damping and yielding on the seismic response of steel buildings by using simplified models may be a very crude approximation. Moreover, the effect of yielding should be explicitly calculated by using complex 3D MDOF models instead of estimating it in terms of equivalent viscous damping. The findings of this paper are for the particular models used in the study. Much more research is needed to reach more general conclusions. PMID:25097892

  12. Mono- and multistatic polarimetric sparse aperture 3D SAR imaging

    NASA Astrophysics Data System (ADS)

    DeGraaf, Stuart; Twigg, Charles; Phillips, Louis

    2008-04-01

    SAR imaging at low center frequencies (UHF and L-band) offers advantages over imaging at more conventional (X-band) frequencies, including foliage penetration for target detection and scene segmentation based on polarimetric coherency. However, bandwidths typically available at these center frequencies are small, affording poor resolution. By exploiting extreme spatial diversity (partial hemispheric k-space coverage) and nonlinear bandwidth extrapolation/interpolation methods such as Least-Squares SuperResolution (LSSR) and Least-Squares CLEAN (LSCLEAN), one can achieve resolutions that are commensurate with the carrier frequency (λ/4) rather than the bandwidth (c/2B). Furthermore, extreme angle diversity affords complete coverage of a target's backscatter, and a correspondingly more literal image. To realize these benefits, however, one must image the scene in 3-D; otherwise layover-induced misregistration compromises the coherent summation that yields improved resolution. Practically, one is limited to very sparse elevation apertures, i.e. a small number of circular passes. Here we demonstrate that both LSSR and LSCLEAN can reduce considerably the sidelobe and alias artifacts caused by these sparse elevation apertures. Further, we illustrate how a hypothetical multi-static geometry consisting of six vertical real-aperture receive apertures, combined with a single circular transmit aperture provide effective, though sparse and unusual, 3-D k-space support. Forward scattering captured by this geometry reveals horizontal scattering surfaces that are missed in monostatic backscattering geometries. This paper illustrates results based on LucernHammer UHF and L-band mono- and multi-static simulations of a backhoe.

  13. Active and interactive floating image display using holographic 3D images

    NASA Astrophysics Data System (ADS)

    Morii, Tsutomu; Sakamoto, Kunio

    2006-08-01

    We developed a prototype tabletop holographic display system. This system consists of the object recognition system and the spatial imaging system. In this paper, we describe the recognition system using an RFID tag and the 3D display system using a holographic technology. A 3D display system is useful technology for virtual reality, mixed reality and augmented reality. We have researched spatial imaging and interaction system. We have ever proposed 3D displays using the slit as a parallax barrier, the lenticular screen and the holographic optical elements(HOEs) for displaying active image 1,2,3. The purpose of this paper is to propose the interactive system using these 3D imaging technologies. In this paper, the authors describe the interactive tabletop 3D display system. The observer can view virtual images when the user puts the special object on the display table. The key technologies of this system are the object recognition system and the spatial imaging display.

  14. High Resolution 3D Radar Imaging of Comet Interiors

    NASA Astrophysics Data System (ADS)

    Asphaug, E. I.; Gim, Y.; Belton, M.; Brophy, J.; Weissman, P. R.; Heggy, E.

    2012-12-01

    Knowing the interiors of comets and other primitive bodies is fundamental to our understanding of how planets formed. We have developed a Discovery-class mission formulation, Comet Radar Explorer (CORE), based on the use of previously flown planetary radar sounding techniques, with the goal of obtaining high resolution 3D images of the interior of a small primitive body. We focus on the Jupiter-Family Comets (JFCs) as these are among the most primitive bodies reachable by spacecraft. Scattered in from far beyond Neptune, they are ultimate targets of a cryogenic sample return mission according to the Decadal Survey. Other suitable targets include primitive NEOs, Main Belt Comets, and Jupiter Trojans. The approach is optimal for small icy bodies ~3-20 km diameter with spin periods faster than about 12 hours, since (a) navigation is relatively easy, (b) radar penetration is global for decameter wavelengths, and (c) repeated overlapping ground tracks are obtained. The science mission can be as short as ~1 month for a fast-rotating JFC. Bodies smaller than ~1 km can be globally imaged, but the navigation solutions are less accurate and the relative resolution is coarse. Larger comets are more interesting, but radar signal is unlikely to be reflected from depths greater than ~10 km. So, JFCs are excellent targets for a variety of reasons. We furthermore focus on the use of Solar Electric Propulsion (SEP) to rendezvous shortly after the comet's perihelion. This approach leaves us with ample power for science operations under dormant conditions beyond ~2-3 AU. This leads to a natural mission approach of distant observation, followed by closer inspection, terminated by a dedicated radar mapping orbit. Radar reflections are obtained from a polar orbit about the icy nucleus, which spins underneath. Echoes are obtained from a sounder operating at dual frequencies 5 and 15 MHz, with 1 and 10 MHz bandwidths respectively. The dense network of echoes is used to obtain global 3D

  15. Object Segmentation and Ground Truth in 3D Embryonic Imaging

    PubMed Central

    Rajasekaran, Bhavna; Uriu, Koichiro; Valentin, Guillaume; Tinevez, Jean-Yves; Oates, Andrew C.

    2016-01-01

    Many questions in developmental biology depend on measuring the position and movement of individual cells within developing embryos. Yet, tools that provide this data are often challenged by high cell density and their accuracy is difficult to measure. Here, we present a three-step procedure to address this problem. Step one is a novel segmentation algorithm based on image derivatives that, in combination with selective post-processing, reliably and automatically segments cell nuclei from images of densely packed tissue. Step two is a quantitative validation using synthetic images to ascertain the efficiency of the algorithm with respect to signal-to-noise ratio and object density. Finally, we propose an original method to generate reliable and experimentally faithful ground truth datasets: Sparse-dense dual-labeled embryo chimeras are used to unambiguously measure segmentation errors within experimental data. Together, the three steps outlined here establish a robust, iterative procedure to fine-tune image analysis algorithms and microscopy settings associated with embryonic 3D image data sets. PMID:27332860

  16. Q AS A LITHOLOGICAL/HYDROCARBON INDICATOR: FROM FULL WAVEFORM SONIC TO 3D SURFACE SEISMIC

    SciTech Connect

    Jorge O. Parra; C.L. Hackert; L. Wilson; H.A. Collier; J. Todd Thomas

    2006-03-31

    The goal of this project was to develop a method to exploit viscoelastic rock and fluid properties to greatly enhance the sensitivity of surface seismic measurements to the presence of hydrocarbon saturation. To reach the objective, Southwest Research Institute scientists used well log, lithology, production, and 3D seismic data from an oil reservoir located on the Waggoner Ranch in north central Texas. The project was organized in three phases. In the first phase, we applied modeling techniques to investigate seismic- and acoustic-frequency wave attenuation and its effect on observable wave attributes. We also gathered existing data and acquired new data from the Waggoner Ranch field, so that all needed information was in place for the second phase. During the second phase, we developed methods to extract attenuation from borehole acoustic and surface seismic data. These methods were tested on synthetic data constructed from realistic models and real data. In the third and final phase of the project, we applied this technology to a full data set from the Waggoner site. The results presented in this Final Report show that geological conditions at the site did not allow us to obtain interpretable results from the Q processing algorithm for 3D seismic data. However, the Q-log processing algorithm was successfully applied to full waveform sonic data from the Waggoner site. A significant part of this project was technology transfer. We have published several papers and conducted presentations at professional conferences. In particular, we presented the Q-log algorithm and applications at the Society of Exploration Geophysicists (SEG) Development and Production Forum in Austin, Texas, in May 2005. The presentation attracted significant interest from the attendees and, at the request of the SEG delegates, it was placed on the Southwest Research Institute Internet site. The presentation can be obtained from the following link: http://www.swri.org/4org/d15/elecsys

  17. 3D absolute hypocentral determination - 13 years of seismicity in Ecuadorian subduction zone

    NASA Astrophysics Data System (ADS)

    Font, Yvonne; Segovia, Monica; Theunissen, Thomas

    2010-05-01

    In Ecuador, the Nazca plate is subducting beneath the North Andean Block. This subduction triggered, during the last century, 4 major earthquakes of magnitude greater than 7.7. Between 1994 and 2007, the Geophysical Institute (Escuela National Politecnica, Quito) recorded about 40 000 events in whole Ecuador ranging from Mb 1.5 to 6.9. Unfortunately, the local network shows great density discrepancy between the Coastal and Andean regions where numerous stations were installed to survey volcanic activity. Consequently, seismicity in and around the interplate seismogenic zone - producer of the most destructive earthquakes and tsunamis - is not well constrained. This study aims to improve the location of 13 years seismicity occurred during an interseismic period in order to better localize the seismic deformation and gaps. The first step consists in the construction of a 3D "georealistic" velocity model. Because local tomography cannot provide satisfactory model, we combined all local crustal/lithospheric information on the geometry and velocity properties of different geological units. Those information cover the oceanic Nazca plate and sedimentary coverture the subducting plate dip angle; the North Andean Block margin composed of accreted oceanic plateaus (the Moho depth is approximated using gravity modeling); the metamorphic volcanic chain (oceanic nature for the occidental cordillera and inter-andean valley, continental one for the oriental cordillera); The continental Guyana shield and sedimentary basins. The resulting 3D velocity model extends from 2°N to 6.5°S and 277°E to 283°E and reaches a depth of 300 km. It is discretized in constant velocity blocks of 12 x 12 x 3 km in x, y and z, respectively. The second step consists in selecting an adequate sub-set of seismic stations in order to correct the effect of station density disequilibrium between coastal and volcanic regions. Consequently, we only keep the most representative volcanic stations in terms

  18. 3D gravity modeling of a salt structure associated to the Trozza-Labaied lineament (Central Tunisia) constrained by seismic and borehole data

    NASA Astrophysics Data System (ADS)

    Djebbi, M.; Gabtni, H.

    2015-03-01

    Gravity and seismic are two distinctive geophysical methods which are used combined in integrated geophysical studies. The rationale behind this integration is to construct a 3D gravity model for a salt structure associated to the Trozza-Labaied major tectonic deformation. The Trozza-Labaied area witnessed the occurrence of several tectonic events during the Atlassic phase resulting in the creation of various salt structures. Interpretation of the available seismic data revealed the different lithological units forming the geologic setting. Whereas the analysis of the gravity data contributed in exposing the existence of different gravity anomalies. Thus, the integrated seismic and gravity data are fundamental in constructing a 3D gravity model. The resulting model provides an accurate image of the salt body extent and its geometry and determines its effect over the surrounding sedimentary deposits.

  19. Microgravity Characterization of the Hontomín CO2 Storage Site (Spain). Integration with 3D Seismic Results

    NASA Astrophysics Data System (ADS)

    Ayarza, P.; Andres, J.; Alcalde, J.; Martí, D.; Marzán, I.; Martinez-Catalan, J. R.; Carbonell, R.; García Lobón, J. L.; Pérez Estaún, A.

    2014-12-01

    Hontomín hosts the first Spanish CO2storage Technology Development Plant. The area, located in the southern part of Mesozoic Basque-Cantabrian Basin, presents E-W and ESE-WNW faults formed during a Permian-Triassic extensional event. The latter were reactivated during the opening of the Bay of Biscay, while a new set of NNE-SSW faults developed. Fractures were reactivated again during the Alpine compression. The resulting configuration is a dome-like structure that includes the Mesozoic succession (Upper Triassic to Lower Cretaceous) and is crowned by Upper Cretaceous and Eocene rocks lying unconformably. The target injection pointis located at 1500 m depth, within a Jurassic carbonate saline formation. Several multidisciplinary studies have been carried out in Hontomín aiming to obtain a thorough geological characterization. Among these, a microgravity survey, acquired under the umbrella of the CIUDEN foundation, has provided us with a complete 3D image of the site. A 4x4 km2area, coincident with that surveyed by 3D seismic reflection, has been sampled using a dense grid with a station spacing of 100 m. The result is a high resolution Bouguer anomaly gravity map capable of offering insights into the subsurface geology down to the depth of the injection point. The application of mathematical procedures to the data has further enhanced its potential for interpretation. The calculated regional anomaly indicates that the dome structure strikes E-W to ENE-WSW, sub-parallel to a major fault: the South Fault, part of the Ubierna fault system. The resulting residual anomaly enhances a number of NW-SE features that have also been interpreted as faults and that can be observed after performing vertical and horizontal derivatives to the data. Calculation of the Euler solutions confirms the previous results and brings out a new NNW-SSE feature, namely the East Fault. Integration with 3D seismic data suggests that faults affect different levels of the sedimentary sequence

  20. Research of Fast 3D Imaging Based on Multiple Mode

    NASA Astrophysics Data System (ADS)

    Chen, Shibing; Yan, Huimin; Ni, Xuxiang; Zhang, Xiuda; Wang, Yu

    2016-02-01

    Three-dimensional (3D) imaging has received increasingly extensive attention and has been widely used currently. Lots of efforts have been put on three-dimensional imaging method and system study, in order to meet fast and high accurate requirement. In this article, we realize a fast and high quality stereo matching algorithm on field programmable gate array (FPGA) using the combination of time-of-flight (TOF) camera and binocular camera. Images captured from the two cameras own a same spatial resolution, letting us use the depth maps taken by the TOF camera to figure initial disparity. Under the constraint of the depth map as the stereo pairs when comes to stereo matching, expected disparity of each pixel is limited within a narrow search range. In the meanwhile, using field programmable gate array (FPGA, altera cyclone IV series) concurrent computing we can configure multi core image matching system, thus doing stereo matching on embedded system. The simulation results demonstrate that it can speed up the process of stereo matching and increase matching reliability and stability, realize embedded calculation, expand application range.

  1. Brain surface maps from 3-D medical images

    NASA Astrophysics Data System (ADS)

    Lu, Jiuhuai; Hansen, Eric W.; Gazzaniga, Michael S.

    1991-06-01

    The anatomic and functional localization of brain lesions for neurologic diagnosis and brain surgery is facilitated by labeling the cortical surface in 3D images. This paper presents a method which extracts cortical contours from magnetic resonance (MR) image series and then produces a planar surface map which preserves important anatomic features. The resultant map may be used for manual anatomic localization as well as for further automatic labeling. Outer contours are determined on MR cross-sectional images by following the clear boundaries between gray matter and cerebral-spinal fluid, skipping over sulci. Carrying this contour below the surface by shrinking it along its normal produces an inner contour that alternately intercepts gray matter (sulci) and white matter along its length. This procedure is applied to every section in the set, and the image (grayscale) values along the inner contours are radially projected and interpolated onto a semi-cylindrical surface with axis normal to the slices and large enough to cover the whole brain. A planar map of the cortical surface results by flattening this cylindrical surface. The projection from inner contour to cylindrical surface is unique in the sense that different points on the inner contour correspond to different points on the cylindrical surface. As the outer contours are readily obtained by automatic segmentation, cortical maps can be made directly from an MR series.

  2. Fast 3D subsurface imaging with stepped-frequency GPR

    NASA Astrophysics Data System (ADS)

    Masarik, Matthew P.; Burns, Joseph; Thelen, Brian T.; Sutter, Lena

    2015-05-01

    This paper investigates an algorithm for forming 3D images of the subsurface using stepped-frequency GPR data. The algorithm is specifically designed for a handheld GPR and therefore accounts for the irregular sampling pattern in the data and the spatially-variant air-ground interface by estimating an effective "ground-plane" and then registering the data to the plane. The algorithm efficiently solves the 4th-order polynomial for the Snell reflection points using a fully vectorized iterative scheme. The forward operator is implemented efficiently using an accelerated nonuniform FFT (Greengard and Lee, 2004); the adjoint operator is implemented efficiently using an interpolation step coupled with an upsampled FFT. The imaging is done as a linearized version of the full inverse problem, which is regularized using a sparsity constraint to reduce sidelobes and therefore improve image localization. Applying an appropriate sparsity constraint, the algorithm is able to eliminate most the surrounding clutter and sidelobes, while still rendering valuable image properties such as shape and size. The algorithm is applied to simulated data, controlled experimental data (made available by Dr. Waymond Scott, Georgia Institute of Technology), and government-provided data with irregular sampling and air-ground interface.

  3. Image appraisal for 2D and 3D electromagnetic inversion

    SciTech Connect

    Alumbaugh, D.L.; Newman, G.A.

    1998-04-01

    Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and model covariance matrices can be directly calculated. The columns of the model resolution matrix are shown to yield empirical estimates of the horizontal and vertical resolution throughout the imaging region. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how the estimated data noise maps into parameter error. When the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion), an iterative method can be applied to statistically estimate the model covariance matrix, as well as a regularization covariance matrix. The latter estimates the error in the inverted results caused by small variations in the regularization parameter. A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on a synthetic cross well EM data set.

  4. 3D geometric analysis of the aorta in 3D MRA follow-up pediatric image data

    NASA Astrophysics Data System (ADS)

    Wörz, Stefan; Alrajab, Abdulsattar; Arnold, Raoul; Eichhorn, Joachim; von Tengg-Kobligk, Hendrik; Schenk, Jens-Peter; Rohr, Karl

    2014-03-01

    We introduce a new model-based approach for the segmentation of the thoracic aorta and its main branches from follow-up pediatric 3D MRA image data. For robust segmentation of vessels even in difficult cases (e.g., neighboring structures), we propose a new extended parametric cylinder model which requires only relatively few model parameters. The new model is used in conjunction with a two-step fitting scheme for refining the segmentation result yielding an accurate segmentation of the vascular shape. Moreover, we include a novel adaptive background masking scheme and we describe a spatial normalization scheme to align the segmentation results from follow-up examinations. We have evaluated our proposed approach using different 3D synthetic images and we have successfully applied the approach to follow-up pediatric 3D MRA image data.

  5. Significant reserve additions from oligocene Hackberry Sands utilizing 3-D seismic, upper Texas and Louisiana Gulf Coast

    SciTech Connect

    Zamboras, R.L.

    1995-10-01

    The Oligocene Hackberry sands of the Hackberry Embayment represent a complex and elusive exploration target. 3-D seismic evaluation along the headward erosional limits of the embayment provides a reconstructive framework of tectonic and sedimentation patterns which facilitate hydrocarbon exploration. The 3-D seismic along the Orange County, Texas portion of the Oligocene Hackberry trend indicates: (1) similarities of Hackberry structural and depositional setting to that of the underlying Eocene Yegua Formation; (2) four distinct cyclical sedimentation episodes associated with basin floor slump faulting: (3) the usefulness of seismic attributes as direct hydrocarbon indicators, and (4) the potential for significant oil and gas reserves additions in a mature trend. The Hackberry embayment represents a microcosm of the basin structural and depositional processes. Utilizing 3-D seismic to lower risk and finding cost will renew interest in trends such as the Hackberry of the Upper Texas-Louisiana Gulf Coast.

  6. 3D Chemical and Elemental Imaging by STXM Spectrotomography

    SciTech Connect

    Wang, J.; Karunakaran, C.; Lu, Y.; Hormes, J.; Hitchcock, A. P.; Prange, A.; Franz, B.; Harkness, T.; Obst, M.

    2011-09-09

    Spectrotomography based on the scanning transmission x-ray microscope (STXM) at the 10ID-1 spectromicroscopy beamline of the Canadian Light Source was used to study two selected unicellular microorganisms. Spatial distributions of sulphur globules, calcium, protein, and polysaccharide in sulphur-metabolizing bacteria (Allochromatium vinosum) were determined at the S 2p, C 1s, and Ca 2p edges. 3D chemical mapping showed that the sulphur globules are located inside the bacteria with a strong spatial correlation with calcium ions (it is most probably calcium carbonate from the medium; however, with STXM the distribution and localization in the cell can be made visible, which is very interesting for a biologist) and polysaccharide-rich polymers, suggesting an influence of the organic components on the formation of the sulphur and calcium deposits. A second study investigated copper accumulating in yeast cells (Saccharomyces cerevisiae) treated with copper sulphate. 3D elemental imaging at the Cu 2p edge showed that Cu(II) is reduced to Cu(I) on the yeast cell wall. A novel needle-like wet cell sample holder for STXM spectrotomography studies of fully hydrated samples is discussed.

  7. 3D and multispectral imaging for subcutaneous veins detection.

    PubMed

    Paquit, Vincent C; Tobin, Kenneth W; Price, Jeffery R; Mèriaudeau, Fabrice

    2009-07-01

    The first and perhaps most important phase of a surgical procedure is the insertion of an intravenous (IV) catheter. Currently, this is performed manually by trained personnel. In some visions of future operating rooms, however, this process is to be replaced by an automated system. Experiments to determine the best NIR wavelengths to optimize vein contrast for physiological differences such as skin tone and/or the presence of hair on the arm or wrist surface are presented. For illumination our system is composed of a mercury arc lamp coupled to a 10nm band-pass spectrometer. A structured lighting system is also coupled to our multispectral system in order to provide 3D information of the patient arm orientation. Images of each patient arm are captured under every possible combinations of illuminants and the optimal combination of wavelengths for a given subject to maximize vein contrast using linear discriminant analysis is determined. PMID:19582050

  8. An Efficient 3D Imaging using Structured Light Systems

    NASA Astrophysics Data System (ADS)

    Lee, Deokwoo

    Structured light 3D surface imaging has been crucial in the fields of image processing and computer vision, particularly in reconstruction, recognition and others. In this dissertation, we propose the approaches to development of an efficient 3D surface imaging system using structured light patterns including reconstruction, recognition and sampling criterion. To achieve an efficient reconstruction system, we address the problem in its many dimensions. In the first, we extract geometric 3D coordinates of an object which is illuminated by a set of concentric circular patterns and reflected to a 2D image plane. The relationship between the original and the deformed shape of the light patterns due to a surface shape provides sufficient 3D coordinates information. In the second, we consider system efficiency. The efficiency, which can be quantified by the size of data, is improved by reducing the number of circular patterns to be projected onto an object of interest. Akin to the Shannon-Nyquist Sampling Theorem, we derive the minimum number of circular patterns which sufficiently represents the target object with no considerable information loss. Specific geometric information (e.g. the highest curvature) of an object is key to deriving the minimum sampling density. In the third, the object, represented using the minimum number of patterns, has incomplete color information (i.e. color information is given a priori along with the curves). An interpolation is carried out to complete the photometric reconstruction. The results can be approximately reconstructed because the minimum number of the patterns may not exactly reconstruct the original object. But the result does not show considerable information loss, and the performance of an approximate reconstruction is evaluated by performing recognition or classification. In an object recognition, we use facial curves which are deformed circular curves (patterns) on a target object. We simply carry out comparison between the

  9. 3D imaging of semiconductor components by discrete laminography

    SciTech Connect

    Batenburg, K. J.; Palenstijn, W. J.; Sijbers, J.

    2014-06-19

    X-ray laminography is a powerful technique for quality control of semiconductor components. Despite the advantages of nondestructive 3D imaging over 2D techniques based on sectioning, the acquisition time is still a major obstacle for practical use of the technique. In this paper, we consider the application of Discrete Tomography to laminography data, which can potentially reduce the scanning time while still maintaining a high reconstruction quality. By incorporating prior knowledge in the reconstruction algorithm about the materials present in the scanned object, far more accurate reconstructions can be obtained from the same measured data compared to classical reconstruction methods. We present a series of simulation experiments that illustrate the potential of the approach.

  10. 3D imaging of semiconductor components by discrete laminography

    NASA Astrophysics Data System (ADS)

    Batenburg, K. J.; Palenstijn, W. J.; Sijbers, J.

    2014-06-01

    X-ray laminography is a powerful technique for quality control of semiconductor components. Despite the advantages of nondestructive 3D imaging over 2D techniques based on sectioning, the acquisition time is still a major obstacle for practical use of the technique. In this paper, we consider the application of Discrete Tomography to laminography data, which can potentially reduce the scanning time while still maintaining a high reconstruction quality. By incorporating prior knowledge in the reconstruction algorithm about the materials present in the scanned object, far more accurate reconstructions can be obtained from the same measured data compared to classical reconstruction methods. We present a series of simulation experiments that illustrate the potential of the approach.

  11. Seismic shaking scenarios in realistic 3D crustal model of Northern Italy

    NASA Astrophysics Data System (ADS)

    Molinari, I.; Morelli, A.; Basini, P.; Berbellini, A.

    2013-12-01

    Simulation of seismic wave propagation in realistic crustal structures is a fundamental tool to evaluate earthquake-generated ground shaking and assess seismic hazard. Current-generation numerical codes, and modern HPC infrastructures, allow for realistic simulations in complex 3D geologic structures. We apply such methodology to the Po Plain in Northern Italy -- a region with relatively rare earthquakes but having large property and industrial exposure, as it became clear during the two M~6 events of May 20-29, 2012. Historical seismicity is well known in this region, with maximum magnitudes estimates reaching M~7, and wave field amplitudes may be significantly amplified by the presence of the very thick sedimentary basin. Our goal is to produce estimates of expected ground shaking in Northern Italy through detailed deterministic simulations of ground motion due to expected earthquakes. We defined a three-dimensional model of the earth's crust using geo-statistical tools to merge the abundant information existing in the form of borehole data and seismic reflection profiles that had been shot in the '70s and the '80s for hydrocarbon exploration. Such information, that has been used by geologists to infer the deep structural setup, had never been merged to build a 3D model to be used for seismological simulations. We implement the model in SPECFEM3D_Cartesian and a hexahedral mesh with elements of ~2km, that allows us to simulate waves with minimum period of ~2 seconds. The model has then been optimized through comparison between simulated and recorded seismograms for the ~20 moderate-magnitude events (Mw > 4.5) that have been instrumentally recorded in the last 15 years. Realistic simulations in the frequency band of most common engineering relevance -- say, ~1 Hz -- at such a large scale would require an extremely detailed structural model, currently not available, and prohibitive computational resources. However, an interest is growing in longer period ground

  12. Needle placement for piriformis injection using 3-D imaging.

    PubMed

    Clendenen, Steven R; Candler, Shawn A; Osborne, Michael D; Palmer, Scott C; Duench, Stephanie; Glynn, Laura; Ghazi, Salim M

    2013-01-01

    Piriformis syndrome is a pain syndrome originating in the buttock and is attributed to 6% - 8% of patients referred for the treatment of back and leg pain. The treatment for piriformis syndrome using fluoroscopy, computed tomography (CT), electromyography (EMG), and ultrasound (US) has become standard practice. The treatment of Piriformis Syndrome has evolved to include fluoroscopy and EMG with CT guidance. We present a case study of 5 successful piriformis injections using 3-D computer-assisted electromagnet needle tracking coupled with ultrasound. A 6-degree of freedom electromagnetic position tracker was attached to the ultrasound probe that allowed the system to detect the position and orientation of the probe in the magnetic field. The tracked ultrasound probe was used to find the posterior superior iliac spine. Subsequently, 3 points were captured to register the ultrasound image with the CT or magnetic resonance image scan. Moreover, after the registration was obtained, the navigation system visualized the tracked needle relative to the CT scan in real-time using 2 orthogonal multi-planar reconstructions centered at the tracked needle tip. Conversely, a recent study revealed that fluoroscopically guided injections had 30% accuracy compared to ultrasound guided injections, which tripled the accuracy percentage. This novel technique exhibited an accurate needle guidance injection precision of 98% while advancing to the piriformis muscle and avoiding the sciatic nerve. The mean (± SD) procedure time was 19.08 (± 4.9) minutes. This technique allows for electromagnetic instrument tip tracking with real-time 3-D guidance to the selected target. As with any new technique, a learning curve is expected; however, this technique could offer an alternative, minimizing radiation exposure. PMID:23703429

  13. GPU-accelerated denoising of 3D magnetic resonance images

    SciTech Connect

    Howison, Mark; Wes Bethel, E.

    2014-05-29

    The raw computational power of GPU accelerators enables fast denoising of 3D MR images using bilateral filtering, anisotropic diffusion, and non-local means. In practice, applying these filtering operations requires setting multiple parameters. This study was designed to provide better guidance to practitioners for choosing the most appropriate parameters by answering two questions: what parameters yield the best denoising results in practice? And what tuning is necessary to achieve optimal performance on a modern GPU? To answer the first question, we use two different metrics, mean squared error (MSE) and mean structural similarity (MSSIM), to compare denoising quality against a reference image. Surprisingly, the best improvement in structural similarity with the bilateral filter is achieved with a small stencil size that lies within the range of real-time execution on an NVIDIA Tesla M2050 GPU. Moreover, inappropriate choices for parameters, especially scaling parameters, can yield very poor denoising performance. To answer the second question, we perform an autotuning study to empirically determine optimal memory tiling on the GPU. The variation in these results suggests that such tuning is an essential step in achieving real-time performance. These results have important implications for the real-time application of denoising to MR images in clinical settings that require fast turn-around times.

  14. Spectral ladar: towards active 3D multispectral imaging

    NASA Astrophysics Data System (ADS)

    Powers, Michael A.; Davis, Christopher C.

    2010-04-01

    In this paper we present our Spectral LADAR concept, an augmented implementation of traditional LADAR. This sensor uses a polychromatic source to obtain range-resolved 3D spectral images which are used to identify objects based on combined spatial and spectral features, resolving positions in three dimensions and up to hundreds of meters in distance. We report on a proof-of-concept Spectral LADAR demonstrator that generates spectral point clouds from static scenes. The demonstrator transmits nanosecond supercontinuum pulses generated in a photonic crystal fiber. Currently we use a rapidly tuned receiver with a high-speed InGaAs APD for 25 spectral bands with the future expectation of implementing a linear APD array spectrograph. Each spectral band is independently range resolved with multiple return pulse recognition. This is a critical feature, enabling simultaneous spectral and spatial unmixing of partially obscured objects when not achievable using image fusion of monochromatic LADAR and passive spectral imagers. This enables higher identification confidence in highly cluttered environments such as forested or urban areas (e.g. vehicles behind camouflage or foliage). These environments present challenges for situational awareness and robotic perception which can benefit from the unique attributes of Spectral LADAR. Results from this demonstrator unit are presented for scenes typical of military operations and characterize the operation of the device. The results are discussed here in the context of autonomous vehicle navigation and target recognition.

  15. 3D segmentation of prostate ultrasound images using wavelet transform

    NASA Astrophysics Data System (ADS)

    Akbari, Hamed; Yang, Xiaofeng; Halig, Luma V.; Fei, Baowei

    2011-03-01

    The current definitive diagnosis of prostate cancer is transrectal ultrasound (TRUS) guided biopsy. However, the current procedure is limited by using 2D biopsy tools to target 3D biopsy locations. This paper presents a new method for automatic segmentation of the prostate in three-dimensional transrectal ultrasound images, by extracting texture features and by statistically matching geometrical shape of the prostate. A set of Wavelet-based support vector machines (WSVMs) are located and trained at different regions of the prostate surface. The WSVMs capture texture priors of ultrasound images for classification of the prostate and non-prostate tissues in different zones around the prostate boundary. In the segmentation procedure, these W-SVMs are trained in three sagittal, coronal, and transverse planes. The pre-trained W-SVMs are employed to tentatively label each voxel around the surface of the model as a prostate or non-prostate voxel by the texture matching. The labeled voxels in three planes after post-processing is overlaid on a prostate probability model. The probability prostate model is created using 10 segmented prostate data. Consequently, each voxel has four labels: sagittal, coronal, and transverse planes and one probability label. By defining a weight function for each labeling in each region, each voxel is labeled as a prostate or non-prostate voxel. Experimental results by using real patient data show the good performance of the proposed model in segmenting the prostate from ultrasound images.

  16. Micro-optical system based 3D imaging for full HD depth image capturing

    NASA Astrophysics Data System (ADS)

    Park, Yong-Hwa; Cho, Yong-Chul; You, Jang-Woo; Park, Chang-Young; Yoon, Heesun; Lee, Sang-Hun; Kwon, Jong-Oh; Lee, Seung-Wan

    2012-03-01

    20 Mega-Hertz-switching high speed image shutter device for 3D image capturing and its application to system prototype are presented. For 3D image capturing, the system utilizes Time-of-Flight (TOF) principle by means of 20MHz high-speed micro-optical image modulator, so called 'optical shutter'. The high speed image modulation is obtained using the electro-optic operation of the multi-layer stacked structure having diffractive mirrors and optical resonance cavity which maximizes the magnitude of optical modulation. The optical shutter device is specially designed and fabricated realizing low resistance-capacitance cell structures having small RC-time constant. The optical shutter is positioned in front of a standard high resolution CMOS image sensor and modulates the IR image reflected from the object to capture a depth image. Suggested novel optical shutter device enables capturing of a full HD depth image with depth accuracy of mm-scale, which is the largest depth image resolution among the-state-of-the-arts, which have been limited up to VGA. The 3D camera prototype realizes color/depth concurrent sensing optical architecture to capture 14Mp color and full HD depth images, simultaneously. The resulting high definition color/depth image and its capturing device have crucial impact on 3D business eco-system in IT industry especially as 3D image sensing means in the fields of 3D camera, gesture recognition, user interface, and 3D display. This paper presents MEMS-based optical shutter design, fabrication, characterization, 3D camera system prototype and image test results.

  17. High-resolution 3D seismic investigation of giant seafloor craters in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Waage, Malin; Bünz, Stefan; Andreassen, Karin

    2016-04-01

    Multiple giant craters exist on the seafloor in an area of ~ 100 km2 east of Bear Island Trough in the west-central Barents Sea. It has been hypothesized that these craters might have been caused by gas eruptions following the last deglaciation. Gas seepage from the seafloor occurs abundantly in this area. The crater area is still likely to represent one of the largest hot-spots for shallow marine methane release in the arctic. In summer 2015, we acquired high-resolution P-Cable 3D seismic data in this area covering several of the craters and their associated pingo structures. Due to the shallow and hard Triassic bedrock, penetration of the seismic signals is limited to approximately 450 ms bsf. The crater structures are up to 1 km wide and 40 m deep. Pingo structures occur on the rim of some of the craters and are up to 700 m wide and up to 15 m high above the surrounding seafloor. The 3D seismic data reveals faults, fracture networks and weakness zone that resemble pipes or similar vertical, focused fluid-flow structures in the Triassic sedimentary rocks below the craters. The principal orientation of the faults is in a ~ NW-SE direction that coincides with regional faulting from Permo-Triassic extension. The seismic data also show high-amplitude anomalies beneath some of representing shallow gas accumulations that might be the intermediate source of the gas seepage. This might suggest that craters are caused by high pressured gas that migrated from deeper petroleum systems and accumulated in the shallow Triassic rocks during the last glaciation. Previous work indicate that craters of similar size are likely a cause of enormous blow-outs of gas. Our study discusses the formation mechanisms and timing of these potential blow-out craters and whether they formed during the last deglaciation, when this area was likely quite unstable as severe glacial erosion caused localized high isostatic rebound rates here. We also investigate the role of gas hydrates that might

  18. 3-D seismic over the Fausse Pointe Field: A case history of acquisition in a harsh environment

    SciTech Connect

    Duncan, P.M.; Nester, D.C.; Martin, J.A.; Moles, J.R.

    1995-12-31

    A 50 square mile 3D seismic survey was successfully acquired over Fausse Point Field in the latter half of 1994. The geophysical and logistical challenges of this project were immense. The steep dips and extensive range of target depths required a large shoot area with a relatively fine sampling interval. The surface, while essentially flat, included areas of cane field, crawfish ponds, thick brush, swamp, open lakes and deep canals -- all typical of southern Louisiana. Planning and permitting of the survey began in late 1993. Field operations began in June 1994 and were complete in January 1995. Field personnel numbered 150 at the peak of operations. More than 19,000 crew hours were required to complete the job at a cost of over 5,000,000. The project was complete on time and on budget. The resulting images of the salt dome and surrounding rocks are not only beautiful but are revealing many opportunities for new hydrocarbon development.

  19. Performance assessment of 3D surface imaging technique for medical imaging applications

    NASA Astrophysics Data System (ADS)

    Li, Tuotuo; Geng, Jason; Li, Shidong

    2013-03-01

    Recent development in optical 3D surface imaging technologies provide better ways to digitalize the 3D surface and its motion in real-time. The non-invasive 3D surface imaging approach has great potential for many medical imaging applications, such as motion monitoring of radiotherapy, pre/post evaluation of plastic surgery and dermatology, to name a few. Various commercial 3D surface imaging systems have appeared on the market with different dimension, speed and accuracy. For clinical applications, the accuracy, reproducibility and robustness across the widely heterogeneous skin color, tone, texture, shape properties, and ambient lighting is very crucial. Till now, a systematic approach for evaluating the performance of different 3D surface imaging systems still yet exist. In this paper, we present a systematic performance assessment approach to 3D surface imaging system assessment for medical applications. We use this assessment approach to exam a new real-time surface imaging system we developed, dubbed "Neo3D Camera", for image-guided radiotherapy (IGRT). The assessments include accuracy, field of view, coverage, repeatability, speed and sensitivity to environment, texture and color.

  20. High resolution 3D imaging of synchrotron generated microbeams

    SciTech Connect

    Gagliardi, Frank M.; Cornelius, Iwan; Blencowe, Anton; Franich, Rick D.; Geso, Moshi

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  1. 3D Slicer as an Image Computing Platform for the Quantitative Imaging Network

    PubMed Central

    Fedorov, Andriy; Beichel, Reinhard; Kalpathy-Cramer, Jayashree; Finet, Julien; Fillion-Robin, Jean-Christophe; Pujol, Sonia; Bauer, Christian; Jennings, Dominique; Fennessy, Fiona; Sonka, Milan; Buatti, John; Aylward, Stephen; Miller, James V.; Pieper, Steve; Kikinis, Ron

    2012-01-01

    Quantitative analysis has tremendous but mostly unrealized potential in healthcare to support objective and accurate interpretation of the clinical imaging. In 2008, the National Cancer Institute began building the Quantitative Imaging Network (QIN) initiative with the goal of advancing quantitative imaging in the context of personalized therapy and evaluation of treatment response. Computerized analysis is an important component contributing to reproducibility and efficiency of the quantitative imaging techniques. The success of quantitative imaging is contingent on robust analysis methods and software tools to bring these methods from bench to bedside. 3D Slicer is a free open source software application for medical image computing. As a clinical research tool, 3D Slicer is similar to a radiology workstation that supports versatile visualizations but also provides advanced functionality such as automated segmentation and registration for a variety of application domains. Unlike a typical radiology workstation, 3D Slicer is free and is not tied to specific hardware. As a programming platform, 3D Slicer facilitates translation and evaluation of the new quantitative methods by allowing the biomedical researcher to focus on the implementation of the algorithm, and providing abstractions for the common tasks of data communication, visualization and user interface development. Compared to other tools that provide aspects of this functionality, 3D Slicer is fully open source and can be readily extended and redistributed. In addition, 3D Slicer is designed to facilitate the development of new functionality in the form of 3D Slicer extensions. In this paper, we present an overview of 3D Slicer as a platform for prototyping, development and evaluation of image analysis tools for clinical research applications. To illustrate the utility of the platform in the scope of QIN, we discuss several use cases of 3D Slicer by the existing QIN teams, and we elaborate on the future

  2. 3D Slicer as an image computing platform for the Quantitative Imaging Network.

    PubMed

    Fedorov, Andriy; Beichel, Reinhard; Kalpathy-Cramer, Jayashree; Finet, Julien; Fillion-Robin, Jean-Christophe; Pujol, Sonia; Bauer, Christian; Jennings, Dominique; Fennessy, Fiona; Sonka, Milan; Buatti, John; Aylward, Stephen; Miller, James V; Pieper, Steve; Kikinis, Ron

    2012-11-01

    Quantitative analysis has tremendous but mostly unrealized potential in healthcare to support objective and accurate interpretation of the clinical imaging. In 2008, the National Cancer Institute began building the Quantitative Imaging Network (QIN) initiative with the goal of advancing quantitative imaging in the context of personalized therapy and evaluation of treatment response. Computerized analysis is an important component contributing to reproducibility and efficiency of the quantitative imaging techniques. The success of quantitative imaging is contingent on robust analysis methods and software tools to bring these methods from bench to bedside. 3D Slicer is a free open-source software application for medical image computing. As a clinical research tool, 3D Slicer is similar to a radiology workstation that supports versatile visualizations but also provides advanced functionality such as automated segmentation and registration for a variety of application domains. Unlike a typical radiology workstation, 3D Slicer is free and is not tied to specific hardware. As a programming platform, 3D Slicer facilitates translation and evaluation of the new quantitative methods by allowing the biomedical researcher to focus on the implementation of the algorithm and providing abstractions for the common tasks of data communication, visualization and user interface development. Compared to other tools that provide aspects of this functionality, 3D Slicer is fully open source and can be readily extended and redistributed. In addition, 3D Slicer is designed to facilitate the development of new functionality in the form of 3D Slicer extensions. In this paper, we present an overview of 3D Slicer as a platform for prototyping, development and evaluation of image analysis tools for clinical research applications. To illustrate the utility of the platform in the scope of QIN, we discuss several use cases of 3D Slicer by the existing QIN teams, and we elaborate on the future

  3. Quasi-3D Resistivity Imaging - Results from Geophysical Mapping and Forward Modeling

    NASA Astrophysics Data System (ADS)

    Schwindt, D.; Kneisel, C.

    2009-04-01

    2D resistivity tomography has proven to be a reliable tool in detecting, characterizing and mapping of permafrost, especially in joint application with other geophysical methods, e.g. seismic refraction. For many permafrost related problems a 3D image of the subsurface is of interest. Possibilities of quasi-3D imaging by collating several 2D ERT files into one quasi-3D file were tested. Data acquisition took place on a vegetated scree slope with isolated permafrost lenses in the Bever Valley, Swiss Alps. 21 2D-electrical arrays were applied with an electrode spacing of 5 m and a parallel spacing of 20 and 30 m using the Wenner electrode configuration. Refraction seismic was applied parallel to every second ERT array, with a geophone spacing of 5 m for validation. Results of quasi-3D imaging indicate that the most important factors influencing data quality are parallel spacing and number of right-angled crossing profiles. While the quasi-3D images generated of 2D-files with a parallel spacing of 20 m provide an interpretable image, 30 m spacing results in a blurred illustration of resistivity structures. To test the influence of crossing profiles quasi-3D images were inverted using only parallel measured data files as well as images containing right-angled crossing transects. Application of crossing profiles is of great importance, because the number of model blocks with interpolated resistivity values between parallel profiles is minimized. In case of two adjacent high resistivity anomalies a quasi-3D image consisting of parallel measured transects only illustrates one anomaly. A crossing profile provides information to differentiate the anomalies. Forward modeling was used to prove these assumptions and to improve the application of 2D ERT with regard to quasi-3D imaging. Main focus was on electrode and parallel spacing, the influence of crossing transects and the applicability of different array types. A number of 2D ERT profiles were generated, using the forward

  4. Improving Geologic and Engineering Models of Midcontinent Fracture and Karst-Modified Reservoirs Using New 3-D Seismic Attributes

    SciTech Connect

    Susan Nissen; Saibal Bhattacharya; W. Lynn Watney; John Doveton

    2009-03-31

    Our project goal was to develop innovative seismic-based workflows for the incremental recovery of oil from karst-modified reservoirs within the onshore continental United States. Specific project objectives were: (1) to calibrate new multi-trace seismic attributes (volumetric curvature, in particular) for improved imaging of karst-modified reservoirs, (2) to develop attribute-based, cost-effective workflows to better characterize karst-modified carbonate reservoirs and fracture systems, and (3) to improve accuracy and predictiveness of resulting geomodels and reservoir simulations. In order to develop our workflows and validate our techniques, we conducted integrated studies of five karst-modified reservoirs in west Texas, Colorado, and Kansas. Our studies show that 3-D seismic volumetric curvature attributes have the ability to re-veal previously unknown features or provide enhanced visibility of karst and fracture features compared with other seismic analysis methods. Using these attributes, we recognize collapse features, solution-enlarged fractures, and geomorphologies that appear to be related to mature, cockpit landscapes. In four of our reservoir studies, volumetric curvature attributes appear to delineate reservoir compartment boundaries that impact production. The presence of these compartment boundaries was corroborated by reservoir simulations in two of the study areas. Based on our study results, we conclude that volumetric curvature attributes are valuable tools for mapping compartment boundaries in fracture- and karst-modified reservoirs, and we propose a best practices workflow for incorporating these attributes into reservoir characterization. When properly calibrated with geological and production data, these attributes can be used to predict the locations and sizes of undrained reservoir compartments. Technology transfer of our project work has been accomplished through presentations at professional society meetings, peer-reviewed publications

  5. 3D Seismic Velocity Structure Around Philippine Sea Slab Subducting Beneath Kii Peninsula, Japan

    NASA Astrophysics Data System (ADS)

    Shibutani, T.; Imai, M.; Hirahara, K.; Nakao, S.

    2013-12-01

    Kii Peninsula is a part of the source area of Nankai Trough megaquakes and the region through which the strong seismic waves propagate to big cities in Kansai such as Osaka, Kyoto, Nara, Kobe, and so on. Moreover, the rupture starting point is thought to be possibly at off the peninsula. Therefore, it is important for simulations of the megaquakes and the strong motions to estimate accurately the configuration of the Philippine Sea slab and the seismic velocity structure around the slab and to investigate properties and conditions of the plate boundary surface. Deep low frequency events (DLFEs) are widely distributed from western Shikoku to central Tokai at 30 - 40 km depths on the plate boundary (Obara, 2002). Results from seismic tomography and receiver function analyses revealed that the oceanic crust of the Philippine Sea plate had a low velocity and a high Vp/Vs ratio (Hirose et al., 2007; Ueno et al., 2008). Hot springs with high 3He/4He ratios are found in an area between central Kinki and Kii Peninsula despite in the forearc region (Sano and Wakita, 1985). These phenomena suggest the process that H2O subducting with the oceanic crust dehydrates at the depths, causes the DLFEs, and moves to shallower depths. We carried out linear array seismic observations in the Kii Peninsula since 2004 in order to estimate the structure of the Philippine Sea slab and the surrounding area. We have performed receiver function analyses for four profile lines in the dipping direction of the slab and two lines in the perpendicular direction so far. We estimated three dimensional shapes of seismic velocity discontinuities such as the continental Moho, the upper surface of the oceanic crust and the oceanic Moho (Imai et al., 2013, this session). In addition, we performed seismic tomography with a velocity model embedded the discontinuities and observed travel times at stations in the linear arrays, and successfully estimated 3D seismic velocity structure around the Philippine Sea

  6. Codeless GPS systems for positioning of offshore platforms and 3D seismic surveys

    NASA Astrophysics Data System (ADS)

    MacDoran, P. F.; Miller, R. B.; Buennagel, L. A.; Fliegel, H. F.; Tanida, L.

    The Satellite Emission Range Inferred Earth Surveying (SERIES) method was originally intended for subdecimeter accuracy measurements of the crust of the earth in search of tell-tale patterns which could be exploited for research into earthquake prediction. The present paper is concerned with a specific application of the SERIES technology, taking into account high accuracy positioning related to exploration for oil and gas reserves in the offshore environment. One of the most advanced methods of exploration for hydrocarbon resources is known as 3D seismic surveying. Morgan (1983) has discussed this method, giving attention to the possible benefits of using the Global Positioning System (GPS). The present paper presents the SERIES-GPS method. It is shown that wide civil use of the Navstar is possible to levels of accuracy well beyond the Precise Positioning Service (PPS). Such a use is feasible without the DOD for Navstar codes and orbits.

  7. Lithology Cubes and Geobodies from 3D Seismic Data - a Gulf of Mexico Case Study

    NASA Astrophysics Data System (ADS)

    Shelander, D. L.; Zhang, L.; Jacob, C.; Biles, N. E.

    2012-12-01

    Seismic data can be expressed in terms of lithology by utilizing a conversion process which was applied in a case study from the Gulf of Mexico shelf. This process uses rock physics analyses from well data to establish relationships between observed lithology/pore fluid types and physical properties that can be inverted from pre-stack seismic data, e.g. acoustic impedance, P-wave/S-wave velocity ratio (Vp/Vs), and density. Saturation of water (Sw) and volume of shale (Vshale) limits were used to define four lithology/fluid classes (litho-class) in terms of the physical properties; hydrocarbon (HC) sand, wet sand, shaly sand, and shale. Bayesian derived probability density functions (PDFs) for each litho-class were calculated from well log computations of acoustic impedance, Vp/Vs, and density. Using the PDFs, probability cubes for the individual lithologies are calculated from the seismic derived acoustic impedance, Vp/Vs, and density cubes. LithoCube probability cubes are calculated for 4 different litho-classes, and used to determine two additional cubes, a maximum probability cube and a ClassCube. Thus, six LithoCube volumes were generated: ClassCube (comprising the 4 litho-classes, plus an undefined class, assigned based on the highest probability for each sample), Maximum Probability (the value of the highest probability found for each sample, values 0-1.0), Probability of shale (values 0-1.0), Probability of shaly sand (values 0-1.0), Probability of wet sand (values 0-1.0), and Probability of HC sand (values 0 -1.0) The ClassCube provides a quick look, indicating which of the 4 lithology types is most probable for any one sample in the 3D cubes. The Probability for HC sand cube is very useful because it shows probability levels for HC sand occurrence. For example with the four litho-classes, probability for the HC sand may be as high as 1.0, or as low as 0.26. For 0.26 values, the probabilities for the other 3 litho-classes can be 0.25, 0.25 and 0.24. Both of

  8. An overview of results from the CO2SINK 3D baseline seismic survey at Ketzin, Germany

    NASA Astrophysics Data System (ADS)

    Juhlin, C.; Giese, R.; Cosma, C.; Kazemeini, H.; Juhojuntti, N.; Lüth, S.; Norden, B.; Förster, A.; Yordkayhun, S.

    2009-04-01

    A 3D seismic survey was acquired at the CO2SINK project site over the Ketzin anticline in the fall of 2005. Main objectives of the survey were (1) to verify earlier geological interpretations of the structure based on vintage 2D seismic and borehole data, (2) to provide, if possible, an understanding of the structural geometry for flow pathways within the reservoir, (3) a baseline for later evaluation of the time evolution of rock properties as CO2 is injected into the reservoir, and (4) detailed sub-surface images near the injection borehole for planning of the drilling operations. Overlapping templates with 5 receiver lines containing 48 active channels in each template were used for the acquisition. In each template, 200 nominal source points were activated using an accelerated weight drop, giving a nominal fold of 25. Due to logistics, the number of actual source points in each template varied. In spite of the relatively low fold and the simple source used, data quality is generally good with the uppermost 1000 m being well imaged. Data processing results clearly show a fault system across the top of the Ketzin anticline that is termed the Central Graben Fault Zone (CGFZ). The fault zone consists of west-southwest-east-northeast- to east-west-trending normal faults bounding a 600-800 m wide graben. Within the Jurassic section, discrete faults are well developed, and the main graben-bounding faults have throws of up to 30 m. At shallower levels, the fault system appears to disappear in the Tertiary Rupelian clay. The main bounding faults of the CGFZ can be traced downwards to the top of the Weser Formation and possibly to the Stuttgart level, the target formation for CO2 injection. No faults were imaged near the injection site on the southern limb of the anticline. Remnant gas, cushion and residual gas from a previous natural gas storage facility at the site, is present near the top of the anticline in the depth interval of about 250-400 m and has a clear

  9. ROIC for gated 3D imaging LADAR receiver

    NASA Astrophysics Data System (ADS)

    Chen, Guoqiang; Zhang, Junling; Wang, Pan; Zhou, Jie; Gao, Lei; Ding, Ruijun

    2013-09-01

    Time of flight laser range finding, deep space communications and scanning video imaging are three applications requiring very low noise optical receivers to achieve detection of fast and weak optical signal. HgCdTe electrons initiated avalanche photodiodes (e-APDs) in linear multiplication mode is the detector of choice thanks to its high quantum efficiency, high gain at low bias, high bandwidth and low noise factor. In this project, a readout integrated circuit of hybrid e-APD focal plane array (FPA) with 100um pitch for 3D-LADAR was designed for gated optical receiver. The ROIC works at 77K, including unit cell circuit, column-level circuit, timing control, bias circuit and output driver. The unit cell circuit is a key component, which consists of preamplifier, correlated double Sampling (CDS), bias circuit and timing control module. Specially, the preamplifier used the capacitor feedback transimpedance amplifier (CTIA) structure which has two capacitors to offer switchable capacitance for passive/active dual mode imaging. The main circuit of column-level circuit is a precision Multiply-by-Two circuit which is implemented by switched-capacitor circuit. Switched-capacitor circuit is quite suitable for the signal processing of readout integrated circuit (ROIC) due to the working characteristics. The output driver uses a simply unity-gain buffer. Because the signal is amplified in column-level circuit, the amplifier in unity-gain buffer uses a rail-rail amplifier. In active imaging mode, the integration time is 80ns. Integrating current from 200nA to 4uA, this circuit shows the nonlinearity is less than 1%. In passive imaging mode, the integration time is 150ns. Integrating current from 1nA to 20nA shows the nonlinearity less than 1%.

  10. 3D imaging of enzymes working in situ.

    PubMed

    Jamme, F; Bourquin, D; Tawil, G; Viksø-Nielsen, A; Buléon, A; Réfrégiers, M

    2014-06-01

    Today, development of slowly digestible food with positive health impact and production of biofuels is a matter of intense research. The latter is achieved via enzymatic hydrolysis of starch or biomass such as lignocellulose. Free label imaging, using UV autofluorescence, provides a great tool to follow one single enzyme when acting on a non-UV-fluorescent substrate. In this article, we report synchrotron DUV fluorescence in 3-dimensional imaging to visualize in situ the diffusion of enzymes on solid substrate. The degradation pathway of single starch granules by two amylases optimized for biofuel production and industrial starch hydrolysis was followed by tryptophan autofluorescence (excitation at 280 nm, emission filter at 350 nm). The new setup has been specially designed and developed for a 3D representation of the enzyme-substrate interaction during hydrolysis. Thus, this tool is particularly effective for improving knowledge and understanding of enzymatic hydrolysis of solid substrates such as starch and lignocellulosic biomass. It could open up the way to new routes in the field of green chemistry and sustainable development, that is, in biotechnology, biorefining, or biofuels. PMID:24796213

  11. A Robust MEMS Based Multi-Component Sensor for 3D Borehole Seismic Arrays

    SciTech Connect

    Paulsson Geophysical Services

    2008-03-31

    The objective of this project was to develop, prototype and test a robust multi-component sensor that combines both Fiber Optic and MEMS technology for use in a borehole seismic array. The use such FOMEMS based sensors allows a dramatic increase in the number of sensors that can be deployed simultaneously in a borehole seismic array. Therefore, denser sampling of the seismic wave field can be afforded, which in turn allows us to efficiently and adequately sample P-wave as well as S-wave for high-resolution imaging purposes. Design, packaging and integration of the multi-component sensors and deployment system will target maximum operating temperature of 350-400 F and a maximum pressure of 15000-25000 psi, thus allowing operation under conditions encountered in deep gas reservoirs. This project aimed at using existing pieces of deployment technology as well as MEMS and fiber-optic technology. A sensor design and analysis study has been carried out and a laboratory prototype of an interrogator for a robust borehole seismic array system has been assembled and validated.

  12. Use of Low-cost 3-D Images in Teaching Gross Anatomy.

    ERIC Educational Resources Information Center

    Richards, Boyd F.; And Others

    1987-01-01

    With advances in computer technology, it has become possible to create three-dimensional (3-D) images of anatomical structures for use in teaching gross anatomy. Reported is a survey of attitudes of 91 first-year medical students toward the use of 3-D images in their anatomy course. Reactions to the 3-D images and suggestions for improvement are…

  13. LLNL's 3-D A Priori Model Constraints and Uncertainties for Improving Seismic Location

    SciTech Connect

    Flanagan, M P; Myers, S C; Schultz, C A; Pasyanos, M E; Bhattacharyya, J

    2000-07-14

    Accurate seismic event location is key to monitoring the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and is largely dependent on our understanding of the crust and mantle velocity structure. This is particularly challenging in aseismic regions, devoid of calibration data, which leads us to rely on a priori constraints on the velocities. We investigate our ability to improve seismic event location in the Middle East, North Africa, and the Former Soviet Union (ME/NA/FSU) by using a priori three-dimensional (3-D) velocity models in lieu of more commonly used one dimensional (1-D) models. Event locations based on 1-D models are often biased, as they do not account for significant travel-time variations that result from heterogeneous crust and mantle; it follows that 3-D velocity models have the potential to reduce this bias. Here, we develop a composite 3-D model for the ME/NA/FSU regions. This fully 3-D model is an amalgamation of studies ranging from seismic reflection to geophysical analogy. Our a priori model specifies geographic boundaries and velocity structures based on geology, tectonics, and seismicity and information taken from published literature, namely a global sediment thickness map of 1{sup o} resolution (Laske and Masters, 1997), a regionalized crustal model based on geology and tectonics (Sweeney and Walter, 1998; Bhattacharyya et al., 2000; Walter et al., 2000), and regionalized upper mantle (RUM) models developed from teleseismic travel times (Gudmundsson and Sambridge, 1998). The components of this model were chosen for the complementary structures they provide. The 1{sup o} sediment map and regionalized crustal model provide detailed structures and boundaries not available in the more coarse 5{sup o} models used for global-scale studies. The RUM models offer improved resolution over global tomography, most notably above depths of 300 km where heterogeneity is greatest; however, we plan to test other published upper mantle models of both P- and S

  14. Refining seismic parameters in low seismicity areas by 3D trenching: The Alhama de Murcia fault, SE Iberia

    NASA Astrophysics Data System (ADS)

    Ferrater, Marta; Ortuño, Maria; Masana, Eulàlia; Pallàs, Raimon; Perea, Hector; Baize, Stephane; García-Meléndez, Eduardo; Martínez-Díaz, José J.; Echeverria, Anna; Rockwell, Thomas K.; Sharp, Warren D.; Medialdea, Alicia; Rhodes, Edward J.

    2016-06-01

    Three-dimensional paleoseismology in strike-slip faults with slip rates less than 1 mm per year involves a great methodological challenge. We adapted 3D trenching to track buried channels offset by the Alhama de Murcia seismogenic left-lateral strike-slip fault (SE Iberia). A fault net slip of 0.9 ± 0.1 mm/yr was determined using statistical analysis of piercing lines for one buried channel, whose age is constrained between 15.2 ± 1.1 ka and 21.9-22.3 cal BP. This value is larger and more accurate than the previously published slip rates for this fault. The minimum number of five paleo-earthquakes identified since the deposition of dated layers suggests a maximum average recurrence interval of approximately 5 ka. The combination of both seismic parameters yields a maximum slip per event between 5.3 and 6.3 m. We show that accurately planned trenching strategies and data processing may be key to obtaining robust paleoseismic parameters in low seismicity areas.

  15. Surface amplitude data: 3D-seismic for interpretation of sea floor geology (Louisiana Slope)

    SciTech Connect

    Roberts, H.H.

    1996-09-01

    Proliferation of 3D-seismic in support of hydrocarbon exploration/production has created new data for improved interpretation of sea floor and shallow subsurface geology. Processing of digital seismic data to enhance amplitude anomalies produces information for improved assessment of geohazards and identification of sensitive benthic communities protected by environmental regulations. Coupled with high resolution acoustic data and direct observation/sampling using a manned research submersible, surface amplitude maps add critical interpretive information for identification of sea floor features. Non-reflective zones (acoustic wipeouts) are associated with many slope features. Mud diapirs, mud mounds, mud volcanoes, gas-changed sediments, gas hydrates, slump deposits, carbonate hardgrounds, and various types of carbonate mounds are all features that exhibit this common response on high resolution seismic profiles. Amplitude data help make specific identifications. Since 1988, submersible data from mid-to-upper slope features (Garden Banks, Green Canyon, and Mississippi Canyon lease block areas) have been analyzed with conventional high resolution acoustic data and 313-amplitude extraction maps. Areas of rapid venting of sediment and hydrocarbon-charged formation fluids are clearly distinguishable from mud diapirs and areas of carbonate mounds (slow seepage). Gas hydrates occur as mounds and mounded zones along faults; products of moderate flux rates below (approx.) 500 in water depths. Gas hydrates function as stored trophic resources that support sensitive chemosynthetic communities. Amplitude extraction maps clearly identify these features by a strong low impedance amplitude anomaly. Refinement and {open_quotes}field calibration{close_quotes} of the surface amplitude extraction method may eventually lead to a new standard for evaluating geohazards and sensitive benthic communities.

  16. Numerical homogenization for seismic wave propagation in 3D geological media

    NASA Astrophysics Data System (ADS)

    Cupillard, P.; Capdeville, Y.; Botella, A.

    2014-12-01

    Despite the important increase of the computational power in the last decades, simulating the seismic wave propagation through realistic geological models is still a challenge. By realistic models we here mean 3D media in which a broad variety (in terms of amplitude and extent) of heterogeneities lies, including discontinuities with complex geometry such as faulted and folded horizons, intrusive geological contacts and fault systems. To perform accurate numerical simulations, these discontinuities require complicated meshes which usually contain extremely small elements, yielding large, sometimes prohibitive, computation costs. Fortunately, the recent development of the non-periodic homogenization technique now enables to overcome this problem by computing smooth equivalent models for which a coarse mesh is sufficient to get an accurate wavefield. In this work, we present an efficient implementation of the technique which now allows for the homogenization of large 3D geological models. This implementation relies on a tetrahedral finite-element solution of the elasto-static equation behind the homogenization problem. Because this equation is time-independent, solving it is numerically cheaper than solving the wave equation, but it nevertheless requires some care because of the large size of the stiffness matrix arising from the fine mesh of realistic geological structures. A domain decomposition is therefore adopted. In our strategy, the obtained sub-domains overlap but they are independent so the solution within each of them can be computed either in series or in parallel. In addition, well-balanced loads, efficient search algorithms and multithreading are implemented to speed up the computation. The resulting code enables the homogenization of 3D elastic media in a time that is neglectable with respect to the simulation time of the wave propagation within. This is illustrated through a sub-surface model of the Furfooz karstic region, Belgium.

  17. Modeling the Coast Mountains Batholith, British Columbia, Canada with 3D Seismic Tomography

    NASA Astrophysics Data System (ADS)

    Quinonez, S. M.; Olaya, J. C.; Miller, K. C.; Romero, R.; Velasco, A. A.; Harder, S. H.; Cerda, I.

    2011-12-01

    The Coast Mountains Batholith on the west coast of British Columbia, Canada comprises a series of granitic to tonalitic plutons; where felsic continental crust is generated from the subduction of mafic oceanic crust by partial melting and fractionation, leaving ultra-mafic roots. In July of 2009, a large controlled-source experiment was conducted along a 400km east - west transect from Bella Bella into central British Columbia. Student volunteers from multiple universities deployed 1,800 one-component and 200 three-component geophones plus 2400 Texan data recorders with 200-m spacing intervals and shot spacing at 30-km. The 18-point sources ranged from 160 to 1,000 kg of high explosive. The geoscience component of the NSF-funded Cyber-ShARE project at UTEP focuses on fusing models developed from different data sets to develop 3-D Earth models. Created in 2007, the Cyber-ShARE Center brings together experts in computer science, computational mathematics, education, earth science, and environmental science. We leverage the Cyber-ShARE work to implement an enhanced 3-D finite difference tomography approach for P-wave delays times (Hole, 1992) with a graphical user interface and visualization framework. In particular, to account for model sensitivity to picked P-wave arrival times, we use a model fusion approach (Ochoa et al., 2010) to generate a model with the lowest RMS residual that a combination of a set of Monte Carlo sample models. In order to make the seismic tomography process more interactive at many points, visualizations of model perturbation at each iteration will help to troubleshoot when a model is not converging to highlight where the RMS residual values are the highest to pinpoint where changes need to be made to achieve model convergence. Finally, a model of the upper mantle using 3-D P-wave tomography will be made to determine the location of these ultra-mafic roots.

  18. The Role of Faulting on the Growth of a Carbonate Platform: Evidence from 3D Seismic Analysis and Section Restoration

    NASA Astrophysics Data System (ADS)

    Nur Fathiyah Jamaludin, Siti; Pubellier, Manuel; Prasad Ghosh, Deva; Menier, David; Pierson, Bernard

    2014-05-01

    Tectonics in addition to other environmental factors impacts the growth of carbonate platforms and plays an important role in shaping the internal architecture of the platforms. Detailed of faults and fractures development and healing in carbonate environment have not been explored sufficiently. Using 3D seismic and well data, we attempt to reconstruct the structural evolution of a Miocene carbonate platform in Central Luconia Province, offshore Malaysia. Luconia Province is located in the NW coast of Borneo and has become one of the largest carbonate factories in SE Asia. Seismic interpretations including seismic attribute analysis are applied to the carbonate platform to discern its sedimentology and structural details. Detailed seismic interpretations highlight the relationships of carbonate deposition with syn-depositional faulting. Branching conjugate faults are common in this carbonate platform and have become a template for reef growth, attesting lateral facies changes within the carbonate environments. Structural restoration was then appropriately performed on the interpreted seismic sections based on sequential restoration techniques, and provided images different from those of horizon flattening methods. This permits us to compensate faults' displacement, remove recent sediment layers and finally restore the older rock units prior to the fault motions. It allows prediction of platform evolution as a response to faulting before and after carbonate deposition and also enhances the pitfalls of interpretation. Once updated, the reconstructions allow unravelling of the un-seen geological features underneath the carbonate platform, such as paleo-structures and paleo-topography which in turn reflects the paleo-environment before deformations took place. Interestingly, sections balancing and restoration revealed the late-phase (Late Oligocene-Early Miocene) rifting of South China Sea, otherwise difficult to visualize on seismic sections. Later it is shown that

  19. Full Waveform 3D Synthetic Seismic Algorithm for 1D Layered Anelastic Models

    NASA Astrophysics Data System (ADS)

    Schwaiger, H. F.; Aldridge, D. F.; Haney, M. M.

    2007-12-01

    Numerical calculation of synthetic seismograms for 1D layered earth models remains a significant aspect of amplitude-offset investigations, surface wave studies, microseismic event location approaches, and reflection interpretation or inversion processes. Compared to 3D finite-difference algorithms, memory demand and execution time are greatly reduced, enabling rapid generation of seismic data within workstation or laptop computational environments. We have developed a frequency-wavenumber forward modeling algorithm adapted to realistic 1D geologic media, for the purpose of calculating seismograms accurately and efficiently. The earth model consists of N layers bounded by two halfspaces. Each layer/halfspace is a homogeneous and isotropic anelastic (attenuative and dispersive) solid, characterized by a rectangular relaxation spectrum of absorption mechanisms. Compressional and shear phase speeds and quality factors are specified at a particular reference frequency. Solution methodology involves 3D Fourier transforming the three coupled, second- order, integro-differential equations for particle displacements to the frequency-horizontal wavenumber domain. An analytic solution of the resulting ordinary differential system is obtained. Imposition of welded interface conditions (continuity of displacement and stress) at all interfaces, as well as radiation conditions in the two halfspaces, yields a system of 6(N+1) linear algebraic equations for the coefficients in the ODE solution. An optimized inverse 2D Fourier transform to the space domain gives the seismic wavefield on a horizontal plane. Finally, three-component seismograms are obtained by accumulating frequency spectra at designated receiver positions on this plane, followed by a 1D inverse FFT from angular frequency ω to time. Stress-free conditions may be applied at the top or bottom interfaces, and seismic waves are initiated by force or moment density sources. Examples reveal that including attenuation

  20. Interpretation of a 3D Seismic-Reflection Volume in the Basin and Range, Hawthorne, Nevada

    NASA Astrophysics Data System (ADS)

    Louie, J. N.; Kell, A. M.; Pullammanappallil, S.; Oldow, J. S.; Sabin, A.; Lazaro, M.

    2009-12-01

    A collaborative effort by the Great Basin Center for Geothermal Energy at the University of Nevada, Reno, and Optim Inc. of Reno has interpreted a 3d seismic data set recorded by the U.S. Navy Geothermal Programs Office (GPO) at the Hawthorne Army Depot, Nevada. The 3d survey incorporated about 20 NNW-striking lines covering an area of approximately 3 by 10 km. The survey covered an alluvial area below the eastern flank of the Wassuk Range. In the reflection volume the most prominent events are interpreted to be the base of Quaternary alluvium, the Quaternary Wassuk Range-front normal fault zone, and sequences of intercalated Tertiary volcanic flows and sediments. Such a data set is rare in the Basin and Range. Our interpretation reveals structural and stratigraphic details that form a basis for rapid development of the geothermal-energy resources underlying the Depot. We interpret a map of the time-elevation of the Wassuk Range fault and its associated splays and basin-ward step faults. The range-front fault is the deepest, and its isochron map provides essentially a map of "economic basement" under the prospect area. There are three faults that are the most readily picked through vertical sections. The fault reflections show an uncertainty in the time-depth that we can interpret for them of 50 to 200 ms, due to the over-migrated appearance of the processing contractor’s prestack time-migrated data set. Proper assessment of velocities for mitigating the migration artifacts through prestack depth migration is not possible from this data set alone, as the offsets are not long enough for sufficiently deep velocity tomography. The three faults we interpreted appear as gradients in potential-field maps. In addition, the southern boundary of a major Tertiary graben may be seen within the volume as the northward termination of the strong reflections from older Tertiary volcanics. Using a transparent volume view across the survey gives a view of the volcanics in full

  1. Zonation of North Alex Mud Volcano Highlighted by 3-D Active and Passive Seismic Data

    NASA Astrophysics Data System (ADS)

    Bialas, J.; Lefeldt, M. R.; Klaeschen, D.; Papenberg, C. A.; Brueckmann, W.

    2010-12-01

    The West Nile Delta forms part of the source of the large turbiditic Nile Deep Sea Fan. Since the late Miocene sediments have formed an up to 10 km thick pile, which includes about 1 - 3 km of Messinian evaporates. The sediment load of the overburden implies strong overpressures and salt-related tectonic deformation. Both are favourable for fluid migration towards the seafloor guided by the fractured margin. The western deltaic system, Rosetta branch, has formed an 80 km wide continental shelf. Here at 700 m water depth the mud volcano North Alex (NA) developed his circular bathymetric feature, which proved to be an active gas and mud-expelling structure. A 3-D high-resolution multichannel seismic survey (IFM-GEOMAR P-Cable system) was completed across the mud volcano. 3-D time migration provided a 3-D data cube with a 6.25 m grid. Vertical seismic sections did reveal a large set of faults located within the main mud volcano as well as surrounding the structure. Internal faults are mainly related to episodic mud expulsion processes and continuous gas and fluid production. Deep cutting external faults surround the structure in a half circle shape. Horizontal amplitude maps (time slices) of indicate recent activity of these faults even up to the seafloor. High gas saturation of the sediments is indicated by inverted reflection events. In the centre the gas front cuts into the seafloor reflection while it dips down with increasing radius. Only with the small grid resolution inward dipping reflections become visible, which form an upward opened concave reflector plane underlying the top gas front. The interpretation assumes an oval lens shaped body (conduit) saturated with gas at the top of the mud volcano. It provides the upper termination of the mud chimney. This separation is further supported by passive seismic observations. Distant earthquakes can stimulate long-period harmonic oscillations in mud volcanoes. Such oscillations are detectable with three

  2. 3D seismic analysis of gravity-driven and basement influenced normal fault growth in the deepwater Otway Basin, Australia

    NASA Astrophysics Data System (ADS)

    Robson, A. G.; King, R. C.; Holford, S. P.

    2016-08-01

    We use three-dimensional (3D) seismic reflection data to analyse the structural style and growth of a normal fault array located at the present-day shelf-edge break and into the deepwater province of the Otway Basin, southern Australia. The Otway Basin is a Late Jurassic to Cenozoic, rift-to-passive margin basin. The seismic reflection data images a NW-SE (128-308) striking, normal fault array, located within Upper Cretaceous clastic sediments and which consists of ten fault segments. The fault array contains two hard-linked fault assemblages, separated by only 2 km in the dip direction. The gravity-driven, down-dip fault assemblage is entirely contained within the 3D seismic survey, is located over a basement plateau and displays growth commencing and terminating during the Campanian-Maastrichtian, with up to 1.45 km of accumulated throw (vertical displacement). The up-dip normal fault assemblage penetrates deeper than the base of the seismic survey, but is interpreted to be partially linked along strike at depth to major basement-involved normal faults that can be observed on regional 2D seismic lines. This fault assemblage displays growth initiating in the Turonian-Santonian and has accumulated up to 1.74 km of throw. Our detailed analysis of the 3D seismic data constraints post-Cenomanian fault growth of both fault assemblages into four evolutionary stages: [1] Turonian-Santonian basement reactivation during crustal extension between Australia and Antarctica. This either caused the upward propagation of basement-involved normal faults or the nucleation of a vertically isolated normal fault array in shallow cover sediments directly above the reactivated basement-involved faults; [2] continued Campanian-Maastrichtian crustal extension and sediment loading eventually created gravitational instability on the basement plateau, nucleating a second, vertically isolated normal fault array in the cover sediments; [3] eventual hard-linkage of fault segments in both fault

  3. Improvements of 3-D image quality in integral display by reducing distortion errors

    NASA Astrophysics Data System (ADS)

    Kawakita, Masahiro; Sasaki, Hisayuki; Arai, Jun; Okano, Fumio; Suehiro, Koya; Haino, Yasuyuki; Yoshimura, Makoto; Sato, Masahito

    2008-02-01

    An integral three-dimensional (3-D) system based on the principle of integral photography can display natural 3-D images. We studied ways of improving the resolution and viewing angle of 3-D images by using extremely highresolution (EHR) video in an integral 3-D video system. One of the problems with the EHR projection-type integral 3-D system is that positional errors appear between the elemental image and the elemental lens when there is geometric distortion in the projected image. We analyzed the relationships between the geometric distortion in the elemental images caused by the projection lens and the spatial distortion of the reconstructed 3-D image. As a result, we clarified that 3-D images reconstructed far from the lens array were greatly affected by the distortion of the elemental images, and that the 3-D images were significantly distorted in the depth direction at the corners of the displayed images. Moreover, we developed a video signal processor that electrically compensated the distortion in the elemental images for an EHR projection-type integral 3-D system. Therefore, the distortion in the displayed 3-D image was removed, and the viewing angle of the 3-D image was expanded to nearly double that obtained with the previous prototype system.

  4. Development of a 3D VHR seismic reflection system for lacustrine settings - a case study in Lake Geneva, Switzerland

    NASA Astrophysics Data System (ADS)

    Scheidhauer, M.; Dupuy, D.; Marillier, F.; Beres, M.

    2003-04-01

    For better understanding of geologic processes in complex lacustrine settings, detailed information on geologic features is required. In many cases, the 3D seismic method may be the only appropriate approach. The aim of this work is to develop an efficient very high-resolution 3D seismic reflection system for lake studies. In Lake Geneva, Switzerland, near the city of Lausanne, past high-resolution investigations revealed a complex fault zone, which was subsequently chosen for testing our new system of three 24-channel streamers and integrated differential GPS (dGPS) positioning. A survey, carried out in 9 days in August 2001, covered an area of 1500^om x 675^om and comprised 180 CMP lines sailed perpendicular to the fault strike always updip, since otherwise the asymmetric system would result in different stacks for opposite directions. Accurate navigation and shot spacing of 5^om is achieved with a specially developed navigation and shot-triggering software that uses differential GPS onboard and a reference base close to the lake shore. Hydrophone positions could be accurately (<^o0.5^om) calculated with the aid of three additional dGPS antennas mounted on rafts attached to the streamer tails. Towed at a distance of only 75^om behind the vessel, they allowed determination of possible feathering due to cross-line currents or small course variations. The multi-streamer system uses two retractable booms deployed on each side of the boat and rest on floats. They separate the two outer streamers from the one in the center by a distance of 7.5^om. Combined with a receiver spacing of 2.5^om, the bin dimension of the 3D data becomes 3.75^om in cross-line and 1.25^om in inline direction. Potential aliasing problems from steep reflectors up to 30^o within the fault zone motivated the use of a 15/15 cu. in. double-chamber bubble-canceling Mini G.I. air gun (operated at 80^obars and 1^om depth). Although its frequencies do not exceed 650^o Hz, it combines a penetration of

  5. High resolution processing of 3D seismic data for thin coal seam in Guqiao coal mine

    NASA Astrophysics Data System (ADS)

    Li, Qiaoling; Peng, Suping; Zou, Guangui

    2015-04-01

    Accurate identification of small faults for coal seams is very important for coal-field exploration, which can greatly improve mining efficiency and safety. However, coal seams in China are mostly thin layers, ranging from 2-5 m. Moreover, the shallow coal seam with strong reflection forms a shield underneath thin coal seam which is only about 40 m deeper. This causes great difficulty in seismic processing and interpretation. The primary concern is to obtain high-resolution seismic image of underneath thin coal seam for mining safety. In this paper, field data is carefully analyzed and fit-for-purpose solutions are adopted in order to improve the quality of reprocessed data and resolution of target coal seam. Identification of small faults has been enhanced significantly.

  6. Early Pleistocene glaciations of the North Sea basin revealed by geomorphic evidence from 3D seismic datasets

    NASA Astrophysics Data System (ADS)

    Stewart, Margaret A.; Graham, Alastair G. C.; Lonergan, Lidia

    2013-04-01

    The record of the last major glaciation across northwest Europe is increasingly well understood, but the extent, timing, and palaeoenvironmental significance of earlier Pleistocene glaciations is still poorly known. Here, two sets of iceberg ploughmarks and a buried tunnel valley, all well-imaged within 3D seismic data, provide direct geomorphic evidence for glacial conditions in the central North Sea during periods of the Early to Middle Pleistocene. Each set of geomorphic features is mapped within separate stratigraphic intervals and constrained using seismic-borehole ties to the Bruhnes-Matuyama [B-M] palaeomagnetic reversal, dated in NW Europe at approximately 0.79 Ma B.P (Funnell, 1995). The first set of iceberg ploughmarks mapped within the Witch Ground Basin at approximately 0°30'W, 58°10N comprises 423 scours within a package of relatively disturbed seismic reflectors approximately 130-170m below seabed. Scours are sub-parallel, cross-cutting, and occasionally sinuous, with widths of 40-60m and lengths between 1km and 10km+. The ploughmarked surface is extensively incised by multiple generations of younger tunnel valleys imaged within the same 3D seismic data, and lies above the older B-M horizon. A second set of ploughmarks are buried approximately 250-430m beneath seabed at 2 °40'E 56 °30'N approximately180km SE of the Witch Ground Basin scours. More than 1800 individual scours are observed with widths between 50m and 100m, and lengths from 1km to 17km. The buried scours are observed within three horizons, and their stratigraphic position indicates they pre-date the B-M reversal, lying within a unit traditionally associated with times of non-glacial deposition. A single buried tunnel valley, c.60km in length, is observed towards the NW of the study area at approximately 0°30'W and 58°30'N. The main channel of the tunnel valley is curvilinear and trends approximately NE-SW with two significant tributary channels trending NW-SE. The tunnel valley

  7. Transmission of holographic 3D images using infrared transmitter(II): on a study of transmission of holographic 3D images using infrared transmitter safe to medical equipment

    NASA Astrophysics Data System (ADS)

    Takano, Kunihiko; Muto, Kenji; Tian, Lan; Sato, Koki

    2007-09-01

    An infrared transmitting technique for 3D holographic images is studied. It seems to be very effective as a transmitting technique for 3D holographic images in the places where electric wave is prohibited to be used for transmission. In this paper, we first explain our infrared transmitting system for holograms and a display system for the presentation of holographic 3D images reconstructed from the received signal. Next, we make a report on the results obtained by infrared transmission of CGH and a comparison of the real and the reconstructed 3D images in our system. As this result, it is found that reconstructed holographic 3D images do not suffer a large deterioration in the quality and highly contrasted ones can be presented.

  8. 3D imaging of nanomaterials by discrete tomography.

    PubMed

    Batenburg, K J; Bals, S; Sijbers, J; Kübel, C; Midgley, P A; Hernandez, J C; Kaiser, U; Encina, E R; Coronado, E A; Van Tendeloo, G

    2009-05-01

    The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi(2) nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively. PMID:19269094

  9. 3D Soil Images Structure Quantification using Relative Entropy

    NASA Astrophysics Data System (ADS)

    Tarquis, A. M.; Gonzalez-Nieto, P. L.; Bird, N. R. A.

    2012-04-01

    Soil voids manifest the cumulative effect of local pedogenic processes and ultimately influence soil behavior - especially as it pertains to aeration and hydrophysical properties. Because of the relatively weak attenuation of X-rays by air, compared with liquids or solids, non-disruptive CT scanning has become a very attractive tool for generating three-dimensional imagery of soil voids. One of the main steps involved in this analysis is the thresholding required to transform the original (greyscale) images into the type of binary representation (e.g., pores in white, solids in black) needed for fractal analysis or simulation with Lattice-Boltzmann models (Baveye et al., 2010). The objective of the current work is to apply an innovative approach to quantifying soil voids and pore networks in original X-ray CT imagery using Relative Entropy (Bird et al., 2006; Tarquis et al., 2008). These will be illustrated using typical imagery representing contrasting soil structures. Particular attention will be given to the need to consider the full 3D context of the CT imagery, as well as scaling issues, in the application and interpretation of this index.

  10. Image-Based 3d Reconstruction and Analysis for Orthodontia

    NASA Astrophysics Data System (ADS)

    Knyaz, V. A.

    2012-08-01

    Among the main tasks of orthodontia are analysis of teeth arches and treatment planning for providing correct position for every tooth. The treatment plan is based on measurement of teeth parameters and designing perfect teeth arch curve which teeth are to create after treatment. The most common technique for teeth moving uses standard brackets which put on teeth and a wire of given shape which is clamped by these brackets for producing necessary forces to every tooth for moving it in given direction. The disadvantages of standard bracket technique are low accuracy of tooth dimensions measurements and problems with applying standard approach for wide variety of complex orthodontic cases. The image-based technique for orthodontic planning, treatment and documenting aimed at overcoming these disadvantages is proposed. The proposed approach provides performing accurate measurements of teeth parameters needed for adequate planning, designing correct teeth position and monitoring treatment process. The developed technique applies photogrammetric means for teeth arch 3D model generation, brackets position determination and teeth shifting analysis.

  11. Probabilistic Seismic Hazard Maps of Seattle, Washington, Including 3D Sedimentary Basin Effects and Rupture Directivity: Implications of 3D Random Velocity Variations (Invited)

    NASA Astrophysics Data System (ADS)

    Frankel, A. D.; Stephenson, W. J.; Carver, D.; Odum, J.; Williams, R. A.; Rhea, S.

    2010-12-01

    We have produced probabilistic seismic hazard maps of Seattle for 1 Hz spectral acceleration, using over five hundred 3D finite-difference simulations of earthquakes on the Seattle fault, Southern Whidbey Island fault, and Cascadia subduction zone, as well as for random deep and shallow earthquakes at various locations. The 3D velocity model was validated by modeling the observed waveforms for the 2001 M6.8 Nisqually earthquake and several smaller events in the region. At these longer periods (≥ 1 sec) that are especially important to the response of buildings of ten stories or higher, seismic waves are strongly influenced by sedimentary basins and rupture directivity. We are investigating how random spatial variations in the 3D velocity model affect the simulated ground motions for M6.7 earthquakes on the Seattle fault. A fractal random variation of shear-wave velocity with a Von Karman correlation function produces spatial variations of peak ground velocity with multiple scale lengths. We find that a 3D velocity model with a 10% standard deviation in shear-wave velocity in the top 1.5 km and 5% standard deviation from 1.5-10 km depth produces variations in peak ground velocities of as much as a factor of two, relative to the case with no random variations. The model with random variations generally reduces the peak ground velocity of the forward rupture directivity pulse for sites near the fault where basin-edge focusing of S-waves occurs. It also tends to reduce the peak velocity of localized areas where basin surface waves are focused. However, the medium with random variations also causes small-scale amplification of ground motions over distances of a few kilometers. We are also evaluating alternative methods of characterizing the aleatory uncertainty in the probabilistic hazard calculations.

  12. 3D-seismic amplitude analysis of the sea floor: An important interpretive method for improved geohazards evaluations

    SciTech Connect

    Roberts, H.H.; Doyle, E.H.; Booth, J.R.; Clark, B.J.; Kaluza, M.J.; Hartsook, A.

    1996-12-31

    Evaluation of geohazards on the Louisiana continental slope using a combination of high-resolution acoustic data (standard geohazards survey data), 3D-seismic amplitude maps of the sea floor, and direct observation/sampling by a manned submersible reinforces the value of 3D-seismic amplitude data for feature identification. Amplitude extraction data from surface and near-surface horizons are valuable for establishing the links between high-resolution seismic signature and actual sea floor response, particularly in settings characterized by various types and rates of hydrocarbon venting/seepage. It was found that amplitude extraction data could accurately define the areas, configurations, and relative rates of hydrocarbon seepage (from anomaly strength and target size). In areas evaluated with 3D-seismic amplitude extraction data, this procedure provided a rapid method of identifying sites of hydrocarbon venting/seepage, their relative activities, and the likelihood of encountering sensitive chemosynthetic communities and other features such as mud vents, gas hydrate mounds, hardgrounds, and sizable buildups of authigenic carbonates. Results of this study support the value of using 3D-seismic amplitude extraction data for improving the understanding and predictability of the slope`s surface geology and seep-related benthic habitats.

  13. 3D Seismic and Magnetic characterization of the Borax Lake Hydrothermal System in the Alvord Desert, southeastern Oregon.

    NASA Astrophysics Data System (ADS)

    Hess, S.; Bradford, J.; Lyle, M.; Routh, P.; Liberty, L.; Donaldson, P.

    2004-05-01

    As part of an interdisciplinary project aiming to study the link between the physical characteristics of hydrothermal systems and biota that occupy those systems, we are conducting a detailed geophysical characterization of an active hydrothermal system. The Borax Lake Hydrothermal System (BLHS), consisting of Borax Lake and the surrounding hot springs. BLHS is located near the center of the Alvord Basin in southeastern Oregon. The Alvord Basin is a north-south trending graben in the Northern Great Basin bounded by the Steens Mountains to the west and the Trout Creek Mountains to the east. We conducted a 2D seismic survey to characterize the geologic structure of the basin, a high-resolution 3D seismic survey to characterize the geologic structure of the BLHS, and a high-resolution 3D magnetic survey to characterize any lineaments in the bedrock that might control fluid flow in the BLHS. Previous results from the 2D seismic survey show a mid-basin basement high aligned approximately with the hot springs. In this study we present the results from the high-resolution 3D seismic and magnetic survey of the BLHS. We acquired the 3D seismic data using an SKS rifle and 240 channel recording system. The seismic survey covers approximately 90,000 sq. m with a maximum inline offset aperture of 225 m, crossline aperture of 75 m, and 360 degree azimuthal coverage. The coincidental magnetic survey was collected using a Geometrics 858G cesium vapor magnetometer. We designed both surveys to span nearly 100 active hydrothermal springs, including an approximately 50 m stepover in the trend of the surface expression of the hot springs. After preliminary processing, the 3D seismic data show continuous reflections up to 300 ms (~ 480 m). The initial interpretation of features seen in the 3D data cube include: normal faults dipping to the east and west, near-surface disturbances that are consistent with the trend of the hot springs, and significant near surface velocity anomalies

  14. 3D P-wave velocity structure of the deep Galicia rifted margin: A first analysis of the Galicia 3D wide-angle seismic dataset

    NASA Astrophysics Data System (ADS)

    Bayrakci, Gaye; Minshull, Timothy A.; Davy, Richard G.; Karplus, Marianne S.; Kaeschen, Dirk; Papenberg, Cord; Krabbenhoeft, Anne; Sawyer, Dale; Reston, Timothy J.; Shillington, Donna J.; Ranero, César R.

    2014-05-01

    Galicia 3D, a reflection-refraction and long offset seismic experiment was carried out from May through September 2013, at the Galicia rifted margin (in the northeast Atlantic Ocean, west of Spain) as a collaboration between US, UK, German and Spanish groups. The 3D multichannel seismic acquisition conducted by R/V Marcus Langseth covered a 64 km by 20 km (1280 km2) zone where the main geological features are the Peridotite Ridge (PR), composed of serpentinized peridotite and thought be upper mantle exhumed to the seafloor during rifting, and the S reflector which has been interpreted to be a low angle detachment fault overlain by fault bounded, rotated, continental crustal blocks. In the 3D box, two airgun arrays of 3300 cu.in. were fired alternately (in flip-flop configuration) every 37.5 m. All shots are recorded by 44 short period four component ocean bottom seismometers (OBS) and 26 ocean bottom hydrophones (OBH) deployed and recovered by R/V Poseidon, as well as four 6 km hydrophone streamers with 12.5 m channel spacing towed by R/V Marcus Langseth. We present the preliminary results of the first arrival time tomography study which is carried out with a subset of the wide-angle dataset, in order to generate a 3D P-wave velocity volume for the entire depth sampled by the reflection data. After the relocation of OBSs and OBHs, an automatic first-arrival time picking approach is applied to a subset of the dataset, which comprises more than 5.5 million source-receiver pairs. Then, the first-arrival times are checked visually, in 3-dimensions. The a priori model used for the first-arrival time tomography is built up using information from previous seismic surveys carried out at the Galicia margin (e.g. ISE, 1997). The FAST algorithm of Zelt and Barton (1998) is used for the first-arrival time inversion. The 3D P-wave velocity volume can be used in interpreting the reflection dataset, as a starting point for migration, to quantify the thinning of the crustal layers

  15. Automated 3D renal segmentation based on image partitioning

    NASA Astrophysics Data System (ADS)

    Yeghiazaryan, Varduhi; Voiculescu, Irina D.

    2016-03-01

    Despite several decades of research into segmentation techniques, automated medical image segmentation is barely usable in a clinical context, and still at vast user time expense. This paper illustrates unsupervised organ segmentation through the use of a novel automated labelling approximation algorithm followed by a hypersurface front propagation method. The approximation stage relies on a pre-computed image partition forest obtained directly from CT scan data. We have implemented all procedures to operate directly on 3D volumes, rather than slice-by-slice, because our algorithms are dimensionality-independent. The results picture segmentations which identify kidneys, but can easily be extrapolated to other body parts. Quantitative analysis of our automated segmentation compared against hand-segmented gold standards indicates an average Dice similarity coefficient of 90%. Results were obtained over volumes of CT data with 9 kidneys, computing both volume-based similarity measures (such as the Dice and Jaccard coefficients, true positive volume fraction) and size-based measures (such as the relative volume difference). The analysis considered both healthy and diseased kidneys, although extreme pathological cases were excluded from the overall count. Such cases are difficult to segment both manually and automatically due to the large amplitude of Hounsfield unit distribution in the scan, and the wide spread of the tumorous tissue inside the abdomen. In the case of kidneys that have maintained their shape, the similarity range lies around the values obtained for inter-operator variability. Whilst the procedure is fully automated, our tools also provide a light level of manual editing.

  16. Imaging of 3D Ocean Turbulence Microstructure Using Low Frequency Acoustic Waves

    NASA Astrophysics Data System (ADS)

    Minakov, Alexander; Kolyukhin, Dmitriy; Keers, Henk

    2015-04-01

    In the past decade the technique of imaging the ocean structure with low-frequency signal (Hz), produced by air-guns and typically employed during conventional multichannel seismic data acquisition, has emerged. The method is based on extracting and stacking the acoustic energy back-scattered by the ocean temperature and salinity micro- and meso-structure (1 - 100 meters). However, a good understanding of the link between the scattered wavefield utilized by the seismic oceanography and physical processes in the ocean is still lacking. We describe theory and the numerical implementation of a 3D time-dependent stochastic model of ocean turbulence. The velocity and temperature are simulated as homogeneous Gaussian isotropic random fields with the Kolmogorov-Obukhov energy spectrum in the inertial subrange. Numerical modeling technique is employed for sampling of realizations of random fields with a given spatial-temporal spectral tensor. The model used is shown to be representative for a wide range of scales. Using this model, we provide a framework to solve the forward and inverse acoustic scattering problem using marine seismic data. Our full-waveform inversion method is based on the ray-Born approximation which is specifically suitable for the modelling of small velocity perturbations in the ocean. This is illustrated by showing a good match between synthetic seismograms computed using ray-Born and synthetic seismograms produced with a more computationally expensive finite-difference method.

  17. 3-D Seismic Methods for Geothermal Reservoir Exploration and Assessment--Summary

    SciTech Connect

    Majer, E.L.

    2003-07-14

    A wide variety of seismic methods covering the spectrum from DC to kilohertz have been employed at one time or the other in geothermal environments. The reasons have varied from exploration for a heat source to attempting to find individual fractures producing hot fluids. For the purposes here we will assume that overall objective of seismic imaging is for siting wells for successful location of permeable pathways (often fracture permeability) that are controlling flow and transport in naturally fractured reservoirs. The application could be for exploration of new resources or for in-fill/step-out drilling in existing fields. In most geothermal environments the challenge has been to separate the ''background'' natural complexity and heterogeneity of the matrix from the fracture/fault heterogeneity controlling the fluid flow. Ideally one not only wants to find the fractures, but the fractures that are controlling the flow of the fluids. Evaluated in this work is current state-of-the-art surface (seismic reflection) and borehole seismic methods (Vertical Seismic Profiling (VSP), Crosswell and Single Well) to locate and quantify geothermal reservoir characteristics. The focus is on active methods; the assumption being that accuracy is needed for successful well siting. Passive methods are useful for exploration and detailed monitoring for in-fill drilling, but in general the passive methods lack the precision and accuracy for well siting in new or step out areas. In addition, MEQ activity is usually associated with production, after the field has been taken to a mature state, thus in most cases it is assumed that there is not enough MEQ activity in unproduced areas to accurately find the permeable pathways. The premise of this review is that there may new developments in theory and modeling, as well as in data acquisition and processing, which could make it possible to image the subsurface in much more detail than 15 years ago. New understanding of the effect of

  18. Microseismic monitoring of soft-rock landslide: contribution of a 3D velocity model for the location of seismic sources.

    NASA Astrophysics Data System (ADS)

    Floriane, Provost; Jean-Philippe, Malet; Cécile, Doubre; Julien, Gance; Alessia, Maggi; Agnès, Helmstetter

    2015-04-01

    Characterizing the micro-seismic activity of landslides is an important parameter for a better understanding of the physical processes controlling landslide behaviour. However, the location of the seismic sources on landslides is a challenging task mostly because of (a) the recording system geometry, (b) the lack of clear P-wave arrivals and clear wave differentiation, (c) the heterogeneous velocities of the ground. The objective of this work is therefore to test whether the integration of a 3D velocity model in probabilistic seismic source location codes improves the quality of the determination especially in depth. We studied the clay-rich landslide of Super-Sauze (French Alps). Most of the seismic events (rockfalls, slidequakes, tremors...) are generated in the upper part of the landslide near the main scarp. The seismic recording system is composed of two antennas with four vertical seismometers each located on the east and west sides of the seismically active part of the landslide. A refraction seismic campaign was conducted in August 2014 and a 3D P-wave model has been estimated using the Quasi-Newton tomography inversion algorithm. The shots of the seismic campaign are used as calibration shots to test the performance of the different location methods and to further update the 3D velocity model. Natural seismic events are detected with a semi-automatic technique using a frequency threshold. The first arrivals are picked using a kurtosis-based method and compared to the manual picking. Several location methods were finally tested. We compared a non-linear probabilistic method coupled with the 3D P-wave model and a beam-forming method inverted for an apparent velocity. We found that the Quasi-Newton tomography inversion algorithm provides results coherent with the original underlaying topography. The velocity ranges from 500 m.s-1 at the surface to 3000 m.s-1 in the bedrock. For the majority of the calibration shots, the use of a 3D velocity model

  19. 3-D Radar Imaging Reveals Deep Structures and Buried Craters Within the Martian Polar Caps

    NASA Astrophysics Data System (ADS)

    Putzig, N. E.; Foss, F. J., II; Campbell, B. A.; Phillips, R. J.; Smith, I. B.

    2015-12-01

    We use Shallow Radar (SHARAD) observations on thousands of orbital passes by the Mars Reconnaissance Orbiter to produce fully imaged 3-D data volumes encompassing both polar ice caps of Mars. Greatly clarifying the view of subsurface features, a completed volume for Planum Boreum provides new constraints on the nature and timing of emplacement of the northern polar deposits and their relationship to climate. The standard method of mapping subsurface features with single-pass 2-D radargrams has been very fruitful (see Brothers et al. 2015, JGR 120 in press, and references therein), but a full assessment of internal structures has been hindered by interfering off-nadir echoes from spiral troughs and other variable topography prevalent on both caps. By assembling the SHARAD radargrams into a volume and applying a 3-D imaging process (migration) borrowed from seismic processing techniques, we enhance the signal-to-noise ratio while repositioning the echoes to their proper locations, thereby unraveling the interference. As part of the process, we correct ionospheric distortions and delays of the radar echoes (Campbell et al. 2014, IEEE GRSL 11 #3). Interfaces painstakingly mapped in radargrams (e.g., the basal-unit surface, a buried chasma) are clearly visible in the 3-D volume, and new features are revealed. Structures may now be mapped through trough-rich regions, including a widespread sequence that provides corroborative evidence of recent ice ages (Smith et al. 2015, LPSC XLVI #2574). Distinctive radar signatures associated with known, partially buried craters also occur elsewhere in the volume but without surface expression. Presumably, these are fully buried craters that may provide a new means to estimate the age of the deposits. Preliminary work for Planum Australe demonstrates that the 3-D processing currently underway will illuminate deep structures that are broadly obfuscated in 2-D radargrams by a shallow scatterer (Campbell et al. 2015, LPSC XLVI #2366).

  20. 3D Seismic Velocity Structure in the Rupture Area of the 2010 Maule Mw=8.8 Earthquake

    NASA Astrophysics Data System (ADS)

    Hicks, S. P.; Rietbrock, A.; Ryder, I. M.; Nippress, S.; Haberland, C. A.

    2011-12-01

    The 2010 Mw=8.8 Maule, Chile earthquake is one of the largest subduction zone earthquakes ever recorded. Up to now numerous co-seismic and some post-seismic slip models have been published based entirely on seismological, geodetic, or tsunami run-up heights, or combinations of these data. Most of these models use a simplified megathrust geometry derived mainly from global earthquake catalogues, and also simplified models of seismic parameters (e.g. shear modulus). By using arrival times for a vast number of aftershocks that have been recorded on a temporary seismic array, we present a new model for the slab geometry based on earthquake locations together with a new 3D seismic velocity model of the region, for both vp and vp/vs. We analyzed 3552 aftershocks that occurred between 18 March and 24 May 2011, recorded by the International Maule Aftershock Dataset (IMAD) seismic network. Event selection from a catalogue of automatically-determined events was based on 20 or more arrival times, from which at least 10 are S-wave observations. In total over 170,000 arrival times (~125,000 and 45,000 P and S wave arrival times respectively) are used for the tomographic reconstructions. Initially, events were relocated in a 2D velocity model based on a previously published model for the southern end of the rupture area (Haberland et al., 2009). Afterwards a staggered inversion scheme is implemented, starting with a 2D inversion followed by a coarse 3D and a subsequent fine 3D inversion. Based on our preliminary inversions we conclude that aftershock seismicity is mainly concentrated between 20 and 35 km depth along the subduction interface. A second band of seismicity between 40 and 50 km depth is also observed. Low seismic velocities and an increased vp/vs ratio characterize the marine forearc. The obtained velocity model will be discussed.

  1. 3D-seismic observations of Late Pleistocene glacial dynamics on the central West Greenland margin

    NASA Astrophysics Data System (ADS)

    Hofmann, Julia; Knutz, Paul; Cofaigh, Colm Ó.

    2016-04-01

    Fast-flowing ice streams and outlet glaciers exert a major control on glacial discharge from contemporary and palaeo ice sheets. Improving our understanding of the extent and dynamic behaviour of these palaeo-ice streams is therefore crucial for predictions of the response of ice sheets to present and future climate warming and the associated implications for global sea level. This poster presents results from two 3D-seismic surveys located on the shelf adjoining the Disko Bay trough-mouth fan (TMF), one of the largest glacial outlet systems in Greenland. Located at the seaward terminus of the c. 370 km long cross-shelf Disko Trough, the Disko Bay TMF was generated by highly efficient subglacial sediment delivery onto the continental slopes during repeated ice-stream advances. A variety of submarine glacial landform assemblages are recognised on the seabed reflecting past ice-stream activity presumably related to glacial-interglacial cycles. The 3D-seismic volumes cover the shallow banks located north and south of the Disko Trough. The focus of this study is the seabed and the uppermost stratigraphic interval associated with the Late Stage of TMF development, presumably covering the late Pleistocene (Hofmann et al., submitted). Seabed morphologies include multiple sets of ridges up to 20 m high that extend in NW-SE direction for c. 30 km, and cross-cutting curvilinear furrows with maximum lengths of c. 9 km and average depths of c. 4.5 m. Back-stepping, arcuate scarps facing NW define the shelf break on the northern survey, comprising average widths of c. 4.5 km and incision depths of c. 27.5 m. The large transverse ridge features on the southern survey are likely ice-marginal and are interpreted as terminal moraine ridges recording the existence of a shelf-edge terminating, grounded Late Weichselian ice sheet. The furrows, most prominent on the outer shelf adjoining the shallow banks and partly incising the moraine ridges, are interpreted as iceberg ploughmarks

  2. Quantitative analysis of accuracy of seismic wave-propagation codes in 3D random scattering media

    NASA Astrophysics Data System (ADS)

    Galis, Martin; Imperatori, Walter; Mai, P. Martin

    2013-04-01

    Several recent verification studies (e.g. Day et al., 2001; Bielak et al., 2010, Chaljub et al., 2010) have demonstrated the importance of assessing the accuracy of available numerical tools at low frequency in presence of large-scale features (basins, topography, etc.). The fast progress in high-performance computing, including efficient optimization of numerical codes on petascale supercomputers, has permitted the simulation of 3D seismic wave propagation at frequencies of engineering interest (up to 10Hz) in highly heterogeneous media (e.g. Hartzell et al, 2010; Imperatori and Mai, 2013). However, high frequency numerical simulations involving random scattering media, characterized by small-scale heterogeneities, are much more challenging for most numerical methods, and their verification may therefore be even more crucial than in the low-frequency case. Our goal is to quantitatively compare the accuracy and the behavior of three different numerical codes for seismic wave propagation in 3D random scattering media at high frequency. We deploy a point source with omega-squared spectrum, and focus on the near-source region, being of great interest in strong motion seismology. We use two codes based on finite-difference method (FD1 and FD2) and one code based on support-operator method (SO). Both FD1 and FD2 are 4-th order staggered-grid finite-difference codes (for FD1 see Olsen et al., 2009; for FD2 see Moczo et al., 2007). The FD1 and FD2 codes are characterized by slightly different medium representations, since FD1 uses point values of material parameters in each FD-cell, while FD2 uses the effective material parameters at each grid-point (Moczo et al., 2002). SO is 2-nd order support-operator method (Ely et al., 2008). We considered models with random velocity perturbations described by van Karman correlation function with different correlation lengths and different standard deviations. Our results show significant variability in both phase and amplitude as

  3. 3-D Structure of the Moho Interface beneath South Korea from Regional Seismic Observations

    NASA Astrophysics Data System (ADS)

    Gritto, R.; Siegel, J.; Chan, W. C.

    2007-12-01

    The current project is concerned with the collection and processing of seismic waveform data to perform 3-D tomographic inversions and produce high-resolution 3-D crustal P- and S-wave velocity models for the South Korean peninsula. At present, we have analyzed and archived Korean Meteorological Administration (KMA) waveform data from 2001 through 2006 and mapped of the Moho discontinuity below South Korea. Phase arrival information from both, velocity and accelerometer sensors were collected. The analysis included 226 events throughout the region producing a total of 6,275 phase picks including Pg, Pn, Sg/Lg, and Sn phases. A total of 3,550 P-wave and 2,725 S-wave phases were identified. Using the combination of all available velocity and accelerometer data it was possible to estimate depth locations for 198 KMA events. The hypocenters were subsequently used to derive travel-time distance curves to appraise the quality of the travel-time picks. Static corrections were calculated for each seismic station within the KMA network to remove the effects of local inhomogeneities in the vicinity of each station. After applying static corrections to the observed travel-times, refracted P-wave phases along the Moho boundary were selected from the dataset to estimate the depth and topography of the Moho discontinuity beneath South Korea. In total, 526 Pn phases were collected from the KMA data with hypocentral distances from 130 km to over 650 km. The resulting Moho topography reveals a slightly undulating interface with a large-scale dip from north (31 km) to south (38 km) and a depth range from 32 km in the east to 39 km in the south-west. On a smaller scale, a more pronounced depression is evident in the south- central part of the mapped area, which opens to the south. The presented results are corroborated by other studies which mapped the Moho interface using surface-wave dispersion and receiver-function analysis. The present study is complementary to these earlier

  4. Comparative velocity structure of active Hawaiian volcanoes from 3-D onshore-offshore seismic tomography

    USGS Publications Warehouse

    Park, J.; Morgan, J.K.; Zelt, C.A.; Okubo, P.G.; Peters, L.; Benesh, N.

    2007-01-01

    We present a 3-D P-wave velocity model of the combined subaerial and submarine portions of the southeastern part of the Island of Hawaii, based on first-arrival seismic tomography of marine airgun shots recorded by the onland seismic network. Our model shows that high-velocity materials (6.5-7.0??km/s) lie beneath Kilauea's summit, Koae fault zone, and the upper Southwest Rift Zone (SWRZ) and upper and middle East Rift Zone (ERZ), indicative of magma cumulates within the volcanic edifice. A separate high-velocity body of 6.5-6.9??km/s within Kilauea's lower ERZ and upper Puna Ridge suggests a distinct body of magma cumulates, possibly connected to the summit magma cumulates at depth. The two cumulate bodies within Kilauea's ERZ may have undergone separate ductile flow seaward, influencing the submarine morphology of Kilauea's south flank. Low velocities (5.0-6.3??km/s) seaward of Kilauea's Hilina fault zone, and along Mauna Loa's seaward facing Kao'iki fault zone, are attributed to thick piles of volcaniclastic sediments deposited on the submarine flanks. Loihi seamount shows high-velocity anomalies beneath the summit and along the rift zones, similar to the interpreted magma cumulates below Mauna Loa and Kilauea volcanoes, and a low-velocity anomaly beneath the oceanic crust, probably indicative of melt within the upper mantle. Around Kilauea's submarine flank, a high-velocity anomaly beneath the outer bench suggests the presence of an ancient seamount that may obstruct outward spreading of the flank. Mauna Loa's southeast flank is also marked by a large, anomalously high-velocity feature (7.0-7.4??km/s), interpreted to define an inactive, buried volcanic rift zone, which might provide a new explanation for the westward migration of Mauna Loa's current SWRZ and the growth of Kilauea's SWRZ. ?? 2007 Elsevier B.V. All rights reserved.

  5. 3-D Crustal Velocity Structure Across the Vrancea Zone in Romania, Derived From Seismic Data

    NASA Astrophysics Data System (ADS)

    Landes, M.; Hauser, F.; Popa, M.

    2002-12-01

    The Vrancea zone in the south-eastern Carpathians is one of the most active seismic zones in Europe. In order to study the crustal and upper-mantle structure in this region, two seismic refraction/wide-angle reflection experiments were carried out in 1999 and 2001. The 1999 campaign comprised a 320 km long N-S profile and a 80 km long transverse profile (E-W). All shots were recorded simultaneously on both profiles. The profile conducted in 2001 extended in E-W direction from the Hungarian border across the Vrancea zone to the Black Sea. We present an application of a 3-D refraction and reflection tomography algorithm (Hole 1992, 1995), elaborating the crustal velocity and interface structure within a 115 x 235 km wide region around the Vrancea zone. In order to enhance the model resolution, first arrival data from local earthquakes of the CALIXTO-99 teleseismic project were also included. The results indicate a high-velocity structure beneath the northern part of the Vrancea zone extending from shallow levels to depths of about 11 km. This structure may be related to the Trotus and Capidava-Ovidiu faults, which converge to the north of it. The high-velocity region is surrounded by the lower velocity Focsani and Brasov basins. The sedimentary succession beneath the southern part of the model extends to 18 km depth, while in the north sediment thickness varies between 10 and 15 km. Further results of the interface modelling of prominent reflections show that the mid-crustal and Moho interfaces shallow northwards from 30 km to 22 km and from 42 km to 38 km, respectively. This correlates well with previous results of Hauser et al. (2001).

  6. 3D simulation of seismic wave propagation around a tunnel using the spectral element method

    NASA Astrophysics Data System (ADS)

    Lambrecht, L.; Friederich, W.

    2010-05-01

    We model seismic wave propagation in the environment of a tunnel for later application to reconnaissance. Elastic wave propagation can be simulated by different numerical techniques such as finite differences and pseudospectral methods. Their disadvantage is the lack of accuracy on free surfaces, numerical dispersion and inflexibility of the mesh. Here we use the software package SPECFEM3D_SESAME in an svn development version, which is based on the spectral element method (SEM) and can handle complex mesh geometries. A weak form of the elastic wave equation leads to a linear system of equations with a diagonal mass matrix, where the free surface boundary of the tunnel can be treated under realistic conditions and can be effectively implemented in parallel. We have designed a 3D external mesh including a tunnel and realistic features such as layers and holes to simulate elastic wave propagation in the zone around the tunnel. The source is acting at the tunnel surface so that we excite Rayleigh waves which propagate to the front face of the tunnel. A conversion takes place and a high amplitude S-wave is radiated in the direction of the tunnel axis. Reflections from perturbations in front of the tunnel can be measured by receivers implemented on the tunnel face. For a shallow tunnel the land surface has high influence on the wave propagation. By implementing additional receivers at this surface we intent to improve the prediction. It shows that the SEM is very capable to handle the complex geometry of the model and especially incorporates the free surfaces of the model.

  7. Assessing 3D tunnel position in ACL reconstruction using a novel single image 3D-2D registration

    NASA Astrophysics Data System (ADS)

    Kang, X.; Yau, W. P.; Otake, Y.; Cheung, P. Y. S.; Hu, Y.; Taylor, R. H.

    2012-02-01

    The routinely used procedure for evaluating tunnel positions following anterior cruciate ligament (ACL) reconstructions based on standard X-ray images is known to pose difficulties in terms of obtaining accurate measures, especially in providing three-dimensional tunnel positions. This is largely due to the variability in individual knee joint pose relative to X-ray plates. Accurate results were reported using postoperative CT. However, its extensive usage in clinical routine is hampered by its major requirement of having CT scans of individual patients, which is not available for most ACL reconstructions. These difficulties are addressed through the proposed method, which aligns a knee model to X-ray images using our novel single-image 3D-2D registration method and then estimates the 3D tunnel position. In the proposed method, the alignment is achieved by using a novel contour-based 3D-2D registration method wherein image contours are treated as a set of oriented points. However, instead of using some form of orientation weighting function and multiplying it with a distance function, we formulate the 3D-2D registration as a probability density estimation using a mixture of von Mises-Fisher-Gaussian (vMFG) distributions and solve it through an expectation maximization (EM) algorithm. Compared with the ground-truth established from postoperative CT, our registration method in an experiment using a plastic phantom showed accurate results with errors of (-0.43°+/-1.19°, 0.45°+/-2.17°, 0.23°+/-1.05°) and (0.03+/-0.55, -0.03+/-0.54, -2.73+/-1.64) mm. As for the entry point of the ACL tunnel, one of the key measurements, it was obtained with high accuracy of 0.53+/-0.30 mm distance errors.

  8. 3-D Adaptive Sparsity Based Image Compression With Applications to Optical Coherence Tomography.

    PubMed

    Fang, Leyuan; Li, Shutao; Kang, Xudong; Izatt, Joseph A; Farsiu, Sina

    2015-06-01

    We present a novel general-purpose compression method for tomographic images, termed 3D adaptive sparse representation based compression (3D-ASRC). In this paper, we focus on applications of 3D-ASRC for the compression of ophthalmic 3D optical coherence tomography (OCT) images. The 3D-ASRC algorithm exploits correlations among adjacent OCT images to improve compression performance, yet is sensitive to preserving their differences. Due to the inherent denoising mechanism of the sparsity based 3D-ASRC, the quality of the compressed images are often better than the raw images they are based on. Experiments on clinical-grade retinal OCT images demonstrate the superiority of the proposed 3D-ASRC over other well-known compression methods. PMID:25561591

  9. 3-D Adaptive Sparsity Based Image Compression with Applications to Optical Coherence Tomography

    PubMed Central

    Fang, Leyuan; Li, Shutao; Kang, Xudong; Izatt, Joseph A.; Farsiu, Sina

    2015-01-01

    We present a novel general-purpose compression method for tomographic images, termed 3D adaptive sparse representation based compression (3D-ASRC). In this paper, we focus on applications of 3D-ASRC for the compression of ophthalmic 3D optical coherence tomography (OCT) images. The 3D-ASRC algorithm exploits correlations among adjacent OCT images to improve compression performance, yet is sensitive to preserving their differences. Due to the inherent denoising mechanism of the sparsity based 3D-ASRC, the quality of the compressed images are often better than the raw images they are based on. Experiments on clinical-grade retinal OCT images demonstrate the superiority of the proposed 3D-ASRC over other well-known compression methods. PMID:25561591

  10. 3-D Imaging Systems for Agricultural Applications-A Review.

    PubMed

    Vázquez-Arellano, Manuel; Griepentrog, Hans W; Reiser, David; Paraforos, Dimitris S

    2016-01-01

    Efficiency increase of resources through automation of agriculture requires more information about the production process, as well as process and machinery status. Sensors are necessary for monitoring the status and condition of production by recognizing the surrounding structures such as objects, field structures, natural or artificial markers, and obstacles. Currently, three dimensional (3-D) sensors are economically affordable and technologically advanced to a great extent, so a breakthrough is already possible if enough research projects are commercialized. The aim of this review paper is to investigate the state-of-the-art of 3-D vision systems in agriculture, and the role and value that only 3-D data can have to provide information about environmental structures based on the recent progress in optical 3-D sensors. The structure of this research consists of an overview of the different optical 3-D vision techniques, based on the basic principles. Afterwards, their application in agriculture are reviewed. The main focus lays on vehicle navigation, and crop and animal husbandry. The depth dimension brought by 3-D sensors provides key information that greatly facilitates the implementation of automation and robotics in agriculture. PMID:27136560

  11. 3-D Imaging Systems for Agricultural Applications—A Review

    PubMed Central

    Vázquez-Arellano, Manuel; Griepentrog, Hans W.; Reiser, David; Paraforos, Dimitris S.

    2016-01-01

    Efficiency increase of resources through automation of agriculture requires more information about the production process, as well as process and machinery status. Sensors are necessary for monitoring the status and condition of production by recognizing the surrounding structures such as objects, field structures, natural or artificial markers, and obstacles. Currently, three dimensional (3-D) sensors are economically affordable and technologically advanced to a great extent, so a breakthrough is already possible if enough research projects are commercialized. The aim of this review paper is to investigate the state-of-the-art of 3-D vision systems in agriculture, and the role and value that only 3-D data can have to provide information about environmental structures based on the recent progress in optical 3-D sensors. The structure of this research consists of an overview of the different optical 3-D vision techniques, based on the basic principles. Afterwards, their application in agriculture are reviewed. The main focus lays on vehicle navigation, and crop and animal husbandry. The depth dimension brought by 3-D sensors provides key information that greatly facilitates the implementation of automation and robotics in agriculture. PMID:27136560

  12. Coupling the 3D hydro-morphodynamic model Telemac-3D-sisyphe and seismic measurements to estimate bedload transport rates in a small gravel-bed river.

    NASA Astrophysics Data System (ADS)

    Hostache, Renaud; Krein, Andreas; Barrière, Julien

    2014-05-01

    Coupling the 3D hydro-morphodynamic model Telemac-3D-sisyphe and seismic measurements to estimate bedload transport rates in a small gravel-bed river. Renaud Hostache, Andreas Krein, Julien Barrière During flood events, amounts of river bed material are transported via bedload. This causes problems, like the silting of reservoirs or the disturbance of biological habitats. Some current bedload measuring techniques have limited possibilities for studies in high temporal resolutions. Optical systems are usually not applicable because of high turbidity due to concentrated suspended sediment transported. Sediment traps or bedload samplers yield only summative information on bedload transport with low temporal resolution. An alternative bedload measuring technique is the use of seismological systems installed next to the rivers. The potential advantages are observations in real time and under undisturbed conditions. The study area is a 120 m long reach of River Colpach (21.5 km2), a small gravel bed river in Northern Luxembourg. A combined approach of hydro-climatological observations, hydraulic measurements, sediment sampling, and seismological measurements is used in order to investigate bedload transport phenomena. Information derived from seismic measurements and results from a 3-dimensional hydro-morphodynamic model are exemplarily discussed for a November 2013 flood event. The 3-dimensional hydro-morphodynamic model is based on the Telemac hydroinformatic system. This allows for dynamically coupling a 3D hydrodynamic model (Telemac-3D) and a morphodynamic model (Sisyphe). The coupling is dynamic as these models exchange their information during simulations. This is a main advantage as it allows for taking into account the effects of the morphologic changes of the riverbed on the water hydrodynamic and the bedload processes. The coupled model has been calibrated using time series of gauged water depths and time series of bed material collected sequentially (after

  13. Dense 3d Point Cloud Generation from Uav Images from Image Matching and Global Optimazation

    NASA Astrophysics Data System (ADS)

    Rhee, S.; Kim, T.

    2016-06-01

    3D spatial information from unmanned aerial vehicles (UAV) images is usually provided in the form of 3D point clouds. For various UAV applications, it is important to generate dense 3D point clouds automatically from over the entire extent of UAV images. In this paper, we aim to apply image matching for generation of local point clouds over a pair or group of images and global optimization to combine local point clouds over the whole region of interest. We tried to apply two types of image matching, an object space-based matching technique and an image space-based matching technique, and to compare the performance of the two techniques. The object space-based matching used here sets a list of candidate height values for a fixed horizontal position in the object space. For each height, its corresponding image point is calculated and similarity is measured by grey-level correlation. The image space-based matching used here is a modified relaxation matching. We devised a global optimization scheme for finding optimal pairs (or groups) to apply image matching, defining local match region in image- or object- space, and merging local point clouds into a global one. For optimal pair selection, tiepoints among images were extracted and stereo coverage network was defined by forming a maximum spanning tree using the tiepoints. From experiments, we confirmed that through image matching and global optimization, 3D point clouds were generated successfully. However, results also revealed some limitations. In case of image-based matching results, we observed some blanks in 3D point clouds. In case of object space-based matching results, we observed more blunders than image-based matching ones and noisy local height variations. We suspect these might be due to inaccurate orientation parameters. The work in this paper is still ongoing. We will further test our approach with more precise orientation parameters.

  14. Segmented images and 3D images for studying the anatomical structures in MRIs

    NASA Astrophysics Data System (ADS)

    Lee, Yong Sook; Chung, Min Suk; Cho, Jae Hyun

    2004-05-01

    For identifying the pathological findings in MRIs, the anatomical structures in MRIs should be identified in advance. For studying the anatomical structures in MRIs, an education al tool that includes the horizontal, coronal, sagittal MRIs of entire body, corresponding segmented images, 3D images, and browsing software is necessary. Such an educational tool, however, is hard to obtain. Therefore, in this research, such an educational tool which helps medical students and doctors study the anatomical structures in MRIs was made as follows. A healthy, young Korean male adult with standard body shape was selected. Six hundred thirteen horizontal MRIs of the entire body were scanned and inputted to the personal computer. Sixty anatomical structures in the horizontal MRIs were segmented to make horizontal segmented images. Coronal, sagittal MRIs and coronal, sagittal segmented images were made. 3D images of anatomical structures in the segmented images were reconstructed by surface rendering method. Browsing software of the MRIs, segmented images, and 3D images was composed. This educational tool that includes horizontal, coronal, sagittal MRIs of entire body, corresponding segmented images, 3D images, and browsing software is expected to help medical students and doctors study anatomical structures in MRIs.

  15. 3-D Reconstruction From 2-D Radiographic Images and Its Application to Clinical Veterinary Medicine

    NASA Astrophysics Data System (ADS)

    Hamamoto, Kazuhiko; Sato, Motoyoshi

    3D imaging technique is very important and indispensable in diagnosis. The main stream of the technique is one in which 3D image is reconstructed from a set of slice images, such as X-ray CT and MRI. However, these systems require large space and high costs. On the other hand, a low cost and small size 3D imaging system is needed in clinical veterinary medicine, for example, in the case of diagnosis in X-ray car or pasture area. We propose a novel 3D imaging technique using 2-D X-ray radiographic images. This system can be realized by cheaper system than X-ray CT and enables to get 3D image in X-ray car or portable X-ray equipment. In this paper, a 3D visualization technique from 2-D radiographic images is proposed and several reconstructions are shown. These reconstructions are evaluated by veterinarians.

  16. Assessment of rhinoplasty techniques by overlay of before-and-after 3D images.

    PubMed

    Toriumi, Dean M; Dixon, Tatiana K

    2011-11-01

    This article describes the equipment and software used to create facial 3D imaging and discusses the validation and reliability of the objective assessments done using this equipment. By overlaying preoperative and postoperative 3D images, it is possible to assess the surgical changes in 3D. Methods are described to assess the 3D changes from the rhinoplasty techniques of nasal dorsal augmentation, increasing tip projection, narrowing the nose, and nasal lengthening. PMID:22004862

  17. 3D Seismic Reflection Data: Has the Geological Hubble Retained Its Focus?

    NASA Astrophysics Data System (ADS)

    Jackson, Christopher

    2016-04-01

    In their seminal paper in 2002, Joe Cartwright and Mads Huuse referred to 3D seismic reflection data as the 'Geological Hubble', illustrating how these data had the potential to revolutionise our understanding of the genesis and evolution of sedimentary basins. 14 years on, I will here outline just some of the key recent advances made in our understanding of basin structure and stratigraphy, focusing on: (i) the intrusion and extrusion of igneous rocks; (ii) salt tectonics, with particular emphasis on intrasalt structure and the kinematics and mechanics of diapirism; (iii) the geometry and growth of normal faults; and (iv) the structure and emplacement of mass-transport complexes (MTCs). I will stress that future advances at least partly relies on hydrocarbon exploration companies and government agencies continuing to make their data freely available via easy-to-access data portals. I will issue a clarion call to academics, stressing that 'geodynamicists', sedimentologists, structural geologists and geomorphologists, amongst others, can benefit from utilising what I believe are currently an underused data type.

  18. Effect of 3-D viscoelastic structure on post-seismic relaxation from the 2004 M = 9.2 Sumatra earthquake

    USGS Publications Warehouse

    Pollitz, F.; Banerjee, P.; Grijalva, K.; Nagarajan, B.; Burgmann, R.

    2008-01-01

    The 2004 M=9.2 Sumatra-Andaman earthquake profoundly altered the state of stress in a large volume surrounding the ???1400 km long rupture. Induced mantle flow fields and coupled surface deformation are sensitive to the 3-D rheology structure. To predict the post-seismic motions from this earthquake, relaxation of a 3-D spherical viscoelastic earth model is simulated using the theory of coupled normal modes. The quasi-static deformation basis set and solution on the 3-D model is constructed using: a spherically stratified viscoelastic earth model with a linear stress-strain relation; an aspherical perturbation in viscoelastic structure; a 'static'mode basis set consisting of Earth's spheroidal and toroidal free oscillations; a "viscoelastic" mode basis set; and interaction kernels that describe the coupling among viscoelastic and static modes. Application to the 2004 Sumatra-Andaman earthquake illustrates the profound modification of the post-seismic flow field at depth by a slab structure and similarly large effects on the near-field post-seismic deformation field at Earth's surface. Comparison with post-seismic GPS observations illustrates the extent to which viscoelastic relaxation contributes to the regional post-seismic deformation. ?? Journal compilation ?? 2008 RAS.

  19. Development and Calibration of New 3-D Vector VSP Imaging Technology: Vinton Salt Dome, LA

    SciTech Connect

    Kurt J. Marfurt; Hua-Wei Zhou; E. Charlotte Sullivan

    2004-09-01

    Vinton salt dome is located in Southwestern Louisiana, in Calcasieu Parish. Tectonically, the piercement dome is within the salt dome minibasin province. The field has been in production since 1901, with most of the production coming from Miocene and Oligocene sands. The goal of our project was to develop and calibrate new processing and interpretation technology to fully exploit the information available from a simultaneous 3-D surface seismic survey and 3-C, 3-D vertical seismic profile (VSP) survey over the dome. More specifically the goal was to better image salt dome flanks and small, reservoir-compartmentalizing faults. This new technology has application to mature salt-related fields across the Gulf Coast. The primary focus of our effort was to develop, apply, and assess the limitations of new 3-C, 3-D wavefield separation and imaging technology that could be used to image aliased, limited-aperture, vector VSP data. Through 2-D and 3-D full elastic modeling, we verified that salt flank reflections exist in the horizontally-traveling portion of the wavefield rather than up- and down-going portions of the wavefield, thereby explaining why many commercial VSP processing flow failed. Since the P-wave reflections from the salt flank are measured primarily on the horizontal components while P-wave reflections from deeper sedimentary horizons are measured primarily on the vertical component, a true vector VSP analysis was needed. We developed an antialiased discrete Radon transform filter to accurately model P- and S-wave data components measured by the vector VSP. On-the-fly polarization filtering embedded in our Kirchhoff imaging algorithm was effective in separating PP from PS wave images. By the novel application of semblance-weighted filters, we were able to suppress many of the migration artifacts associated with low fold, sparse VSP acquisition geometries. To provide a better velocity/depth model, we applied 3-D prestack depth migration to the surface data

  20. High-resolution seismic array imaging based on numerical seismic wave simulations

    NASA Astrophysics Data System (ADS)

    Liu, Q.; Tong, P.; Chen, C.

    2012-12-01

    Adjoint tomography, i.e., seismic tomography based on full numerical simulations and adjoint methods, is a powerful tool for high-resolution imaging in heterogeneous media. It resolves large velocity contrasts through the use of 3D initial models and exploits more quantitative information from observed seismograms. However, for regions with limited local seismicity, seismic imaging relies more on teleseismic records. In particular coda and converted waves of main teleseismic arrivals used in scattering imaging are vital in resolving subsurface interfaces and velocity anomalies beneath seismic arrays. It remains numerically challenging to accurately and efficiently simulate the full propagation of seismic waves at the frequencies relevant to scattering imaging. In this work, to simulate the propagation of teleseismic planes waves into localized heterogeneous structures, we apply a hybrid method that interacts a spectral-element solver within the domain with a semi-analytical solution for 1D background medium at the absorbing boundaries. This technique will be implemented in both SPECFEM2D and SPECFEM3D packages and make it possible to invert both regional and teleseismic recordings in the framework of adjoint tomography. Synthetic tests will be performed to show the feasibility of high-resolution seismic array imaging of coda and converted waves based on adjoint techniques.

  1. Implementation of wireless 3D stereo image capture system and 3D exaggeration algorithm for the region of interest

    NASA Astrophysics Data System (ADS)

    Ham, Woonchul; Song, Chulgyu; Lee, Kangsan; Badarch, Luubaatar

    2015-05-01

    In this paper, we introduce the mobile embedded system implemented for capturing stereo image based on two CMOS camera module. We use WinCE as an operating system and capture the stereo image by using device driver for CMOS camera interface and Direct Draw API functions. We aslo comments on the GPU hardware and CUDA programming for implementation of 3D exaggeraion algorithm for ROI by adjusting and synthesizing the disparity value of ROI (region of interest) in real time. We comment on the pattern of aperture for deblurring of CMOS camera module based on the Kirchhoff diffraction formula and clarify the reason why we can get more sharp and clear image by blocking some portion of aperture or geometric sampling. Synthesized stereo image is real time monitored on the shutter glass type three-dimensional LCD monitor and disparity values of each segment are analyzed to prove the validness of emphasizing effect of ROI.

  2. Evolution of 3D surface imaging systems in facial plastic surgery.

    PubMed

    Tzou, Chieh-Han John; Frey, Manfred

    2011-11-01

    Recent advancements in computer technologies have propelled the development of 3D imaging systems. 3D surface-imaging is taking surgeons to a new level of communication with patients; moreover, it provides quick and standardized ima