The crustal structure of the southern Rhinegraben from re-interpretation of seismic refraction data

The Rhinegraben is one of the best studied rift structures in the world. In the past 20 years, it has been the site of many seismic refraction studies. However, most of the profiles have only been interpreted using 1-D methods. In this paper a combined 2-D and 1-D analysis of the only reversed profile within the graben proper is presented. The new interpretation has resulted in changes in the P-wave velocity model of the Rhinegraben. In the new model, the upper crust of the graben, representing the sedimentary graben-fill, is found to be 6-7 km thick with Vp less than 6.0 km/s. The mid-crust, which is probably of granitic/gneissic composition, shows a practically constant velocity of 6.25 km/s. This observation is supported by seismic reflection data. At the base of the crust is a velocity discontinuity followed by a 1.5 km thick transition zone into the upper mantle. From north to south along the graben, the crust thins by 3 km and the upper mantle velocity changes from about 8.4 km/s to 7.9 km/s. In comparison with the old 1-D model, the new model shows a simplification of the structure of the lower crust and a thinning of the crust/mantle transition zone from 5 km to 1.5 km. Furthermore, in the old model, the upper mantle velocity underneath the graben was found to be constant at 8.1 km/s, which is in contrast to the changing upper mantle velocity found in the new model.           ARK: https://n2t.net/ark:/88439/y019805 Permalink: https://geophysicsjournal.com/article/241 &nbsp

Seismic imaging for velocity and attenuation structure in geothermal fields

We have applied the attenuation inversion technique developed by Evans and Zucca (1988) to a seismic tomographic data set taken at Newberry Volcano by Achauer et al. (1988). Our preliminary results suggest that the interpretation of the velocity data by Achauer et al. that a magma chamber is present 3 km beneath the caldera is not confirmed by the attenuation data

Wide-angle seismic constraints on the internal structure of Tenerife, Canary Islands

We have used wide-angle seismic data to constrain the internal structure of Tenerife, Canary Islands. The experiment was designed as a seismic fan profile to detect azimuthal variations in the seismic structure of the volcanic edifice and its flanks. Seismic energy was generated using a 75-1 airgun-array on board the RRS Charles Darwin fired every 40 s along a quasi-circular profile around the island of Tenerife, centered on Teide volcano. We present the results obtained from the data recorded by five portable land stations distributed on the island. The travel-times indicate that the averaged P-wave velocity within the volcanic edifice is greater than 6 km/s. The observed travel-times were reduced to residual travel-times by removing the effects of variations in the bathymetry along the profile, variations in the shot-receiver distance, and from local heterogeneities. Negative residual travel-times up to 0.8 s in amplitude indicate that the southwestern part of Tenerife is characterized by a high P-wave velocity zone, coincident with a gravity maximum that was previously modeled as a high-density body forming the core of an old, large mafic volcano. We estimate velocities greater than 7.3 km/s within the anomalous body, suggesting that it represents an intrusive plutonic complex. This high-velocity, high-density body may have played an important role in the evolution of Tenerife, buttressing Las Cañadas edifice and preventing the occurrence of landslides in the southern and western areas of Tenerife. The bathymetric high between Tenerife and La Gomera is associated with travel-time delays up to 0.4 s, suggesting that it may be composed of large deposits of lava flows and volcaniclastic materials, probably erupted from the shield massifs of Teno, Roque del Conde, and La Gomera. The post-shield volcanic zones of Santiago and Dorsal rifts also seem to be characterized by moderate high P-wave velocities. © 2000 Elsevier Science B. V. All rights reserved

Genome-wide association study identifies multiple susceptibility loci for diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common lymphoma subtype and is clinically aggressive. To identify genetic susceptibility loci for DLBCL, we conducted a meta-analysis of 3 new genome-wide association studies (GWAS) and 1 previous scan, totaling 3,857 cases and 7,666 controls of European ancestry, with additional genotyping of 9 promising SNPs in 1,359 cases and 4,557 controls. In our multi-stage analysis, five independent SNPs in four loci achieved genome-wide significance marked by rs116446171 at 6p25.3 (EXOC2; P = 2.33 7 10 '21), rs2523607 at 6p21.33 (HLA-B; P = 2.40 7 10 '10), rs79480871 at 2p23.3 (NCOA1; P = 4.23 7 10 '8) and two independent SNPs, rs13255292 and rs4733601, at 8q24.21 (PVT1; P = 9.98 7 10 '13 and 3.63 7 10 '11, respectively). These data provide substantial new evidence for genetic susceptibility to this B cell malignancy and point to pathways involved in immune recognition and immune function in the pathogenesis of DLBCL. \ua9 2014 Nature America, Inc. All rights reserved

Euclid preparation: V. Predicted yield of redshift 7 < z < 9 quasars from the wide survey

We provide predictions of the yield of 7 &lt; z &lt; 9 quasars from the Euclid wide survey, updating the calculation presented in the Euclid Red Book in several ways. We account for revisions to the Euclid near-infrared filter wavelengths; we adopt steeper rates of decline of the quasar luminosity function (QLF; \u3c6) with redshift, \u3c6\ue2 10k(z - 6), k = -0.72, and a further steeper rate of decline, k = -0.92; we use better models of the contaminating populations (MLT dwarfs and compact early-type galaxies); and we make use of an improved Bayesian selection method, compared to the colour cuts used for the Red Book calculation, allowing the identification of fainter quasars, down to JAB 3c 23. Quasars at z &gt; 8 may be selected from Euclid OYJH photometry alone, but selection over the redshift interval 7 &lt; z &lt; 8 is greatly improved by the addition of z-band data from, e.g., Pan-STARRS and LSST. We calculate predicted quasar yields for the assumed values of the rate of decline of the QLF beyond z = 6. If the decline of the QLF accelerates beyond z = 6, with k = -0.92, Euclid should nevertheless find over 100 quasars with 7.0 &lt; z &lt; 7.5, and 3c25 quasars beyond the current record of z = 7.5, including 3c8 beyond z = 8.0. The first Euclid quasars at z &gt; 7.5 should be found in the DR1 data release, expected in 2024. It will be possible to determine the bright-end slope of the QLF, 7 &lt; z &lt; 8, M1450 &lt; -25, using 8 m class telescopes to confirm candidates, but follow-up with JWST or E-ELT will be required to measure the faint-end slope. Contamination of the candidate lists is predicted to be modest even at JAB 3c 23. The precision with which k can be determined over 7 &lt; z &lt; 8 depends on the value of k, but assuming k = -0.72 it can be measured to a 1\u3c3 uncertainty of 0.07