- Wiley Online Library
... procedure iteratively solves for hypocentral separations by minimizing the residuals between observed and predicted travel time differences for pairs of earthquakes observed at common stations. Within the array, the root-mean-square of the differential time residual decreases by about 91% from 0.125 ...
... procedure iteratively solves for hypocentral separations by minimizing the residuals between observed and predicted travel time differences for pairs of earthquakes observed at common stations. Within the array, the root-mean-square of the differential time residual decreases by about 91% from 0.125 ...
The continental tectosphere and Earth`s long
... regions. But, Souriau and Souriau Ž1983. demonstrated that there is a significant correlation between the geoid Žspherical harmonic degrees l s 3–12. and the tectonic regionalization of Okal Ž1977.. From degree-by-degree correlations Ž l s 2–20., Richards and Hager Ž1988. observed a weak association ...
... regions. But, Souriau and Souriau Ž1983. demonstrated that there is a significant correlation between the geoid Žspherical harmonic degrees l s 3–12. and the tectonic regionalization of Okal Ž1977.. From degree-by-degree correlations Ž l s 2–20., Richards and Hager Ž1988. observed a weak association ...
Chapter 2 The Way the Earth Works: Plate Tectonics
... and dropped off enough supplies to last the winter. Wegener and one companion set out on the return trip the next day, but they never made it home. Had Wegener survived to old age, he would have seen his hypothesis become the foundation of a scientific revolution. Today, geologists accept many aspec ...
... and dropped off enough supplies to last the winter. Wegener and one companion set out on the return trip the next day, but they never made it home. Had Wegener survived to old age, he would have seen his hypothesis become the foundation of a scientific revolution. Today, geologists accept many aspec ...
Pyrenean orogeny and plate kinematics
... reprinted with permission from Elsevier Science). Also shown are the locations of the ECORS [Choukroune and ECORS Team, 1989] and ESCI [Vidal et al., 1998] deep seismic reflection profiles, refraction profiles 6 and 8 [Pedreira et al., 2003] (bold lines), and tomographic profiles b to f (dashed line ...
... reprinted with permission from Elsevier Science). Also shown are the locations of the ECORS [Choukroune and ECORS Team, 1989] and ESCI [Vidal et al., 1998] deep seismic reflection profiles, refraction profiles 6 and 8 [Pedreira et al., 2003] (bold lines), and tomographic profiles b to f (dashed line ...
- Arizona State University
... n plane [Zhu and Kanamori, 2000]. The stacked trace amplitude will be maximized where the three modes add constructively, and measurement variances and covariances can be calculated from the solution peak. The main assumptions in this method are that the incoming P wave is essentially a plane wave, ...
... n plane [Zhu and Kanamori, 2000]. The stacked trace amplitude will be maximized where the three modes add constructively, and measurement variances and covariances can be calculated from the solution peak. The main assumptions in this method are that the incoming P wave is essentially a plane wave, ...
International Ocean Discovery Program
... The Chicxulub impact crater, México, is unique. It is the only known terrestrial impact structure that has been directly linked to a mass extinction event and the only terrestrial impact with a global ejecta layer. Of the three largest impact structures on Earth, Chicxulub is the best preserved. Chi ...
... The Chicxulub impact crater, México, is unique. It is the only known terrestrial impact structure that has been directly linked to a mass extinction event and the only terrestrial impact with a global ejecta layer. Of the three largest impact structures on Earth, Chicxulub is the best preserved. Chi ...
Sine et al.
... inevitable. We propose the retention of 1 to 2% melt and a temperature increase of 300 to 500°C beneath the GB produces the strong gradient in seismic velocity across the GB-CP boundary. [9] The contrast in seismic velocity across this boundary is not only large but is also very sharp, and our lim ...
... inevitable. We propose the retention of 1 to 2% melt and a temperature increase of 300 to 500°C beneath the GB produces the strong gradient in seismic velocity across the GB-CP boundary. [9] The contrast in seismic velocity across this boundary is not only large but is also very sharp, and our lim ...
Seismic Waves from the Outer and the Inner Core
... it may well be true from various considerations, among which the observed amplitudes of P’ played an important role. In any case, the assumption of such an hypothesis allowed Jeffreys to obtain travel-time values for PKIKP waves in agreement with those given by observation. Gutenberg in the followin ...
... it may well be true from various considerations, among which the observed amplitudes of P’ played an important role. In any case, the assumption of such an hypothesis allowed Jeffreys to obtain travel-time values for PKIKP waves in agreement with those given by observation. Gutenberg in the followin ...
Mantle plumes, plumes and “plumes”: do we
... 3. Upper mantle is vigorously convecting and hence the source of heat is somewhere below (source is most likely in the D’’ layer); 4. Oceanic island basalts are enriched in incompatible elements compared with depleted mid-oceanic ridge basalts, hence source is primitive in composition (Earth’s lower ...
... 3. Upper mantle is vigorously convecting and hence the source of heat is somewhere below (source is most likely in the D’’ layer); 4. Oceanic island basalts are enriched in incompatible elements compared with depleted mid-oceanic ridge basalts, hence source is primitive in composition (Earth’s lower ...
Hotspot Geodynamics Detailed Planning Group
... as well. This requires drilling at least one deep penetration site per seamount, supplemented with dredging (e.g., from site surveys). Seamount trails may contain tens or hundreds of individual volcanic edifices, while only a few of these can be sampled by IODP drilling. Dredging other seamounts adj ...
... as well. This requires drilling at least one deep penetration site per seamount, supplemented with dredging (e.g., from site surveys). Seamount trails may contain tens or hundreds of individual volcanic edifices, while only a few of these can be sampled by IODP drilling. Dredging other seamounts adj ...
Section 4: Forsyth Barr building - Canterbury Earthquakes Royal
... damage repair. In “1.7.1 Crack Damage”, the contractor is instructed to identify cracks to be repaired following the work detailed within that appendix, and to contact the engineer to arrange an inspection after preparation for, but prior to, epoxy injection or grouting. The stairs were one of the e ...
... damage repair. In “1.7.1 Crack Damage”, the contractor is instructed to identify cracks to be repaired following the work detailed within that appendix, and to contact the engineer to arrange an inspection after preparation for, but prior to, epoxy injection or grouting. The stairs were one of the e ...
Mathematical models of the Earth`s density structure and their
... and Ricard (1996) derived a global model of the crust and upper mantle density structure based on analysis of seismic data and additional constrains such as heat flow and chemical composition. Mooney et al. (1998) compiled the global crustal model with a 5×5 arc-deg spatial resolution. The updated gl ...
... and Ricard (1996) derived a global model of the crust and upper mantle density structure based on analysis of seismic data and additional constrains such as heat flow and chemical composition. Mooney et al. (1998) compiled the global crustal model with a 5×5 arc-deg spatial resolution. The updated gl ...
Attenuation Tomography Beneath the Rocky Mountain Front
... Hessler [1997] produced a similar map from P wave travel time tomography but with smaller variations in P wave velocity, -4% (also summarized by Lerner-Lam et al. [1998]). Li et al. [2002] measured surface wave dispersion and inverted for crustal and upper mantle shear wave velocity. The greatest di ...
... Hessler [1997] produced a similar map from P wave travel time tomography but with smaller variations in P wave velocity, -4% (also summarized by Lerner-Lam et al. [1998]). Li et al. [2002] measured surface wave dispersion and inverted for crustal and upper mantle shear wave velocity. The greatest di ...
SEISMIC RISK ASSESSMENT FOR LARGE DAMS
... The three dams under consideration have been constructed and finished from early 50s to the middle of 60s of the last century. They are critical nodes of national water and power supply systems. Two of the investigated dams are of concrete gravity type and the third is a gravity-arch dam. They are l ...
... The three dams under consideration have been constructed and finished from early 50s to the middle of 60s of the last century. They are critical nodes of national water and power supply systems. Two of the investigated dams are of concrete gravity type and the third is a gravity-arch dam. They are l ...
Peculiarities of roughness and thickness of oceanic crust in the
... (Jackson et al. 1982). Other investigations (Fig. 1a, lines a, d and f) yield a crustal thickness of 6–7 km (Kristoffersen et al. 1982; Duckworth et al. 1982). These results are too sparse in geographical distribution for any systematic match with global models to be perceived. This sparsity is main ...
... (Jackson et al. 1982). Other investigations (Fig. 1a, lines a, d and f) yield a crustal thickness of 6–7 km (Kristoffersen et al. 1982; Duckworth et al. 1982). These results are too sparse in geographical distribution for any systematic match with global models to be perceived. This sparsity is main ...
Buckling instabilities of subducted lithosphere beneath the transition
... The apparent thickening of the slab in the tomographic images – equivalent to about five times the slab thickness – is too large to be easily explained by a mechanism other than buckling. The principal alternative, sometimes called ‘advective’ or ‘pure shear’ thickening, is uniform widening of the s ...
... The apparent thickening of the slab in the tomographic images – equivalent to about five times the slab thickness – is too large to be easily explained by a mechanism other than buckling. The principal alternative, sometimes called ‘advective’ or ‘pure shear’ thickening, is uniform widening of the s ...
Seismic and aseismic deformation along the East African Rift
... together with an extended GPS position time-series allows improved accuracy in determining the velocity field than prior geodetic studies. Using this new velocity field of the whole African continent, the best model proposed here remains consistent with previous studies including the existence of tw ...
... together with an extended GPS position time-series allows improved accuracy in determining the velocity field than prior geodetic studies. Using this new velocity field of the whole African continent, the best model proposed here remains consistent with previous studies including the existence of tw ...
Regionality of deep low-frequency earthquakes associated with
... The JMA hypocenter catalogue includes many LFEs beneath the Kii Peninsula at depths of 30–50 km. To compare the depth ranges of LFEs to the temperature structures calculated in the following section, we selected 21 LFEs with more than 12 arrival-time data that took place within 20 km of the calculat ...
... The JMA hypocenter catalogue includes many LFEs beneath the Kii Peninsula at depths of 30–50 km. To compare the depth ranges of LFEs to the temperature structures calculated in the following section, we selected 21 LFEs with more than 12 arrival-time data that took place within 20 km of the calculat ...
Seismic detection and characterization of the
... Discovery of the APMB Recently we published a study of teleseismic receiver functions for fourteen events recorded by seven PASSCAL broadband stations deployed for one year in the northeast portion of the APVC (CHMIELOWSKI et al., 1999). We used the method of receiver functions to probe the crustal ...
... Discovery of the APMB Recently we published a study of teleseismic receiver functions for fourteen events recorded by seven PASSCAL broadband stations deployed for one year in the northeast portion of the APVC (CHMIELOWSKI et al., 1999). We used the method of receiver functions to probe the crustal ...
Constraints on the source parameters of low
... For each family, we select all relocated earthquakes [Waldhauser and Schaff, 2008; Thurber et al., 2004] with hypocenters at a distance of less than 3 km from the respective LFE family and with catalog magnitudes of 1.4 or below. We also included two aftershocks of an M 2.1 event with a focal mechan ...
... For each family, we select all relocated earthquakes [Waldhauser and Schaff, 2008; Thurber et al., 2004] with hypocenters at a distance of less than 3 km from the respective LFE family and with catalog magnitudes of 1.4 or below. We also included two aftershocks of an M 2.1 event with a focal mechan ...
Mantle deformation beneath the Chicxulub impact crater
... modeled from gravity data, and has been attributed to rapid mantle uplift following impact (e.g., ...
... modeled from gravity data, and has been attributed to rapid mantle uplift following impact (e.g., ...
Magnetotellurics
Magnetotellurics (MT) is an electromagnetic geophysical method for inferring the earth's subsurface electrical conductivity from measurements of natural geomagnetic and geoelectric field variation at the Earth's surface. Investigation depth ranges from 300m below ground by recording higher frequencies down to 10,000m or deeper with long-period soundings. Developed in the USSR and France during the 1950s, MT is now an international academic discipline and is used in exploration surveys around the world. Commercial uses include hydrocarbon (oil and gas) exploration, geothermal exploration, mining exploration, as well as hydrocarbon and groundwater monitoring. Research applications include experimentation to further develop the MT technique, long-period deep crustal exploration, and earthquake precursor prediction research.