imaging the upper mantle beneath turkey and surrounding regions
... This study includes two interdependent sections. The first section presents an analysis of Pn travel times to determine Pn velocity, Pn anisotropy and crustal thickness variations beneath Turkey and surroundings. Between 1999 and 2010, more than 50 000 Pn arrivals are compiled from 700 regional eart ...
... This study includes two interdependent sections. The first section presents an analysis of Pn travel times to determine Pn velocity, Pn anisotropy and crustal thickness variations beneath Turkey and surroundings. Between 1999 and 2010, more than 50 000 Pn arrivals are compiled from 700 regional eart ...
Seismic reflection profiling in the Proterozoic Arunta Block, central
... central value of each gate is assigned the computed energy level for that gate. An example of an energy stack is shown in Fig. 4. The energy stack has a number of advantages, since it allows the interpreter to look at packets of energy rather than the normal display of signal ~plitudes, and is not a ...
... central value of each gate is assigned the computed energy level for that gate. An example of an energy stack is shown in Fig. 4. The energy stack has a number of advantages, since it allows the interpreter to look at packets of energy rather than the normal display of signal ~plitudes, and is not a ...
Moho map of South America from receiver functions and surface
... [Feng et al., 2004], 1700 waveforms [Feng et al., 2007; van der Lee et al., 2001], and 225 Moho depth point constraints (new ones from this study together with the continent‐wide compilation by Feng et al. [2004]), of which 67 lie in Precambrian provinces. For the oceanic parts of our model, where n ...
... [Feng et al., 2004], 1700 waveforms [Feng et al., 2007; van der Lee et al., 2001], and 225 Moho depth point constraints (new ones from this study together with the continent‐wide compilation by Feng et al. [2004]), of which 67 lie in Precambrian provinces. For the oceanic parts of our model, where n ...
(2005, April). Beyond the thermal plume paradigm. Geophys. Res
... paradigms based on the dynamics of purely thermal axisymmetric plumes. The head-tail structure is possible but not unique and the lack of a plume head does not preclude a deep origin. Our results suggest that the surface expression of some thermo-chemical plumes may be a headless, age-progressive vo ...
... paradigms based on the dynamics of purely thermal axisymmetric plumes. The head-tail structure is possible but not unique and the lack of a plume head does not preclude a deep origin. Our results suggest that the surface expression of some thermo-chemical plumes may be a headless, age-progressive vo ...
A mechanism for preseismic steady rupture fronts observed in
... (PMMA), Rubinstein et al. [2004] observed a slow detachment front propagating at 5% of the S‐wave speed (Vs) after the passage of a supershear rupture front. More recently, Nielsen et al. [2010] reported steady rupture fronts systematically propagating at about 5% of Vs on experimental faults where ...
... (PMMA), Rubinstein et al. [2004] observed a slow detachment front propagating at 5% of the S‐wave speed (Vs) after the passage of a supershear rupture front. More recently, Nielsen et al. [2010] reported steady rupture fronts systematically propagating at about 5% of Vs on experimental faults where ...
Aftershock observation of the 2011 off the Pacific coast of... by using ocean bottom seismometer network
... the sediment, the estimated travel times of P- and S-waves calculated by the location program for OBSs must be corrected. The V p /Vs ratio of 3 is assumed to calculate S-wave correction value for the sedimentary layer. Hypocenters were determined by the maximumlikelihood estimation technique of Hir ...
... the sediment, the estimated travel times of P- and S-waves calculated by the location program for OBSs must be corrected. The V p /Vs ratio of 3 is assumed to calculate S-wave correction value for the sedimentary layer. Hypocenters were determined by the maximumlikelihood estimation technique of Hir ...
Complex seismic trace analysis and its application to time
... 1975). Partyka (2000) and Bodine (1984) defined the response energy, phase and frequency as the instantaneous amplitude, phase and frequency at the maximum of an energy lobe and demonstrated that the response frequency and phase are a measure of the dominant frequency and phase of this lobe. In this ...
... 1975). Partyka (2000) and Bodine (1984) defined the response energy, phase and frequency as the instantaneous amplitude, phase and frequency at the maximum of an energy lobe and demonstrated that the response frequency and phase are a measure of the dominant frequency and phase of this lobe. In this ...
The lowermost mantle beneath northern Asia—II. Evidence for lower
... We have analysed prediffracted S-waves with turning points beneath northern Siberia in a study of anisotropy in the lowermost mantle. Deep-focus earthquakes beneath the Marianas, Izu Bonin and the Sea of Japan recorded at stations in western Europe are used. A correction for upper-mantle anisotropy ...
... We have analysed prediffracted S-waves with turning points beneath northern Siberia in a study of anisotropy in the lowermost mantle. Deep-focus earthquakes beneath the Marianas, Izu Bonin and the Sea of Japan recorded at stations in western Europe are used. A correction for upper-mantle anisotropy ...
Crustal structure of the ultra-slow spreading Knipovich Ridge, North
... the Knipovich Ridge. The first line was acquired 40 km north of a topographic high occurring at *76°300 N. Based on the bathymetry available at this time we believed that underlying crust could be amagmatic. However, a study by Hellevang and Pedersen (2005) demonstrated the magmatic nature of the en ...
... the Knipovich Ridge. The first line was acquired 40 km north of a topographic high occurring at *76°300 N. Based on the bathymetry available at this time we believed that underlying crust could be amagmatic. However, a study by Hellevang and Pedersen (2005) demonstrated the magmatic nature of the en ...
Multi-mode conversion imaging of the subducted Gorda and Juan
... e.g. Alaska (Rondenay et al., 2008), Cascadia (Bostock et al., 2002; Abers et al., 2009), Costa Rica and Nicaragua (MacKenzie et al., 2010), western Hellenic (Suckale et al., 2009), and central Mexico (Kim et al., 2012). In this paper, we use a multiple mode conversion imaging technique that explici ...
... e.g. Alaska (Rondenay et al., 2008), Cascadia (Bostock et al., 2002; Abers et al., 2009), Costa Rica and Nicaragua (MacKenzie et al., 2010), western Hellenic (Suckale et al., 2009), and central Mexico (Kim et al., 2012). In this paper, we use a multiple mode conversion imaging technique that explici ...
Atlantic Ridge − spreading Mid − Evidence for accumulated melt
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... To subscribe to Phil. Trans. R. Soc. Lond. A go to: http://rsta.royalsocietypublishing.org/subscriptions ...
Sample Papers 1 - Entrance
... in length. 12. Bulk stress : If a body is subjected to the same force normally on all its faces such that there is a change in its volume, the normal force per unit area is called bulk stress or volume stress. 13. Bulk stress is equal to pressure or change in pressure also called hydraulic pressure. ...
... in length. 12. Bulk stress : If a body is subjected to the same force normally on all its faces such that there is a change in its volume, the normal force per unit area is called bulk stress or volume stress. 13. Bulk stress is equal to pressure or change in pressure also called hydraulic pressure. ...
Very low frequency earthquakes excited by the 2004 off the... earthquakes: A dynamic deformation process in the large accretionary prism
... around 10 to 20 seconds and there is little or no high frequency content. Therefore these earthquakes are not detected by regional and global seismic observation networks and not listed on any earthquake catalogs. These earthquakes are distributed along the Nankai trough in the Tokai, Kii peninsula, ...
... around 10 to 20 seconds and there is little or no high frequency content. Therefore these earthquakes are not detected by regional and global seismic observation networks and not listed on any earthquake catalogs. These earthquakes are distributed along the Nankai trough in the Tokai, Kii peninsula, ...
Constraints on the source parameters of low
... generated by shear slip, but when compared to earthquakes of similar magnitude, LFEs are depleted in high-frequency content and have lower corner frequencies, implying longer durations. On the Parkfield section of the San Andreas Fault, as in many subduction zones, LFEs occur in rapid succession form ...
... generated by shear slip, but when compared to earthquakes of similar magnitude, LFEs are depleted in high-frequency content and have lower corner frequencies, implying longer durations. On the Parkfield section of the San Andreas Fault, as in many subduction zones, LFEs occur in rapid succession form ...
The Uses and Limitations of the Square-Root
... to characterize sites in recent GMPEs (and Boore et al., 2011, show that V S30 correlates well with V Sz , for averaging depths z both less than and much greater than 30 m). The amplification A in equation (1) can be thought of as the amplitude along the ray tube, projected onto a plane representing ...
... to characterize sites in recent GMPEs (and Boore et al., 2011, show that V S30 correlates well with V Sz , for averaging depths z both less than and much greater than 30 m). The amplification A in equation (1) can be thought of as the amplitude along the ray tube, projected onto a plane representing ...
Mantle Discontinuities - Northwestern University
... km. By observing SH-polarized ScS, and sScS, mantle reverberations, Revenaugh and Jordan [1987, 1989, 1990a, 1990bl obtain a normal-incidence reflection coefficient of 0.072kO.010 at 660 km, for which they suggest a Vs contrast of about 8.5% and a density contrast of 6.1%. Their travel time correlat ...
... km. By observing SH-polarized ScS, and sScS, mantle reverberations, Revenaugh and Jordan [1987, 1989, 1990a, 1990bl obtain a normal-incidence reflection coefficient of 0.072kO.010 at 660 km, for which they suggest a Vs contrast of about 8.5% and a density contrast of 6.1%. Their travel time correlat ...
Oscillation and wave motion
... displacement from the mean position is known as the amplitude of oscillation. If we consider pendulum, we can observe that farther is the point from which pendulum bob (within the permissible limit in which the bob executes SHM) is released, greater is the amplitude of oscillation. Similarly, greate ...
... displacement from the mean position is known as the amplitude of oscillation. If we consider pendulum, we can observe that farther is the point from which pendulum bob (within the permissible limit in which the bob executes SHM) is released, greater is the amplitude of oscillation. Similarly, greate ...
Reply to comment by Hillis et al.(2013)
... then a horizontal shortening, f, of 1.15–1.3 is required to achieve a regional denudation of 1.5–3 km. Given that the British Isles is ∼1000 km long, we expect to see evidence for 130–230 km of horizontal shortening over this distance. There are at most ∼7 documented belts of Cenozoic shortening in ...
... then a horizontal shortening, f, of 1.15–1.3 is required to achieve a regional denudation of 1.5–3 km. Given that the British Isles is ∼1000 km long, we expect to see evidence for 130–230 km of horizontal shortening over this distance. There are at most ∼7 documented belts of Cenozoic shortening in ...
Joint location of microseismic events in the
... ignores important information that couples data from different events and thus ties them together. Event locations are usually understood in either absolute or relative terms (Slunga et al., 1995). Absolute locations are defined globally with respect to a fixed coordinate system. Relative location i ...
... ignores important information that couples data from different events and thus ties them together. Event locations are usually understood in either absolute or relative terms (Slunga et al., 1995). Absolute locations are defined globally with respect to a fixed coordinate system. Relative location i ...
Determining crustal structure beneath seismic stations overlying a
... PbS phase, with one S wave leg in the sedimentary layer; see Figure 1a) can become so high that the direct P wave is usually completely masked. Such RFs are characterized by a delayed first peak corresponding to the arrival of the PbS [Yeck et al., 2013] (Figure 2a). The large impedance contrasts acr ...
... PbS phase, with one S wave leg in the sedimentary layer; see Figure 1a) can become so high that the direct P wave is usually completely masked. Such RFs are characterized by a delayed first peak corresponding to the arrival of the PbS [Yeck et al., 2013] (Figure 2a). The large impedance contrasts acr ...
shear-wave splitting, new geophysics, and earthquake stress
... Transversely-polarised seismic shear waves propagating through in situ rocks with some form of elastic anisotropy, such as aligned microcracks, split into two orthogonal polarisations which propagate with different velocities, and hence lead to shear-wave splitting. The polarisations are strictly or ...
... Transversely-polarised seismic shear waves propagating through in situ rocks with some form of elastic anisotropy, such as aligned microcracks, split into two orthogonal polarisations which propagate with different velocities, and hence lead to shear-wave splitting. The polarisations are strictly or ...
M. Koch
... 4. Solving the inverse problem 4.1. Nonlinear optimization formulation The (nonlinear) seismic forward (travel time) relationship between model m and data d d = g(m) is formulated as a nonlinear least-squares optimization problem for the objective function ||d - g(m) ||2 -> minimum Solution methods ...
... 4. Solving the inverse problem 4.1. Nonlinear optimization formulation The (nonlinear) seismic forward (travel time) relationship between model m and data d d = g(m) is formulated as a nonlinear least-squares optimization problem for the objective function ||d - g(m) ||2 -> minimum Solution methods ...
Geophys. J. Int. 2015 Palacios 1084 100
... Seismic noise is characterized by a continuous record which is permanently observed over time. Its sources can be cultural or natural. In general, cultural sources are related to high frequencies showing daily, weekly or seasonal periodicities. Peterson (1993) collected noise spectra from a variety ...
... Seismic noise is characterized by a continuous record which is permanently observed over time. Its sources can be cultural or natural. In general, cultural sources are related to high frequencies showing daily, weekly or seasonal periodicities. Peterson (1993) collected noise spectra from a variety ...
The seismic Travel Time Problem as applied to Tomography of the
... 4. Solving the inverse problem 4.1. Nonlinear optimization formulation The (nonlinear) seismic forward (travel time) relationship between model m and data d d = g(m) is formulated as a nonlinear least-squares optimization problem for the objective function ||d - g(m) ||2 -> minimum Solution methods ...
... 4. Solving the inverse problem 4.1. Nonlinear optimization formulation The (nonlinear) seismic forward (travel time) relationship between model m and data d d = g(m) is formulated as a nonlinear least-squares optimization problem for the objective function ||d - g(m) ||2 -> minimum Solution methods ...
GDC2007_Catto_Erin_Physics1
... Apply constraint forces to ensure the new state satisfies the constraints. We must solve for the constraint forces because they are implicit. ...
... Apply constraint forces to ensure the new state satisfies the constraints. We must solve for the constraint forces because they are implicit. ...
Surface wave inversion
Inversion is the set of methods used to infer properties through physical measurements. Surface wave inversion is the method by which elastic properties, density, and thickness of layers in the subsurface are attained through analysis of surface wavedispersion. The entire inversion process requires the gathering of seismic data, the creation of dispersion curves, and finally the inference of subsurface properties.