Mapping crustal structure of the Nechako–Chilcotin plateau using teleseismic receiver function analysis,

This paper presents results of a passive-source seismic mapping study in the Nechako–Chilcotin plateau of central British Columbia, with the ultimate goal of contributing to assessments of hydrocarbon and mineral potential of the region. For the present study, an array of nine seismic stations was deployed in 2006–2007 to sample a wide area of the Nechako–Chilcotin plateau. The specific goal was to map the thickness of the sediments and volcanic cover, and the overall crustal thickness and structural geometry beneath the study area. This study utilizes recordings of about 40 distant earthquakes from 2006 to 2008 to calculate receiver functions, and constructs S-wave velocity models for each station using the Neighbourhood Algorithm inversion. The surface sediments are found to range in thickness from about 0.8 to 2.7 km, and the underlying volcanic layer from 1.8 to 4.7 km. Both sediments and volcanic cover are thickest in the central portion of the study area. The crustal thickness ranges from 22 to 36 km, with an average crustal thickness of about 30–34 km. A consistent feature observed in this study is a low-velocity zone at the base of the crust. This study complements other recent studies in this area, including active-source seismic studies and magnetotelluric measurements, by providing site-specific images of the crustal structure down to the Moho and detailed constraints on the S-wave velocity structure.

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Crustal Structure Study in Lampung Region Using Teleseismic Receiver Function Analysis

Journal of Physics Conference Series ◽

10.1088/1742-6596/2110/1/012002 ◽

2021 ◽

Vol 2110 (1) ◽

pp. 012002

Author(s):

A R Puhi ◽

P Ariyanto ◽

B Pranata ◽

B S Prayitno

Keyword(s):

Wave Velocity ◽

Crustal Structure ◽

Receiver Function ◽

Function Analysis ◽

P Wave ◽

Sediment Layer ◽

Eurasian Plate ◽

S Wave ◽

Near Surface ◽

Sumatran Fault

Abstract Lampung region is seismically and volcanic active because located in subduction zone of Indo-Australian and Eurasian plate. We applied receiver function and stacking H-k analysis to estimate the crustal structure in Lampung region. We used teleseismic earthquake data (epicenter distance 30°-90°) and M>6 recorded at 3 seismic broadband stations owned by Agency for Meteorology Climatology and Geophysics (BMKG). Those stations are PSLI (located on Sebesi Island approximately 20 km from Anak Krakatau) represented volcanic arc zone, KASI (located on Kota Agung, Lampung) represented Sumatran Fault Zone and KLI (located on Kotabumi, Lampung) represented back-arc basin. Crustal thickness estimated at PSLI station 32-36 km, KASI station 36-40 km, and KLI station 30-36 km. Furthermore, in 3 stations P wave velocity estimated 4.1-11 km/s, S wave velocity 2.2-6.2 km/s, while vp/vs value estimated 1.7-2.05. We estimated Anak Krakatau volcano’s magma chamber beneath PSLI station in depth 16-30 km, Great Sumatran Fault structure in depth about 8-14 km beneath KASI station, and thick sediment layer about 4 km near surface beneath KLI station. This study result is expected to explain more detail crustal of Lampung region and can be useful for developing of BMKG’s seismic monitoring systems and other geophysical fields in future.

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Joint inversion of receiver functions and apparent incidence angles to investigate the crustal structure of Mars

10.5194/egusphere-egu21-9470 ◽

2021 ◽

Author(s):

Rakshit Joshi ◽

Brigitte Knapmeyer-Endrun ◽

Klaus Mosegaard ◽

Felix Bissig ◽

Amir Khan ◽

...

Keyword(s):

Wave Velocity ◽

Crustal Structure ◽

Joint Inversion ◽

Landing Site ◽

Crustal Thickness ◽

Receiver Functions ◽

P Wave ◽

S Wave ◽

Data Set ◽

Insight Mission

<p>Since InSight (the Interior Exploration using Geodesy and Heat Transport) landed 26 months ago and deployed an ultra sensitive broadband seismometer(SEIS) on the surface of Mars, around 500 seismic events of diverse variety have been detected, making it possible to directly analyze the subsurface properties of Mars for the very first time. One of the primary goals of the mission is to retrieve the crustal structure below the landing site. Current estimates differ by more than 100% for the average crustal thickness. Since data from orbital gravity measurementsprovide information on relative variations of crustal thickness but not absolute values, this landing site measurement could serve as a tie point to retrieve global crustal structure models. To do so, we propose using a joint inversion of receiver functions and apparent incidence angles, which contain information on absolute S-wave velocities of the subsurface. Since receiver function inversions suffer from a velocity depth trade-off, we in addition exploit a simple relation which defines apparent S-wave velocity as a function of observed apparent P-wave incidence angles to constrain the parameter space. Finally we use the Neighbourhood Algorithm for the inversion of a suitable joint objective function. The resulting ensemble of models is then used to derive the full uncertainty estimates for each model parameter. Before its application on data from InSight mission, we successfully tested the method on Mars synthetics and terrestrial data from various geological settings using both single and multiple events. Using the same method, we have previously been able to constrain the S-wave velocity and depth for the first inter-crustal layer of Mars between 1.7 to 2.1 km/s and 8 to 11 km, respectively. Here we present the results of applying this technique on our selected data set from the InSight mission. Results show that the data can be explained equally well by models with 2 or 3 crustal layers with constant velocities. Due to the limited data set it is difficult to resolve the ambiguity of this bi-modal solution. We therefore investigate information theoretic statistical tests as a model selection criteria and discuss their relevance and implications in seismological framework.</p><div></div><div></div><div></div>

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Lithospheric structure of the Arabian Shield from joint inversion of P- and S-wave receiver functions and dispersion velocities

Acta Geologica Polonica ◽

10.1515/agp-2015-0009 ◽

2015 ◽

Vol 65 (2) ◽

pp. 239-255 ◽

Cited By ~ 2

Author(s):

Abdullah M. Al-Amri

Keyword(s):

Green's Functions ◽

Velocity Structure ◽

Green’S Functions ◽

Joint Inversion ◽

Receiver Functions ◽

Gulf Of Aqaba ◽

Arabian Shield ◽

S Wave ◽

Velocity Models ◽

Seismic Networks

Abstract New velocity models of lithospheric thickness and velocity structure have been developed for the Arabian Shield by three tasks: 1) Computing P-Wave Receiver Functions (PRFs) and S-Wave Receiver Functions (SRFs) for all the broadband stations within the Saudi seismic networks. The number of receiver function waveforms depends on the recording time window and quality of the broadband station. 2) Computing ambient noise correlation Green’s functions for all available station pairs within the Saudi seismic networks to image the shear velocity in the crust and uppermost mantle beneath the Arabian Peninsula. Together they provided hundreds of additional, unique paths exclusively sampling the region of interest. Both phase and group velocities for all the resulting empirical Green’s functions have been measured and to be used in the joint inversion. 3) Jointly inverted the PRFs and SRFs obtained in task 1 with dispersion velocities measured on the Green’s functions obtained in task 2 and with fundamental-mode, Rayleigh-wave, group and phase velocities borrowed from the tomographic studies to precisely determine 1D crustal velocity structure and upper mantle. The analysis of the PRFs revealed values of 25-45 km for crustal thickness, with the thin crust next to the Red Sea and Gulf of Aqaba and the thicker crust under the platform, and Vp/Vs ratios in the 1.70-1.80 range, suggesting a range of compositions (felsic to mafic) for the shield’s crust. The migrated SRFs suggest lithospheric thicknesses in the 80-100 km range for portions of the shield close to the Red Sea and Gulf of Aqaba and near the Arabian Gulf. Generally, the novelty of the velocity models developed under this paper has consisted in the addition of SRF data to extend the velocity models down to lithospheric and sub-lithospheric depths.

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S-wave Velocity Structure Beneath the KS31 Seismic Station in Wonju, Korea Using the Joint Inversion of Receiver Functions and Surface-wave Dispersion Curves and the H-κ Stacking Method

Geophysics and Geophysical Exploration ◽

10.7582/gge.2012.15.1.008 ◽

2012 ◽

Vol 15 (1) ◽

pp. 8-15 ◽

Cited By ~ 2

Author(s):

Tae-Hyeon Jeon ◽

Ki-Young Kim ◽

Yong-Cheol Park ◽

Ik-Bum Kang

Keyword(s):

Surface Wave ◽

Wave Velocity ◽

Velocity Structure ◽

Joint Inversion ◽

Seismic Station ◽

Wave Dispersion ◽

Receiver Functions ◽

Dispersion Curves ◽

S Wave ◽

Surface Wave Dispersion

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The crust and uppermost mantle s-wave velocity structure beneath japan islands revealed by joint analysis of p-and s-wave receiver functions

Malaysian Journal of Geosciences ◽

10.26480/mjg.02.2017.20.23 ◽

2017 ◽

Vol 1 (2) ◽

pp. 20-23 ◽

Cited By ~ 9

Author(s):

Jun Wang ◽

Hongtai xu

Keyword(s):

Wave Velocity ◽

Velocity Structure ◽

Receiver Functions ◽

Joint Analysis ◽

S Wave ◽

Uppermost Mantle

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Observation of Higher-Mode Surface Waves from an Active Source in the Hutubi Basin, Xinjiang, China

Bulletin of the Seismological Society of America ◽

10.1785/0120200272 ◽

2021 ◽

Author(s):

Zhanbo Ji ◽

Baoshan Wang ◽

Wei Yang ◽

Weitao Wang ◽

Jinbo Su ◽

...

Keyword(s):

Surface Waves ◽

Wave Velocity ◽

Seismic Waves ◽

Velocity Structure ◽

Group Velocity Dispersion ◽

S Wave ◽

Contributing Factors ◽

Low Velocity ◽

Time Frequency ◽

Wave Modes

ABSTRACT Basins with thick sediments can amplify and prolong the incoming seismic waves, which may cause serious damage to surface facilities. The amplification of seismic energy depends on the shear-wave velocity of the uppermost layers, which is generally estimated through surface wave analysis. Surface waves may propagate in different modes, and the mechanism of the mode development is not well understood. Exploiting a recently deployed permanent airgun source in the Hutubi basin, Xinjiang, northwest China, we conducted a field experiment to investigate the development of multimode surface waves. We observed surface waves at the frequency of 0.3–5.0 Hz with apparent group velocities of 200–900 m/s, and identified five modes of surface waves (three Rayleigh-wave modes and two Love-wave modes) through time–frequency and particle-motion analyses. We then measured 125 group velocity dispersion curves of the fundamental- and higher-mode surface waves, and further inverted the 1D S-wave velocity structure of the Hutubi basin. The S-wave velocity increases abruptly from 238 m/s at the surface to 643 m/s at 300 m depth. Synthetic seismograms with the inverted velocity structure capture the main features of the surface waves of the different modes. Synthetic tests suggest that the low velocity, high velocity gradient, and shallow source depth are likely the dominant contributing factors in the development of higher-mode surface waves.

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Imaging the Moho and Main Himalayan Thrust beneath the Kumaon Himalaya: constraints from receiver function analysis

Geophysical Journal International ◽

10.1093/gji/ggaa478 ◽

2020 ◽

Vol 224 (2) ◽

pp. 858-870

Author(s):

Devajit Hazarika ◽

Somak Hajra ◽

Abhishek Kundu ◽

Meena Bankhwal ◽

Naresh Kumar ◽

...

Keyword(s):

Poisson’S Ratio ◽

Receiver Function ◽

Function Analysis ◽

Crustal Thickness ◽

Receiver Functions ◽

P Wave ◽

Poisson's Ratio ◽

Kumaon Himalaya ◽

Receiver Function Analysis ◽

Lower Crustal

SUMMARY We analyse P-wave receiver functions across the Kumaon Himalaya and adjoining area to constrain crustal thickness, intracrustal structures and seismic velocity characteristics to address the role of the underlying structure on seismogenesis and geodynamic evolution of the region. The three-component waveforms of teleseismic earthquakes recorded by a seismological network consisting of 18 broad-band seismological stations have been used for receiver function analysis. The common conversion point (CCP) depth migrated receiver function image and shear wave velocity models obtained through inversion show a variation of crustal thickness from ∼38 km in the Indo-Gangetic Plain to ∼42 km near the Vaikrita Thrust. A ramp (∼20°) structure on the Main Himalayan Thrust (MHT) is revealed beneath the Chiplakot Crystalline Belt (CCB) that facilitates the exhumation of the CCB. The geometry of the MHT observed from the receiver function image is consistent with the geometry revealed by a geological balanced cross-section. A cluster of seismicity at shallow to mid-crustal depths is detected near the MHT ramp. The spatial and depth distribution of seismicity pattern beneath the CCB and presence of steep dipping imbricate faults inferred from focal mechanism solutions suggest a Lesser Himalayan Duplex structure in the CCB above the MHT ramp. The study reveals a low-velocity zone (LVZ) with a high Poisson's ratio (σ ∼0.28–0.30) at lower crustal depth beneath the CCB. The high value of Poisson's ratio in the lower crust suggests the presence of fluid/partial melt. The shear heating in the ductile regime and/or decompression and cooling associated with the exhumation of the CCB plausibly created favorable conditions for partial melting in the lower crustal LVZ.

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