The CIELO Seismic Experiment

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.

Sensor Orientation of Iranian Broadband Seismic Stations from P-Wave Particle Motion

2020 ◽  
Vol 91 (3) ◽  
pp. 1660-1671 ◽  
Author(s):  
Jochen Braunmiller ◽  
John Nabelek ◽  
Abdolreza Ghods
Keyword(s):  
Receiver Function ◽  
Function Analysis ◽  
Source Parameters ◽  
Transverse Component ◽  
P Wave ◽  
Seismic Stations ◽  
Waveform Modeling ◽  
Seismic Waveforms ◽  
Sensor Orientation ◽  
Receiver Function Analysis

Abstract Knowing the orientation of horizontal components of seismic sensors is important for many seismological applications such as waveform modeling, receiver function analysis, and shear-wave splitting. We determined the sensor orientations for broadband seismic stations belonging to the Iranian National Seismic Network (INSN) and the Iranian Seismological Center (IRSC) to enable such studies. For both networks, we have catalogs of event-based seismic waveforms of Iranian earthquakes. Sensor orientations were found by P-wave energy minimization on the transverse component and validated by long-period waveform modeling of events with well-constrained source parameters. We obtained stable sensor orientations for 28 (of 29) INSN sites and for 66 (of 92) IRSC sites. About 75% and 59% of all INSN and IRSC orientation estimates, respectively, are oriented within 15° of true north leaving many sites with largely misoriented sensors. We found temporally changing sensor orientations for 36 (of 121) sites.

Receiver function analysis reveals layered anisotropy in the crust and upper mantle beneath southern Peru and northern Bolivia

2019 ◽  
Vol 753 ◽  
pp. 93-110 ◽  
Author(s):  
Neta Bar ◽  
Maureen D. Long ◽  
Lara S. Wagner ◽  
Susan L. Beck ◽  
George Zandt ◽  
...  
Keyword(s):  
Upper Mantle ◽  
Receiver Function ◽  
Function Analysis ◽  
Crust And Upper Mantle ◽  
Southern Peru ◽  
Receiver Function Analysis

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

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.

Investigation of crustal structure in Nias Island, Sumatra using P-wave receiver function analysis

2020 ◽  
Author(s):  
Frilla R. T. Saputra ◽  
Syuhada Syuhada ◽  
Titi Anggono ◽  
Mohammad S. Rosid
Keyword(s):  
Crustal Structure ◽  
Receiver Function ◽  
Function Analysis ◽  
P Wave ◽  
Receiver Function Analysis

Preliminary results from teleseismic tomography of the upper mantle beneath northern Borneo

2020 ◽  
Author(s):  
Simone Pilia ◽  
Nick Rawlinson ◽  
Felix Tongkul ◽  
Amy Gilligan ◽  
Dave Cornwell
Keyword(s):  
Upper Mantle ◽  
Receiver Function ◽  
Function Analysis ◽  
P Wave ◽  
The West ◽  
Tomographic Images ◽  
Teleseismic Tomography ◽  
North East ◽  
Receiver Function Analysis ◽  
Entire Network

<p>We present preliminary P-wave tomographic images of the upper mantle beneath northern Borneo (Sabah) using teleseismic earthquake data. Sabah underwent diachronous double-polarity subduction, one dipping to the southeast (terminated in the early Miocene) and the other to the northwest (terminated 5-6 Ma). With the goal of better understanding post-subduction processes in Sabah, 24 permanent seismic stations of MetMalaysia were augmented by the deployment of 46 temporary stations of the nBOSS network, which ran from March 2018 to January 2020. Relative P-wave traveltime residuals from nearly a thousand teleseismic events have been extracted from the continuous records using an adaptive stacking technique, which uses the coherency of global phases across the entire network. Using a grid-based eikonal solver and a subspace inversion technique implemented in FMTOMO, relative arrival time residuals are mapped as 3-D P-wave perturbations.</p><p>The most intriguing feature of the final tomographic model is a north-east trending lithospheric structure running across northern Borneo and separating relatively low to high wavespeeds to the west and east, respectively. This structure possibly indicates the suture between pre-Cenozoic lithosphere to the east and the Cenozoic accreted material to the west.</p><p>Results from receiver function analysis (i.e., crustal thickness) and crustal velocities from ambient noise tomography will be in the future incorporated in the tomographic inversion in order to obtain an integrated view of the crust-mantle system beneath Sabah.</p>

Structure of crust and upper mantle beneath the Ordos Block and the Yinshan Mountains revealed by receiver function analysis

2011 ◽  
Vol 184 (3-4) ◽  
pp. 186-193 ◽  
Author(s):  
Xiaobo Tian ◽  
Jiwen Teng ◽  
Hongshuang Zhang ◽  
Zhongjie Zhang ◽  
Yongqian Zhang ◽  
...  
Keyword(s):  
Upper Mantle ◽  
Receiver Function ◽  
Function Analysis ◽  
Crust And Upper Mantle ◽  
Ordos Block ◽  
Receiver Function Analysis

Receiver function analysis for determining the crustal structure of Tenerife (Canary Islands, Spain)

2020 ◽  
Author(s):  
Víctor Ortega ◽  
Luca D'Auria
Keyword(s):  
Oceanic Crust ◽  
Arrival Time ◽  
Receiver Function ◽  
Function Analysis ◽  
Volcanic Rocks ◽  
Thick Layer ◽  
Receiver Functions ◽  
P Wave ◽  
Crustal Structures ◽  
Receiver Function Analysis

<p>The receiver function analysis (RF) is a commonly used and well-established method to investigate subsurface crustal and upper mantle structures, removing the source, ray-path and instrument signatures. RF gives the unique signature of sharp seismic discontinuities and information about P-wave (P) and shear-wave (Ps) velocity below the seismic station. In particular using the direct P-wave as a known reference arrival time, and the relative arrival time of P-to-S (Ps) conversions as well as PpPs, PsPs and PsSs reflections allow constraining the principal crustal structures and allows us to study the effects of dipping interfaces and crustal layering.</p><p>The aim of this work is to use the RF non-conventional analysis to study the crustal structures of Tenerife. Previous studies on receiver functions analysis an active oceanic volcanic island, showed that the Moho topography have a high dipping under the volcanic edifice and a depth ranging between 11 and 18 km depth. Furthermore, it has been observed that some phases related with a layer of volcanic rocks having a thickness of about 5.5 km and a P-wave velocity (Vp) of approximately 6 Km/s, lies above an old oceanic crust having a thickness of about 7 km and a Vp of about 6.8 km/s.</p><p>For this study we applied both time and frequency domain deconvolution to obtain receiver functions. The determination of the average crustal thickness and has been achieved by using the commonly uses H-k method. To constrain the internal crustal layering, we used a non-linear inversion algorithm based on full waveform modeling of the receiver function. Finally, we realized a modelling of the reflected and converted phases in the crust using seismic ray tracing. Our modelling takes into account the surface topography as well as an arbitrary geometry of the Moho.</p><p>In conclusion our results showed the presence of a thick layer (up to 5.5 km) of volcanic rocks in the central part of the island overlying an oceanic crust whose total thickness varied from 18 km in the central part to about 11 km in the peripheral areas. This work represents the first step toward further studies devoted at a finer imaging of the crustal structures of Tenerife using receiver function analysis.</p>

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