Initial borehole accelerometer array observations near the north portal of the ESF

This report addresses observed ground motions at the site of the proposed surface facilities associated with the designated repository for high-level nuclear waste at Yucca Mountain, Nevada. In 2003 an accelerometer array was installed at three boreholes on the pad of the north portal of the ESF (Exploratory Studies Facility) at Yucca Mountain, Nevada, by the Nevada Seismological Laboratory (NSL). These boreholes, roughly 150 m apart and initially used for extensive geological and geophysical surveys, were ideal locations to measure the subsurface ground motions at the proposed site of surface facilities such as the Waste Handling Building. Such measurements will impact the design of the facilities. Accelerometer emplacement depths of approximately 15 m from the surface and then at the bottom of the boreholes, roughly 100 m, were chosen. Accelerometers were also placed at the surface next to the boreholes, for a total of nine accelerometers, all three-component. Data recording was accomplished with onsite recorders, with the onsite data transmitted to a central computer at a trailer on the pad. All requirements were met to qualify these data as “Q”. Due to the lack of significant recordings during 2003, several low signal-to-noise (S/N) quality events were chosen for processing. The maximum horizontal peak ground acceleration (PGA) recorded at the pad was approximately 1 cm/s2 in 2003;the corresponding peak ground velocity (PGV) was approximately 0.01 cm/s. PGA and PGV were obtained at all nine accelerometers for most of these events, and spectra were computed. Ground motion amplitudes varied significantly across the boreholes. Higher ground amplifications were observed at the surface for the two boreholes that penetrated a thick amount (~ 30 m) of fill and Quaternary alluvium compared to the one that had less than 2 m of such. Additionally, surface-to-deep recordings showed as much as a factor of five amplification at these two boreholes. Signal correlation with inter-borehole distance agrees with basic Initial Borehole Accelerometer Array Observations Near the North Portal of the ESF Page 6 of 87 scattering theory, and the recorded signals across the wavefront correlate more strongly than those along the propagation path. Transfer functions computed from layered models for each borehole reflect some of the actual signal attributes fairly well, but many more signals need to be recorded and used to provide a good basis of comparison

Southern Great Basin Seismic Network Operations

QAP-3.0 (Scientific Investigation Control) of the University and Community College System of Nevada (UCCSN) Quality Assurance (QA) program requires that, prior to initiating work, a Scientific Investigation Plan (SIP) must be prepared and approved. This SIP is intended to cover the seismic monitoring task performed by the Nevada Seismological Laboratory (NSL). The purpose of this SIP is to describe the high-level planning for the overall task such that it can be referred to by individual scientific notebooks. Due to the continuation nature of this task, this SIP contains language that may be considered generic so that new subtasks can be initiated within an established framework without revision of this SIP. The work described in this SIP, except as noted, is subject to UCCSN QA program requirements

Seismcity in the vicinity of Yucca Mountain, Nevada, for the period October 1, 2000 to September 30, 2001

Starting on October 1, 1995, the monitoring of seismicity within the southern Great Basin near Yucca Mountain was performed with a new digital network. This network features three-component recording with 24-bit A/D conversion in the field. Continuous data are collected at 20 sps, and event triggered windows are collected at 100 sps. A seismic bulletin of events is made by automatically associating triggers among stations, classifying the local earthquake events, and locating the earthquakes and computing their magnitudes with conventional methods. This report covers the operational and seismic results of the sixth full year (FY01) of the improved, digitally based, monitoring. The FY01 earthquake bulletin includes nearly 2000 events within about 65 km of Yucca Mountain. The two largest events in FYO1, both having magnitude (ML) of 3.4, are relatively small compared to the largest events in each of the past 8 years of monitoring by the Nevada Seismological Laboratory. Nearly one-half of the FYO 1 earthquakes are concentrated in the aftershock zone of the 1992 Little Skull Mountain (LSM) earthquake. Hypocentral depths of the aftershocks are largely concentrated in the range of 8-12 km, consistent with previous years. Earthquakes not in the LSM aftershock zone are largely in the 4-12 km range. The observed minimum detection thresholds for earthquakes within the network range in ML from -0.3 to 0.5 or greater, with the lower threshold achieved for earthquakes in the LSM and Yucca Mountain areas where the network is most dense. From the FY01 earthquakes, 37 new short-period first-motion focal mechanisms were reliably determined. These, and the nearly 300 from the previous five years, show a consistent picture of the overall stress field in the region of the digital network. The mean tensional axis is oriented at roughly 60° west of north, at shallow dip, and the pressure axis at roughly 30° east of north, with greater variability in the dip direction accounting for a range of both strike-slip and dip-slip faulting within NW-SE extension. In FY01 three additional small earthquakes occurred within 10 km of the ESF, all with magnitudes \u3c 0.6. A first-motion focal mechanism was determined for one of them — its tensional axis was nearly identical to the mean of the entire set in the last six years. In addition, five small earthquakes were located in the southern part of the Yucca Mountain block, more than 10 km from the ESF. In the Death Valley region, an M 4.3 earthquake occurred in the zone of the Eureka Valley earthquake aftershocks, and five other earthquakes measured M \u3e 3 within the park boundaries. Little of the observed seismicity in the Death Valley region can be related to the two large faults there: Furnace Creek and Death Valley. During FY01 only two local earthquakes provided usable strong-motion recordings. Accelerations were all below l%g for these recordings

Constraints on ground motion at Yucca Mountain provided by precarious rocks

This report describes the methodology and results of the use of precariously balanced rocks to study seismic hazard at Yucca Mountain, Nevada, the site of a potential geologic repository for high-level radioactive waste. Precarious rocks are effectively strong-motion seismoscopes that have been in for place thousands of years. Numerous precarious rocks exist in and near Solitario Canyon, Nevada, immediately above the site of the potential repository. Estimates of toppling accelerations using computer models, physical models, and field tests indicate these rocks would be toppled by ground acceleration of a few tenths of the acceleration of gravity (g). Rock-surface age dating using rock varnish layering and cosmogenic age dating indicate that the rocks have been in place tens of thousands of years. Thus, the precarious rock methodology indicates that Yucca Mountain ground accelerations have not exceeded about 0.3 g for the last several tens of thousands of years. These results are consistent with paleoseismic studies of the Solitario Canyon fault that demonstrate the last significant surface offset capable of producing 0.3 g at the surface took place 75,000 to 80,000 years ago. This report presents recent results of testing, calibration, and application of the precarious rock methodology both at Yucca Mountain and in southern California. In southern California, the seismicity rate is much higher than at Yucca Mountain. Thus, the comparison of results of the precarious rock methodology with Probabilistic Seismic Hazard Analysis (PSHA) results is easier and more accurate. This lends confidence to the application of the methodology to Yucca Mountain. Preliminary results from these precarious rock studies suggest: (1) Probabilistic Seismic Hazard Analysis using current procedures gives values that are too high at low probabilities (e.g.,10 4 annual probabilities). This is true both for Yucca Mountain and for southern California. This is a result of unverified statistical assumptions in PSHA procedures. (2) Current ground-motion estimates for the footwall of major normal faults gives values that are too high. This tends to make the PSHA ground-motion estimates for Yucca Mountain too high. (3) Current ground motion estimates for trans-tensional strike-slip faults are too high. This tends to make the PSHA ground-motion estimates for Yucca Mountain too high. (4) Recent preliminary surface-exposure age dates for the pedestals of precarious rocks at Yucca Mountain are considerably older than some previous estimates. This result tends to confirm the conclusion in (1) above. Although the conclusions of this report have not been formally verified by rigorous peer review, they collectively lend strong support to the conclusion that the ground-motion estimates resulting from the Yucca Mountain Probabilistic Seismic Hazard Analysis (PSHA) are too large, perhaps excessively so

Purification of Chitin from Pupal Exuviae of the Black Soldier Fly

Purpose: Chitin purification from remains (pupal exuviae after metamorphosis to adult flies) of Hermetia illucens farming was optimized performing demineralization, deproteinization and bleaching under different conditions. The optimal parameters to obtain high-purity chitin were determined. Methods: Dried and ground pupal exuviae, whose composition was initially determined, were demineralized using six different acids. Proteins were removed with a NaOH treatment in which temperature, molarity and duration were varied in a randomized experiment. Bleaching was carried out testing ten different chemicals, including NaOCl, H2O2, solvent mixtures and enzymes. The efficiency of each step was determined to assess the optimal conditions for each of them. The resulting chitin was subjected to spectroscopic characterization. Results: The highest demineralization efficiency (90%) was achieved using 0.5 M formic acid for 2 h at 40 °C, confirming the validity of organic acids as a more sustainable alternative to inorganic acids. The treatment with 1.25 M NaOH at 90 °C for 4 h showed the highest deproteinization efficiency, removing 96% of the proteins. Temperature and NaOH concentration were the significant parameters for deproteinization efficiency. The most efficient bleaching treatment was with 6% NaOCl at 60 °C for 1 h (67% efficiency). H2O2 could also be a valid alternative to avoid environmental risk related to chlorine-containing compounds. At the end of the purification process 17% of the original biomass was retained with a chitin content of 85%, corresponding to a chitin yield of 14% related to the initial biomass. Solid-state nuclear magnetic resonance showed that the purified chitin had a degree of acetylation of 96% and X-ray powder diffraction gave a crystallinity index of 74%. Conclusion: This investigation shows an optimized method for extraction of high-purity chitin from H. illucens pupal exuviae, supporting the validity of insect-farming remains as source of this versatile biopolymer. Graphical Abstract: [Figure not available: see fulltext.

Seismicity in the vicinity of Yucca Mountain, Nevada, for the period October 1, 1999 to September 30, 2000

Starting on October 1, 1995, the monitoring of seismicity within the southern Great Basin near Yucca Mountain was performed with a new digital network. This network features three-component recording with 24-bit A/D conversion in the field. Continuous data are collected at 20 sps, and event triggered windows are collected at 100 sps. A seismic bulletin of events is made by automatically associating triggers among stations, classifying the local earthquake events, and locating the earthquakes and computing their magnitudes with conventional methods. This report covers the operational and seismic results of the fifth full year (FYOO) of the improved, digitally based, monitoring. The FYOO earthquake bulletin includes approximately 2300 events within about 50 km of Yucca Mountain. The largest event in FYOO, magnitude (ML) of 3.1, is anomalously low relative to the largest events in each of the 22 prior years of monitoring. Nearly one-half of the FYOO earthquakes are concentrated in the aftershock zone of the 1992 Little Skull Mountain (LSM) earthquake. Another primary contribution to the catalog are aftershocks of the ML 4.7 January 27, 1999, Frenchman Flat earthquake, which continued through FYOO. Hypocentral depths are largely concentrated in the range of 7-12 km, consistent with previous years. This is primarily a consequence of the depth distribution of aftershocks of the LSM earthquake; the LSM rupture surface was confined to between 6 and 12 km. The observed minimum detection thresholds for earthquakes within the network range in ML from -0.3 to 0.5 or greater, with the lower threshold achieved for earthquakes in the LSM and Yucca Mountain areas where the network is most dense. From the FYOO earthquakes, 28 new short-period first motion focal mechanisms were reliably determined. These, and the nearly 260 from the previous four years, show a consistent picture of the overall stress field in the region of the digital network. The tension axis is oriented at roughly 60° west of north, at shallow dip, and the pressure axis at roughly 30° east of north, with greater variability in the dip direction accounting for a collection of both strike-slip and dip-slip faulting within NW-SE extension. In FYOO three additional small events occurred within 10 km of the ESF, all with magnitudes \u3c 0. First-motion focal mechanisms could not be determined for any of these due to the limited number of stations that detected the events. In addition, two events were located in the southern part of the Yucca Mountain block, more than 10 km from the ESF; and a first-motion focal mechanism could be determined for one of these

Properties of Foreshocks and Aftershocks of the Non-Conservative SOC Olami-Feder-Christensen Model: Triggered or Critical Earthquakes?

Following Hergarten and Neugebauer [2002] who discovered aftershock and foreshock sequences in the Olami-Feder-Christensen (OFC) discrete block-spring earthquake model, we investigate to what degree the simple toppling mechanism of this model is sufficient to account for the properties of earthquake clustering in time and space. Our main finding is that synthetic catalogs generated by the OFC model share practically all properties of real seismicity at a qualitative level, with however significant quantitative differences. We find that OFC catalogs can be in large part described by the concept of triggered seismicity but the properties of foreshocks depend on the mainshock magnitude, in qualitative agreement with the critical earthquake model and in disagreement with simple models of triggered seismicity such as the Epidemic Type Aftershock Sequence (ETAS) model [Ogata, 1988]. Many other features of OFC catalogs can be reproduced with the ETAS model with a weaker clustering than real seismicity, i.e. for a very small average number of triggered earthquakes of first generation per mother-earthquake.Comment: revtex, 19 pages, 8 eps figure

Sociodemographic influences on youth sport participation and physical activity among children living within concentrated Hispanic/Latino rural communities

IntroductionLack of physical activity (PA) among children living in rural communities is a documented public health problem. Although studies have examined community conditions defined by a rural–urban dichotomy, few have investigated rural community conditions with a concentration of Hispanic/Latino people. This cross-sectional study examined sociodemographic characteristics associated with youth sport (YS) participation and daily PA among children living within concentrated Hispanic/Latino rural U.S. Midwest communities.MethodsDuring spring 2022, 97% of 3rd–6th grade children (n = 281, aged approximately 8–12 years) attending school in rural Midwestern communities (n = 2) with >50% concentration of Hispanic students participated in the Wellscapes Project, a community randomized trial. Participants completed the Youth Activity Profile and supplemental National Survey of Children’s Health questions assessing PA behaviors and YS participation. Caregivers of a subsample of children (n = 215; males, n = 93; females, n = 122) consented to pair their child’s survey results with school enrollment records (e.g., free/reduced lunch status and race and ethnicity). Mixed models with community as a random effect examined main and interaction effects of grade, sex, ethnoracial status, and family income on YS participation and these sociodemographic characteristics and YS participation on daily moderate-to-vigorous PA (MVPA).ResultsApproximately half of children participated in YS. Non-Hispanic White children (n = 82) were over five times more likely to participate in YS than Hispanic peers (n = 133) (OR = 5.54, 95% CI = 2.64–11.61, p < 0.001). YS participants accumulated 8.3 ± 2.3 more minutes of daily MVPA than non-participants (p < 0.001). Sixth graders, females, and Hispanic children reported lower daily MVPA than comparison groups (p < 0.05). Significant interaction effects on daily MVPA between grade and ethnoracial status (F(3, 204) = 3.04, p = 0.030) were also found.DiscussionDisparities in sport participation and PA outcomes based on sociodemographic characteristics exist among children living in ethnoracially diverse rural communities. Strategies to promote YS participation, including community structural changes, may help reduce PA disparities. The research provides valuable insights for policymakers, public health professionals, and community members to address YS participation barriers, not limited to cost, while considering other PA-promotion efforts to improve child population health

Characterization of low temperature metallic magnetic calorimeters having gold absorbers with implanted 163^{163}Ho ions

For the first time we have investigated the behavior of fully micro-fabricated low temperature metallic magnetic calorimeters (MMCs) after undergoing an ion-implantation process. This experiment had the aim to show the possibility to perform a high precision calorimetric measurement of the energy spectrum following the electron capture of $^{163}$Ho using MMCs having the radioactive $^{163}$Ho ions implanted in the absorber. The implantation of $^{163}$Ho ions was performed at ISOLDE-CERN. The performance of a detector that underwent an ion-implantation process is compared to the one of a detector without implanted ions. The results show that the implantation dose of ions used in this experiment does not compromise the properties of the detector. In addition an optimized detector design for future $^{163}$Ho experiments is presented

THE TOOLS AND MONTE CARLO WORKING GROUP Summary Report from the Les Houches 2009 Workshop on TeV Colliders

This is the summary and introduction to the proceedings contributions for the Les Houches 2009 "Tools and Monte Carlo" working group.Comment: 144 Pages. Workshop site http://wwwlapp.in2p3.fr/conferences/LesHouches/Houches2009/ . Conveners were Butterworth, Maltoni, Moortgat, Richardson, Schumann and Skand