bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strong ground motion from the Uttarkashi, Himalaya, India, earthquake: Comparison of observations with synthetics using the composite source model
Authors: Yu G. , Khattri K. N. , Anderson J. G. , Brune J. N. , Zeng Y. 
Published: September 2021

Abstract
The Uttarkashi earthquake of 19 October 1991 (MS = 7.0) occurred in the greater Himalayan region north of the main central thrust, at an estimated depth of 12 km. The fault plane solution indicates a low-angle thrust mechanism, striking northwest, consistent with the tectonic pattern of thrusting in the region. Aftershocks define a belt parallel to, and north of, the surface trace of the main central thrust, roughly 10-km wide and 30-km long. The mainshock is located at the northeast edge of this zone. The earthquake was recorded on 13 strong-motion accelerographs at distances ranging from 25 to 150 km from the epicenter. One station at Bhatwari (peak horizontal acceleration of 272 cm sec−2) is above the aftershock zone. The maximum peak horizontal acceleration was about 313 cm sec−2 at Uttarkashi, at an epicentral distance of 36 km.
The amplitudes and frequency content of the strong ground motions are more or less consistent with expectations for an earthquake of this magnitude in California. Synthetics generated using the composite source model and synthetic Green's functions (Zeng et al., 1994a, b) are successful in producing acceleration, velocity, and displacement with a realistic appearance and the correct statistical properties of the two accelerograms recorded nearest the fault (Bhatwari and Uttarkashi). To produce these, we introduced trial-and-error modifications of the layered-medium velocity model within uncertainties. At more distant stations, we first used the velocity structure that worked for the two nearest stations. Differences emphasize the large potential role of unknown site and wave-propagation effects. For the station at Tehri, we explored different velocity models, and found one there that was also quite successful. We then used these two velocity models to predict strong ground motions at Bhatwari and Tehri, from a potential magnitude 8.5 earthquake filling part of the seismic gap along the Himalayan frontal faults. The synthetics show peak accelerations that are only somewhat larger than those in the Uttarkashi event, but much longer durations and increased amplitudes of response spectra at long periods.
Observations of Q from the northwest Pacific subduction zone recorded at teleseismic distances
Authors: Sharrock D. S. , Main I. G. , Douglas A. 
Published: September 2021

Abstract
Twenty-seven earthquakes in the northwest Pacific, with mb ≧ 5.4, are used to study upper-mantle attenuation. The data were recorded at seismometer arrays in Australia, Canada, India, and Scotland. The short-period instruments used in the arrays are sufficiently broadband, and the signal-to-noise enhancement resulting from beamforming the data is good enough, that seismic noise is above system noise out to between 3 and 5 Hz, and in some cases to 8 Hz. The instrument response has been removed and a power law (ω−2) farfield source correction has been assumed and applied. The remaining fall-off in the spectra above 1 Hz (which is above the corner frequency fc) is assumed to be due to attenuation, including losses due both to anelasticity and to scattering. An ω−3 spectral fall-off, preferred by some, would result in lower estimates of attenuation. Conservative estimates of the average attenuation along the whole path have been made from the spectral fall-off. Despite the imperfect knowledge of the source spectra, the high sensitivity of spectral amplitudes to attenuation at high frequencies yields quite reliable and stable attenuation estimates. The scatter in the data is small, resulting in estimates of mean t* (tAV*) with an average standard error of only 21%, where tAV* is defined as the ratio of the travel time T to the effective mean quality factor QAV. Only 14 of the 64 measurements show a tAV* above 0.5 sec within the given error bounds. All estimates of tAV* and QAV refer to P-wave attenuation only. The results for tAV* from the northwest Pacific subduction zone cannot be explained simply by the traditional high-Q subducting slab in a low-Q upper mantle. A low-Q region in the uppermost 100 km (approximately) of the subduction zone has been identified. Source-corrected tAV* yield upper-mantle QAV estimates of about 1200 for predominantly oceanic paths (Australia and India) and 1500 for mixed continental and oceanic paths (Canada and Scotland).
Dipping structure under Dourbes, Belgium, determined by receiver function modeling and inversion
Authors: Zhang Jie , Langston Charles A. 
Published: September 2021

AbstractTeleseismic broadband P and S waves recorded at the NARS station NE06 (Dourbes, Belgium) are shown to exhibit strong anomalous particle motion not attributable to instrument miscalibration or malfunction. Azimuthally varying radial and tangential components have been observed on 38 recordings after vector rotation of horizontal P waves into the ray direction. The tangenital P waves attain amplitudes comparable to the radial components from the east with negative polarity and west with positive polarity, but tend to be zero in the north and south, suggesting major discontinuities in the crust dipping southward. The SH wave from the east contains a large SPmP phase, an S-to-P conversion at the free surface and then reflected back to the surface from the Moho. The polarity of this SPmP phase presents further evidence for a southward-dipping Moho.We employ ray theory for three-dimensionally dipping interfaces to compute the P-wave response. Linear inverse theory with smoothness constraints is applied to the simultaneous inversions of P-wave receiver functions for four different backazimuths. Through the progressive change of interface strike and dip and the inversion of layer shear-wave velocities, a dipping crustal model that is consistent with both the observed waveforms and results of previous local geophysical surveys has been determined. The results suggest a large velocity contrast in the shallow structure near the surface, another major interface at a depth of 12 km with dip of 10°, and a seismically transparent unit below the interface. The interface at a depth of 12 km reportedly emerges at the Midi fault 50 km north of the station NE06.
Determination of earthquake source parameters using a hybrid global search algorithm
Authors: Hartzell Stephen , Liu Pengcheng 
Published: September 2021

AbstractA hybrid global optimization algorithm using a combination of simulated annealing and downhill simplex methods is used to invert teleseismic body waves for earthquake source parameters. Time-domain constraints on the source-time function, inversion for double-couple parameters rather than moment tensor elements, and consideration of multiple sources lead to a nonlinear and multimodal problem, in which the objective function contains many local minima. Traditional approaches that linearize the problem and use iterative least squares are dependent on the starting model and the order in which multiple sources are processed, and can converge to a local minimum. Also, grid searches are impractical for the number of parameters we treat simultaneously. The hybrid global method provides an attractive alternative because it converges to the global minimum of a prescribed objective function and can be used to invert for multiple sources simultaneously. Model parameter constraints are easy to incorporate into the global search process, if they are desired.A multiple point-source parameterization of the 1992 Landers, California, earthquake is used as an example of the inversion method. Rupture in this earthquake occurred along three main fault segments: the Johnson Valley fault, the Homestead fault, and the Emerson/Rock Creek faults. We invert for the strike, dip, and rake of each source, the time separation of the sources, and the farfield source-time function of each source. Parameters obtained from the inversion are consistent with field observations and the results of other investigations. Strikes vary consistently with the trend of the surface ruptures. The dip is near 90° along the entire length of the rupture, and the rake is nearly pure right-lateral strike slip. The estimated moment is 7.6 × 1026 dyne-cm. The continuity of the moment release across the junction of the Homestead and Emerson faults suggests that these two faults may be more continuous at depth than at the surface. Moment release in the transition from the Johnson Valley to the Homestead faults is complex, indicating a complicated time history of faulting and a less direct relationship between the primary mapped faults.
A probabilistic approach to ground-motion selection for engineering design
Authors: Chapman Martin C. 
Published: September 2021

Abstract
The solutions of many earthquake engineering problems involve dynamic analyses using ground-motion time series. It is often desirable to base the selection of such motions on a probabilistic estimate of the seismic hazard. The hazard density function evaluated at a chosen hazard level provides the information necessary to determine objectively the most likely earthquake events, defined by magnitude and distance, that contribute to seismic hazard. For a wide range of hazard models it is possible to show that the difference between the median motion at a site, given the occurrence of the most likely event, and the motion value corresponding to a specified hazard level, is due entirely to the modeling of random error in the strong-motion data set. This points to a straightforward approach to selecting ground-motion recordings that represent the most likely time-domain realizations of the hazard model for a given motion parameter and hazard level. Ground-motion time series selection and/or synthesis based upon this approach, for various frequency bands of the response spectrum, can provide an optimum basis for seismic design.
Evaluation of local site effects and their removal from borehole records observed in the Sendai region, Japan
Authors: Satoh Toshimi , Kawase Hiroshi , Sato Toshiaki 
Published: September 2021

AbstractWe present results from a borehole observation network composed of 12 borehole sites deployed in a 20 × 20 km area in the Sendai region, Japan. The subsurface Quaternary layers vary with each site, but a Pliocene layer is commonly underlying at a depth of 0 to 80 m throughout the Sendai region. We define this Pliocene layer, whose S-wave velocity is larger than 500 m/sec and whose N value of the standard penetration test is greater than 50, as an engineering bedrock in the region. Once we characterize ground motions at the engineering bedrock, we can either use these motions directly in the response analysis of whole soil-building systems or use them in the nonlinear analysis of soft soil layers as an input. The purpose of this study is to evaluate the local site effects due to surface layers overlying the engineering bedrock and to remove them by using one-dimensional (1D) soil models whose properties are determined by weak-motion records of 18 events. First we identify S-wave velocities and frequency-dependent quality factors Q from amplification factors between surface records and borehole records observed at 10 sites at depths of several tens of meters. The identified S-wave velocities are very close to S-wave logging values. The identified Q values show strong frequency dependence, proportional to f(0.46 to 1.16), where f is frequency. We confirm that the observed amplification factors in the frequency range from about 0.1 to 20 Hz can be explained well by the theoretical ones based on the 1D wave propagation theory with the identified S-wave velocities and Q. Then we estimate the so-called engineering bedrock waves, which are supposed to be observed on the outcrop of the engineering bedrock, from borehole records by using the 1D models with these identified soil constants. We confirm that local site effects due to surface layers overlying the engineering bedrock are properly removed so that we have similar characteristics in the resultant engineering bedrock waves from records at different sites.
Nonlinear behavior of soil sediments identified by using borehole records observed at the Ashigra Valley, Japan
Authors: Satoh Toshimi , Sato Toshiaki , Kawase Hiroshi 
Published: September 2021

Abstract
We evaluate the nonlinear behavior of soil sediments during strong ground shaking based on the identification of their S-wave velocities and damping factors for both the weak and strong motions observed on the surface and in a borehole at Kuno in the Ashigara Valley, Japan. First we calculate spectral ratios between the surface station KS2 and the borehole station KD2 at 97.6 m below the surface for the main part of weak and strong motions. The predominant period for the strong motion is apparently longer than those for the weak motions. This fact suggests the nonlinearity of soil during the strong ground shaking. To quantify the nonlinear behavior of soil sediments, we identify their S-wave velocities and damping factors by minimizing the residual between the observed spectral ratio and the theoretical amplification factor calculated from the one-dimensional wave propagation theory. The S-wave velocity and the damping factor h (≈(2Q)−1) of the surface alluvial layer identified from the main part of the strong motion are about 10% smaller and 50% greater, respectively, than those identified from weak motions. The relationships between the effective shear strain (=65% of the maximum shear strain) calculated from the one-dimensional wave propagation theory and the shear modulus reduction ratios or the damping factors estimated by the identification method agree well with the laboratory test results. We also confirm that the soil model identified from a weak motion overestimates the observed strong motion at KS2, while that identified from the strong motion reproduces the observed. Thus, we conclude that the main part of the strong motion, whose maximum acceleration at KS2 is 220 cm/sec2 and whose duration is 3 sec, has the potential of making the surface soil nonlinear at an effective shear strain on the order of 0.1%. The S-wave velocity in the surface alluvial layer identified from the part just after the main part of the strong motion is close to that identified from weak motions. This result suggests that the shear modulus recovers quickly as the shear strain level decreases.
Penggunaan Smartphone di Kalangan Anak Petani Desa Pandan Sari kecamatan Tatah Makmur Kabupaten Banjar Provinsi Kalimantan Selatan
Authors: Sigit Ruswinarsih,Reski.P Abdul Rahman 
Published: September 2021

Pasar merupakan tempat bertemu antara penjual dan pembeli. Berbagai aktivitas jual beli dilakukan Penggunaan Smartphone marak digunakan berbagai kalangan usia mulai dari tua, muda sampai dengan anak-anak yang masih bersekolah. Penelitian ini bertujuan: (1) untuk mengetahui kebiasaan menggunakan Smartphone di kalangan anak petani. (2) untuk mendeskripsikan pengawasan orang tua kepada anak yang menggunakan Smartphone di Desa Pandan Sari. Metode penelitian yang digunakan adalah metode kualitatif. Sumber data dipilih dengan cara purposive sampling. Pengumpulan data dilakukan dengan teknik observasi, wawancara, dan dokumentasi. Analisis hasil penelitian menggunakan langkah-langkah reduksi data, penyajian data dan verifikasi data. Hasil penelitian menunjukkan bahwa: (1) kebiasaan menggunakan Smartphone di kalangan anak petani di Desa Pandan Sari terbagi menjadi tiga yaitu; untuk keperluan belajar, sarana hiburan dimana mereka bisa bermain game dan mengakses youtube, serta media komunikasi dimana Smartphone mereka pakai untuk melakukan komunikasi dengan guru dan teman melalui media sosial baik untuk keperluan sekolah ataupun lainnya. (2) pengawasan orang tua kepada anak yang menggunakan Smartphone di Desa Pandan Sari terbagi menjadi tiga yaitu; pendampingan, memberikan batasan, dan pemberian sanksi, cara orang tua memberikan sanksi kepada anak yang melanggar batasan yaitu dengan menegur disertai dengan nasehat dan peringatan serta menyita Smartphone milik anak.
Kepemimpinan Ketua Angkatan Muda Masjid Al-Jihad Kelurahan Kertak Baru Ulu Kecamatan Banjarmasin Tengah Kota Banjarmasin
Authors: Yuli Apriati, Reski.P Taufik Hidayat 
Published: September 2021

Penelitian ini bertujuan untuk mengetahui : (1) Gaya Kepemimpinan Ketua Angkatan Muda Masjid Al-Jihad (“AMMA”) Dalam Menjalankan Organisasi; (2) Peran Ketua Angkatan Muda Masjid Al-Jihad (“AMMA”) Dalam Meningkatkan Kinerja Anggotanya.Metode yang digunakan adalah metode penelitian kualitatif. Sumber data yang digunakan data primer dan sekunder, informan dipilih sebanyak enam belas orang secara purposive sampling. Analisis hasil penelitian menggunakan analisis kualitatif..Hasil Penelitian menunjukkan bahwa: (1) Gaya Kepemimpinan Ketua Angkatan Muda Masjid Al-Jihad Dalam Menjalankan Organisasi termasuk dalam Gaya Kepemimpinan Pelatih. (2) Peran Ketua Angkatan Muda Masjid Al-Jihad Dalam Meningkatkan Kinerja Anggotanya, yaitu ketua “AMMA” memberikan apresiasi kepada anggota yang aktif, mengupayakan kondisi kerja yang baik, membangun hubungan interpersonal yang intensif dengan anggota, serta kebijakan organisasi yang akomodatif.Berdasarkan hasil penelitian ini disarankan kepada : (1) Para pengurus dan anggota “AMMA” untuk lebih aktif lagi dan mampu menyeimbangkan kegiatan dan program kerja “AMMA” yang berisifat sosial Masyarakat dan di Masjid Al- Jihad. (2) Diharapkan Pengurus Masjid Al-Jihad terus mendukung semua program kerja AMMA serta mengusahakan adanya fasilitas kantor sekretariat “AMMA”.
Devletlerarası İlişkilerde Kimlik: Mursi Dönemi Türkiye-Mısır İlişkileri
Authors: ÇELİKCAN Harun , CAVLAK Hakan 
Published: September 2021

Türkiye ve Mısır ortak bir tarihsel geçmişe sahip olmalarına rağmen, ilişkileri kuruluşlarından itibaren rekabet ve krizlerin gölgesinde seyretmiştir. Uzun yıllar mesafeli sürdürülen ilişkiler, Arap Baharı sürecinde Mısır’da Muhammed Mursi ile Müslüman Kardeşlerin iktidar olması ile hızla değişmeye başlamış ve ikili ilişkilerin altın çağı olarak kabul edilebilecek bir döneme girilmiştir.
Amaç: Makalenin amacı, Muhammed Mursi İktidarı döneminde Mısır ile Türkiye arasında değişen ilişkileri iki devletin o dönem sahip olduğu kimlikleri üzerinden açıklayarak kimliğin devletlerarası ilişkileri inşa edici rolünü ortaya koymaktır.
Tasarım/Yöntem: Makale tasarımı, sosyal inşacı yaklaşımın varsayımları ışığında ve devlet kimliklerinin dinamik ve değişken bir yapıda olduğu göz önüne alınarak bu dönemde iki devlet kimliğinin ne şekilde değiştiği ve değişen kimlikle beraber ilişkilerin nasıl yeni bir boyut kazandığı soruları üzerine inşa edilmiştir.
Sınırlılıklar: Türkiye-Mısır ilişkilerini incelerken makalenin odağı kimlik olmuştur, ilişkileri etkileyen diğer unsurlara araştırmanın kapsamını sınırlamak ve tasarımına sadık kalmak için bilinçli olarak değinilmemiştir.
Bulgular: Makalede, iki hükümetin birbirlerine yönelik algılarını ve politikalarını anlamak için iki tarafın kimlikleri ve kimliklerinin oluşum süreci incelenmiştir. Söz konusu dönemde Mısır hükümetini oluşturan Müslüman Kardeşler ile Türkiye hükümetini oluşturan Adalet ve Kalkınma Partisi’nin başkanının ve kurucularının önemli bir kısmının etkilendiği Milli Görüş hareketinin fikirsel düzlemde birbirlerine benzedikleri görülmüştür.
Özgünlük/Değer: Türkiye-Mısır ilişkilerinin, Adalet ve Kalkınma Partisi ve Mursi döneminde iyileşmesinde ve siyasi kimliklerinin oluşumunda her iki hükümetin üyelerinin benzer bir ideolojik geçmişten gelmelerinin önemli bir faktör olduğu tespit edilmiştir. Sahip oldukları ortak kimliğin hükümetleri aracılığı ile devletleri etkilediği ve bunun sayesinde de kolaylıkla ortak bir dil geliştirebildikleri ve çıkarlarını ortaklaştırabildikleri iddia edilmiştir. Diğer bir deyişle, ortak veya benzer kimliğe sahip hükümetlerin, devletlerarası ilişkileri geliştirdiği öne sürülmüştür.
Gunshot Fracture of the Femoral Neck: Internal Fixation and Immediate Proximal Femoral Valgus Osteotomy
Authors: Georgiadis Gregory M. , Andrews Kyle A. , Redfern Roberta E. 
Published: September 2021

Case:
We report on a 22-year-old patient with a comminuted femoral neck fracture because of a low-velocity gunshot wound. Treatment consisted of reduction and internal fixation with a fixed angled blade plate and immediate valgus osteotomy. He went on to uneventful healing and an excellent clinical result.

Conclusions:
A comminuted gunshot femoral neck fracture in a young patient is a rare and potentially devastating injury. If stable, and there are no other associated emergent injuries, reduction, internal fixation, and immediate valgus osteotomy should be considered.
Grain size and transport biases in an Ediacaran detrital zircon record
Authors: Cantine Marjorie D. , Setera Jacob B. , Vantongeren Jill A. , Mwinde Chiza , Bergmann Kristin D. 
Published: September 2021

ABSTRACT
Detrital-zircon records of provenance are used to reconstruct paleogeography, sediment sources, and tectonic configuration. Recognition of biases in detrital-zircon records that result from grain-size-dependent processes adds new complexity and caution to the interpretation of these records. We begin by investigating possible size-dependent biases that may affect interpretation of detrital-zircon provenance records in an idealized sedimentary system. Our modeling results show that settling and selective entrainment can differentially affect detrital-zircon spectra if an initial size variation between source zircon populations exists. We then consider a case study: a detrital-zircon record from Ediacaran to Terreneuvian strata of Death Valley, USA, with a focus on the Rainstorm Member of the Johnnie Formation. The detrital-zircon record of the Rainstorm Member shows that despite its unusual, heavy-mineral-rich character, the provenance of the unit is like other units in the succession. Size and density measurements of the grains of the deposit suggest that its enriched heavy-mineral suite is best explained through concentration by selective entrainment and winnowing. The relationship between detrital-zircon grain size and age for samples from the Johnnie Formation are consistent with grain-size influence on the interpretation of provenance, especially for large Grenville-age (1.0–1.2 Ga) zircons. Grain size can exert significant bias on a provenance interpretation and must be accounted for in provenance studies.