{"id":10727,"date":"2023-01-08T22:43:00","date_gmt":"2023-01-08T22:43:00","guid":{"rendered":"https:\/\/earthjay.com\/?p=10727"},"modified":"2023-12-30T20:49:10","modified_gmt":"2023-12-30T20:49:10","slug":"earthquake-report-m-7-0-vanuatu","status":"publish","type":"post","link":"https:\/\/earthjay.com\/?p=10727","title":{"rendered":"Earthquake Report: M 7.0 Vanuatu"},"content":{"rendered":"<p>Early this morning (my time) I got a notification from the Pacific Tsunami Warning Center that there was no tsunami threat from an M 7.2 earthquake in the Vanuatu Islands.<\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"tl\" dir=\"ltr\">Tsunami Info Stmt: M7.2 Vanuatu Islands 0433PST Jan 8: Tsunami NOT expected; CA,OR,WA,BC,and AK<\/p>\n<p> <a href=\"https:\/\/twitter.com\/hashtag\/NTWC?src=hash&amp;ref_src=twsrc%5Etfw\">#NTWC<\/a><\/p>\n<p>&mdash; NWS Tsunami Alerts (@NWS_NTWC) <a href=\"https:\/\/twitter.com\/NWS_NTWC\/status\/1612067216614383618?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<p>Later, as I woke up I checked the USGS website to see that there was an M7.0 earthquake offshore of the Vanuatu Islands. <\/p>\n<p><a href=\"https:\/\/earthquake.usgs.gov\/earthquakes\/eventpage\/us7000j2yw\/executive\" rel=\"noopener\" target=\"_blank\">https:\/\/earthquake.usgs.gov\/earthquakes\/eventpage\/us7000j2yw\/executive<\/a><\/p>\n<p>Based on the depth of the hypocenter (the 3-D location of the earthquake) it appears that this M 7.0 ruptured a thrust fault within the Australia plate. Given the uncertainty of the location of the megathrust fault, it is possible that this actually was on the megathrust subduction zone fault (so is what we call an &#8220;interface&#8221; event). I don&#8217;t think that the USGS finite fault model is correct (it seems unlikely that this earthquake ruptured a fault within the Australia plate and slipped up into the upper plate). But I could be wrong (which is quite common). <\/p>\n<p>I don\u2019t always have the time to write a proper Earthquake Report. However, I prepare interpretive posters for these events.<\/p>\n<p>Because of this, I present Earthquake Report Lite. (but it is more than just water, like the adult beverage that claims otherwise). I will try to describe the figures included in the poster, but sometimes I will simply post the poster here. (UPDATE: I could not resist spending a little time looking at updated papers from this region, so have included some figures below.)<\/p>\n<p><H2><font color=\"orange\">Below is my interpretive poster for this earthquake<\/font><\/H2><\/p>\n<ul>\n<li>I plot the seismicity from the past month, with diameter representing magnitude (see legend). I include earthquake epicenters from 1921-2021 with magnitudes M \u2265 3.0 in one version. <\/li>\n<li>I plot the USGS fault plane solutions (moment tensors in blue and focal mechanisms in orange), possibly in addition to some relevant historic earthquakes. <\/li>\n<li>A review of the basic base map variations and data that I use for the interpretive posters can be found on the <a href=\"http:\/\/earthjay.com\/?page_id=3218\" rel=\"noopener\" target=\"_blank\">Earthquake Reports page<\/a>. I have improved these posters over time and some of this background information applies to the older posters.<\/li>\n<li>Some basic fundamentals of earthquake geology and plate tectonics can be found on the <a href=\"http:\/\/earthjay.com\/?page_id=8202\" rel=\"noopener noreferrer\" target=\"_blank\">Earthquake Plate Tectonic Fundamentals page<\/a>.<\/li>\n<\/ul>\n<ul>\n<H3><font color=\"orange\">I include some inset figures. <\/font><\/H3><\/p>\n<\/ul>\n<ul>\n<li>Here is the map with 3 month&#8217;s seismicity plotted.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/20230108_vanuatu_interpretation.pdf\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/20230108_vanuatu_interpretation.jpg\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<\/ul>\n<p><H2><font color=\"orange\">Some Supporting Information<\/font><\/H2><\/p>\n<ul>\n<li>Here is the USGS poster showing the seismicity for this region from 1900-2010 (<a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec.pdf\" target=\"_blank\" rel=\"noopener\">Benz et al., 2011<\/a>). Below I include the legend (not the correct scale; <a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec.pdf\" target=\"_blank\" rel=\"noopener\">click on this link for the entire poster<\/a> (65 MB pdf)). Note the cross section F-F&#8217; which I plot on the poster above.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_map_new_hebrides.PNG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_map_new_hebrides.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_map_legend.PNG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_map_legend.PNG\" alt=\"\" \/><\/a><\/p>\n<li>Here is the cross section F-F&#8217; again, with the legend below.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_xsec_FF.PNG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_xsec_FF.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_xsec_legend.PNG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/benz_etal_2011_seismicity_earth_new_hebrides_tonga_kermadec_xsec_legend.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<\/ul>\n<ul>\n<li>Here are some figures from Bergeot et al., 2009.<\/li>\n<li>This first figure shows the tectonic setting and the plate convergence rates (the rates, in mm\/year, that the Australia plate is converging relative to the North Fiji Basin.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_02.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_02.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\n(a) Geodynamic setting of the VSZ, with block motions relative to the North Fiji Basin [from Calmant et al., 2003]. The Vanuatu arc is split into three blocks, with anticlockwise rotation (north), convergence (center), and clockwise rotation (south). Dashed line is the BATB; solid lines are the spreading ridge; bold line is the VSZ. Bathymetry data are from Calmant et al. [2002]. The black rectangle is the central part of the Vanuatu arc. White arrows are velocities (millimeters per year) with respect to the Australian plate (AP); black arrows are block motion with respect to the North Fiji Basin. Dotted line is the cross section of Figure 2b. (b) Schematic of the central part of the VSZ [from Lagabrielle et al., 2003]. The direction of this cross section is west to east, and it intersects the Santo and Maewo Islands (dotted line in Figure 2a). Abbreviations are as follows: IAB, Aoba Intra-arc Basin; BATB, back-arc thrust belt; NFB, North Fiji Basin.\n<\/p><\/blockquote>\n<li>This figure shows the horizontal motion rates (in mm\/year) for the GPS sites in the region.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_06.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_06.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nHorizontal interseismic GPS velocities for the VSZ in an Australia-fixed reference frame. The Australian motion is estimated as a rigid rotation from our GPS results with a least squares inversion. Abbreviations are as follows: WTP, West Torres Plateau; DER, D\u2019Entrecasteaux Ridge. Lines are (1) BATB, (2) spreading ridge, (3) VSZ, (4) discontinuity supposed between TGOA and Epi island, and (5) transition zone.\n<\/p><\/blockquote>\n<li>This figure shows a map where they plot, in the next figure, a comparison between their modeled vertical velocities with the observed vertical velocities.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_11.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_11.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nTransects and GPS stations used to assess the locked zone parameters in this study. Shaded triangles represent the A-A0 (TNMR, LVMP, LMBU, WLRN, SWBY, VMVS, NSUP, RNSR, and AMBR) transect GPS stations, and solid triangles represent the B-B0 transect GPS stations (LISB, TASM, AVNA, RATA, RATU, SANC, AOBA, PNCT, and MAWO). The bold lines represent the A-A0 and B-B0 transects. The white arrows show the convergence direction. Abbreviations are as follows: DER, D\u2019Entrecasteaux Ridge; WTP, Wet Torres Plateau. The stars indicate the edge of the locked zone as deduced from the GPS velocity interpretation (Figure 12). Lines are (1) BATB and (2) VSZ.\n<\/p><\/blockquote>\n<li>This figure shows the comparison between their modeled velocities and the observed velocities.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_12.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/bergeot_etal_2009_gps_velocity_field_vanuatu_fig_12.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\n(top) Vertical and (bottom) horizontal (perpendicular to the trench) velocity profiles for the GPS stations of the A-A0 (open circle) and B-B0 (filled circle) transects. Distances are given with respect to the trench. The bold curves represent the best fit of the locked zone and long-term convergence rate model (dip, 20\u0001; width, 50 km; slip, 54 mm a\u00011) estimated from observed velocities. Lines 2 and 3 represent the effect of the width variation in the model (45 and 60 km, respectively). See Figure 11 for the transect location.\n<\/p><\/blockquote>\n<\/ul>\n<ul>\n<li>Here are the two figures from Cleveland et al. (2014).<\/li>\n<li>Figure 1. I include the figure caption below as a blockquote.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_01.JPG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_01.JPG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\n(left) Seismicity of the northern Vanuatu subduction zone, displaying all USGS-NEIC earthquake hypocenters since 1973. The Australian plate subducts beneath the Pacific in nearly trench-orthogonal convergence along the Vanuatu subduction zone. The largest events are displayed with dotted outlines of the magnitude-scaled circle. Convergence rates are calculated using the MORVEL model for Australia Plate relative to Pacific Plate [DeMets et al., 2010]. (right) All GCMT moment tensor solutions and centroids for Mw \u2265 5 since 1976, scaled with moment. This region experiences abundant moderate and large earthquakes but lacks any events with Mw >8 since at least 1900.\n<\/p><\/blockquote>\n<li>Figure 17. I include the figure caption below as a blockquote.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_02.JPG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_02.JPG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nOne hundred day aftershock distributions of all earthquakes listed in the ISC catalog for the 1966 sequence and in the USGS-NEIC catalog for the 1980, 1997, 2009, and 2013 sequences in northern Vanuatu. The 1966 main shocks are plotted at locations listed by Tajima et al. [1990]. Events of the 1997 and 2009 sequences were relocated using the double difference method [Waldhauser and Ellsworth, 2000] for P wave first arrivals based on EDR picks. The event symbol areas are scaled relative to the earthquake magnitudes based on a method developed by Utsu and Seki [1954]. Hypocenters of most aftershock events occurred at <50 km depth.\n<\/p><\/blockquote>\n<li>Figure 17. I include the figure caption below as a blockquote.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_17.JPG\" target=\"_blank\" rel=\"noopener\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20170509_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu_fig_17.JPG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\n(right) Space-time plot of shallow (\u2264 70 km) seismicity M \u2265 5.0 in northern Vanuatu recorded in the NEIC catalog as a function of distance south of ~10\u00b0N, 165.25\u00b0E. (left) The location of the seismicity on a map rotated to orient the trench vertically.\n<\/p><\/blockquote>\n<\/ul>\n<ul>\n<li>Craig et al. (2014) evaluated the historic record of seismicity for subduction zones globally. In particular, the evaluated the relations between upper and lower plate stresses and earthquake types (cogent for the southern New Hebrides trench). Below is a figure from their paper for this part of the world. I include their figure caption below in blockquote.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20171119_loyalty_islands\/craig_etal_2014_reassessment_outer_rise_seismicity_fig_08.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20171119_loyalty_islands\/craig_etal_2014_reassessment_outer_rise_seismicity_fig_08.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nOuter-rise seismicity along the New Hebrides arc. (a) Seismicity and focal mechanisms. Seismicity at the southern end of the arc is dominated by two major outer-rise normal faulting events, and MW 7.6 on 1995 May 16 and an MW 7.1 on 2004 January 3. Earthquakes are included from Chapple &#038; Forsyth (1979); Chinn &#038; Isacks (1983); Liu &#038; McNally (1993). (b) Time versus latitude plot.\n<\/p><\/blockquote>\n<\/ul>\n<ul>\n<li>Here is a summary figure from Craig et al. (2014) that shows different stress configurations possibly existing along subduction zones.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20171119_loyalty_islands\/craig_etal_2014_reassessment_outer_rise_seismicity_fig_16.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20171119_loyalty_islands\/craig_etal_2014_reassessment_outer_rise_seismicity_fig_16.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nSchematic diagram for the factors influencing the depth of the transition from horizontal extension to horizontal compression beneath the outer rise. Slab pull, the interaction of the descending slab with the 660 km discontinuity (or increasing drag from the surround mantle), and variations in the interface stress influence both the bending moment and the in-plane stress. Increases in the angle of slab dip increases the dominance of the bending moment relative to the in-plane stress, and hence moves the depth of transition towards the middle of the mechanical plate from either an shallower or a deeper position. A decrease in slab dip enhances the influence of the in-plane stress, and hence moves the transition further from the middle of the mechanical plate, either deeper for an extensional in-plane stress, or shallower for a compressional in-plane stress. Increased plate age of the incoming plate leads to increases in the magnitude of ridge push and intraplate thermal contraction, increasing the in-plane compressional stress in the plate prior to bending. Dynamic topography of the oceanic plate seawards of the trench can result in either in-plane extension or compression prior to the application of the bending stresses.\n<\/p><\/blockquote>\n<\/ul>\n<ul>\n<li>Here are the figures from Richards et al. (2011) with their figure captions below in blockquote.<\/li>\n<li>Here is the map showing the current configuration of the slabs in the region.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_02.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_02.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nMap showing distribution of slab segments beneath the Tonga-Vanuatu region. West-dipping Pacifi c slab is shown in gray; northeast-dipping Australian slab is shown in red. Three detached segments of Australian slab lie below the North Fiji Basin (NFB). HFZ\u2014Hunter Fracture Zone. Contour interval is 100 km. Detached segments of Australian plate form sub-horizontal sheets located at ~600 km depth. White dashed line shows outline of the subducted slab fragments when reconstructed from 660 km depth to the surface. When all subducted components are brought to the surface, the geometry closely approximates that of the North Fiji Basin.\n<\/p><\/blockquote>\n<li>This is the cross section showing the megathrust fault configuration based on seismic tomography and seismicity.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_03.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_03.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nPrevious interpretation of combined P-wave tomography and seismicity from van der Hilst (1995). Earthquake hypocenters are shown in blue. The previous interpretation of slab structure is contained within the black dashed lines. Solid red lines mark the surface of the Pacifi c slab (1), the still attached subducting Australian slab (2a), and the detached segment of the Australian plate (2b). UM\u2014upper mantle;<br \/>\nTZ\u2014transition zone; LM\u2014lower mantle.\n<\/p><\/blockquote>\n<li>Here is their time step interpretation of the slabs that resulted in the second figure above.<\/li>\n<p><a href=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_04.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"http:\/\/earthjay.com\/earthquakes\/20171031_new_caledonia\/richards_etal_2011_when_arcs_collide_fig_04.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nSimplifi ed plate tectonic reconstruction showing the progressive geometric evolution of the Vanuatu and Tonga subduction systems in plan view and in cross section. Initiation of the Vanuatu subduction system begins by 10 Ma. Initial detachment of the basal part of the Australian slab begins at ca. 5\u20134 Ma and then sinking and collision between the detached segment and the Pacifi c slab occur by 3\u20134 Ma. Initial opening of the Lau backarc also occurred at this time. Between 3 Ma and the present, both slabs have been sinking progressively to their current position. VT\u2014Vitiaz trench; dER\u2014d\u2019Entrecasteaux Ridge.\n<\/p><\/blockquote>\n<li>Here are two great figures from Deng et al. (2022). This article focuses on the influence of the D&#8217;Entrecasteaux Ridge on subduction here in Vanuatu. They focus on geochemical data from magmatic rocks in the area.<\/li>\n<li>This one shows a variety of processes going on in this area.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/deng_etal_2022_influence_suduction_vanuatu_fig_01.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/deng_etal_2022_influence_suduction_vanuatu_fig_01.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nGeological and geophysical constraints regarding the evolution of the Vanuatu arc. (a) Bathymetric map showing the locations of islands for which samples were included in our geochemical compilation. Slab dip contours below the Vanuatu arc are displayed every 20\u00b0 (from Hayes et al., 2018). (b) Bathymetric map of the Vanuatu arc and an inset showing depth-to-slab versus distance-from-trench for each of the sample localities included in our compilation (Table S1 in Supporting Information S1). Slab depth contours beneath the Vanuatu arc are displayed every 20 km (from Hayes et al., 2018). The orange lines show the chosen cross sections (i.e., Sections A, B, C) across the different blocks of the Vanuatu arc, which were used to estimate slab dips. Orange dots denote the location of Deep Sea Drilling Project Site 286 and Ocean Drilling Program Legs 134 Sites 828 and 831. (c) Interpreted geodynamic setting of the Vanuatu arc based on modern global positioning system velocity measurements (observed, black arrows; modeled, white arrows; from Bergeot et al., 2009). The Vanuatu arc can be divided into three tectonic blocks that are separated by two strike-slip faults (magenta dashed lines; Calmant et al., 2003; Taylor et al., 1995), which are the counterclockwise rotated Northern Block, the eastward migrated Central Block and the clockwise rotated Southern Block. Orange arrows indicate plate convergence velocities (in mm\/year) with respect to the Australian plate (Bergeot et al., 2009). (d) Intermediate-depth seismicity distribution (50\u2013170 km) since 1972 with magnitudes in the range of 4\u20137, from USGS Earthquake Catalog (https:\/\/earthquake.usgs.gov\/earthquakes\/search\/). The seismic gap is highlighted by a solid polygon. The wide red arrow depicts the influx of hot sub-slab mantle to the forearc mantle wedge through a slab tear.\n<\/p><\/blockquote>\n<li><\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/deng_etal_2022_influence_suduction_vanuatu_fig_08.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/deng_etal_2022_influence_suduction_vanuatu_fig_08.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nSchematic of the Vanuatu subduction zone to illustrate the model proposed by this study. The conceptual model highlights the role that the subducting buoyant D\u2019Entrecasteaux ridge plays in the dynamic evolution of the Vanuatu arc. The introduction of D\u2019Entrecasteauz Ridge causes shallow subduction and the development of a slab tear south of the ridge and the segmentation of the Vanuatu arc into the Northern Block, Central Block and Southern Block. Shallow slab subduction beneath the Central Block results in (a) squeezing out of the asthenospheric mantle; (b) scraping off the bottom of the ancient continental lithospheric mantle beneath the forearc, which then migrates ahead of the advancing slab and forms a bulldozed keel underneath the main-arc and (c) transmitting compressional stresses in the over-riding plate, which inhibits the formation of backarc spreading and instead produces a backarc thrust belt. Additionally, the ingression of hot subslab mantle causes partial melting of the cold forearc mantle and produces magmatism anomalously close to the trench (i.e., the Efate, Nguna, and Pele volcanoes that are situated in the forearc).\n<\/p><\/blockquote>\n<li>Here is a video that shows a simulation from Deng et al. (2022).<\/li>\n<p><iframe loading=\"lazy\" width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/g4AzXBgKZ1E\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen><\/iframe><\/p>\n<ul>\n<li>Baillard et al. (2015) provide some insight into the geometry of the Australia plate slab. I am adjusting my hypothesis to be that this M 7.0 probably was on the megathrust, based on their work.<\/li>\n<li>This first figure shows a map and some cross sections.<\/li>\n<li>Note how cross section 4 is really close to the M 7.0. This geometry places the top of the slab below the M 7.0 hypocenter.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_06.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_06.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nGeometry of the subduction interface and updip\/downdip extents of the seismogenic zone. (a) Map view. The green contour is at 27 km depth and marks the intersection with the fore-arc Moho. The dashed contours present the updip and downdip extents of the seismogenic zone. The numbered lines showthe location of cross sections plotted to the right. NDR: north d\u2019Entrecasteaux ridge; BS: Bougainville seamount. (b) Geometric cross sections of the subduction interface (depth as a function of distance from the subduction front). (c) Dip cross sections (dip angle as a function of distance from the subduction front).\n<\/p><\/blockquote>\n<li>This figure shows how they interpret the seismicity in this area.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_08.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_08.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nCross section of seismic activity through the center of our total catalog (only events with residuals <0.2 s are plotted). Three clusters of activity are observed: (1) around the subduction interface (green), (2) within the subducting plate beneath the subduction interface (red), and (3) at intermediate depths (blue). The dotted line is our interpretation of the subduction interface.\n<\/p><\/blockquote>\n<li>This figure shows some specific earthquakes they used in their analyses. Earthquake 1 (pink) is really close to the M 7.0. They interpret that event to be in the upper part of the Australia plate. At this point, I suggest that it is equivocal, about whether or not the M 7.0 was an interface event or a slab or crustal event.<\/li>\n<p><a href=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_09.PNG\" rel=\"noopener\" target=\"_blank\"><br \/>\n<img decoding=\"async\" src=\"https:\/\/earthjay.com\/earthquakes\/20230108_vanuatu\/baillard_etal_2015_Seismicity_shallow_slab_geometry_Vanuatu_fig_09.PNG\" width=\"100%\" alt=\"\" \/><\/a><\/p>\n<blockquote><p>\nClusters and focal mechanisms in the local catalog. Simple focal mechanisms are illustrated in black, composite focal mechanisms in colors corresponding to the cluster events (circles). P axes indicated in red. (a) Map view. The boxes indicate the orientation and dimensions of the cross sections. (b) Cross section beneath Santo Island. (c) Cross section between Santo and Malekula Islands. The cross sections also show the picked subduction interface (thick black curve), the Australian Plate Moho (dotted line, assuming a 8 km thick crust), and the North Fiji Basin Moho (dotted line, assuming a 27 km thick fore-arc crust).\n<\/p><\/blockquote>\n<\/ul>\n<\/ul>\n<ul>\n<h2> <strong><font color=orange>New Britain | Solomon | Bougainville | New Hebrides | Tonga | Kermadec Earthquake Reports<\/font><\/strong> <\/h2>\n<h3>General Overview<\/h3>\n<h3>Earthquake Reports<\/h3>\n<li>2023.01.08 <a href=\"https:\/\/earthjay.com\/?p=10727\">M 7.0 Vanuatu Islands<\/a> (poster)<\/li>\n<li>2022.11.22 <a href=\"https:\/\/earthjay.com\/?p=10586\">M 7.0 Solomon Isles<\/a><\/li>\n<li>2022.11.11 <a href=\"https:\/\/earthjay.com\/?p=10493\">M 7.3 Tonga<\/a><\/li>\n<li>2022.09.10<a href=\"https:\/\/earthjay.com\/?p=10415\"> M 7.6 Papua New Guinea<\/a><\/li>\n<li>2021.03.04 <a href=\"https:\/\/earthjay.com\/?p=9955\">M 8.1 Kermadec<\/a><\/li>\n<li>2021.02.10 <a href=\"https:\/\/earthjay.com\/?p=9988\">M 7.7 Loyalty Islands<\/a><\/li>\n<li>2019.06.15 <a href=\"https:\/\/earthjay.com\/?p=8598\">M 7.2 Kermadec<\/a><\/li>\n<li>2019.05.14 <a href=\"https:\/\/earthjay.com\/?p=8528\">M 7.5 New Ireland<\/a><\/li>\n<li>2019.05.06 <a href=\"https:\/\/earthjay.com\/?p=8487\">M 7.2 Papua New Guinea<\/a><\/li>\n<li>2018.12.05 <a href=\"https:\/\/earthjay.com\/?p=8036\">M 7.5 New Caledonia<\/a><\/li>\n<li>2018.10.10 <a href=\"https:\/\/earthjay.com\/?p=7839\">M 7.0 New Britain, PNG<\/a><\/li>\n<li>2018.09.09 <a href=\"https:\/\/earthjay.com\/?p=7777\">M 6.9 Kermadec<\/a><\/li>\n<li>2018.08.29 <a href=\"https:\/\/earthjay.com\/?p=7703\">M 7.1 Loyalty Islands<\/a><\/li>\n<li>2018.08.18 <a href=\"https:\/\/earthjay.com\/?p=7598\">M 8.2 Fiji<\/a><\/li>\n<li>2018.03.26 <a href=\"https:\/\/earthjay.com\/?p=7289\">M 6.9 New Britain<\/a><\/li>\n<li>2018.03.26 <a href=\"https:\/\/earthjay.com\/?p=7274\">M 6.6 New Britain<\/a><\/li>\n<li>2018.03.08 <a href=\"https:\/\/earthjay.com\/?p=7225\">M 6.8 New Ireland<\/a><\/li>\n<li>2018.02.25 <a href=\"https:\/\/earthjay.com\/?p=7157\">M 7.5 Papua New Guinea<\/a><\/li>\n<li>2018.02.26 <a href=\"https:\/\/earthjay.com\/?p=7193\">M 7.5 Papua New Guinea Update #1<\/a><\/li>\n<li>2017.11.19 <a href=\"https:\/\/earthjay.com\/?p=5956\">M 7.0 Loyalty Islands Update #1<\/a><\/li>\n<li>2017.11.07 <a href=\"https:\/\/earthjay.com\/?p=5941\">M 6.5 Papua New Guinea<\/a><\/li>\n<li>2017.11.04 <a href=\"https:\/\/earthjay.com\/?p=5926\">M 6.8 Tonga<\/a><\/li>\n<li>2017.10.31 <a href=\"https:\/\/earthjay.com\/?p=5918\">M 6.8 Loyalty Islands<\/a><\/li>\n<li>2017.08.27 <a href=\"https:\/\/earthjay.com\/?p=5765\">M 6.4 N. Bismarck plate<\/a><\/li>\n<li>2017.05.09 <a href=\"https:\/\/earthjay.com\/?p=5359\">M 6.8 Vanuatu<\/a><\/li>\n<li>2017.03.19 <a href=\"https:\/\/earthjay.com\/?p=5182\">M 6.0 Solomon Islands<\/a><\/li>\n<li>2017.03.05 <a href=\"https:\/\/earthjay.com\/?p=5142\">M 6.5 New Britain<\/a><\/li>\n<li>2017.01.22 <a href=\"https:\/\/earthjay.com\/?p=4946\">M 7.9 Bougainville<\/a><\/li>\n<li>2017.01.03 <a href=\"https:\/\/earthjay.com\/?p=4761\">M 6.9 Fiji<\/a><\/li>\n<li>2016.12.17 <a href=\"https:\/\/earthjay.com\/?p=4596\">M 7.9 Bougainville<\/a><\/li>\n<li>2016.12.08 <a href=\"https:\/\/earthjay.com\/?p=4580\">M 7.8 Solomons<\/a><\/li>\n<li>2016.10.17 <a href=\"https:\/\/earthjay.com\/?p=4362\">M 6.9 New Britain<\/a><\/li>\n<li>2016.10.15 <a href=\"https:\/\/earthjay.com\/?p=4346\">M 6.4 South Bismarck Sea<\/a><\/li>\n<li>2016.09.14 <a href=\"https:\/\/earthjay.com\/?p=4314\">M 6.0 Solomon Islands<\/a><\/li>\n<li>2016.08.31 <a href=\"https:\/\/earthjay.com\/?p=4260\">M 6.7 New Britain<\/a><\/li>\n<li>2016.08.12 <a href=\"https:\/\/earthjay.com\/?p=4198\">M 7.2 New Hebrides Update #2<\/a><\/li>\n<li>2016.08.12 <a href=\"https:\/\/earthjay.com\/?p=4189\">M 7.2 New Hebrides Update #1<\/a><\/li>\n<li>2016.08.12 <a href=\"https:\/\/earthjay.com\/?p=4180\">M 7.2 New Hebrides<\/a><\/li>\n<li>2016.04.06 <a href=\"https:\/\/earthjay.com\/?p=3919\">M 6.9 Vanuatu Update #1<\/a><\/li>\n<li>2016.04.03 <a href=\"https:\/\/earthjay.com\/?p=3887\">M 6.9 Vanuatu<\/a><\/li>\n<li>2015.03.30 <a href=\"https:\/\/earthjay.com\/?p=2310\">M 7.5 New Britain<\/a> (Update #5)<\/li>\n<li>2015.03.30 <a href=\"https:\/\/earthjay.com\/?p=2306\">M 7.5 New Britain<\/a> (Update #4)<\/li>\n<li>2015.03.29 <a href=\"https:\/\/earthjay.com\/?p=2303\">M 7.5 New Britain<\/a> (Update #3)<\/li>\n<li>2015.03.29 <a href=\"https:\/\/earthjay.com\/?p=2298\">M 7.5 New Britain<\/a> (Update #2)<\/li>\n<li>2015.03.29 <a href=\"https:\/\/earthjay.com\/?p=2289\">M 7.5 New Britain<\/a> (Update #1)<\/li>\n<li>2015.03.29 <a href=\"https:\/\/earthjay.com\/?p=2287\">M 7.5 New Britain<\/a> <\/li>\n<li>2015.11.18 <a href=\"https:\/\/earthjay.com\/?p=3315\">M 6.8 Solomon Islands<\/a><\/li>\n<li>2015.05.24 <a href=\"https:\/\/earthjay.com\/?p=2519\">M 6.8, 6.8, 6.9 Santa Cruz Islands<\/a><\/li>\n<li>2015.05.05 <a href=\"https:\/\/earthjay.com\/?p=2424\">M 7.5 New Britain<\/a><\/li>\n<\/ul>\n<\/ul>\n<ul>\n<H2><strong><font color=\"orange\">References:<\/font><\/strong><\/H2><\/p>\n<p><H3>Basic &#038; General References<\/H3><\/p>\n<li>Frisch, W., Meschede, M., Blakey, R., 2011. Plate Tectonics, Springer-Verlag, London, 213 pp.<\/li>\n<li>Hayes, G., 2018, Slab2 &#8211; A Comprehensive Subduction Zone Geometry Model: U.S. Geological Survey data release, <a href=\"https:\/\/doi.org\/10.5066\/F7PV6JNV\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.5066\/F7PV6JNV<\/a>.<\/li>\n<li>Holt, W. E., C. Kreemer, A. J. Haines, L. Estey, C. Meertens, G. Blewitt, and D. Lavallee (2005), Project helps constrain continental dynamics and seismic hazards, Eos Trans. AGU, 86(41), 383\u2013387, , <a href=\"https:\/\/doi.org\/10.1029\/2005EO410002\" rel=\"noopener\" target=\"_blank\"> https:\/\/doi.org\/10.1029\/2005EO410002<\/a>. \/li>\n<li>Jessee, M.A.N., Hamburger, M. W., Allstadt, K., Wald, D. J., Robeson, S. M., Tanyas, H., et al. (2018). A global empirical model for near-real-time assessment of seismically induced landslides. Journal of Geophysical Research: Earth Surface, 123, 1835\u20131859. <a href=\"https:\/\/doi.org\/10.1029\/2017JF004494\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1029\/2017JF004494<\/a><\/li>\n<li>Kreemer, C., J. Haines, W. Holt, G. Blewitt, and D. Lavallee (2000), On the determination of a global strain rate model, Geophys. J. Int., 52(10), 765\u2013770. <\/li>\n<li>Kreemer, C., W. E. Holt, and A. J. Haines (2003), An integrated global model of present-day plate motions and plate boundary deformation, Geophys. J. Int., 154(1), 8\u201334, , <a href=\"https:\/\/doi.org\/10.1046\/j.1365-246X.2003.01917.x\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1046\/j.1365-246X.2003.01917.x<\/a>. <\/li>\n<li>Kreemer, C., G. Blewitt, E.C. Klein, 2014. A geodetic plate motion and Global Strain Rate Model in Geochemistry, Geophysics, Geosystems, v. 15, p. 3849-3889, <a href=\"https:\/\/doi.org\/10.1002\/2014GC005407\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1002\/2014GC005407<\/a>.<\/li>\n<li>Meyer, B., Saltus, R., Chulliat, a., 2017. <a href=\"https:\/\/www.ngdc.noaa.gov\/geomag\/emag2.html\" rel=\"noopener\" target=\"_blank\">EMAG2: Earth Magnetic Anomaly Grid (2-arc-minute resolution) Version <\/a>3. National Centers for Environmental Information, NOAA. Model. <a href=\"https:\/\/doi.org\/10.7289\/V5H70CVX\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.7289\/V5H70CVX<\/a><\/li>\n<li>M\u00fcller, R.D., Sdrolias, M., Gaina, C. and Roest, W.R., 2008, <a href=\"http:\/\/www.earthbyte.org\/people\/dietmar\/Pdf\/Muller_etal_age_rate_asym_G3_2008.pdf\" rel=\"noopener\" target=\"_blank\">Age spreading rates and spreading asymmetry of the world&#8217;s ocean crust<\/a> in Geochemistry, Geophysics, Geosystems, 9, Q04006, <a href=\"https:\/\/doi.org\/10.1029\/2007GC001743\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1029\/2007GC001743<\/a><\/li>\n<li>Pagani,M. , J. Garcia-Pelaez, R. Gee, K. Johnson, V. Poggi, R. Styron, G. Weatherill, M. Simionato, D. Vigan\u00f2, L. Danciu, D. Monelli (2018). Global Earthquake Model (GEM) Seismic Hazard Map (version 2018.1 &#8211; December 2018), DOI: 10.13117\/GEM-GLOBAL-SEISMIC-HAZARD-MAP-2018.1<\/li>\n<li>Silva, V ., D Amo-Oduro, A Calderon, J Dabbeek, V Despotaki, L Martins, A Rao, M Simionato, D Vigan\u00f2, C Yepes, A Acevedo, N Horspool, H Crowley, K Jaiswal, M Journeay, M Pittore, 2018. Global Earthquake Model (GEM) Seismic Risk Map (version 2018.1). <a href=\"https:\/\/doi.org\/10.13117\/GEM-GLOBAL-SEISMIC-RISK-MAP-2018.1\" rel=\"noopener noreferrer\" target=\"_blank\">https:\/\/doi.org\/10.13117\/GEM-GLOBAL-SEISMIC-RISK-MAP-2018.1<\/a><\/li>\n<li>Zhu, J., Baise, L. G., Thompson, E. M., 2017, An Updated Geospatial Liquefaction Model for Global Application, Bulletin of the Seismological Society of America, 107, p 1365-1385, <a href=\"https:\/\/doi.org\/0.1785\/0120160198\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/0.1785\/0120160198<\/a><\/li>\n<p><H3>Specific References<\/H3><\/p>\n<li>Baillard, C., W. C. Crawford, V. Ballu, M. R\u00e9gnier, B. Pelletier, and E. Garaebiti (2015), Seismicity and shallow slab geometry in the central Vanuatu subduction zone, J. Geophys. Res. Solid Earth,120,5606\u20135623, <a href=\"https:\/\/doi.org\/10.1002\/2014JB011853\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1002\/2014JB011853<\/a><\/li>\n<li>Benz, H.M., Herman, Matthew, Tarr, A.C., Furlong, K.P., Hayes, G.P., Villase\u00f1or, Antonio, Dart, R.L., and Rhea, Susan, 2011. Seismicity of the Earth 1900\u20132010 eastern margin of the Australia plate: U.S. Geological Survey Open-File Report 2010\u20131083-I, scale 1:8,000,000.<\/li>\n<li>Bergeot, N., M. N. Bouin, M. Diament, B. Pelletier, M. Re\u00b4gnier, S. Calmant, and V. Ballu (2009), Horizontal and vertical interseismic velocity fields in the Vanuatu subduction zone from GPS measurements: Evidence for a central Vanuatu locked zone, J. Geophys. Res., 114, B06405, <a href=\"https:\/\/doi.org\/10.1029\/2007JB005249\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1029\/2007JB005249<\/a><\/li>\n<li>Cleveland, K.M., Ammon, C.J., and Lay, T., 2014. <a href=\"http:\/\/earthjay.com\/earthquakes\/20160406_vanuatu\/cleveland_etal_2014_earthquakes_vanuatu.pdf\" target=\"_blank\" rel=\"noopener\">Large earthquake processes in the northern Vanuatu subduction zone<\/a> in Journal of Geophysical Research: Solid Earth, v. 119, p. 8866-8883, doi:10.1002\/2014JB011289.<\/li>\n<li>Deng, C., Jenner, F. E., Wan, B., &#038; Li, J.-L. (2022). The influence of ridge subduction on the geochemistry of Vanuatu arc magmas. Journal of Geophysical Research: Solid Earth, 127, e2021JB022833. <a href=\"https:\/\/doi.org\/10.1029\/2021JB022833\" rel=\"noopener\" target=\"_blank\">https:\/\/doi.org\/10.1029\/2021JB022833<\/a><\/li>\n<li>Hayes, G. P., D. J. Wald, and R. L. Johnson, 2012. <a href=\"http:\/\/earthquake.usgs.gov\/data\/slab\/\">Slab1.0: A three-dimensional model of global subduction zone geometries<\/a>, J. Geophys. Res., 117, B01302, doi:10.1029\/2011JB008524.<\/li>\n<li>Richards, S., Holm., R., Barber, G., 2011. <a href=\"http:\/\/geology.gsapubs.org\/content\/39\/8\/787.abstract\" target=\"_blank\" rel=\"noopener\">When slabs collide: A tectonic assessment of deep earthquakes in the Tonga-Vanuatu region<\/a>, Geology, v. 39, pp. 787-790.<\/li>\n<p><a href=\"https:\/\/en.wikipedia.org\/wiki\/Convergent_boundary#\/media\/File:Oceanic-oceanic_destructive_plate_boundary.svg\" target=\"_blank\" rel=\"noopener\"><strong>Oceanic-Oceanic Subduction Zone Figure<\/strong><\/a><br \/>\n<strong>Music Reference<\/strong> (in 1900-2016 seismicity video)<\/p>\n<li>Bumba Crossing Kevin MacLeod (incompetech.com) | Licensed under Creative Commons: By Attribution 3.0 License | http:\/\/creativecommons.org\/licenses\/by\/3.0\/<\/li>\n<\/ul>\n<ul>\n<H2><strong><font color=\"orange\">Social Media<\/font><\/strong><\/H2><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\"><a href=\"https:\/\/twitter.com\/hashtag\/EarthquakeReport?src=hash&amp;ref_src=twsrc%5Etfw\">#EarthquakeReport<\/a> for M7.0 <a href=\"https:\/\/twitter.com\/hashtag\/Earthquake?src=hash&amp;ref_src=twsrc%5Etfw\">#Earthquake<\/a> in <a href=\"https:\/\/twitter.com\/hashtag\/Vanuatu?src=hash&amp;ref_src=twsrc%5Etfw\">#Vanuatu<\/a><\/p>\n<p>Felt intensity MMI 7<\/p>\n<p>Read more about regional tectonics in 2017 report<a href=\"https:\/\/t.co\/Nvbes3IH0L\">https:\/\/t.co\/Nvbes3IH0L<\/a><a href=\"https:\/\/t.co\/DbR3abwbKC\">https:\/\/t.co\/DbR3abwbKC<\/a> <a href=\"https:\/\/t.co\/0Yjc8ywQVA\">pic.twitter.com\/0Yjc8ywQVA<\/a><\/p>\n<p>&mdash; Jason &quot;Jay&quot; R. Patton (@patton_cascadia) <a href=\"https:\/\/twitter.com\/patton_cascadia\/status\/1612119816546160640?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\"><a href=\"https:\/\/twitter.com\/hashtag\/EarthquakeReport?src=hash&amp;ref_src=twsrc%5Etfw\">#EarthquakeReport<\/a> for the M 7.0 <a href=\"https:\/\/twitter.com\/hashtag\/Earthquake?src=hash&amp;ref_src=twsrc%5Etfw\">#Earthquake<\/a> offshore of <a href=\"https:\/\/twitter.com\/hashtag\/Vanuatu?src=hash&amp;ref_src=twsrc%5Etfw\">#Vanuatu<\/a><\/p>\n<p>high intensity felt (MMI 7.8)<\/p>\n<p>no observed tsunami on tide gages<\/p>\n<p>read more in the report<a href=\"https:\/\/t.co\/gcdHfboaF5\">https:\/\/t.co\/gcdHfboaF5<\/a> <a href=\"https:\/\/t.co\/ySQT4lXgQS\">pic.twitter.com\/ySQT4lXgQS<\/a><\/p>\n<p>&mdash; Jason &quot;Jay&quot; R. Patton (@patton_cascadia) <a href=\"https:\/\/twitter.com\/patton_cascadia\/status\/1612219506658770944?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Notable quake, preliminary info: M 7.2 &#8211; 38 km WSW of Port-Olry, Vanuatu <a href=\"https:\/\/t.co\/35aMQ7mTt7\">https:\/\/t.co\/35aMQ7mTt7<\/a><\/p>\n<p>&mdash; USGS Earthquakes (@USGS_Quakes) <a href=\"https:\/\/twitter.com\/USGS_Quakes\/status\/1612066724010160130?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">The waves from the M7.0 earthquake near Vanuatu are passing under me on the east coast of the US right now! <\/p>\n<p>Look carefully at the scale on the 2nd image &#8211; by the time they reach VA these waves are about 1\/2 the width of a human hair so far too small to feel. 1\/n <a href=\"https:\/\/t.co\/q56UWKN6WA\">pic.twitter.com\/q56UWKN6WA<\/a><\/p>\n<p>&mdash; Wendy Bohon, PhD \ud83c\udf0f (@DrWendyRocks) <a href=\"https:\/\/twitter.com\/DrWendyRocks\/status\/1612097168210563074?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Waves from the M7.0 earthquake in Vanuatu shown on a nearby station using Station Monitor. <a href=\"https:\/\/t.co\/Tir0KZELXN\">https:\/\/t.co\/Tir0KZELXN<\/a> <a href=\"https:\/\/t.co\/JUey79Uizv\">pic.twitter.com\/JUey79Uizv<\/a><\/p>\n<p>&mdash; EarthScope Consortium (@EarthScope_sci) <a href=\"https:\/\/twitter.com\/EarthScope_sci\/status\/1612094647404474439?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Back projection for the M7.0 earthquake in Vanuatu<a href=\"https:\/\/t.co\/j6otX26QHa\">https:\/\/t.co\/j6otX26QHa<\/a> <a href=\"https:\/\/t.co\/wiVXSX7iop\">pic.twitter.com\/wiVXSX7iop<\/a><\/p>\n<p>&mdash; EarthScope Consortium (@EarthScope_sci) <a href=\"https:\/\/twitter.com\/EarthScope_sci\/status\/1612109187340963841?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">One hour ago, M7.0 <a href=\"https:\/\/twitter.com\/hashtag\/earthquake?src=hash&amp;ref_src=twsrc%5Etfw\">#earthquake<\/a> in the Espiritu Santo island, Vanuatu. Very shallow!<a href=\"https:\/\/t.co\/2cwp078v1N\">https:\/\/t.co\/2cwp078v1N<\/a> <a href=\"https:\/\/t.co\/wqrjbGSwMN\">pic.twitter.com\/wqrjbGSwMN<\/a><\/p>\n<p>&mdash; Jos\u00e9 R. Ribeiro (@JoseRodRibeiro) <a href=\"https:\/\/twitter.com\/JoseRodRibeiro\/status\/1612085348204707841?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Preliminary M6.9 <a href=\"https:\/\/twitter.com\/hashtag\/Earthquake?src=hash&amp;ref_src=twsrc%5Etfw\">#Earthquake<\/a><br \/>ID: <a href=\"https:\/\/twitter.com\/hashtag\/rs2023anvawm?src=hash&amp;ref_src=twsrc%5Etfw\">#rs2023anvawm<\/a><br \/>90km\/56miles from <a href=\"https:\/\/twitter.com\/hashtag\/Luganville?src=hash&amp;ref_src=twsrc%5Etfw\">#Luganville<\/a>, in <a href=\"https:\/\/twitter.com\/hashtag\/VanuatuIslands?src=hash&amp;ref_src=twsrc%5Etfw\">#VanuatuIslands<\/a><br \/>2023-01-08 12:32 UTC<a href=\"https:\/\/twitter.com\/raspishake?ref_src=twsrc%5Etfw\">@raspishake<\/a> network<\/p>\n<p>Join the largest <a href=\"https:\/\/twitter.com\/hashtag\/CitizenScience?src=hash&amp;ref_src=twsrc%5Etfw\">#CitizenScience<\/a> <a href=\"https:\/\/twitter.com\/hashtag\/seismograph?src=hash&amp;ref_src=twsrc%5Etfw\">#seismograph<\/a> community \u27a1 <a href=\"https:\/\/t.co\/Y5O0dgJqJF\">https:\/\/t.co\/Y5O0dgJqJF<\/a><\/p>\n<p>EVENT \u27a1 <a href=\"https:\/\/t.co\/wk0tSVfL2i\">https:\/\/t.co\/wk0tSVfL2i<\/a> <a href=\"https:\/\/t.co\/NjEfzppBQE\">pic.twitter.com\/NjEfzppBQE<\/a><\/p>\n<p>&mdash; Raspberry Shake Earthquake Channel (@raspishakEQ) <a href=\"https:\/\/twitter.com\/raspishakEQ\/status\/1612066869292179457?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">No <a href=\"https:\/\/twitter.com\/hashtag\/tsunami?src=hash&amp;ref_src=twsrc%5Etfw\">#tsunami<\/a> threat to Australia from magnitude 6.9 <a href=\"https:\/\/twitter.com\/hashtag\/earthquake?src=hash&amp;ref_src=twsrc%5Etfw\">#earthquake<\/a> near Vanuatu Islands. Latest advice at <a href=\"https:\/\/t.co\/Tynv3ZQpEq\">https:\/\/t.co\/Tynv3ZQpEq<\/a>. <a href=\"https:\/\/t.co\/eoxJwLiQbo\">pic.twitter.com\/eoxJwLiQbo<\/a><\/p>\n<p>&mdash; Bureau of Meteorology, Australia (@BOM_au) <a href=\"https:\/\/twitter.com\/BOM_au\/status\/1612069424705712129?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">The eastern margin of the Australia plate is so sesimically active due to high rates of convergence between the Australia and Pacific plates. You can view earthquakes in this area (and around the world) in 3D using the IRIS Earthquake Browser, like I\u2019ve done here. <a href=\"https:\/\/t.co\/KBRtwCagcl\">pic.twitter.com\/KBRtwCagcl<\/a><\/p>\n<p>&mdash; Wendy Bohon, PhD \ud83c\udf0f (@DrWendyRocks) <a href=\"https:\/\/twitter.com\/DrWendyRocks\/status\/1612092412893057028?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"de\" dir=\"ltr\">Schweres gef\u00e4hrliches Erdbeben im Norden von Vanuatu: Tsunami-Warnung <a href=\"https:\/\/t.co\/1RRYtpqeKx\">https:\/\/t.co\/1RRYtpqeKx<\/a> <a href=\"https:\/\/t.co\/3I6S2KfGCA\">pic.twitter.com\/3I6S2KfGCA<\/a><\/p>\n<p>&mdash; Erdbebennews (@Erdbebennews) <a href=\"https:\/\/twitter.com\/Erdbebennews\/status\/1612072108951048193?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Today 7.0 Mw Central <a href=\"https:\/\/twitter.com\/hashtag\/VANUATU?src=hash&amp;ref_src=twsrc%5Etfw\">#VANUATU<\/a>\ud83c\uddfb\ud83c\uddfa, ruptured at ~23 km depth along the subduction\\megathrust fault (associated to the d&#39;Entrecasteaux Zone).<\/p>\n<p>Tecto-schematic 3D figure from :<br \/>\ud83d\udd39The Influence of Ridge Subduction on the Geochemistry of Vanuatu Arc Magmas (2022)<a href=\"https:\/\/t.co\/ykBd2L4myK\">https:\/\/t.co\/ykBd2L4myK<\/a> <a href=\"https:\/\/t.co\/mFNDdrTkvY\">pic.twitter.com\/mFNDdrTkvY<\/a><\/p>\n<p>&mdash; Abel Seism\ud83c\udf0fS\u00e1nchez (@EQuake_Analysis) <a href=\"https:\/\/twitter.com\/EQuake_Analysis\/status\/1612101137662107648?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">The M7.0 earthquake in Vanuatu occurred at a depth of ~28 km in a seismically active area that experiences frequent large earthquakes. Earthquakes in this region are caused by the Australian Plate subducting under the Pacific Plate.<a href=\"https:\/\/t.co\/OM7bvJKw7W\">https:\/\/t.co\/OM7bvJKw7W<\/a> <a href=\"https:\/\/t.co\/xq9NfDJTiX\">pic.twitter.com\/xq9NfDJTiX<\/a><\/p>\n<p>&mdash; EarthScope Consortium (@EarthScope_sci) <a href=\"https:\/\/twitter.com\/EarthScope_sci\/status\/1612107131871965187?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<blockquote class=\"twitter-tweet\">\n<p lang=\"en\" dir=\"ltr\">Global surface and body wave sections from the M7.0 earthquake in Vanuatu<a href=\"https:\/\/t.co\/60idTVV9BN\">https:\/\/t.co\/60idTVV9BN<\/a> <a href=\"https:\/\/t.co\/6gJaLM01LZ\">pic.twitter.com\/6gJaLM01LZ<\/a><\/p>\n<p>&mdash; EarthScope Consortium (@EarthScope_sci) <a href=\"https:\/\/twitter.com\/EarthScope_sci\/status\/1612108870608130049?ref_src=twsrc%5Etfw\">January 8, 2023<\/a><\/p><\/blockquote>\n<p> <script async src=\"https:\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><\/p>\n<p>I cannot confirm this is from today&#8217;s earthquake:<\/p>\n<p><iframe loading=\"lazy\" width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/AUR5NDHqs4k\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen><\/iframe><\/p>\n<\/ul>\n<p><H2><font color=\"orange\"><strong>Return to the <a href=\"http:\/\/earthjay.com\/?page_id=3218\">Earthquake Reports page<\/a>.<\/font><\/strong><\/H2><\/p>\n<ul>\n<li>Sorted by <a href=\"http:\/\/earthjay.com\/?page_id=3219\">Magnitude<\/a><\/li>\n<li>Sorted by <a href=\"http:\/\/earthjay.com\/?page_id=3220\">Year<\/a><\/li>\n<li>Sorted by <a href=\"http:\/\/earthjay.com\/?page_id=9351\">Day of the Year<\/a><\/li>\n<li>Sorted By <a href=\"http:\/\/earthjay.com\/?page_id=3226\">Region<\/a><\/li>\n<\/ul>\n<p><!--\n\u00b0\n\u2265\n\u00d1\n\u00f6\n\u00e1\n\u00b1\n\n\n\n\n<\/p>\n","protected":false},"excerpt":{"rendered":"<div class=\"entry-summary\">\nEarly this morning (my time) I got a notification from the Pacific Tsunami Warning Center that there was no tsunami threat from an M 7.2 earthquake in the Vanuatu Islands. Tsunami Info Stmt: M7.2 Vanuatu Islands 0433PST Jan 8: Tsunami&hellip;\n<\/div>\n<div class=\"link-more\"><a href=\"https:\/\/earthjay.com\/?p=10727\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &ldquo;Earthquake Report: M 7.0 Vanuatu&rdquo;<\/span>&hellip;<\/a><\/div>\n","protected":false},"author":3,"featured_media":10739,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0},"categories":[5,6,34],"tags":[],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/earthjay.com\/wp-content\/uploads\/2023\/01\/20230108_vanuatu_interpretation-scaled.jpg","_links":{"self":[{"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/posts\/10727"}],"collection":[{"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/earthjay.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10727"}],"version-history":[{"count":12,"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/posts\/10727\/revisions"}],"predecessor-version":[{"id":10750,"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/posts\/10727\/revisions\/10750"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/earthjay.com\/index.php?rest_route=\/wp\/v2\/media\/10739"}],"wp:attachment":[{"href":"https:\/\/earthjay.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10727"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/earthjay.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10727"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/earthjay.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10727"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}