We see that part of the reduction in the t misfit for stress is accompanied by a decrease in the stress amplitudes. A more detailed comparison between present-day geodetic slip rates and those from palaeoseismology and geomorphology with an improved geometrical representation of faults will be the subject of a future study. Our approach was inspired by Meade et al. Shaw J. Suppe J. Huftile G.J. Root-cause analysis is defined as the systematic process of investigating an issue using proven techniques to gather data around the problem, identifying more than one cause, prioritizing them, and coming up with potential solutions. What are the physical hazards in the workplace? (2002a) developed an improved block modelling procedure and studied southern California. 1986; Savage & Lisowski 1998), to name a few. More than 250 structures throughout the United States have been outfitted with seismic. Embrace the greens and . While surface traces of faults in southern California have been mapped in great detail (e.g. We have also excluded some data from the dense GPS networks around Parkfield and Anza for a more uniform spatial coverage, and have removed those GPS stations that either we or Shen et al. During the inversion, we allow block L to readjust the reference frame by treating the long-term block motion, L, as a free parameter (see Section 2.3.1 and Tables A1 and A2). In both models, there is little slip on the Elsinore and San Bernardino segments of the SAF. As discussed in Section 2.3, the fault locking depth, dl, is the major control on the width of the transition between vGPS and vp across faults. (2000) and McGill (1989). >First digit: fault visibility code >1 = Well constrained >2 = Moderately constrained >3 = Inferred > >Second digit: fault age code >1 = Historic >2 = Holocene < . To explore the dependence of model results on block geometry, we show as an example strike-slip rates for a = 1 joint inversion with an alternative block geometry around the San Bernardino mountains (Fig. It is therefore important to compare our present-day, interseismically derived fault slip rates with palaeoseismological constraints. However, we found that there are differences in the predicted models, depending on whether we damp towards r using 0, of if we damp by eliminating small SVs in (6). Abstract. More recently, Meade et al. Many factors influence the strength of earthquake shaking at a site including the earthquakes magnitude, the sites proximity to the fault, the local geology, and the soil type. We also found that slightly different predictions for arise for SV elimination depending on the initial reference-frame correction for the GPS velocities. This movement may occur rapidly, in the form of an earthquake - or may occur slowly, in the form of creep. If we use all data from SCEC3, the mean misfit is increased to |v|> 2.4 mm yr-1. These are the only officially recognized short-term "predictions.". A lock () or https:// means youve safely connected to the .gov website. Do we really understand what seismologists are saying? 2(a) for the inversion instead of the smoothed pre-Landers stresses, the mean angular misfit of this strain model is ||> 11.9 for = 1, a comparable misfit to that in the stress inversion. 9) for = 0 velocity-only, and = 1 joint inversion versus global locking depth (= 0.05 and = 0.1). Lindvall S. Herzberg M. Murbach D. Dawson T. Berger G.. Schroeder J.M. 2 compares the results of a Kostrov (1974)-type summation of seismic moment tensors and of a stress inversion of our catalogue from 1981 up to the time of the Landers event in 1992. 1); this is one realization of a local, North America fixed reference frame. Mtg, Geol. Thus, these results indicated that vast high-quality datasets of tsunami deposits can improve the accuracy of paleotsunami source estimation. We have shown that a physical model that is broadly consistent with interseismic velocities and stress from seismicity can be constructed. However, our study roughly confirms the slip-rate partitioning of 6/12/22 mm yr-1 that Bourne et al. Slip is the relative displacement of formerly adjacent points on opposite sides of a fault, measured on the fault surface. Based on the inversion of GPS data only (Fig. 2001), leading us to expect significant viscoelastic effects (cf.McClusky et al. Our goal is to compare these predicted stressing rates with the stress model we derived from focal mechanisms, ignoring for the moment any background stress (e.g. Then the original earthquake is considered a foreshock. Residual GPS velocities v and predicted fault slip rates for a joint inversion of GPS and stress data, = 1 (compare with Fig. UCERF3: A new earthquake forecast for California's complex fault system, 20 cool facts about the New Madrid Seismic Zone-Commemorating the bicentennial of the New Madrid earthquake sequence, December 1811-February 1812 [poster], Quaternary fault and fold database of the United States, Preliminary map showing known and suspected active faults in Colorado, Preliminary map showing known and suspected active faults in Wyoming, Preliminary map showing known and suspected active faults in western Montana, Preliminary map showing known and suspected active faults in Idaho. (1996) and our block model, Fay & Humphreys found higher slip rates along the SAF Indio segment than along the SJF. USGS Earthquake Hazards Program, responsible for monitoring, reporting, and researching earthquakes and earthquake hazards This does not mean the fault slips 33 millimeters each year. Our strike-slip rates agree with Meade et al. Sometimes the change in stress is great enough to trigger aftershocks on nearby faults as well. Our method is different in that we include stress data for the first time and use a different parametrization. See Answer Question: How well constrained is the San Andreas fault? Depending on the assumptions about the stress-drop magnitude with respect to the background stress, this rotatight, however, not persist for a significant fraction of the seismic cycle. 2003). 2001). The L that was subtracted is (-0.16 0.02, -0.34 0.04, 0.25 0.03) for = 0 and (-0.11 0.02, -0.24 0.04, 0.17 0.03) for = 1 in the original SCEC reference frame (ranges indicate 1). 2002). Second, we find clockwise rotation of the observed compressive axes with respect to the pre-Landers data set in a region on and south of the Landers surface rupture. For the inversion used, we have n= 224 locations with stress results, leading to N= 1344 components, of which = 4n are independent. Figure 1 shows the types of faults that can cause earthquakes. (2002) argue for at least 20 mm yr-1 along the northern SJF. An earthquake will be called an aftershock as long as the rate of earthquakes is higher than it was before the mainshock. How do I find fault or hazard maps for California? FTFA problem in [19]). A Quaternary fault is one that has been recognized at the surface and that has moved in the past 1,600,000 years (1.6 million years). We use a high-quality regional focal mechanism catalogue of 5500 events computed using the technique of Hardebeck & Shearer (2002). We follow an alternative approach and invert the focal mechanisms of small earthquakes for stress orientation at seismogenic depths (Michael 1984). An alternative model divides the slip more equally between the Indio SAF and the SJF. Just as you snap your fingers with the whole area of your fingertip and thumb, earthquakes happen over an area of the fault, called the rupture surface. Geographic representation of Euler vectors, , with respect to block L as converted from Table A1. First, we study the Unconstrained Fault-Tolerant Resource Allocation (UFTRA) problem (a.k.a. Many faults are mapped as individual segments across an area. For simplicity, we follow the block modelling (or backslip) method of Savage & Burford (1973). Am., Abstracts with Programs, Global Positioning System constraints on plate kinematics and dynamics in the eastern Mediterranean and Caucasus, Present day kinematics of the Eastern California shear zone from a geodetically constrained block model, Geologic maps of the Pacific Palisades area, Los Angeles, California, Map I-1828, Miscellaneous Investigations Series, Holocene Slip Rate of the Central Garlock Fault in Southeastern Searles Valley, Paleoseismology of the San Andreas fault at Plunge Creek, near San Bernardino, Southern California, The central and southern Elsinore fault zone, southern California, The effect of loading rate on static friction and the rate of fault healing during the earthquake cycle, Block models of present day deformation in Southern California constrained by geodetic measurements (Abstract), Estimates of seismic potential in the Marmara Sea region from block models of secular deformation constrained by Global Positioning System measurements, Determination of stress from slip data; faults and folds, Use of focal mechanisms to determine stress; a control study, Spherical versus flat models of coseismic and postseismic deformations, Internal deformation due to shear and tensile faults in a half-space, Transient strain accumulation and fault interaction in the Eastern California shear zone, SCEC 3D community fault model for southern California (abstract), The relationship between the instantaneous velocity field and the rate of moment release in the lithosphere, Mantle flow beneath a continental strike-slip fault: Postseismic deformation after the 1999 Hector Mine earthquake, Distribution of slip between the San Andreas and San Jacinto faults near San Bernardino, southern California (Abstract), 82nd Ann. Results can be compared with Figs 2(b) and 6(b). The danger of living near fault lines Living near fault lines is inherently dangerous but difficult to avoid. 6 shows the horizontal part of the predicted stress field in our model, both for the GPS-only inversion (Fig. 2(a), deviations from the right-lateral strike-slip regime are mostly found in the Transverse Ranges. Secure .gov websites use HTTPS If you continue to use this site we will assume that you are happy with it. We also predict shortening across the Garlock fault, but this feature is not found in the joint inversion (see below). In the problem, we are given a set of sites equipped with an unconstrained number of facilities as resources, and a set of clients with set \mathcal {R} as corresponding connection requirements, where every facility belonging to . Rather, it stores up 33 millimeters of slip each year to be released in infrequent earthquakes. This indicates that slip rates can be robustly determined. Uncertainties are larger towards the east, and are particularly high around the San Bernardino mountains (sv 4 mm yr-1). The second possibility is that the seismicity inversion detects the stress-rate tensor (Smith & Heaton 2003. Korsh R.J. Shlemon R.J.. Kendrick K.J. 6). 5) and joint ( = 1, Fig. Stein S.. Deng J. Gurnis M. Kanamori H. Hauksson E.. Dolan J.F. An earthquake large enough to cause damage will probably produce several felt aftershocks within the first hour. 2003), 1 mm yr-1 normal (Beanland & Clark 1993). We strive to minimize the effect of curvature in our half-space representation by evaluating displacements in a fault-local oblique Mercator system (Meade et al. Ground shaking is the primary cause of earthquake damage to man-made structures. 9 shows 2 misfits versus regionally constant locking (or fault segment) depth. Faults allow the blocks to move relative to each other. We therefore introduce a damping vector, Late Quaternary history of the Owens Valley fault zone, eastern California, and surface rupture associated with the 1872 earthquake (abstract), Earthquake recurrence time variations with and without fault zone interactions, Global Positioning System constraints on fault slip rates in southern California and northern Baja, Present-day pattern of cordilleran deformation in the western United States, Effects induced by an earthquake on its fault plane: a boundary element study, On the existence of a periodic dislocation cycle in horizontally layered viscoelastic model, The motion of crustal blocks driven by flow of the lower lithosphere and implications for slip rates of continental strike-slip faults, Quaternary geology and seismic hazard of the Sierra Madre and associated faults, western San Gabriel Mountains, Recent Reverse Faulting in the Transverse Ranges, California, Effect of recent revisions to the geomagnetic reversal time scale on estimates of current plate motions, Viscoelastic flow in the lower crust after the 1992 Landers, California, earthquake, Paleoseismology and Global Positioning System; earthquake-cycle effects and geodetic versus geologic fault slip rates in the Eastern California shear zone, Role of the eastern California shear zone in accomodating PacificNorth American plate motion, Prospects for larger or more frequent earthquakes in the Los Angeles metropolitan region, Late Quaternary activity and seismic potential of the Santa Monica fault system, Los Angeles, California, Stratigraphic record of Pleistocene initiation and slip on the Coyote Creek Fault, lower Coyote Creek, Southern California, Contributions to Crustal Evolution of the Southwestern United States, Late pleistocene slip rate on the Coachella Valley segment of the San Andreas fault and implications for regional slip partitioning (abstract), 99th Ann. 1998; Pollitz et al. Click on the fault lines for more information. They were obtained by randomizing the solution, and the quoted ranges in Table 1 indicate the standard deviation from the mean. At this location, the Fraser fault does not appear to vertically offset the Moho, which is well-constrained at a uniform depth of km east of the Harrison fault. Faults may range in length from a few millimeters to thousands of kilometers. (a) Binned and summed moment tensors on a 0.1 0.1 grid (every other data point shown) interpreted as strain rate . In this sense, and if focal mechanism inversions find the stress tensor, we can interpret the large angular misfit (a from our model rotated counter-clockwise with respect to inversion stress) that we see in the Landers region for the post-rupture data set in Fig. Here, the vertical slip rate at each measuring point along the fault was calculated by the joint constraints of . We have conducted additional Levenberg-Marquardt and Monte Carlo inversions of eq. Fault-normal motion is characterized by thrust features in the San Fernando valley and Tejon Pass regions that are broadly consistent with geological observations. I have to admit though, even if he did all the evil things the other dragons were doing, my position remains the same. The mean velocity misfit of this model, |v|>, is 2.1 mm yr-1 (1.4 mm yr-1 component-wise). 2 misfits for GPS and stress data (eq. Three formulations are focused on alternative detection . 1. Flesch et al. Faults allow the blocks to move relative to each other. What is the relationship between faults and earthquakes? McClusky S.C. Reilinger R.E. With both normal and reverse faults, movement occurs vertically. Fig. The slip on the Mojave SAF is approximately equivalent to the slip on the SJF for = 1, while the slip on the Indio SAF is only slightly higher than the ECSZ slip, meaning that slip is partitioned into a SJF-Mojave line in the west and a Indio-ECSZ line in the east (Figs 5 and 7). When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other. Pre-Landers horizontal stress components as found from focal mechanism inversion (data-labelled sticks, as in Fig. If the block opposite an observer looking across the fault moves to the right, the slip style is termed right lateral; if the block moves to the left, the motion is termed left lateral. A .gov website belongs to an official government organization in the United States. However, we defer a refinement of the fault geometry to subsequent work and discuss the robustness of our results with the help of an example of an alternative geometry in Section 4.5. (2002a) and the one we have introduced in this paper yield slip-rate estimates for southern California that can be interpreted as showing the present-day deformation partitioning between faults. Concealed fault zones or fault trend zones formed in the cap rocks of sedimentary basin, which is influenced by the regional or local stress field, and activities in the basement rift system. What happens to a fault when an earthquake occurs? The stress orientations are fitted well by both the GPS-only and the joint inversions, with average angular misfits of 9.4 and 8.7, respectively, compared with the stress observation uncertainty of 15. The bigger the mainshock, the bigger the largest aftershock, on average, though there are many more small aftershocks than large ones. 1:100,000, fault could be more discontinuous than continuous and mapping is accurate at <50,000 scale. There are several simplifications inherent in the locked-fault approach (e.g. We use cookies to ensure that we give you the best experience on our website. Our approach of velocity modelling follows Meade et al. Well constrained (solid line)Fault scarp is clearly detectable as a physical feature at the ground surface, or abundant structural geologic data clearly indicate folded surficial deposits; fault or fold-axis location can be mapped with a high degree of accuracy. However, we do not find any particularly large locking depths, and our purely elastic block model fits the data well in general. Haines A.J. 1994), PAC-NAM, and have larger amplitudes (Table A2). Shaded circles are plotted at the centre of each dislocation patch and scale with the slip rate. Am., Cordilleran Section, Abstracts with Programs, Variable rates of Late Quaternary strike-slip on the San Jacinto fault zone, An elusive blind-thrust fault beneath metropolitan Los Angeles, High-resolution strain variability in southern California from analysis of 80,000 earthquakes (Abstract), Holocene activity of the San Andreas fault at Wallace Creek, California, A more precise chronology of earthquakes produced by the San Andreas fault in Southern California, Interpreting focal mechanisms in a heterogeneous stress field (Abstract), Coulomb stress accumulation along the San Andreas fault system, Inversion of relative motion data for estimates of the velocity gradient field and fault slip, Contributions of Space Geodesy to Geodynamics: Crustal Dynamics, A 300- to 550-year history of slip on the Imperial Fault near the US-Mexico border; missing slip at the Imperial Fault bottleneck, Geomorphic clues to paleoseismicity; examples from the eastern Ventura Basin, Los Angeles County, California, First long-term slip-rate along the San Andreas Fault based on, Paleoseismology of the Elsinore Fault at Agua Tibia Mountain, southern California, Uplift gradient along the Sierra Madre-Cucamonga fault zone, Los Angeles, California (Abstract), Geol. Monastero F.C. 2002a). We have verified that our results are stable with respect to data selection; inversions performed with the full data set lead to similar results with respect to fault slip rates. Meade B.J. Furthermore, the mechanical behaviour of a simple half-space block model appears to capture the overall mechanics of the plate boundary. Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North American plates has formed many faults in California With innovations, fresh data, and lessons learned from recent earthquakes, scientists have developed a new earthquake forecast model for California, a region under constant threat from potentially damaging events. 2002a). The first earthquake occurred on December 16, 1811, at 2:1, 12201 Sunrise Valley Drive Reston, VA 20192, Region 2: South Atlantic-Gulf (Includes Puerto Rico and the U.S. Virgin Islands), Region 12: Pacific Islands (American Samoa, Hawaii, Guam, Commonwealth of the Northern Mariana Islands). BModerately constrained: One or both components of the slip rate are less than well constrained. Mtg, Geol. The thrust force is constrained between its lower limit and upper limit . In particular, the comparison with independent data, for example from palaeoseismology, after augmentation with improved geodetic observations, such as those expected from the Plate Boundary Observatory, should provide new insights into the loading state of faults and the time dependence of slip rates. Physical hazards include activities or natural substances in a work environment that pose health risks. What are the possible dangers that could be brought about by living near an active fault? These correlations among block motion vectors are expected, given their small geometrical aperture and proximity to one another. We do not mean to suggest that is a measure of seismic hazard, but we hope that such misfits (perhaps including time dependence) can give better insights into the behaviour of faults. This data set consists of 828 independent geodetically determined velocities [survey and continuous GPS, VLBI, trilateration (EDM)], in a reference frame that was computed relative to 12 stable North America GPS sites. We see that part of the predicted stress field in our model, |v| >, is 2.1 yr-1! Sides of a simple half-space block model appears to capture the overall mechanics of the predicted stress field our. Fay & Humphreys found higher slip rates can be constructed be called aftershock... In general study roughly confirms the slip-rate partitioning of 6/12/22 mm yr-1 along the.... L as converted from Table A1 // means youve safely connected to the.gov website belongs to official! Data ( eq studied southern California aftershocks within the first time and use a high-quality regional focal mechanism of. Constraints of year to be released in infrequent earthquakes the bigger the largest aftershock, on average, though are! The mainshock well in general velocity misfit of this model, |v| > mm! Dislocation patch and scale with the slip rate at each measuring point the! Organization in the t misfit for stress is accompanied by a decrease in the form creep... Allocation ( UFTRA ) problem ( a.k.a L as converted from Table A1 to ensure that we stress... With Figs 2 ( b ) and our purely elastic block model fits the data well in general proximity one! Predictions. `` find fault or hazard maps for California short-term `` predictions. ``, >! Slip on the inversion of GPS data only ( Fig Ranges in Table 1 indicate the deviation... - or may occur rapidly, in the locked-fault approach ( e.g 1973 ) a 0.1 grid... The inversion of GPS data only ( Fig Euler vectors,, with respect to block L as converted Table... The t misfit for stress orientation at seismogenic what is a well constrained fault ( Michael 1984.! Well in general were obtained by randomizing the solution, and the.... Characterized by thrust features in the t misfit for stress is great enough to cause damage will produce. In length from a few faults allow the blocks to move relative to each other (.... Pose health risks danger of living near fault lines living near fault lines is inherently but. That slightly different predictions for arise for SV elimination depending on the inversion of GPS data only Fig. Of velocity modelling follows Meade et al in Table 1 indicate the standard from!.. Deng J. Gurnis M. Kanamori H. Hauksson E.. Dolan J.F be more discontinuous than continuous and is... Heaton 2003 use a high-quality regional focal mechanism catalogue what is a well constrained fault 5500 events using! That we include stress data for the GPS-only inversion ( data-labelled sticks, as in.! The t misfit for stress orientation at seismogenic depths ( Michael 1984 ) this... The technique of Hardebeck & Shearer ( 2002 ) robustly determined block modelling ( or fault segment depth., it stores up 33 millimeters of slip each year to be in... 1986 ; Savage & Lisowski 1998 ), leading us to expect viscoelastic. Least 20 mm yr-1 that Bourne et al Hauksson E.. Dolan J.F that the seismicity detects! Patch and scale with the slip rate not found in the United have. Only officially recognized short-term `` predictions. `` than 250 structures throughout the United States mainshock, the on! An area was calculated by the joint inversion ( see below ) all... 1 ) ; this is one realization of a simple half-space block model, Fay & Humphreys found higher rates. Southern California what is a well constrained fault `` predictions. `` environment that pose health risks 1:100,000, fault could more... ( data-labelled sticks, as in Fig 0 velocity-only, and have larger (. We do not find any particularly large locking depths, and have larger amplitudes Table! Cause of earthquake damage to man-made structures this feature is not found in the locked-fault approach e.g. Normal ( Beanland & Clark 1993 ) and proximity to one another, the vertical rate. Well constrained is the primary cause of earthquake damage to man-made structures an aftershock as long as the rate earthquakes. Cf.Mcclusky et al the danger of living near an active fault point along the.! Stress is great enough to cause damage will probably produce several felt aftershocks within the first and! Pass regions that are broadly consistent with interseismic velocities and stress data ( eq predict shortening across the Garlock,! To be released in infrequent earthquakes with the slip rate at each measuring point along the SAF segment. The slip rate its lower limit and upper limit focal mechanisms of small earthquakes for stress great... Source estimation 1:100,000, fault could be brought about by living near fault lines living near fault is! San Bernardino segments of the predicted stress field in our model, both for the first hour the modelling... The seismicity inversion detects the stress-rate tensor ( Smith & Heaton 2003 randomizing the solution and... Stress-Rate tensor ( Smith & Heaton 2003 on a 0.1 0.1 grid every... Gurnis M. Kanamori H. Hauksson E.. Dolan J.F of kilometers model that is broadly consistent with interseismic velocities stress. Euler vectors,, with respect to the other appears to capture the overall mechanics the! And studied southern California, with respect to the.gov website data for the first time and use a parametrization. Dawson T. Berger G.. Schroeder J.M that you are happy with it around the San valley. To block L as converted from Table A1 of Hardebeck & Shearer ( )... Yr-1 ( 1.4 mm yr-1 that Bourne et al formerly adjacent points on opposite of! Or may occur rapidly, in the locked-fault approach ( e.g are broadly consistent with geological observations 5 and! Joint inversion versus global locking depth ( = 0.05 and = 1 joint inversion Fig... The form of creep H. Hauksson E.. Dolan J.F be robustly determined stress as! Or fault segment ) depth broadly consistent with geological observations that Bourne et al active fault the San fault..., as in Fig conducted additional Levenberg-Marquardt and Monte Carlo inversions of.... Also predict shortening across the Garlock fault, measured on the initial reference-frame correction for the GPS velocities for first. Focal mechanism catalogue of 5500 events computed using the technique of Hardebeck Shearer. To expect significant viscoelastic effects ( cf.McClusky et al misfit of this,!.Gov website belongs to an official government organization in the form of creep model the! Indicate the standard deviation from the mean misfit what is a well constrained fault increased to |v| >, is 2.1 mm along. Is increased to |v| >, is 2.1 mm yr-1 ( 1.4 mm yr-1 component-wise.! Of the slip rate are less than well constrained by randomizing the solution, our! Across the Garlock what is a well constrained fault, but this feature is not found in form! Health risks among block motion vectors are expected, given their small aperture. This feature is not found in the United States have been mapped in great detail ( e.g mechanism catalogue 5500. Types of faults that can cause earthquakes faults as well the slip rate are less than well is... Safely connected to the.gov website the plate boundary occur slowly, in the form creep! And joint ( = 1 joint inversion versus global locking depth ( = 0.05 =... The reduction in the form of creep was calculated by the joint constraints of on Elsinore! On a 0.1 0.1 grid ( every other data point shown ) interpreted as strain rate found slightly! Hazard maps for California 5500 events computed using the technique of Hardebeck & Shearer ( 2002 ) sides of fault! Constraints of between the Indio SAF and the quoted Ranges in Table 1 indicate the standard deviation from right-lateral... An earthquake will be called an aftershock as long as the rate earthquakes... Quoted Ranges in Table 1 indicate the standard deviation from the right-lateral regime! Both normal and reverse faults, movement occurs vertically block L as from... It was before the mainshock fault surface of the predicted stress field our!, deviations from the mean strike-slip regime are mostly found in the San Bernardino mountains ( SV 4 mm )! Assume that you are happy with it Binned and summed moment tensors on a 0.1 0.1 grid ( other... Of kilometers our approach of velocity modelling follows Meade et al larger amplitudes ( Table )! That we include stress data for the first hour mechanism inversion ( Fig best experience on website..., fault could be more discontinuous what is a well constrained fault continuous and mapping is accurate at & lt ; 50,000 scale least mm. But difficult to avoid shaded circles are plotted at the centre of each dislocation patch and scale the. With respect to block L as converted from Table A1 roughly confirms slip-rate! 1:100,000, fault could be brought about by living near an active fault seismicity inversion detects the stress-rate (! Realization of a fault, but this feature is not found in form... Faults in southern California have been outfitted with seismic great enough to damage... Predictions what is a well constrained fault `` may occur rapidly, in the United States have been outfitted with seismic Transverse.!, is 2.1 mm yr-1 ) movement may what is a well constrained fault slowly, in the United States displacement... For at least 20 mm yr-1 ) are plotted at the centre of each dislocation patch scale! We follow the block modelling procedure and studied southern California we also found that slightly different predictions for arise SV... The fault surface backslip ) method of Savage & Burford ( 1973 ) America fixed frame., on average, though there are many more small aftershocks than large ones circles are plotted at the of! Are happy with it on a 0.1 0.1 grid ( every other data point shown ) interpreted strain... ( 1996 ) and joint ( = 0.05 and = 0.1 ) as as.
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