Seismic P-wave receiver function modelling of Archean cratonic crust: A global perspective

Mapping Intimacies ◽

10.5194/egusphere-egu2020-9666 ◽

2020 ◽

Author(s):

Poulami Roy ◽

Kajaljyoti Borah

Keyword(s):

Continental Crust ◽

Receiver Function ◽

Function Analysis ◽

Crustal Thickness ◽

Global Perspective ◽

P Wave ◽

Evolution Process ◽

S Wave ◽

Economic Significance ◽

Formation And Evolution

<p>Cratons are representative of the oldest cores of continental crusts. Study of cratons is important &#160;as they preserve the pristine nature of continental crusts as well as they have economic significance as a major source of the world's mineral deposits. The crustal thickness, crustal composition, structure and physical properties of crust-mantle transition (the Moho) are the key parameters for understanding the formation and evolution of continental crust. The ratio of &#160;seismic P-wave and S-wave velocity (Vp/Vs) is used as a parameter to understand the petrologic nature of the Earth's crust. Using these parameters, we address the crustal properties of all Archean cratons. The teleseismic P-wave receiver function analysis reveals that all the Eoarchean (4-3.6 Ga) cratons (Superior, North Atlantic Craton, North China Craton, Yilgarn, Zimbabwe, Kaapvaal) have crustal thickness ranges between 34-42 km and Vp/Vs ratio 1.68-1.79, the Paleoarchean (3.6-3.2 Ga) cratons (Baltic shield, Pilbara, Tanzania, Grunehogna) have 29-52 km crustal thickness and Vp/Vs ratio 1.7-1.85, the Mesoarchean (3.2-2.8 Ga) cratons (Sao Francisco, Guapore, Yangtze, Antananarivo) have 36-53 km thickness and Vp/Vs ratio 1.7-1.9, and Neoarchean (2.8-2.5 Ga) cratons (Guiana, Anabar, Gawler, Napier, Tarim) have 36-59 km thickness and Vp/Vs ratio 1.64-1.95. The nature of crust-mantle transition is overall sharp and flat. &#160;We also found that the crusts which are stabilized earlier, are thinner compared to the later stabilized crusts. Our findings are well-correlated with the craton evolution process predicted by Durrheim and Mooney (1994), where older crusts are thin due to delamination process and relatively younger crusts are thick due to basaltic underplating. Our result of higher Vp/Vs ratio in the relatively younger crusts corroborates with the mafic nature of the crust whereas the older crusts are felsic-intermediate resulting lower Vp/Vs ratio. Our study is unique as it includes most of the global cratons and suggests a global model of continental crust formation and evolution process.</p>

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

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2013-0147 ◽

2014 ◽

Vol 51 (4) ◽

pp. 407-417 ◽

Cited By ~ 2

Author(s):

H.S. Kim ◽

J.F. Cassidy ◽

S.E. Dosso ◽

H. Kao

Keyword(s):

Wave Velocity ◽

Crustal Structure ◽

Velocity Structure ◽

Receiver Function ◽

Function Analysis ◽

Crustal Thickness ◽

Receiver Functions ◽

S Wave ◽

Low Velocity ◽

Velocity Models

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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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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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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Unexpected Consequences of Transverse Isotropy

Bulletin of the Seismological Society of America ◽

10.1785/0120200205 ◽

2020 ◽

Author(s):

Hitoshi Kawakatsu

Keyword(s):

Rayleigh Wave ◽

Wave Velocity ◽

Seismic Analysis ◽

Receiver Function ◽

Function Analysis ◽

Incidence Angle ◽

Body Wave ◽

Transverse Isotropy ◽

P Wave ◽

S Wave

ABSTRACT In a series of articles, Kawakatsu et al. (2015) and Kawakatsu (2016a,b, 2018) introduced and discussed a new parameter, ηκ, that characterizes the incidence angle dependence (relative to the symmetry axis) of seismic body-wave velocities in a transverse isotropy (TI) system. During the course of these exercises, several nontrivial consequences of TI were realized and summarized as follows: (1) P-wave velocity (anisotropy) strongly influences the conversion efficiency of P-to-S and S-to-P, as much as S-wave velocity perturbation does; (2) Rayleigh-wave phase velocity has substantial sensitivity to P-wave anisotropy near the surface; (3) a trade-off exists between ηκ and the VP/VS ratio if the latter is sought under an assumption of isotropy or the elliptic condition. Among these findings, the first two deserve careful attention in interpretation of results of popular seismic analysis methods, such as receiver function analysis and ambient-noise Rayleigh-wave dispersion analysis. We present simple example cases for such problems to delineate the effect in actual situations, as well as scalings among TI parameters of the crust and mantle materials or models that might help understanding to what extent the effect becomes important.

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The CIELO Seismic Experiment

Seismological Research Letters ◽

10.1785/0220210237 ◽

2021 ◽

Author(s):

Heather A. Ford ◽

Maximiliano J. Bezada ◽

Joseph S. Byrnes ◽

Andrew Birkey ◽

Zhao Zhu

Keyword(s):

Receiver Function ◽

Function Analysis ◽

P Wave ◽

Crust And Upper Mantle ◽

Waveform Data ◽

Wyoming Craton ◽

Sensor Orientation ◽

Seismic Experiment ◽

Short Period ◽

Receiver Function Analysis

Abstract The Crust and lithosphere Investigation of the Easternmost expression of the Laramide Orogeny was a two-year deployment of 24 broadband, compact posthole seismometers in a linear array across the eastern half of the Wyoming craton. The experiment was designed to image the crust and upper mantle of the region to better understand the evolution of the cratonic lithosphere. In this article, we describe the motivation and objectives of the experiment; summarize the station design and installation; provide a detailed accounting of data completeness and quality, including issues related to sensor orientation and ambient noise; and show examples of collected waveform data from a local earthquake, a local mine blast, and a teleseismic event. We observe a range of seasonal variations in the long-period noise on the horizontal components (15–20 dB) at some stations that likely reflect the range of soil types across the experiment. In addition, coal mining in the Powder River basin creates high levels of short-period noise at some stations. Preliminary results from Ps receiver function analysis, shear-wave splitting analysis, and averaged P-wave delay times are also included in this report, as is a brief description of education and outreach activities completed during the experiment.

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Common-Reflection-Point-Based Prestack Depth Migration for Imaging Lithosphere in Python: Application to the Dense Warramunga Array in Northern Australia

Seismological Research Letters ◽

10.1785/0220200078 ◽

2020 ◽

Vol 91 (5) ◽

pp. 2890-2899 ◽

Cited By ~ 1

Author(s):

Weijia Sun ◽

Brian L. N. Kennett

Keyword(s):

Open Source ◽

Receiver Function ◽

Function Analysis ◽

Vertical Component ◽

P Wave ◽

Northern Australia ◽

Reflection Point ◽

Prestack Depth Migration ◽

Depth Migration ◽

Conversion Point

Abstract We exploit estimates of P-wave reflectivity from autocorrelation of transmitted teleseismic P arrivals and their coda in a common reflection point (CRP) migration technique. The approach employs the same portion of the vertical-component seismogram, as in standard Ps receiver function analysis. This CRP prestack depth migration approach has the potential to image lithospheric structures on scales as fine as 4 km or less. The P-wave autocorrelation process and migration are implemented in open-source software—the autocorrelogram calculation (ACC) package, which builds on the widely used the seismological Obspy toolbox. The ACC package is written in the open-source and free Python programming language (3.0 or newer) and has been extensively tested in an Anaconda Python environment. The package is simple and friendly to use and runs on all major operating systems (e.g., Windows, macOS, and Linux). We utilize Python multiprocessing parallelism to speed up the ACC on a personal computer system, or servers, with multiple cores and threads. The application of the ACC package is illustrated with application to the closely spaced Warramunga array in northern Australia. The results show how fine-scale structures in the lithospheric can be effectively imaged at relatively high frequencies. The Moho ties well with conventional H−κ receiver analysis and deeper structure inferred from stacked autocorrelograms for continuous data. CRP prestack depth migration provides an important complement to common conversion point receiver function stacks, since it is less affected by surface multiples at lithospheric depths.

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Structure of the crust and upper mantle of the Great Slave Lake shear zone, northwestern Canada, from teleseismic analysis and gravity modelling

Canadian Journal of Earth Sciences ◽

10.1139/e03-038 ◽

2003 ◽

Vol 40 (9) ◽

pp. 1203-1218 ◽

Cited By ~ 17

Author(s):

David W Eaton ◽

Jacqueline Hope

Keyword(s):

Shear Zone ◽

Upper Mantle ◽

Receiver Function ◽

Function Analysis ◽

Crustal Material ◽

S Wave ◽

Crust And Upper Mantle ◽

Fast Axis ◽

Great Slave Lake ◽

Basic Features

The Great Slave Lake shear zone (GSLsz) exposes lower crustal rocks analogous to deep-seated segments of modern strike-slip fault zones, such as the San Andreas fault. Extending for 1300 km beneath the Western Canada Sedimentary Basin to the southern margin of the Slave Province, the GSLsz produces one of the most prominent linear magnetic anomalies in Canada. From May to October 1999, 13 three-component portable broadband seismograph stations were deployed in a 150-km profile across a buried segment of the shear zone to investigate its lithospheric structure. Splitting analysis of core-refracted teleseismic shear waves reveals an average fast-polarization direction (N49°E ± 19°) that is approximately parallel to the shear zone. Individual stations near the axis of the shear zone show more northerly splitting directions, which we attribute to interference between regional anisotropy in the upper mantle (fast axis ~N60°E) and crustal anisotropy within the shear zone (fast axis ~N30°E). At the location of our profile, the shear zone is characterized by a 10-mGal axial gravity high with a wavelength of 30 km, superimposed on a longer wavelength 12-mGal low. This gravity signature is consistent with the basic features of the crustal model derived from receiver-function analysis: a Moho that dips inward toward the shear-zone axis and a mid-crustal zone with high S-wave velocity (ΔVs = 0.6 ± 0.2 km/s). The axial gravity high may be related to uplift of deeper crustal material within the shear zone, or protolith-dependent compositional differences between the shear zone and surrounding wall rocks.

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