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Journal articles on the topic 'Wide Angle Reflection/Refraction'

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Published: 11 March 2023

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1

Rendleman, C. A., and F. K. Levin. "Reflection maxima for reflections from single interfaces." GEOPHYSICS 53, no. 2 (February 1988): 271–75. http://dx.doi.org/10.1190/1.1442462.

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At a workshop on refraction and wide‐angle reflections, Hilterman (1985) pointed out that, in contrast to the plane‐wave case, when there is a point source, a P-wave reflected from a plane interface attains its maximum amplitude at an offset greater than that corresponding to the critical angle (Figure 1). The same conclusion had been drawn earlier by Červený (1967). However, neither Červený’s results, which were based on very complicated mathematical expressions derived by Brekhovskikh (1960), nor Hilterman’s computer‐generated data shed light on the physics implied by the shifted maximum.

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2

Filatova, Elena, and Andrey Sokolov. "Effect of reflection and refraction on NEXAFS spectra measured in TEY mode." Journal of Synchrotron Radiation 25, no. 1 (January 1, 2018): 232–40. http://dx.doi.org/10.1107/s1600577517016253.

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The evolution of near-edge X-ray absorption fine structure in the vicinity of theK-absorption edge of oxygen for HfO2over a wide range of incidence angles is analyzed by simultaneous implementation of the total-electron-yield (TEY) method and X-ray reflection spectroscopy. It is established that the effect of refraction on the TEY spectrum is greater than that of reflection and extends into the angular region up to angles 2θc. Within angles that are less than the critical angle, both the reflection and refraction strongly distort the shape of the TEY spectrum. Limitations of the technique for the calculation of optical constants from the reflection spectra using the Kramers–Kronig relation in the limited energy region in the vicinity of thresholds are discussed in detail.

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3

Mereu, R. F. "The complexity of the crust from refraction/wide-angle reflection data." Pure and Applied Geophysics PAGEOPH 132, no. 1-2 (1990): 269–88. http://dx.doi.org/10.1007/bf00874366.

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4

Mereu, R. F. "The complexity of the crust and Moho under the southeastern Superior and Grenville provinces of the Canadian Shield from seismic refraction - wide-angle reflection data." Canadian Journal of Earth Sciences 37, no. 2-3 (April 2, 2000): 439–58. http://dx.doi.org/10.1139/e99-122.

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The major features of the individual velocity models, Poisson's ratio values, and crustal complexity derived from the interpretation of seismic data sets from four long-range seismic refraction - wide-angle reflection experiments are summarized. The experiments were conducted from 1982-92 in the southeastern portion of the Canadian Shield. In the conventional analysis of seismic refraction - wide-angle reflection data, only the onset times and amplitudes of the major arrival phases are used to derive seismic velocity models of the region under study. These models are over smoothed, have a number of intermediate discontinuities, are unable to explain the Pg coda, and bear very little resemblance to the models derived from the analysis of near-vertical seismic reflection data. In this paper some of the differences between seismic models derived from near-vertical reflection analysis and those from refraction analysis are reconciled from an analysis of the wide-angle reflection fields of the crustal coda waves that follow the first arrivals. This was done using a migration technique that to a first approximation maps the amplitudes of the record sections into a two-dimensional (2-D) complexity section. These new sections show significant lateral variations in crustal and Moho reflectivity and may be used to complement the 2-D velocity anomaly sections and near-vertical reflection sections. The method was based on a numerical study that showed that the coda can be explained with a class of complex heterogeneous models in which sets of small-scale, high-contrast sloping seismic reflectors are "embedded" in a uniform seismic velocity gradient field.

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5

Luetgert, James, and Carol E. Mann. "Avalon terrane in eastern coastal Maine: Seismic refraction-wide-angle reflection data." Geology 18, no. 9 (1990): 878. http://dx.doi.org/10.1130/0091-7613(1990)018<0878:atiecm>2.3.co;2.

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6

Pawlik, G., K. Tarnowski, W. Walasik, A. C. Mitus, and I. C. Khoo. "Liquid crystal hyperbolic metamaterial for wide-angle negative–positive refraction and reflection." Optics Letters 39, no. 7 (March 19, 2014): 1744. http://dx.doi.org/10.1364/ol.39.001744.

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7

Majdański, M. "The uncertainty in layered models from wide-angle seismic data." GEOPHYSICS 78, no. 3 (May 1, 2013): WB31—WB36. http://dx.doi.org/10.1190/geo2012-0280.1.

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The analytical method of estimating the uncertainty in layered models is addressed to models obtained using a layer-stripping modeling strategy or forward modeling. It is based on a simple principle of small error propagation. There are two variants of the method: a simplified one that includes refraction and vertical reflections and one that also includes wide-angle reflections. Both give a quantitative estimation for the existing models. To allow for a simple analytical estimation, refracted waves are described using a head-wave approximation in constant velocity layers; wide angle reflection paths are also simplified. In the case of trial and error forward modeling, this method can help determine how well the used parameterization is reflected in the data and avoid over-fitting the structures. This is especially important because the forward modeling is very subjective and there is no method to assess the parameterization without generating alternative models. For inversion problems using the layer-stripping method, the analysis allows for a correct propagation of errors and will help to evaluate the effect of including a priori information with known uncertainty. As a result, the layer-stripping modeling strategy is worse than simultaneous inversion for layered models because it gives larger uncertainties.

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8

Németh, Balázs, Ron M. Clowes, and Zoltan Hajnal. "Lithospheric structure of the Trans-Hudson Orogen from seismic refraction - wide-angle reflection studies." Canadian Journal of Earth Sciences 42, no. 4 (April 1, 2005): 435–56. http://dx.doi.org/10.1139/e05-032.

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The Trans-Hudson Orogen (THO) is the world's largest Paleoproterozoic orogenic belt. Data from three refraction profiles are used to investigate its lithospheric structure in Saskatchewan and Manitoba. R1 crosses the orogen from the Hearne craton on the west to the Superior craton on the east; R2 and R3 are along the orogen. P-wave velocity structural models are generated using a ray-based technique. On line R1, higher crustal velocities in its eastern part coincide with rocks of the Flin Flon Namew gneiss complex. Depth to Moho is in the 4045 km range and equates to that from the reflection data, including a small crustal root below the Sask minicontinent. Along lines R2 and R3, depth to Moho varies from about 40 km up to 55 km at the north end of R2 and south end of R3. In general, variations in crustal velocity and depth to Moho do not correlate with the location and extent of geological domains; they appear to reflect the complex deformation and metamorphic history of the crustal rocks. Mantle velocities are high, ~8.2 km/s. However a limited area shows prominent velocity anisotropy, with values of 8.6 km/s along R2 and R3 and 8.1 km/s along R1. We speculate that the observed anisotropy represents an ~100-km-wide mantle suture zone resulting from the collision of Archean plates. The suture zone accommodated limited extensional deformation, associated with a counterclockwise rotation of the Superior plate, to generate the anisotropy. In this model, the lithospheric mantle of the THO internal domains and Sask craton are detached.

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9

Roberts, D. G., A. Ginzberg, K. Nunn, and R. McQuillin. "The structure of the Rockall Trough from seismic refraction and wide-angle reflection measurements." Nature 332, no. 6165 (April 1988): 632–35. http://dx.doi.org/10.1038/332632a0.

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10

Hole, J. A., R. M. Clowes, and R. M. Ellis. "Interpretation of three-dimensional seismic refraction data from western Hecate Strait, British Columbia: structure of the crust." Canadian Journal of Earth Sciences 30, no. 7 (July 1, 1993): 1440–52. http://dx.doi.org/10.1139/e93-124.

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As part of a multidisciplinary investigation of the structure and tectonics of the Queen Charlotte Basin and underlying crust, deep multichannel seismic reflection and coincident crustal refraction data were collected in 1988. Energy from the reflection air-gun array source was recorded at land sites at offsets appropriate to record crustal refraction and wide-angle reflection data. Refraction data recorded in a broadside geometry provide good three-dimensional coverage of western Hecate Strait. These data are modelled using tomographic inversion techniques to determine the three-dimensional velocity structure of the crust in this region. The one-dimensional average velocity increases rapidly with depth to 6.5 km/s at 7 km depth. Velocities from 7 to at least 12 km depth remain approximately constant and are associated with rocks of the Wrangellia terrane. Significant lateral velocity variations, including large differences in near-surface velocities attributable to surface features, relatively low velocities representing interbedded Tertiary sediments and volcanics, and a deep high-velocity anomaly that may represent the root of an igneous intrusion, are mapped. Wide-angle reflections from the Moho are used to determine the thickness of the crust. The Moho is at 29 km depth beneath the east coast of the Queen Charlotte Islands. This is deeper than the Moho observed below Queen Charlotte Sound and as deep as, or deeper than, that below Hecate Strait. Crustal thinning during Tertiary extension was thus greatest beneath the surface expression of the Queen Charlotte Basin, leaving the crust under the islands considerably thicker than under the basin. In an alternate or additional explanation, compression at the continental margin during the last 4 Ma may have been taken up by thickening or underplating of the continental crust beneath the islands. If the Pacific plate is subducting beneath the islands, the Moho observations constrain the slab to dip greater than 20–26°.

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11

Bohidar, Rabi N., and John F. Hermance. "The GPR refraction method." GEOPHYSICS 67, no. 5 (September 2002): 1474–85. http://dx.doi.org/10.1190/1.1512792.

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Refracted phases have been a recognized feature in wide‐angle common midpoint (CMP) and common shotpoint (CSP) ground‐penetrating radar (GPR) surveys for many years, but historically their use has been limited and overshadowed by conventional reflection profiling techniques. In truth, the GPR refraction method holds great promise, as we show using four field examples from three sites in the northeastern United States. Typical refractors are shallow bedrock or coarse‐grained unconsolidated sediments (where the dielectric constant K ≈ 6–7) beneath partially saturated fine‐grained sand or silt (K ≈ 15–16). Under appropriate conditions, refracted phases can be detected readily at transmitter–receiver (Tx–Rx) offsets of >15 m and from depths of >2 m. Adapting procedures from refraction seismology, we interpret GPR data from reversed CSP soundings using dipping planar interface models and delay time analyses. Results from the two approaches are quite consistent, further corroborated at one of the sites by a GPR reflection profile and directly verified by a series of hammer‐driven probes. In addition to refractions from higher velocity layers in the subsurface, the air refracted phase (the ubiquitous phase refracted from the air–earth interface) can provide important constraints on interpreting the subsurface—particularly useful when attempting to resolve a shallow interface (depth ≤ 0.5 m) whose GPR signature might be masked by interacting phases at early traveltime and small transmitter–receiver offsets. Finally, a cautionary note for interpreting conventional reflection profile data when delineating a higher velocity interface at a depth that might be on the order of the antenna separation or less. Since the refracted phase arrives earlier than the reflected phase for Tx–Rx offsets beyond the critical distance, in certain cases the first break on a reflection radargram may actually be a refraction. CMP or CSP soundings in support of conventional GPR profiles can resolve such concerns.

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12

Oueity, Jounada, and Ron M. Clowes. "Paleoproterozoic subduction in northwestern Canada from near-vertical and wide-angle seismic reflection data." Canadian Journal of Earth Sciences 47, no. 1 (January 2010): 35–52. http://dx.doi.org/10.1139/e09-073.

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Near-vertical incidence and refraction – wide-angle reflection seismic data, recorded as part of Lithoprobe studies in the Paleoproterozoic–Archean domains of Canada’s Northwest Territories, show remarkable reflections from within the upper mantle. A parallel pair of reflectors imaged by the near-vertical data can be traced from Moho levels (∼33 km) down to ∼70 km depth. In a previous study, the reflectors were interpreted as the top and bottom of an ∼1.8 Ga subducted oceanic crust beneath the Hottah terrane. Further inboard, where the seismic line changes its direction from east–west to nearly north–south, another pair of reflectors extends subhorizontally for about 100 km at ∼70 km depth before dipping downward. The subhorizontal reflectors were not correlated with the dipping slab; instead they were interpreted as a separate feature. However, they roughly coincide with a horizontal interface modeled from wide-angle data by an earlier study. Considering the crooked line acquisition geometry, we re-examined both near-vertical incidence and wide-angle reflection data using 2-dimensional (2-D) and 3-D forward and inverse modeling algorithms. Our results demonstrate that the subhorizontal reflectors are the continuation of the relict subducted slab, which now extends laterally for 300 km. Its base is the source of the wide-angle data. The apparent flattening for the near-vertical data is most likely an artifact of projecting a 3-D geometry onto a 2-D cross section. The shallowly subducted slab probably contributed to the thickening and stabilization of the subcrustal lithosphere below the Wopmay orogen.

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13

Zelt, B. C., R. M. Ellis, R. M. Clowes, E. R. Kanasewich, I. Asudeh, J. H. Luetgert, Z. Hajnal, A. Ikami, G. D. Spence, and R. D. Hyndman. "Crust and upper mantle velocity structure of the Intermontane belt, southern Canadian Cordillera." Canadian Journal of Earth Sciences 29, no. 7 (July 1, 1992): 1530–48. http://dx.doi.org/10.1139/e92-121.

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As part of the Lithoprobe Southern Cordillera transect, seismic refraction data were recorded along a 330 km long strike profile in the Intermontane belt. An iterative combination of two-dimensional traveltime inversion and amplitude forward modelling was used to interpret crust and upper mantle P-wave velocity structure. This region is characterized by (i) a thin near-surface layer with large variations in velocity between 2.8 and 5.4 km/s, and low-velocity regions that correlate well with surface expressions of Tertiary sedimentary and volcanic rocks; (ii) an upper and middle crust with low average velocity gradient, possibly a weak low-velocity zone, and lateral velocity variations between 6.0 and 6.4 km/s; (iii) a distinctive lower crust characterized by significantly higher average velocities relative to midcrustal values beginning at 23 km depth, approximately 8 km thick with average velocities of 6.5 and 6.7 km/s at top and base; (iv) a depth to Moho, as defined by wide-angle reflections, that averages 33 km with variations up to 2 km; and (v) a Moho transition zone of depth extent 1–3 km, below which lies the upper mantle with velocities decreasing from 7.9 km/s in the south to 7.7 km/s in the north. Where the refraction line obliquely crosses a Lithoprobe deep seismic-reflection profile, good agreement is obtained between the interpreted reflection section and the derived velocity structure model. In particular, depths to wide-angle reflectors in the upper crust agree with depths to prominent reflection events, and Moho depths agree within 1 km. From this comparison, the upper and middle crust probably comprise the upper part of the Quesnellia terrane. The lower crust from the refraction interpretation does not show the division into two components, parautochthonous and cratonic North America, that is inferred from the reflection data, indicating that their physical properties are not significantly different within the resolution of the refraction data. Based on these interpretations, the lower lithosphere of Quesnellia is absent and presumably was recycled in the mantle. At a depth of ~ 16 km below the Moho, an upper mantle reflector may represent the base of the present lithosphere.

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14

Liu, Si-qi, Zhen-yu Ma, Jian Pei, Qing-bin Jiao, Lin Yang, Wei Zhang, Hui Li, Yu-hang Li, Yu-bo Zou, and Xin Tan. "A review of anomalous refractive and reflective metasurfaces." Nanotechnology and Precision Engineering 5, no. 2 (June 1, 2022): 025001. http://dx.doi.org/10.1063/10.0010119.

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Abnormal refraction and reflection refers to the phenomenon in which light does not follow its traditional laws of propagation and instead is subject to refraction and reflection at abnormal angles that satisfy a generalization of Snell’s law. Metasurfaces can realize this phenomenon through appropriate selection of materials and structural design, and they have a wide range of potential applications in the military, communications, scientific, and biomedical fields. This paper summarizes the current state of research on abnormal refractive and reflective metasurfaces and their application scenarios. It discusses types of abnormal refractive and reflective metasurfaces based on their tuning modes (active and passive), their applications in different wavelength bands, and their future development. The technical obstacles that arise with existing metasurface technology are summarized, and prospects for future development and applications of abnormal refractive and reflective metasurfaces are discussed.

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15

Clowes, Ron M., Philip TC Hammer, Gabriela Fernández-Viejo, and J. Kim Welford. "Lithospheric structure in northwestern Canada from Lithoprobe seismic refraction and related studies: a synthesis." Canadian Journal of Earth Sciences 42, no. 6 (June 1, 2005): 1277–93. http://dx.doi.org/10.1139/e04-069.

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The SNORCLE refraction wide-angle reflection (R/WAR) experiment, SNORE'97, included four individual lines along the three transect corridors. A combination of SNORE'97 results with those from earlier studies permits generation of a 2000 km long lithospheric velocity model that extends from the Archean Slave craton to the present Pacific basin. Using this model and coincident near-vertical incidence (NVI) reflection data and geological information, an interpreted cross section that exemplifies 4 Ga of lithospheric development is generated. The velocity structural models correlate well with the reflection sections and provide additional structural, compositional, and thermal constraints. Geological structures and some faults are defined in the upper crust. At a larger scale, the seismic data identify a variety of orogenic styles ranging from thin- to thick-skinned accretion in the Cordillera and crustal-scale tectonic wedging associated with both Paleoproterozoic and Mesozoic collisions. Models of Poisson's ratio support the NVI interpretation that a thick wedge of cratonic metasediments underlies the eastern accreted Cordilleran terranes. Despite the variety of ages, orogenic styles, and tectono-magmatic deformations that are spanned by the seismic corridors, the Moho remains remarkably flat and shallow (3336 km) across the majority of the transect. Significant variations only occur at major tectonic boundaries. Laterally variable crustal velocities are consistently slower beneath the Cordillera than beneath the cratonic crust. This is consistent with the high temperatures (800900 °C) required by the slow upper mantle velocities (7.87.9 km/s) observed beneath much of the Cordillera. Heterogeneity of the lithospheric mantle is indicated by wide-angle reflections below the Precambrian domains and the western Cordillera.

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16

Rawlinson, N., G. A. Houseman, and C. D. N. Collins. "Inversion of seismic refraction and wide-angle reflection traveltimes for three-dimensional layered crustal structure." Geophysical Journal International 145, no. 2 (May 2001): 381–400. http://dx.doi.org/10.1046/j.1365-246x.2001.01383.x.

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17

Zhao, Junmeng, Zhijun Jin, Walter D. Mooney, Nihal Okaya, Shangxu Wang, Xing Gao, Liangjie Tang, Shunping Pei, Hongbing Liu, and Qiang Xu. "Crustal structure of the central Qaidam basin imaged by seismic wide-angle reflection/refraction profiling." Tectonophysics 584 (January 2013): 174–90. http://dx.doi.org/10.1016/j.tecto.2012.09.005.

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18

Ruiz, M., J. Díaz, D. Pedreira, J. Gallart, and J. A. Pulgar. "Crustal structure of the North Iberian continental margin from seismic refraction/wide-angle reflection profiles." Tectonophysics 717 (October 2017): 65–82. http://dx.doi.org/10.1016/j.tecto.2017.07.008.

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19

Iwasaki, Takaya, Wataru Kato, Takeo Moriya, Akiko Hasemi, Norihito Umino, Tomomi Okada, Kaoru Miyashita, et al. "Extensional structure in Northern Honshu Arc as inferred from seismic refraction/wide-angle reflection profiling." Geophysical Research Letters 28, no. 12 (June 15, 2001): 2329–32. http://dx.doi.org/10.1029/2000gl012783.

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20

Zelt, C. A., and B. C. Zelt. "Study of out-of-plane effects in the inversion of refraction/wide-angle reflection traveltimes." Tectonophysics 286, no. 1-4 (March 1998): 209–21. http://dx.doi.org/10.1016/s0040-1951(97)00266-7.

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21

Burianyk, M. J. A., E. R. Kanasewich, and N. Udey. "Broadside wide-angle seismic studies and three-dimensional structure of the crust in the southeast Canadian Cordillera." Canadian Journal of Earth Sciences 34, no. 8 (August 1, 1997): 1156–66. http://dx.doi.org/10.1139/e17-093.

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Broadside, or fan, recordings of a Lithoprobe seismic refraction – wide-angle reflection experiment in the southeastern Canadian Cordillera show several features further illuminating the crustal structure beyond that previously derived from SCoRE '90 (Southern Cordillera Refraction Experiment of 1990) in-line data. Analysis of a nearly in-line profile centred on Castlegar, British Columbia, shows lower velocities in the upper crust associated with the Purcell Anticlinorium as well as velocity variations that may have some association with the Purcell fault zone. The depth to Moho is almost 38 km, somewhat deeper and on trend with the structure that has been established farther north. The broadside records show high signal-to-noise ratio PmP arrivals (i.e., reflections from the bottom of the crust). These PmP fan picks were analysed in regions away from in-line profiles, providing further measurements of the depth to Moho in the southeastern Cordillera. The analysis of the broadside records combined with the earlier in-line interpretations as well as older crustal seismic measurements make up a relatively high resolution database, compared with most other regions in Canada, from which we have generated maps of depth to Moho and average crustal velocity in the southeastern Cordillera of Canada. The maps show thin, low-velocity crust over much of the region and indicate a high degree of correlation between current crustal seismic properties and regional isotherms.

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22

Zhao, Junmeng, Wenjiao Xiao, Xinfa Chen, Xiaojun Wang, Yong Song, Baoli Bian, Xiankang Zhang, et al. "Mixed crystalline basement of Junggar basin revealed by wide-angle seismic evidence." Earth sciences and subsoil use 44, no. 1 (April 5, 2021): 8–29. http://dx.doi.org/10.21285/2686-9993-2021-44-1-8-29.

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A wide-angle seismic reflection / refraction survey along a ~ 600 km long transect through the Junggar basin from Emin to Qitai allows to receive several images near N-S trending blind faults, which are located at the lower part of the upper crust, the middle crust and the lower crust within the basin and cut up the Moho. These faults, with high seismic velocity and without obvious dislocation, are considered as “extensional faults” formed by north-south compression and east-west extension. These deeply rooted faults provide channels via which basic to ultra-basic materials from upper mantle migrate into the crust and mix up with the crustal material causing thin thickness, high seismic velocity, high density and high magnetic intensity after cooling in the crust of the basin.

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23

Chen, Hsin-Yi, Pei-Tzi Chu, and Shih-Lin Chang. "Single-mode dynamic X-ray diffraction for Si and Si nanowires on Si." Journal of Applied Crystallography 47, no. 1 (January 18, 2014): 285–90. http://dx.doi.org/10.1107/s1600576713030458.

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A method is reported of realizing single-mode diffraction using singly polarized X-ray wide-angle incidence and grazing-emergence diffraction from a bare Si substrate and from Si nanowires on an Si substrate. For a bare Si substrate, the surface-diffracted and specularly reflected beams of single-mode excitation are separated owing to the extremely asymmetric diffraction at grazing emergence. For Si wires on Si, single-mode diffraction is achieved by tuning the X-ray energy or the azimuthal angle under the conditions of total reflection. This finding opens up new opportunities for using crystal diffraction, in addition to optical reflection or refraction, for the design of coherent X-ray optics.

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24

Karpiński, Karol, Sylwia Zielińska-Raczyńska, and David Ziemkiewicz. "Aluminium-Based Plasmonic Sensors in Ultraviolet." Sensors 21, no. 12 (June 14, 2021): 4096. http://dx.doi.org/10.3390/s21124096.

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We theoretically investigate the surface plasmon polaritons (SPPs) generated on an Al film covered by an Al2O3 layer in the context of their application as refractive index sensors. The calculated reflection spectra indicate SPP resonance excited by ultraviolet light, which was affected by the thickness of both the metal and the oxide layers on the surface. With optimized geometry, the system can work as a tunable sensor with a wide UV wavelength range λ∼ 150–300 nm. We report a quality factor of up to 10 and a figure of merit on the order of 9, and these are comparable to the performance of more complicated UV plasmonic nanostructures and allow for the detection of a 1% change of the refraction index. The sensor can operate on the basis of either the incidence angle or wavelength changes. The effect of oxide surface roughness is also investigated with an emphasis on amplitude-based refraction index sensing.

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25

Pylypenko, Vitaliy, and Alexey Goncharov. "Seismic Migration in Near-Vertical and Wide-Angle Reflection and Refraction Studies: Towards a Unified Approach." Exploration Geophysics 31, no. 3 (June 2000): 461–68. http://dx.doi.org/10.1071/eg00461.

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26

Hawman, Robert B., Robert H. Colburn, David A. Walker, and Scott B. Smithson. "Processing and inversion of refraction and wide-angle reflection data from the 1986 Nevada Passcal Experiment." Journal of Geophysical Research 95, B4 (1990): 4657. http://dx.doi.org/10.1029/jb095ib04p04657.

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27

Zelt, Colin A., André M. Hojka, Ernst R. Flueh, and Kirk D. McIntosh. "3D simultaneous seismic refraction and reflection tomography of wide-angle data from the Central Chilean Margin." Geophysical Research Letters 26, no. 16 (August 15, 1999): 2577–80. http://dx.doi.org/10.1029/1999gl900545.

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28

HAI, Yan, YiQing LI, BaoJin LIU, ShuaiJun WANG, CeJun MA, XiangHui SONG, JinRen ZHAO, XiaoGuo DENG, ZhenYu FAN, and BaoFeng LIU. "Velocity structure of the western North China basement from high-resolution wide-angle reflection/refraction profiles." Chinese Science Bulletin 62, no. 36 (December 1, 2017): 4294–306. http://dx.doi.org/10.1360/n972017-00562.

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29

Peng, Miao, Handong Tan, and Max Moorkamp. "Structure‐Coupled 3‐D Imaging of Magnetotelluric and Wide‐Angle Seismic Reflection/Refraction Data With Interfaces." Journal of Geophysical Research: Solid Earth 124, no. 10 (October 2019): 10309–30. http://dx.doi.org/10.1029/2019jb018194.

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30

Grandjean, Gilles, Pol Guennoc, Maurice Recq, and Pedro Andréo. "Refraction/wide-angle reflection investigation of the Cadomian crust between northern Brittany and the Channel Islands." Tectonophysics 331, no. 1-2 (February 2001): 45–64. http://dx.doi.org/10.1016/s0040-1951(00)00235-3.

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31

Ocola, Leonidas C., James H. Luetgert, L. Thomas Aldrich, Robert P. Meyer, and Charles E. Helsey. "Velocity structure of the coastal region of Southern Peru from seismic refraction/wide-angle reflection data." Journal of Geodynamics 20, no. 1 (September 1995): 1–30. http://dx.doi.org/10.1016/0264-3707(94)00026-r.

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32

Fruehn, Juergen, Moritz M. Fliedner, and Robert S. White. "Integrated wide‐angle and near‐vertical subbasalt study using large‐aperture seismic data from the Faeroe—Shetland region." GEOPHYSICS 66, no. 5 (September 2001): 1340–48. http://dx.doi.org/10.1190/1.1487079.

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Acquiring large‐aperture seismic data (38 km maximum offset) along a profile crossing the Faeroe—Shetland basin in the North Atlantic enables us to use wide‐angle reflections and refractions, in addition to conventional streamer data (0–6 km), for subbasalt imaging. The wide‐angle results are complemented and confirmed by images obtained from the conventional near‐vertical‐offset range. Traveltime tomography applied to the wide‐angle data shows a low‐velocity layer (3.5–4.5 km/s) underneath southeastward‐thinning lava flows, suggesting a 2.5–3.0‐km‐thick sedimentary layer. The velocity model obtained from traveltime tomography is used to migrate wide‐angle reflections from large offsets that arrive ahead of the water‐wave cone. The migrated image shows base‐basalt and sub—basalt reflections that are locally coincident with the tomographic boundaries. Application of a new multiple suppression technique and controlled stacking of the conventional streamer data produces seismic sections consistent with the wide‐angle results. Prestack depth migration of the near‐vertical offsets shows a continuous base‐basalt reflection and a clearly defined termination of the basalt flows.

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33

ZHU, Jinfang. "Joint exploration of crustal structure in Fuzhou basin and its vicinities by deep seismic reflection and high-resolution refraction as well as wide-angle reflection/refraction." Science in China Series D 48, no. 7 (2005): 925. http://dx.doi.org/10.1360/04yd0321.

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34

Kanasewich, E. R., Z. Hajnal, A. G. Green, G. L. Cumming, R. F. Mereu, R. M. Clowes, P. Morel-a-l'Huissier, et al. "Seismic studies of the crust under the Williston Basin." Canadian Journal of Earth Sciences 24, no. 11 (November 1, 1987): 2160–71. http://dx.doi.org/10.1139/e87-205.

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The seismic refraction method was used in 1981 to study the crust under the northern half of the Williston Basin, in Saskatchewan. A new method of spatial seismic recording, based on a triangular arrangement of receivers, was used for the first time to obtain three-dimensional structure and velocity information. The broadside seismic refraction and wide-angle reflection data obtained by the technique were of particular value in defining several faulted blocks. These blocks are also characterized by aeromagnetic anomalies trending in a northerly direction. The crustal thickness in the southern part of the western provinces shows large variation ranging from 35 to 50 km. Much of the area is also notable for the presence of one or more low-velocity layers and a high-velocity lower crust. There is good evidence for significant lateral heterogeneity, and detailed deep seismic reflection and refraction studies would likely yield information on dips and strikes of beds and faults around the basin as well as define the properties of the various terranes of the Hudsonian mobile belt.

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35

Collins, C. D. N., J. P. Cull, J. B. Colweli, J. B. Willcox, and P. E. Williamson. "DEEP STRUCTURAL IMAGING FROM ONSHORE RECORDING OF A MARINE AIR-GUN SOURCE IN THE GIPPSLAND AND BASS BASINS." APPEA Journal 31, no. 1 (1991): 261. http://dx.doi.org/10.1071/aj90020.

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In 1988 and 1989, the Bureau of Mineral Resources (BMR) completed two regional seismic reflection surveys in the Gippsland and Bass Basins. Seismic arrivals from the routine air-gun shots fired during these surveys were recorded on land by BMR and the Department of Earth Sciences, Monash University. Individual analogue and digital recording stations were deployed in Victoria, Tasmania and Deal Island on the Bassian Rise. Long-offset wide-angle reflection and refraction data were obtained at these stations from traverses across both basins.The data quality was variable, depending on local site conditions, but useful arrivals were observed over 200 km away from the source on some lines. The close shot spacing, either 37.5 or 50 m, and the large number of shots, up to 5000 per traverse, provides the opportunity for stacking and other signal enhancement techniques in areas of poor data quality.The arrival times of the refracted events show significant delays corresponding to changes in basin sediment thickness. Preliminary results suggest no major asymmetry in the rifting process, which would require modification in the current models for rifting of the basins. Sediment and basement apparent velocities obtained from near-station records range from 4.8 to 5.1 km/s; below the deepest part of the basin, the basement apparent velocity is around 5.6 km/s. Deep crustal/upper mantle velocities of 7.2 km/s, and around 8 km/s, are also observed.These velocities, combined with the coincident reflection data provide critical constraints on models of basement geometry. The refraction and wide-angle reflection data can be used to derive the crustal structure associated with the basins and surrounding margins. These sections will complement deep reflection profiling to test and refine tectonic models to guide further exploration.

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36

ZHAO, Jin-Ren, Xian-Kang ZHANG, Cheng-Ke ZHANG, Jian-Shi ZHANG, Zhuo-Xin YANG, Bao-Feng LIU, Bao-Jin LIU, and Cheng-Bin ZHAO. "Deep Structural Features of the Sanhe-Pinggu Strong Earthquake Area Imaged by Wide Angle Reflection / Refraction and Deep Seismic Reflection Profiling." Chinese Journal of Geophysics 47, no. 4 (July 2004): 736–44. http://dx.doi.org/10.1002/cjg2.3544.

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37

Holbrook, W. Steven, G. M. Purdy, J. A. Collins, R. E. Sheridan, D. L. Musser, L. Glover, M. Talwani, J. I. Ewing, R. Hawman, and S. B. Smithson. "Deep velocity structure of rifted continental crust, U.S. Mid-Atlantic Margin, from wide-angle reflection/refraction data." Geophysical Research Letters 19, no. 16 (August 21, 1992): 1699–702. http://dx.doi.org/10.1029/92gl01799.

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38

Takeda, Tetsuya, Hiroshi Sato, Takaya Iwasaki, Nobuhisa Matsuta, Shin’ichi Sakai, Takashi Iidaka, and Aitaro Kato. "Crustal structure in the northern Fossa Magna region, central Japan, modeled from refraction/wide-angle reflection data." Earth, Planets and Space 56, no. 12 (December 2004): 1293–99. http://dx.doi.org/10.1186/bf03353353.

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39

Keller, G. R., L. W. Braile, G. A. McMechan, William A. Thomas, Steven H. Harder, Wen-Fong Chang, and W. G. Jardine. "Paleozoic continent-ocean transition in the Ouachita Mountains imaged from PASSCAL wide-angle seismic reflection-refraction data." Geology 17, no. 2 (1989): 119. http://dx.doi.org/10.1130/0091-7613(1989)017<0119:pcotit>2.3.co;2.

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40

Murty, A. S. N., D. M. Mall, P. R. K. Murty, and P. R. Reddy. "Two-dimensional Crustal Velocity Structure along Hirapur-Mandla Profile from Seismic Refraction and Wide-angle Reflection Data." Pure and Applied Geophysics 152, no. 2 (July 1, 1998): 247–66. http://dx.doi.org/10.1007/s000240050153.

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41

Tian, Xiaofeng, Colin A. Zelt, Fuyun Wang, Shixu Jia, and Qiaoxia Liu. "Crust structure of the North China Craton from a long-range seismic wide-angle-reflection/refraction data." Tectonophysics 634 (November 2014): 237–45. http://dx.doi.org/10.1016/j.tecto.2014.07.008.

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42

Shuai-Jun, WANG, WANG Fu-Yun, ZHANG Jian-Shi, LIU Bao-Feng, ZHANG Cheng-Ke, ZHAO Jin-Ren, DUAN Yu-Ling, et al. "A STUDY OF DEEP SEISMOGENIC ENVIRONMENT IN LUSHANMS7.0 EARTHQUAKE ZONE BY WIDE-ANGLE SEISMIC REFLECTION/REFRACTION PROFILE." Chinese Journal of Geophysics 58, no. 5 (September 2015): 474–85. http://dx.doi.org/10.1002/cjg2.20188.

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43

Huang, Huaiyong, Carl Spencer, and Alan Green. "A method for the inversion of refraction and reflection travel times for laterally varying velocity structures." Bulletin of the Seismological Society of America 76, no. 3 (June 1, 1986): 837–46. http://dx.doi.org/10.1785/bssa0760030837.

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Abstract In an attempt to speed up the lengthy process of modeling seismic refraction/wide-angle reflection data, a two-dimensional ray tracing routine is used as the basis for an automated travel-time inversion scheme. Laterally varying P-wave velocity structures are represented by arbitrary-shaped blocks of constant velocity gradient. Velocities, gradients, and boundary points of the blocks are parameters in the inversion scheme, and the input data are refraction and reflection travel-time arrivals from both directions of a reversed seismic line. Damped least-squares techniques are used to solve the equations of condition, and inversions are allowed to proceed automatically for several iterations. A synthetic example is presented, and the data from two reversed seismic refraction profiles recorded recently in eastern Canada are inverted to demonstrate the utility of the method under less than ideal conditions. The synthetic test demonstrates that several iterations of the procedure are necessary for accurate recovery of input models and provides a resolving power analysis of the problem, while the real data example produces models comparable to those obtained by experienced interpreters using trial and error methods.

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44

Collins, C. D. N., J. P. Cull, J. B. Willcox, and J. B. Colwell. "A long-offset seismic reflection and refraction study of the Gippsland and Bass Basins from onshore recording of a marine air-gun source." Exploration Geophysics 20, no. 2 (1989): 293. http://dx.doi.org/10.1071/eg989293.

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Seismic refraction data were obtained for the Bass and Gippsland Basins during the 1988 cruise of the BMR research vessell "Rig Seismic". Seismic recorders were deployed on land by BMR and Monash University to record long-offset wide-angle reflection and refraction data using the ship's air-guns as the energy source. Preliminary results have now been obtained from these data providing information on deep crustal structure related to the basin formation. Two crustal layers have been detected with velocities of 4.5 km/s increasing to 7.4 km/s (unreversed) at depths exceeding 20 km. Additional data have now been obtained over a traverse length of 170 km to provide constraints on the deep structure of Bass Strait and the Lachlan Fold Belt in Victoria and Tasmania.

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45

Funck, Thomas, and Keith E. Louden. "Wide-angle seismic imaging of pristine Archean crust in the Nain Province, Labrador." Canadian Journal of Earth Sciences 35, no. 6 (June 1, 1998): 672–85. http://dx.doi.org/10.1139/e98-019.

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A detailed refraction - wide-angle reflection seismic experiment was carried out in northern Labrador to determine the velocity structure of relatively unaltered Archean crust in the Nain Province. Six 3-component land seismometers were used to record an airgun source along a profile parallel to the coast. Forward modeling of traveltimes and amplitudes yields a P- and S-wave velocity model that shows two crustal blocks separated by a fault. Magnetic data suggest, but do not prove, that the fault is the offshore continuation of the Handy fault. A southwards thickening of the lower crust across the fault indicates that a transcurrent component might have been associated with the faulting. The total crustal thickness is 33 km to the north and 38 km to the south of the fault. The presence of PmS reflections imply a sharp transition at the Moho. Upper crustal velocities of 5.8-6.3 km/s and Poisson's ratios of 0.20 and 0.24, north and south of the fault respectively, are consistent with a gneissic composition, but suggest a higher quartz content in the northern block. Velocities in the middle crust increase to 6.5 km/s, where a discontinuity at a depth between 16 and 18 km marks the transition to the lower crust with velocities between 6.6 and 6.9 km/s. Poisson's ratios of 0.24 and 0.26 indicate, respectively, a felsic middle crust and an intermediate composition for the lower crust. The absence of a high-velocity basal layer is in accordance with other examples of Archean crust.

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Soares, José E. P., Randell Stephenson, Reinhardt A. Fuck, Marcus V. A. G. de Lima, Vitto C. M. de Araújo, Flávio T. Lima, Fábio A. S. Rocha, and Cíntia R. da Trindade. "Structure of the crust and upper mantle beneath the Parnaíba Basin, Brazil, from wide-angle reflection–refraction data." Geological Society, London, Special Publications 472, no. 1 (2018): 67–82. http://dx.doi.org/10.1144/sp472.9.

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47

Tondi, R., R. De Franco, and R. Barzaghi'. "Sequential integrated inversion of refraction and wide-angle reflection traveltimes and gravity data for two-dimensional velocity structures." Geophysical Journal International 141, no. 3 (June 1, 2000): 679–98. http://dx.doi.org/10.1046/j.1365-246x.2000.00104.x.

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48

McCarthy, Jill, Steven P. Larkin, Gary S. Fuis, Robert W. Simpson, and Keith A. Howard. "Anatomy of a metamorphic core complex: Seismic refraction/wide-angle reflection profiling in southeastern California and western Arizona." Journal of Geophysical Research 96, B7 (1991): 12259. http://dx.doi.org/10.1029/91jb01004.

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49

Song, Jianli, Eric A. Hetland, Francis T. Wu, Xiankang Zhang, Guodong Liu, and Zhuoxin Yang. "P-wave velocity structure under the Changbaishan volcanic region, NE China, from wide-angle reflection and refraction data." Tectonophysics 433, no. 1-4 (April 2007): 127–39. http://dx.doi.org/10.1016/j.tecto.2006.09.012.

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50

Arai, Ryuta, Takaya Iwasaki, Hiroshi Sato, Susumu Abe, and Naoshi Hirata. "Collision and subduction structure of the Izu–Bonin arc, central Japan, revealed by refraction/wide-angle reflection analysis." Tectonophysics 475, no. 3-4 (October 2009): 438–53. http://dx.doi.org/10.1016/j.tecto.2009.05.023.

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