Crustal and upper mantle structures of the brazilian coast

The Rayleigh wave phase and group velocities in the period range of 24–39 sec, obtained from two earthquakes which occurred in northeastern brazil and which were recorded by the Brazilian seismological station RDJ (Rio de Janeiro), have been used to study crustal and upper mantle structures of the Brazilian coastal region. Three crustal and upper mantle models have been tried out to explain crustal and upper mantle structures of the region. The upper crust has not been resolved, due basically to the narrow period range of the phase and group velocities data. The phase velocity inversions have exhibited good resolutions for both lower crust and upper mantle, with shear wave velocities characteristic of these regions. The group velocity data inversions for these models have showed good results only for the lower crust. The shear wave velocities of the lower crust (3.86 and 3.89 km/sec), obtained with phase velocity inversions, are similar to that (=3.89 km/sec) found byHwang (1985) to the eastern South American region, while group velocity inversions have presented shear velocity (=3.75 km/sec) similar to that (=3.78 km/sec) found byLazcano (1972) to the Brazilian shield. It was not possible to define sharply the crust-mantle transition, but an analysis of the phase and group velocity inversions results has indicated that the total thickness of the crust should be between 30 and 39 km. The crustal and upper mantle model, obtained with phase velocity inversion, can be used as a preliminary model for the Brazilian coast.     

The upper mantle structure of the yakutian kimberlite province,eastern Russia

Deep seismic sounding in the region of the Mirnyi kimberlite field indicates that the boundary velocity of the uppermost mantle is elevated (v _b=8.6–8.8 km/sec) and extremely variable near the Mir kimberlite pipe. These velocity heterogeneities are probably associated with the kimberlite magmatism and may be useful in the identification of other kimberlite fields.     

Crustal structure of the Peninsular India

Summary Earthquake parameters for the forty aftershocks of the main Koyna earthquake of 10 December, 1967, have been determined. Depths of the foci of the earthquakes have been found to vary between 2 to 17 km. The velocities for the phasesP _g ,P ^*,P _n have been observed to be 5.78±0.00, 6.58±0.04, 8.19±0.02 km/sec, and forS _g ,S ^*,S _n to be 3.42±0.00, 3.92±0.01 and 4.62±0.01 km/sec respectively. A two-layered crustal model has been interpreted for the Peninsular shield with the average thickness of the granitic layer as 20 km and that for the basaltic layer as 18.7 km. A plot of the epicenters suggests a NNE to SSW orientation of the fault.     

云南地区地壳速度模型研究及应用

选取2009~2014年发生在云南地区、每个地震均在10个以上台站有记录的7412个地震数据,作走时曲线。同时为提高精度,重点对其中每个地震均在80%以上台站有记录的、ML≥3.0的83个地震数据,再作线性分析、折合走时曲线和区间稳定性分析,结合前人研究成果得到了研究区的初始地壳速度模型。选取2010~2014年云南省内M≥3.0的200次地震,采用Hyposat批处理方法迭代初始速度模型,以及对S波作分层速度拟合,得到云南地区的地壳速度模型,即2015云南模型:v_(P1)=6.01km/s,v_(P2)=6.60km/s,v_(Pn)=7.89km/s,H_1=20km,H_2=21km,v_(S1)=3.52km/s,v_(S2)=3.86km/s,v_(sn)=4.43km/s。基于新模型的地震重定位分析表明,云南地区地震事件大多发生于20km内的上地壳;对2011年3月10日盈江M5.8和2014年8月3日鲁甸M6.5典型地震进行重定位,得出震源深度分别与精定位结果和震中强震台震源距接近,表明新的一维速度模型能更好地反映研究区平均速度结构。     

Source Parameters of the Deadly M<Subscript>w</Subscript> 7.6 Kashmir Earthquake of 8 October, 2005

During the last six years, National Geophysical Research Institute, Hyderabad has established a semi-permanent seismological network of 5–8 broadband seismographs and 10–20 accelerographs in the Kachchh seismic zone, Gujarat with a prime objective to monitor the continued aftershock activity of the 2001 M_w 7.7 Bhuj mainshock. The reliable and accurate broadband data for the 8 October M_w 7.6 2005 Kashmir earthquake and its aftershocks from this network as well as Hyderabad Geoscope station enabled us to estimate the group velocity dispersion characteristics and one-dimensional regional shear velocity structure of the Peninsular India. Firstly, we measure Rayleigh-and Love-wave group velocity dispersion curves in the period range of 8 to 35 sec and invert these curves to estimate the crustal and upper mantle structure below the western part of Peninsular India. Our best model suggests a two-layered crust: The upper crust is 13.8 km thick with a shear velocity (Vs) of 3.2 km/s; the corresponding values for the lower crust are 24.9 km and 3.7 km/sec. The shear velocity for the upper mantle is found to be 4.65 km/sec. Based on this structure, we perform a moment tensor (MT) inversion of the bandpass (0.05–0.02 Hz) filtered seismograms of the Kashmir earthquake. The best fit is obtained for a source located at a depth of 30 km, with a seismic moment, Mo, of 1.6 × 10²⁷ dyne-cm, and a focal mechanism with strike 19.5°, dip 42°, and rake 167°. The long-period magnitude (M_A ~ M_w) of this earthquake is estimated to be 7.31. An analysis of well-developed sPn and sSn regional crustal phases from the bandpassed (0.02–0.25 Hz) seismograms of this earthquake at four stations in Kachchh suggests a focal depth of 30.8 km.     

The amplitude ratioPcP/P and the core-mantle boundary

Summary Using the Haskell matrix formulation, theoretical reflection coefficient curves have been calculated for a multi-layered core-mantle boundary for comparison with observational data. Two cases are considered, first when the shear velocity in the core is equal to zero and second when the core has a finite rigidity. If the velocity contrast is large between the imbedded layer and the mantle, the reflection coefficient curves for the multi-layered medium are irregular in shape as compared to those for two half-spaces, representing the core and the mantle, respectively. The reflection coefficient curves show an oscillatory character if the imbedded layer is thick and has a high velocity contrast.The observational data consist of short-period vertical-component seismograph records ofP andPcP from nuclear explosions in the Aleutian chain, Nevada, Novaya Zemlya, Kazakh and Sahara. Attenuation and geometrical spreading are taken into consideration. Four different models for the quality factorQ are applied to the observational data. The data are found to be much affected by theQ-model used for the corrections.Based on proposedQ-values, a model for the core-mantle boundary is found, characterized by two low-velocity layers at the bottom of the mantle. The thicknesses are 16.10 km (outer layer) and 19.96 km (inner layer), the compressional wave velocities 12.17 km/sec and 10.94 km/sec and the shear wave velocities are 6.29 km/sec and 5.33 km/sec, respectively. A better fit to this model is found when in addition the shear velocity in the outer core is 2.20 km/sec and the density ratio at the core-mantle boundary is 1.07. In other words, the observations favour a layer of finite rigidity in the outer core rather than a fluid one.     

Upper mantle structure of the Apulian plate from Rayleigh waves

Phase velocities of Rayleigh waves for the Adriatic Sea area are obtained in the period range 25–190 sec along the path (l'Aquila-Trieste) AQU-TRI and 20–167 sec along the path (Trieste-Bari) TRI-BAI.The phase velocities are systematically higher than the known values for the surrounding regions. The data inversion indicates the presence of a lithosphere typical of stable continental areas with clear high-velocity lid (V _s 4.6 km/sec) overlying a well developed low velocity zone (V _s 4.2 km/sec).P. F. Geodinamica C.N.R., Roma Pubbl. N. 189.     

Structural heterogeneity of an ultra-low-velocity zone beneath the Philippine Islands: Implications for core–mantle chemical interactions induced by massive partial melting at the bottom of the mantle

An ScP phase reflected and converted at the core–mantle boundary (CMB) beneath the region east of the Philippine Islands shows clear pre- and postcursors, recorded on short-period seismic networks in Japan. These waveform variations can be explained by interaction of the ScP wavefield with thin layers at the CMB. The results of forward modeling of double-array stacks reveal two different structural heterogeneities in the lowermost mantle beneath the region east of the Philippine Islands. One of the structures represents a decreased velocity, and increased density across the reflector at the lowermost ～10 km of the mantle, with P- and S-wave velocity reductions of 5–10% and ～30%, respectively, and an increase in density of 5–10%. Another structure consists of a pair of reflectors at ～10 km and ～5 km above the CMB, both of which are characterized by reduced P- and S-wave velocities. The upper reflector is the interface of a low-velocity zone in which P- and S-wave velocities decrease of 10% and 30%, respectively, accompanied by an extremely large increase in density (20–25%). The lower reflector is characterized by a 25% reduction in S-wave velocity relative to the above low-velocity layer, as well as a 5% decrease in P-wave velocity and no change in density. The nature of the low-velocity zone detected locally at the CMB is comparable with that of ultra-low-velocity zones (ULVZs) observed by various seismic probes in the South Pacific and Central America. Extensive observations of the ULVZ beneath the region east of the Philippine Islands indicate massive partial melting at the bottom of the mantle. Low-S-velocity basal layer partly detected within the ULVZ may be resulting from core–mantle chemical interactions, driven by massive partial melting.     

Source Parameters of the 8 October, 2005 M<Subscript>w</Subscript>7.6 Kashmir Earthquake

During the last six years, the National Geophysical Research Institute, Hyderabad has established a semi-permanent seismological network of 5 broadband seismographs and 10 accelerographs in the Kachchh seismic zone, Gujarat, with the prime objective to monitor the continued aftershock activity of the 2001 M_w7.7 Bhuj mainshock. The reliable and accurate broadband data for the M_w 7.6 (8 Oct., 2005) Kashmir earthquake and its aftershocks from this network, as well as from the Hyderabad Geoscope station, enabled us to estimate the group velocity dispersion characteristics and the one-dimensional regional shear-velocity structure of peninsular India. Firstly, we measure Rayleigh- and Love-wave group velocity dispersion curves in the range of 8 to 35 sec and invert these curves to estimate the crustal and upper mantle structure below the western part of peninsular India. Our best model suggests a two-layered crust: The upper crust is 13.8-km thick with a shear velocity (Vs) of 3.2 km/s; the corresponding values for the lower crust are 24.9 km and 3.7 km/sec. The shear velocity for the upper mantle is found to be 4.65 km/sec. Based on this structure, we perform a moment tensor (MT) inversion of the bandpass (0.05–0.02 Hz) filtered seismograms of the Kashmir earthquake. The best fit is obtained for a source located at a depth of 30 km, with a seismic moment, Mo, of 1.6 × 10²⁷ dyne-cm, and a focal mechanism with strike 19.5°, dip 42°, and rake 167°. The long-period magnitude (M_A ~ M_w) of this earthquake is estimated to be 7.31. An analysis of well-developed sPn and sSn regional crustal phases from the bandpassed (0.02–0.25 Hz) seismograms of this earthquake at four stations in Kachchh suggests a focal depth of 30.8 km.     

Iterative deconvolution of teleseismic P waves from the Thessaloniki (N. Greece) earthquake of June 20, 1978

Teleseismic long-period P waves from the June 20, 1978, Thessaloniki (N. Greece) earthquake (M _s=6.4) were modeled in an attempt to extract information about asperities or barriers on the fault plane. The analysis is based on the inversion method of complex P waves developed by Kikuchi and Kanamori (1982). A far-field source time function with a rise time of 2 sec and a process time of 5 sec is inferred, corresponding to a source dimension of about 10 km when a rupture velocity of 2 km/sec is assumed.The source depth of this shock, estimated by matching synthetic seismograms to observations, is found to be 8 km. The sum of the seismic moments of the individual subevents amounts to 3.3×10²⁵ dyn-cm.     

On the seismic phasesP n andS n as recorded in Fennoscandia

Summary P _n velocities determined from seismic refraction measurements, show significant differences between Southern Finland (7.96 km/sec) and Southeastern Norway (8.20 km/sec). TheP _n/S_n velocity ratios (k) were determined from earthquake and explosion data, and the observed variation ofk indicates lateral variations in theP _n and/orS _n velocities in Fennoscandia.     

Inversion of seismic and gravity data for the composition and core sizes of the Moon

We model the internal structure of the Moon, initially homogeneous and later differentiated due to partial melting. The chemical composition and the internal structure of the Moon are retrieved by the Monte-Carlo inversion of the gravity (the mass and the moment of inertia), seismic (compressional and shear velocities), and petrological (balance equations) data. For the computation of phase equilibrium relations and physical properties, we have used a method of minimization of the Gibbs free energy combined with a Mie-Gr@uneisen equation of state within the CaO-FeO-MgO-Al₂O₃-SiO₂ system. The lunar models with a different degree of constraints on the solution are considered. For all models, the geophysically and geochemically permissible ranges of seismic velocities and concentrations in three mantle zones and the sizes of Fe-10%S core are estimated. The lunar mantle is chemically stratified; different mantle zones, where orthopyroxene is the dominant phase, have different concentrations of FeO, Al₂O₃, and CaO. The silicate portion of the Moon (crust + mantle) may contain 3.5–5.5% Al₂O₃ and 10.5–12.5% FeO. The chemical boundary between the middle and the lower mantle lies at a depth of 620–750 km. The lunar models with and without a chemical boundary at a depth of 250–300 km are both possible. The main parameters of the crust, the mantle, and the core of the Moon are estimated. At the depths of the lower mantle, the P and S velocities range from 7.88 to 8.10 km/s and from 4.40 to 4.55 km/s, respectively. The radius of a Fe-10%S core is 340 ± 30 km.     

Observations of teleseismicPn phases

Summary Numerous observations of teleseismicPn phases have been made on short-period seismograph records in Sweden. The observations now cover the distance range of 2360 to 4670 km, that is about six times the distance range reported in an earlier paper. The propagation paths are exclusively confined to the Russian platform, which means that a very homogeneous structure is required for the propagation ofPn to large distances. The relation between travel-timet (sec) and distance along the earth's surface (km) ist=: (8.20±0.12)+(0±6), based on 30 observations. The real velocity ofPn (underneath Moho) is 8.15±0.12 km/sec and the corresponding Poisson's ratio, obtained by combination with the teleseismicSn velocity (4.72 km/sec), is 0.248. These are averages for the Russian platform. The problem of the relative occurrence ofPn andSn in teleseismic records is briefly discussed.     

A study of the crustal structure beneath the Himalayas from body waves

Summary The crustal structure beneath the Himalayas has been investigated using body wave data from near earthquakes having epicentres over the Himalayas and recorded by the observatories situated over, or very near, the foothills of the mountains. A three-layered crustal model, without the top sedimentary layer, with velocities for theP wave group in Granite I, Granite II and the Basaltic layer as 5.48, 6.00 and 6.45 and for theS wave group as 3.33, 3.56 and 3.90 km/sec respectively, has been interpreted. The upper mantle velocity for theP wave has been observed to be 8.07 km/sec and for theS wave as 4.57 km/sec. Average thickness for the Granite I layer has been computed as 22.7 km, for the Granite II layer as 16.3 km and for the Basaltic layer as 18.7 km. Crustal and sub-crustal velocities indicate a lower trend under the mountain. A thicker crust has been obtained beneath the Himalayas.     

Short-period rayleigh waves recorded in the western carpathians during dss

Summary The periods, the maximum absolute displacement amplitudes and the maximum particle velocities of the surface waves, propagating in the weathered layer are investigated. Dependences of the parameters under discussion on the distance r (km) between sites and shot points are expressed for distances from 3.6 to 38.6 km by the functions: T(s)=0.40r ^0.30 , A _max (m)==502.73r ^–1.93 and v _max (mm s –1)=7.95 r –2.22.     

Plume Generation Zones at the margins of Large Low Shear Velocity Provinces on the core–mantle boundary

Large Igneous Province (LIP) eruption sites of the past 300 My lie vertically above 1% slow shear wave velocity (V_s) contours bounding the African and Pacific Large Low Shear Velocity Provinces (LLSVPs) at the core–mantle boundary (CMB), or in the cases of the Siberian and Columbia River LIPs, bounding one or other of two smaller, Low Shear Velocity Provinces (LSVPs). Steep gradients in V_s at the CMB coincide with those 1% slow contours. The sites of 24 active hotspot volcanoes project down to the same narrowly defined borders of the LLSVPs at the CMB. Plumes that have generated LIPs and major hotspot volcanoes have risen only from the immediate neighbourhoods of the 1% slow V_s contours at the CMB which thus define Plume Generation Zones (PGZs). PGZs projected vertically upward approximately match the + 10 m elevation contour of the geoid showing that the LLSVPs are a dominant control on the positively elevated geoid. Minima in the frequency distribution of shear wave velocities in the lowermost mantle near V_s = ? 1% indicate that regions with more negative velocities, forming ～ 2% of total mantle mass, are likely to be of material compositionally different from the rest of the mantle. Because all LIP eruption sites with ages younger than 300 Ma lie above the borders of LLSVPs or LSVPs at the CMB, PGZ footprints are inferred to have remained in the same places for the past 300 My. Because no plumes have risen from the interior of the LLSVPs and because no lithospheric slabs have penetrated those bodies the volumes of the LLSVPs are inferred to have also remained unchanged for the past 300 My. Because the LLSVPs are the dominant control on the positively elevated areas of the geoid those too must have remained as they now are since 300 Ma. The LLSVPs are not rising buoyant objects but stable features of the deep mantle. LIPs have been erupted throughout the past 2.5 Gy indicating that PGZs comparable to those of the past 0.3 Gy and LLSVPs (of which PGZs mark the margins at the CMB) have also existed for at least that long. LLSVPs could thus form the isolated reservoir invoked by some to explain the distinctive isotopic compositions of terrestrial rocks. PGZs lie at places where the boundaries of: (i) The outer core, (ii) one of the LLSVPs or LSVPs, and (iii) the seismically faster part of the deep mantle meet. Horizontal temperature gradients across the steeply inclined margins to the LLSVPs, the interiors of which are hotter than the surrounding mantle, at the CMB are key controls for the generation of plumes. Near the CMB the association of the high temperature of the outer core with an inclined thermal boundary layer at the margins of LLSVPs facilitates the generation of mantle plumes in the PGZs.     

Pa andSa waves and the upper mantle

Summary This investigation is based on records of 96 earthquakes withPa andSa written by the Press-Ewing instruments at Uppsala in the interval June 1961–December 1962.Pa andSa waves are observed for all earthquake regions, irrespective of distance, focal depth or path properties. They have significantly higher velocities under continents than under oceans, which demonstrates corresponding differences in the upper mantle. Continental velocities are 8.35 km/sec (Pa) and 4.56 km/sec (Sa), oceanic velocities 8.01 km/sec (Pa) and 4.45 km/sec (Sa). The most frequent periods are 10 sec (Pa) and 20 sec (Sa). They are independent of distance forPa but increase with distance forSa. The best developedPa andSa are obtained for earthquakes at focal depths less than about 60 km. The particle motion ofSa may be anything from pureSV to pureSH motion and has high correlation to the particle motion ofS. The apparent angles of emergence (in average 51° forPa and 54° forSa) vary with distance. On the basis of our observations it is suggested thatPa andSa propagate by multiple reflections under grazing incidence under the Moho discontinuity.

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Zusammenfassung Die vorliegende Untersuchung gründet sich auf die Registrierungen von 96 Erdbeben mitPa- undSa-Wellen, die mit Hilfe der Press-Ewing Instrumente zu Uppsala im Zeitraum Juli 1961–Dezember 1962 aufgenommen wurden. DiePa- undSa-Wellen sind für alle seismischen Regionen beobachtet worden, unabhängig von Entfernung, Herdtiefe oder Wellenweg. Sie haben bedeutend höhere Geschwindigkeiten unter den Kontinenten als unter den Ozeanen, was einen entsprechenden Unterschied im oberen Erdmantel beweist. Die kontinentalen Geschwindigkeiten betragen 8.35 km/sec (Pa) und 4.56 km/sec (Sa), die ozeanischen Geschwindigkeiten 8.01 km/sec (Pa) und 4.45 km/sec (Sa). Die am häufigsten vorkommenden Perioden betragen 10 sec (Pa) und 20 sec (Sa). Sie sind unabhängig von der Entfernung fürPa aber wachsen mit der Entfernung fürSa. Die am besten entwickeltenPa- undSa-Wellen werden für Erdbeben mit kleinerer Herdtiefe als rund 60 km beobachtet. FürSa wird jede beliebige Orbitalbewegung zwischenSV undSH beobachtet. Sie hat eine hohe Korrelation mit der Orbitalbewegung vonS. Die scheinbaren Emergenzwinkel (durchschnittlich 51° fürPa und 54° fürSa) variieren mit der Entfernung. Auf Grund unserer Beobachtungen wird die Hypothese aufgestellt, dass sich diePa-undSa-Wellen durch Mehrfachreflexionen, bei tangentialem Einfall, unter der Moho-Diskontinuität ausbreiten.

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Resumen La presente investigación está basada en los sismogramas de 96 terremotos, que muestranPa ySa, registrados por los sismógrafos de Uppsala (Press-Ewing), durante el periodo Junio 1961 a Diciembre 1962. Las fasesPa ySa se observan en todas las regiones sismicas, independientemente de la distancia, de la profundidad focal ó de las propiedades de la trayectoria. Tienen velocidades significativamente mayores bajo continentes que bajo los océanos, lo que demuestra la existencia de diferencias en el manto superior. Las velocidades continentales son 8.35 km/seg (Pa) y 4.56 km/seg (Sa) y las oceánicas 8.01 km/seg (Pa) y 4.45 km/seg (Sa). Los periodos mas frecuentes son 10 segundos paraPa y 20 segundos paraSa. Tales periodos son independientes de la distancia en el caso dePa pero crecen con ella paraSa. Las fasesPa ySa mejor desarrolladas se obtienen para terremotos cuya profundidad focal es inferior a los 60 kilómetros. El movimiento de la particula del suelo debido aSa puede ser de cualquier tipo, desde puroSV a puroSH, y muestra gran correlación con el movimiento de la particula deS. Los ángulos de emergencia aparentes (de promedio 51° paraPa y 54° paraSa) varian con la distancia. Basándonos en nuestras observaciones sugerimos quePa ySa se propagan por reflexión múltiple, bajo incidencia rozante bajo la discontinuidad de Mohorovii.

     

Direct measurement of crustalP-velocities in the norsar area

Using simulated data, it is demonstrated that one may estimate the body wave velocity in the crust by measuring the angle of incidence ofP-waves provided only the very first part of the signal is used. This angle has been measured for a set ofP-waves at the NORSAR long period instrument sites. Combining these observations with measurements of apparent velocities, we find that the data indicates a crust velocity of 6.1±0.4 km/sec. While it is somewhat uncertain to what depth the value is representative, the observations are in obvious disagreement with previous authors who concluded that long periodP-waves were not affected by the earth's crust. Because of difficulties in separating the effects of real velocity variations from measurement errors, the details of the observedP-wave variation across the array are difficult to interpret. The consistent behavior of the data does, however, indicate that variations of approximately 3% must exist in the crustalP-wave velocity across the array.     

High-speed correction factor to the O+-O resonance charge exchange collision frequency

The high-speed correction factor to the O⁺-O collision frequency, resulting from drift velocities between ions and neutrals, is calculated by solving the integral expression in this factor both numerically and analytically. Although the analytic solution is valid for either small or large drift velocities between ions and neutrals, for temperatures of interest and all drift velocities considered, agreement is found between analytic and detailed numerical integration results within less than 1% error. Let T _r designate the average of the ion and neutral temperatures in K, and u=v _d /<alpha>, where v _d is the relative drift velocity in cm s^?1, and <alpha>=4.56×10³\sqrtT _r cm s^?1 is the thermal velocity of the O⁺-O system. Then, as u ranges from 0 to 2, the correction factor multiplying the collision frequency increases monotonically from 1 to about 1.5. An interesting result emerging from this calculation is that the correction factor for temperatures of aeronomical interest is to a good approximation independent of the temperature, depending only on the scaled velocity u.     

Average crustal structure of Sweden

Summary Records obtained at the permanent stations of the Swedish seismograph network from explosions carried out in Scandinavian waters in June 1969 are evaluated. The study includes determination of velocities for all crustal phases observed, furthermore of layer thicknesses, Poisson ratios and amplitude ratios. The purpose of the study is partly to provide a first approximation to the crustal structure in Sweden, partly to provide regional data for location of earthquakes and explosions in the area in the future. Average velocities (km/sec) are forPn 7.88±0.05,Pg1 6.25±0.08,Pg2 5.70,Sn 4.58±0.04,S ^* 3.70±0.04,Sg1 (Lg1) 3.58±0.03,Sg2 (Sg) 3.40±0.03,Rg 3.02±0.07. The average thickness is 12 km for the granitic layer, and 23 km for the basaltic layer, thus making the average crustal thickness equal to 35 km. Relative amplitudes plotted versus distance complete the dynamical side of the study and they are useful for identification of waves. A regional travel-time table is presented for the distance range 0°–10° with entries for each 0.1° and including all crustal phases read.