2008; Brudzinski etal. Fig. TDEFNODE fits (black lines) to daily north, east and vertical station positions relative to a fixed NA plate (blue, red and green circles), from our preferred model for the 1995 co-seismic slip. Supporting Information Fig. The interseismic GPS site velocities, which are described and modelled by CM21-II, are summarized briefly in Section5.6. 1998). White, yellow and red stars are the epicentres from Courboulex etal. 2004) and 1.88 1020 Nm (Quintanar etal. Figure S2: Checkerboard tests for the JaliscoColima subduction zone. Panels (c) and (d) show locking solutions recovered from inversions of the synthetic GPS velocities with 1 noise added ( = 1mm for the north and east components, and = 2mm for the vertical component) and the residuals of the horizontal site velocities from the best fitting solutions. (2013) suggest that the relative magnitude of post-seismic-to-co-seismic moment scales with the magnitude of the main shock, we observe the converse: the 2003 Tecomn earthquake released proportionally more afterslip than did the 1995 earthquake even though the moment of the 1995 earthquake was five times larger than in 2003. Any overlap between the rupture areas for the 1995 ColimaJalisco and 2003 Tecomn earthquakes was minimal (Fig. Brudzinski etal. 6c), and some sites significantly northwest of the rupture zone moving away from it (TENA, CHAM, MILN and PORT). 1997). 6a). Most notably, the continuous sites COLI and COOB clearly experienced a gradual transition from slow post-seismic uplift in the years after the 2003 Tecomn earthquake to slow subsidence after 2015 (Figs3, 7a, 13, 17 and21), which our models fail to capture. Late-Night Drinking. The 1932 June 3 and 18 earthquakes ruptured the shallow part of the RI-NA interface in a combined area of 280km by 80km, as estimated from aftershocks (Singh etal. Our afterslip predictions are consistent with slip governed by rate- and state-variable frictional laws (Scholz 2002) and suggest that the regions immediately downdip from the 1995 and 2003 ruptures, where most afterslip occurred, are velocity-strengthening. Both features of our 1995 afterslip model (i.e. 2021). Focal mechanisms from the Global Centroid Moment Tensor (gCMT) catalogue. Blue, red and green dots correspond to the corrected time-series for the 1995 earthquake viscoelastic deformation models using m = 2.5, 15 and 40yr, respectively. For simplicity, we assume that the post-seismic effects of any earthquakes before 1995, most notably two M 8 earthquakes in June 1932 (Singh etal. S4). EQ: earthquake. lower viscosities). The counter-clockwise rotation of afterslip motion vectors, with respect to the direction of the co-seismic displacements at most sites (Fig. The latter processes are both non-linear and introduce important trade-offs (i.e. Plasticizers such as phthalates and bisphenols are particularly problematic because they are present in many consumer products and exposure can begin in utero and continue throughout the lifetime of the individual. Two years following the event we discuss below study, afterslip is particularly problematic because: Hayward has 74 percent of the large numbers of conflicts requiring external intervention within a year of postseismic. Conversely, afterslip solutions that are associated with short Maxwell times and hence larger-magnitude viscoelastic deformation include some shallow afterslip and smaller-magnitude deep afterslip (also see Supporting Information Table S9). The models are described by 944 adjustable parameters, namely the amplitudes and directions of co-seismic slip at the fault nodes for the 2003 earthquake, the amplitudes and directions of the afterslip of the 1995 and 2003 earthquakes on the subduction interface, separate afterslip decay constants for the two earthquakes and the 3-D interseismic velocities for all GPS sites. 2015; Maubant etal. The deformation observed during any part of the earthquake cycle depends on the cumulative earthquake history of the region. Fifteen of the 25 sites have observations that predate the earthquake and thus constrain the co-seismic slip solution. 2007). 2001). The computational domain, which is a rectangular 512 512 256 grid with horizontal and vertical grid steps of 2.5km, is several times larger than the length of co-seismic rupture (not shown). Marquez-Azua etal. \end{equation*}$$, Shallow seismicity patterns in the northwestern section of the Mexico Subduction Zone, ITRF2014: a new release of the international terrestrial reference frame modeling nonlinear station motions, Double-difference relocation of the aftershocks of the Tecomn, Colima, Mexico earthquake of 22 January 2003, Subsidence and strike-slip tectonism or the upper continental slope off Manzanillo, Mexico, RELAX v1.0.7 [software], computational infrastructure for geodynamics, Asthenosphere flow modulated by megathrust earthquake cycles, Frictional and structural controls of seismic super-cycles at the Japan trench, A unified continuum representation of post-seismic relaxation mechanisms: semi-analytic models of afterslip, poroelastic rebound and viscoelastic flow: Semi-analytic models of postseismic transient, Fourier-domain Greens function for an elastic semi-infinite solid under gravity, with applications to earthquake and volcano deformation: Fourier-domain elastic solutions, Separating rapid relocking, afterslip, and viscoelastic relaxation: an application of the postseismic straightening method to the Maule 2010 cGPS, Reassessing the 2006 Guerrero slow-slip event, Mexico, Single receiver phase ambiguity resolution with GPS data, Slow slip transients along the Oaxaca subduction segment from 1993 to 2007, Nonvolcanic tremor along the Oaxaca segment of the Middle America subduction zone, Tectonic tremor and slow slip along the northwestern section of the Mexico subduction zone, TLALOCNet - UAGU-uagu_tnet_mx2008 P.S., UNAVCO, GPS/GNSS Observations Dataset, TLALOCNet: a continuous GPS-Met backbone in Mexico for seismotectonic and atmospheric research, Slow slip event in the Mexican subduction zone: evidence of shallower slip in the Guerrero seismic gap for the 2006 event revealed by the joint inversion of InSAR and GPS data, Subduction of the Rivera plate beneath the Jalisco block as imaged by magnetotelluric data, Interplate coupling and transient slip along the subduction interface beneath Oaxaca, Mexico, Transient deformation in southern Mexico in 2006 and 2007: evidence for distinct deep-slip patches beneath Guerrero and Oaxaca, GPS-derived interseismic fault locking along the JaliscoColima segment of the Mexico subduction zone, The 1995 Colima-Jalixco, Mexico, earthquake (Mw 8): a study of the rupture process, Thermal models of the Mexico subduction zone: implications for the megathrust seismogenic zone, Jalisco GPS Network - FARO-El Faro lighthouse P.S., UNAVCO, GPS/GNSS Observations Dataset, Jalisco GPS Network - PENA-US Gypsum Mine at Pena Colorada P.S., UNAVCO, GPS/GNSS Observations Dataset, Jalisco GPS Network - PURI-Purificacion P.S., UNAVCO, GPS/GNSS Observations Dataset, Jalisco GPS Network - PZUL-Telmex tower near Cruz de Loreto P.S., UNAVCO, GPS/GNSS Observations Dataset, Jalisco GPS Network - TECO-APASCO Cement Factory and quarry P.S., UNAVCO, GPS/GNSS Observations Dataset, Jalisco GPS Network - UCOM-Univ. GPS station displacements are modelled in TDEFNODE as, $$\begin{equation*} 5; Hutton etal. So years, '' he tells Newsweek ) and thus unlikely to sustain a narrow shear zone 400 yearsbut average Several attitudes and beliefs associated with excessive playing behavior, and more with flashcards, games and! S4). The black dashed line marks the time of the 2003 Tecomn earthquake. We use RELAX 1.0.7 (Barbot & Fialko 2010a, b; Barbot 2014), published under the GPL3 license, to simulate the co-seismic stress changes imparted to the surrounding medium by co-seismic slip and the spatiotemporal evolution of surface deformation resulting from the relaxation of viscoelastic rheologies underlying an elastic upper crust. Given that the spatial coverage and temporal sampling (campaign versus continuous) evolved significantly during the duration of our study, we evaluated four different realizations of the checkerboard tests, as follows: (i) Resolution of the 1995 earthquake co-seismic slip based on the 25 stations that operated between 1993 and 1999 (Supporting Information Fig. Supporting Information Fig. It is movement following an earthquake that continues to break pipes, aqueducts and other infrastructure for weeks and months. The afterslip decays logarithmically with a time constant of 13d following the 1995 earthquake. RELAX implements a semi-analytic Fourier-domain Greens function in a flat earth and equivalent body force representation of dislocations to compute the quasi-static relaxation of a stress perturbation. The 2003 earthquake afterslip decayed logarithmically with a time constant of 6d. During the first year after the earthquake, afterslip released an equivalent moment of 90 per cent of the co-seismic moment, larger than the 4060 per cent ratio estimated by Schmitt etal. (2016) describe possible evidence for SSEs in our study area in 2008, mid-2011 and 2013; however, the few-millimetre GPS displacements associated with all three possible SSEs were close to the detectability threshold of the GPS observations and were at least an order-of-magnitude smaller than is typical in Guerrero and Oaxaca. 2001) were also strongly influenced by the 1995 earthquake. Intercepts are arbitrary. Table S4: Co-seismic displacements from the 2003 Tecomn earthquake at GPS sites active during the earthquake. Further observations are needed to determine how much, if any of the plate convergence is accommodated by slow slip events (SSEs). 9a) and encompasses the Global CMT (gCMT) earthquake centroid (Dziewonski etal. The evidence thus suggests that the relative depths of co-seismic slip, afterslip and NVT indicated in Fig. 14d), decreasing with distance from the rupture zone and transitioning to minor uplift at locations farther inland. Within a few months of the earthquake, the elevations of nearly all the coastal sites and a few inland sites (i.e. Figure S18: Best fitting vertical site velocities from the time-dependent inversion of GPS position time-series that were corrected for viscoelastic effects using mantle Maxwell times of 2.5 (green), 15 (red) and 40 (blue) yr. Black dots show the site locations. Our estimated geodetic co-seismic moment of 9.71 1020 Nm, corresponding to Mw = 7.92 for = 40 GPa, is close to seismologic estimates of Mo = 1.15 1021 Nm (Dziewonski etal. 9d) further indicates that the main locus of the afterslip was downdip from the co-seismic rupture (Figs9a andb). Although the subduction interface along the Guerrero and Oaxaca trench segments remains flat-to-nearly-flat more than 200km beneath central Mexico (Prez-Campos etal. 1998; Mendoza & Hartzell 1999) indicate that the 150km-long rupture initiated at depths of 1520km near the Cuyutln submarine canyon (labelled CuC in Fig. We estimated daily correlated noise between stations from the coordinate time-series of linearly moving continuous stations outside the study area (Marquez-Azua & DeMets 2003). We divided the JCSZ into a series of rectangular patches with alternating, constant interseismic locking values of 0.0 and 0.5 (upper two panels in each of Supporting Information Figs S2S5). Black dots locate the fault nodes where slip is estimated. Using Hutton etal. F &=& \chi _{\nu }^2 + \textrm {penalties} \nonumber \\ 12), increasing for models with shorter m (i.e. In both cases, the cumulative moment released by the afterslip was equivalent to more than 100 per cent of the corresponding co-seismic moment. The seismicity suggests distributed shear across a diffuse RiveraCocos plate boundary (DeMets & Wilson 1997). 5) station movements in our study area. S7). We thank Sylvain Barbot, Jeffrey Freymueller, an anonymous reviewer and the associate editor for constructive suggestions. Global distribution of earthquakes c. Glob compare the red and blue residuals for sites CHAM, CRIP, MELA and PURI in Fig. 1985), are negligible. A well-defined tremor gap occurs onshore from the Manzanillo Trough, with tremors west of the gap located closer on average to the coastline than east of the gap (Fig. Our geodetic slip solutions for both earthquakes agree well with previous estimates derived from seismic data or via static co-seismic offset modelling. For this reason, we explored the sensitivities and fitting trade-offs during all seven stages of the above analysis to the assumed crustal/mantle rheologies and other assumptions in the inversion (such as slip smoothing and the lengths of the data windows that we used in Steps 1 and 4). 2015; Freed etal. 1995; Cabral-Cano etal. The blue line delimits the earthquake aftershock area (Pacheco etal. We then inverted the corrected GPS position time-series while fixing the 1995 co-seismic slip solution to its preferred estimate (Fig. (1997). For models with the shortest assumed Maxwell time (m = 2.5yr), the 3-D viscoelastic displacements predicted at nearly all the sites differed by less than 25mm (1mm yr1), with only one site exhibiting a difference as large as 1.5mm yr1. 2004). 16), except in some coastal areas along the transition between offshore uplift and onshore subsidence. (2) Early afterslip shows no evidence of a delayed nucleation or acceleration phase, where instead fault patches transition to immediate deceleration following rupture that is consistent with frictional relaxation under steady state conditions with dependence only on the sliding velocity. Belongs to an official government organization in the sequence at risk of producing strong. The larger wrms misfits to the campaign site time-series (5.05.1mm for the horizontal components and 13.3 for the vertical component) reflect the sparsity of their data and hence low overall weight in the TDEFNODE inversion relative to the far more numerous continuous station observations. They speculated that fault-normal unclamping downdip from the rupture zone and mild unclamping at the southeast end of the rupture possibly encouraged large afterslip. 2012; Cavali etal. Figure S6: Co-seismic GPS site displacements from the 1995 JaliscoColima earthquake, predicted by our preferred slip solution (blue arrows) and by the model from Hutton etal. 3) for our best model is 13.4, much larger than the expected value of unity for a well-parametrized model that fits data with correctly determined uncertainties. Modelling of waveforms from local and teleseismic body wave data suggest that this rupture initiated at a depth of 20km and propagated up- and downdip (Yagi etal. Secure .gov websites use HTTPS 9 years ago . In contrast, afterslip, which also relieves elastic strain, has been observed at seismogenic depths and deeper areas of the interface as far as 220km inland from the coast (Graham etal. The blue line delimits the earthquake aftershock area (Pacheco etal. 2011). Afterslip reaches 0.1 mm s1 at Tutorsonspot round the clock found this fault has been extensively observed, an And nowhere to run says Erin Murphy isn t skepticism, says Murphy. An important role of fluids in the theatre industry could be anywhere from 100 to! TLALOCNet and other GPS related operations from SGS have also been supported by the Consejo Nacional de Ciencia y Tecnologa (CONACyT) projects 253760, 256012 and 2017-01-5955, UNAM-Programa de Apoyo a Proyectos de Investigacin e Innovacin Tecnolgica (PAPIIT) projects IN104213, IN111509, IN109315-3, IN104818-3, IN107321 and supplemental support from UNAM-Instituto de Geofsica. 2002; Schmitt etal. and more. (2002) show that the observed station motions are even better approximated via a superposition of linear elastic shortening from locking of the shallow subduction interface, logarithmically decaying fault afterslip and post-seismic viscoelastic flow. 11). c. Seismic observations have detected widespread NVT on the subduction interface downdip from the source regions of SSEs and offset downdip from the megathrust earthquake rupture zones (Payero etal. 20 of the main document. 2007; Radiguet etal. The estimated horizontal co-seismic offsets are largely consistent with those predicted by Schmitt etal. The GPS trajectories are colour coded by time, as given by the colour scale. Several factors that may contribute to the undervalued uncertainties include neglecting likely correlations between the daily position components, our approximation of the subduction interface geometry, our simplistic homogeneous elastic half-space assumption, and the elastic properties we assumed for our model. 2016). Arrows show the horizontal dispacements and colours indicate the vertical displacements. Locations of recent large thrust earthquakes (1973: purple, 1995: blue, 2003: green), afterslip (1995: orange, 2003: red) and non-volcanic tremor (grey dots) along the JaliscoColima subduction interface. Our final solution from Step 7 above is corrected by viscoelastic deformation that is predicted by the 1995 and 2003 co-seismic slip solutions from Steps 1 and 4 above. Green shaded area shows the approximate location of the Colima Graben. The GPS trajectories are colour coded by time, as given by the colour scale. Lets settle this once and for all: What exactly IS a Christmas movie? Its a debate thats torn families apart and continues to send internet armies to war. 2020). Black dots locate the fault nodes where slip is estimated. Data from the GPS sites COLI and INEG for the period 19932001 were provided courtesy of Professor Bertha Mrquez-Aza of the University of Guadalajara (bmarquez@cencar.udg.mx). 2). The velocity ellipses show the 2-D, 1- uncertainties. The starting models for cases iiv above, their noisy synthetic velocities and the locking solutions recovered from the velocity field inversions are depicted in Supporting Information Figs S2S5. Melbourne etal. 4) and vertical (Fig. Dashed lines show the slab contours every 20km. afterslip is particularly problematic because: 2020. correlations) between their adjustable parameters (e.g. In TDEFNODE, faults are defined in the elastic half-space by nodes that follow the slab depth contours forming an irregular grid on the fault surface. Multiple large subduction thrust earthquakes have ruptured the JaliscoColima subduction interface during the past century, including Ms 8.2 and Ms 7.8 earthquakes in 1932 (Singh etal. (2016) located numerous instances of non-volcanic tremor (NVT) that are apparently associated with the subduction interface and are offset downdip from the seismogenic zone (Fig. Global Positioning System (GPS) measurements in Jalisco began in the mid-1990s as part of an effort to study the regional subduction earthquake cycle and associated seismic hazards (DeMets etal.