univERsity oF copEnhAGEn
... The Baltic Fennoscandian Shield in Norden includes an Archaean block (chiefly 2.9–2.7 Ga), located in the Kola-Karelian provinces of Finland and Russia, to which a series of terranes (Svecofennia) were accreted during the late Proterozoic (2.0–1.8 Ga) (Gaal and Gorbatschev, 1987). The southern part ...
... The Baltic Fennoscandian Shield in Norden includes an Archaean block (chiefly 2.9–2.7 Ga), located in the Kola-Karelian provinces of Finland and Russia, to which a series of terranes (Svecofennia) were accreted during the late Proterozoic (2.0–1.8 Ga) (Gaal and Gorbatschev, 1987). The southern part ...
Seismic character of volcanic activity at the ultraslow
... to define the duration of volcanic activity and mechanics of emplacement. The consistent event rate and volcanic character of the earliest activity suggest that volcanism began immediately and continued at least until April 15, when there was a distinct decrease in the rate of activity (Fig. 2A). Be ...
... to define the duration of volcanic activity and mechanics of emplacement. The consistent event rate and volcanic character of the earliest activity suggest that volcanism began immediately and continued at least until April 15, when there was a distinct decrease in the rate of activity (Fig. 2A). Be ...
3-D crustal structure of the extensional Granada Basin in the
... especially sandstone, porosity is much higher and does not completely close at elevated pressures and so will have a dominant influence on seismic velocities. For most common rock types, velocity decreases with increasing temperature. Velocities have been found to correlate well with mineralogy at p ...
... especially sandstone, porosity is much higher and does not completely close at elevated pressures and so will have a dominant influence on seismic velocities. For most common rock types, velocity decreases with increasing temperature. Velocities have been found to correlate well with mineralogy at p ...
Geology 305 with Terry J. Boroughs: The Dynamic Earth Homework
... A zone 105° to 142° from the epicenter of an earthquake in which there is no penetration of seismic waves through the Earth. ...
... A zone 105° to 142° from the epicenter of an earthquake in which there is no penetration of seismic waves through the Earth. ...
Deep crustal fracture zones control fluid escape and the seismic
... (same as Fig. 2d). (b) Results of our modeling using the second input model where no interface (Conrad) is set in the crust. No fictitious interface appears near 15 km depth, suggesting that the mid-crustal discontinuity does not result from cross-mode contamination. (c) Result of our modeling using ...
... (same as Fig. 2d). (b) Results of our modeling using the second input model where no interface (Conrad) is set in the crust. No fictitious interface appears near 15 km depth, suggesting that the mid-crustal discontinuity does not result from cross-mode contamination. (c) Result of our modeling using ...
Atlantic Ridge − spreading Mid − Evidence for accumulated melt
... velocity reaches 6.5 km s−1 at a depth of 2.0–2.5 km below the seafloor. Below this level, which we interpret as the boundary between seismic layers 2 and 3, P-wave velocity increases more slowly with depth, reaching about 7 km s−1 just above the crust–mantle boundary, which occurs at between 6 and ...
... velocity reaches 6.5 km s−1 at a depth of 2.0–2.5 km below the seafloor. Below this level, which we interpret as the boundary between seismic layers 2 and 3, P-wave velocity increases more slowly with depth, reaching about 7 km s−1 just above the crust–mantle boundary, which occurs at between 6 and ...
An integrated geophysical analysis of crustal structure in the Wichita
... of reflectors down to 30 km, with less coherent reflectors visible to a depth of 45 km. A strong reflector at 17 km that shallows to 14 km towards the north is inferred to represent the bottom of the basin. Zhu and McMechan (1989) developed a 2-D P-wave velocity model to a depth of ~15 km. They foun ...
... of reflectors down to 30 km, with less coherent reflectors visible to a depth of 45 km. A strong reflector at 17 km that shallows to 14 km towards the north is inferred to represent the bottom of the basin. Zhu and McMechan (1989) developed a 2-D P-wave velocity model to a depth of ~15 km. They foun ...
Seismic pore pressure prediction with uncertainty using a
... performed point by point in the 3-D P-MEM, with a Gaussian PDF specified at each location for all uncertain input variables. Input PDFs for porosity, clay content, overburden pressure and seismic velocity are spatially variable, while PDFs for the uncertain coefficients ai are assumed to be spatiall ...
... performed point by point in the 3-D P-MEM, with a Gaussian PDF specified at each location for all uncertain input variables. Input PDFs for porosity, clay content, overburden pressure and seismic velocity are spatially variable, while PDFs for the uncertain coefficients ai are assumed to be spatiall ...
Master`s Thesis Template
... Figure 4.3. (a) Prestack time migrated seismic section, (b) prestack depth migrated seismic section of the pop-up model shown in Figure 4.2. Note that the depth migration provides a sharper image of the fault discontinuities. Yellow arrows indicate multiples, while blue arrows indicate reflections ...
... Figure 4.3. (a) Prestack time migrated seismic section, (b) prestack depth migrated seismic section of the pop-up model shown in Figure 4.2. Note that the depth migration provides a sharper image of the fault discontinuities. Yellow arrows indicate multiples, while blue arrows indicate reflections ...
MagmastoragebeneathAxialvolcano on the Juan de Fuca mid
... The compressional-velocity image of the volcano presented here is based on data collected during a 1999 active-source seismic experiment (Fig. 1). 5,025 shots from the airgun array (20 guns totalling 142 litres) of the RV Maurice Ewing were recorded on six ocean-bottom seismometers12 deployed on the ...
... The compressional-velocity image of the volcano presented here is based on data collected during a 1999 active-source seismic experiment (Fig. 1). 5,025 shots from the airgun array (20 guns totalling 142 litres) of the RV Maurice Ewing were recorded on six ocean-bottom seismometers12 deployed on the ...
3-D structure of the Rio Grande Rift from 1
... In general, surface waves dominate seismograms as the largest amplitude waves from an earthquake and have observed lower frequencies than body waves. Furthermore, surface wave velocities vary depending on the depth sampled by each period, resulting in dispersion. Measuring dispersion of surface wave ...
... In general, surface waves dominate seismograms as the largest amplitude waves from an earthquake and have observed lower frequencies than body waves. Furthermore, surface wave velocities vary depending on the depth sampled by each period, resulting in dispersion. Measuring dispersion of surface wave ...
Seismic Strengthening of Harborview Medical Center
... Emergency Management Agency's Prestandard and Commentary for the Seismic Rehabilitation of Buildings (FEMA 356) was used as the loading protocol (ASCE, 2000). Each applied load step represents a specific spandrel rotation. Loads were applied in both the positive and negative directions to a target ...
... Emergency Management Agency's Prestandard and Commentary for the Seismic Rehabilitation of Buildings (FEMA 356) was used as the loading protocol (ASCE, 2000). Each applied load step represents a specific spandrel rotation. Loads were applied in both the positive and negative directions to a target ...
Crustal Thickness, Oceanic Lithosphere Distribution and OCT
... Continental lithosphere thinning and post-breakup residual thicknesses of continental crust determined from gravity inversion have been used to predict the preservation of continental crustal radiogenic heat productivity and the transient lithosphere heat-flow contribution within thermally equilibr ...
... Continental lithosphere thinning and post-breakup residual thicknesses of continental crust determined from gravity inversion have been used to predict the preservation of continental crustal radiogenic heat productivity and the transient lithosphere heat-flow contribution within thermally equilibr ...
Investigation of the Low Velocity Layer using Shallow Seismic
... seismic time delays of magnitude dependent on the positions (elevations) of the shot and detector. These time delays, if not accounted for, degrade the reflection seismic section by improper alignment of traces. These near surface zone has various properties. Its top sediments are usually aerated, l ...
... seismic time delays of magnitude dependent on the positions (elevations) of the shot and detector. These time delays, if not accounted for, degrade the reflection seismic section by improper alignment of traces. These near surface zone has various properties. Its top sediments are usually aerated, l ...
Earthquakes
... the Earth comes from the study of seismic waves from earthquakes. Seismic waves from large earthquakes pass throughout the Earth. These waves contain vital information about the internal structure of the Earth. As seismic waves pass through the Earth, they are refracted, or bent, like rays of light ...
... the Earth comes from the study of seismic waves from earthquakes. Seismic waves from large earthquakes pass throughout the Earth. These waves contain vital information about the internal structure of the Earth. As seismic waves pass through the Earth, they are refracted, or bent, like rays of light ...
Earthquakes - PreventionWeb
... Measuring the size of an earthquake We can determine how big an earthquake is by measuring the size of the signal directly from the seismogram. However, we also have to know how far away the earthquake was. This is because the amplitude of the seismic waves decreases with distance, so we must corre ...
... Measuring the size of an earthquake We can determine how big an earthquake is by measuring the size of the signal directly from the seismogram. However, we also have to know how far away the earthquake was. This is because the amplitude of the seismic waves decreases with distance, so we must corre ...
The lithosphere–asthenosphere boundary in the North
... resolution using other techniques. In P-receiver functions, the time window of the LAB arrival is heavily disturbed by crustal reverberations. These reverberations are not present in the S-receiver functions, because the converted phases are S precursors, whereas multiples arrive after the main phas ...
... resolution using other techniques. In P-receiver functions, the time window of the LAB arrival is heavily disturbed by crustal reverberations. These reverberations are not present in the S-receiver functions, because the converted phases are S precursors, whereas multiples arrive after the main phas ...
Composition of the crust and upper-mantle in the central Andes (19
... The present-day crustal structure of the Andean chain results from deformation processes and magmatic activity since the onset of subduction. One line of investigation to resolve questions about the mechanism of crustal thickening is to get information about the composition of the crust and upper-ma ...
... The present-day crustal structure of the Andean chain results from deformation processes and magmatic activity since the onset of subduction. One line of investigation to resolve questions about the mechanism of crustal thickening is to get information about the composition of the crust and upper-ma ...
ReMi Report - The Nevada Seismological Laboratory
... Previous Refraction Microtremor (ReMi) and high resolution Reflection/Refraction surveys have traced a north-south trending fault through downtown Reno, Nevada (Clark, 2005; Scott et al., 2004). During the spring of 2015, a ReMi survey was conducted to find the hypothesized continuation of this faul ...
... Previous Refraction Microtremor (ReMi) and high resolution Reflection/Refraction surveys have traced a north-south trending fault through downtown Reno, Nevada (Clark, 2005; Scott et al., 2004). During the spring of 2015, a ReMi survey was conducted to find the hypothesized continuation of this faul ...