The convergence of innovation in satellite communications, 5G terrestrial systems and cloud technology promises a ubiquitous networking solution, which offers a wide range of features, including but not limited to: universal multiaccess coverage at extraordinarily high speeds & capacity, multi-tenancy, fixed and wireless access network convergence, software controlled, agile service provisioning, on-demand service-oriented resource allocation, and highly orchestrated. To meet the needs of future communication, a paradigm shift both in the terrestrial and satellite segments is needed, transforming them from data-only transport media to intelligent services, equipped with computational, storage and decision-making capacities. In this article, we present H2020 SaT5G project vision to integrate the next generation satellite systems into 5G terrestrial networks at different levels. To this end, after highlighting the benefits of the integrated satellite-5G systems via some potential use cases, we detail the architectural options proposed by the project. In addition, we will present a management solution for the effective management and orchestration of the end-to-end heterogeneous technologies (terrestrial and satellite services).

The 176Hf/177Hf ratio of seawater is measured directly with 143Nd/144Nd in a composite vertical profile in the NE Atlantic. The value of ɛHf of intermediate and deep water exhibits little variation and averages +1.0 ± 0.8; surface water shows a wider range, −5.7 to +3.3. While intermediate and deep water samples plot on, or close to, the seawater Hf‐Nd isotope array, defined by ferromanganese deposits, near‐surface seawater samples plot between the seawater and terrestrial rock ɛHf − ɛNd arrays. It is likely that the shallow water variability in ɛHf arises from a short residence time of Hf in surface water and isotopically heterogeneous inputs. The difference between surface and intermediate‐deep water ɛHf may be maintained by the release of surface scavenged Hf at depth from a subset of sinking particles; the composition of εNd at middepths reflects overlying surface water and water advected along isopycnals from areas where they outcrop in winter. Uniform ɛHf values below 1000 m suggest the residence time of Hf may be longer than that of Nd. The radiogenic isotopic composition of seawater Hf relative to Nd and terrestrial rocks suggests that minerals with high Lu/Hf ratios may be preferentially weathered, providing a source of radiogenic Hf to the oceans.

The Catalina Schist underlies the inner southern California borderland of southwestern North America. On Santa Catalina Island, amphibolite facies rocks that recrystallized and partially melted at ca. 115 Ma and at 40 km depth occur atop an inverted metamorphic stack that juxtaposes progressively lower grade, high-pressure/ temperature (PT) rocks across low-angle faults. This inverted metamorphic sequence *marty@oro.ess.ucla.edu Grove, M., Bebout, G.E., Jacobson, C.E., Barth, A.P., Kimbrough, D.L., King, R.L., Zou, H., Lovera, O.M., Mahoney, B.J., and Gehrels, G.E., 2008, The Catalina Schist: Evidence for middle Cretaceous subduction erosion of southwestern North America, in Draut, A.E., Clift, P.D., and Scholl, D.W., eds., Formation and Applications of the Sedimentary Record in Arc Collision Zones: Geological Society of America Special Paper 436, p. 335–361, doi: 10.1130/2008.2436(15). For permission to copy, contact editing@geosociety.org. ©2008 The Geological Society of America. All rights reserved.

Ultra-high-pressure eclogites from the Dabie orogen that formed over a range in temperatures (similar to 600 to > 700 degrees C) have been investigated with combined Lu-Hf and Sm-Nd geochronology. Three eclogites, sampled from Zhujiachong, Huangzhen and Shima, yield Lu-Hf ages of 240.0 +/- 5.0, 224.4 +/- 1.9 and 230.8 +/- 5.0 Ma and corresponding Sm-Nd ages of 222.5 +/- 5.0, 217.6 +/- 6.1 and 224.2 +/- 2.1 Ma respectively. Well-preserved prograde major- and trace-element zoning in garnet in the Zhujiachong eclogite suggests that the Lu-Hf age mostly reflects an early phase of garnet growth that continued over a time interval of c. 17.5 Myr. For the Huangzhen eclogite, despite preserved elemental growth zoning in garnet, textural study reveals that the Lu-Hf age is biased towards a later garnet growth episode rather than representing early growth. The narrow time interval of < 6.6 Myr defined by the difference between Lu-Hf and Sm-Nd ages indicates a short final garnet growth episode and suggests a rapid cooling stage. By contrast, the rather flat element zoning in garnet in the Shima eclogite suggests that Lu-Hf and Sm-Nd ages for this sample have been reset by diffusion and are cooling ages. The new Lu-Hf ages point to an initiation of prograde metamorphism prior to c. 240 Ma for the Dabie orogen, while the exact peak metamorphic timing experienced by specific samples ranges between c. 230 to c. 220 Ma.

We demonstrate an approach to examining the metamorphic history of subducting oceanic crust that can complement records of subduction zone chemical cycling derived from studies of igneous rocks produced at volcanic arcs. By merging methods utilizing garnet zoning to establish prograde reaction histories with in situ high‐resolution trace element geochemistry, and application to coesite‐bearing mafic eclogites representing subduction to depths beneath arcs, we are able to directly identify geochemical manifestations of reactions contributing to element mobility in the subducting slab that are only inferred in studies of volcanic arcs or theoretical metamorphic models. Specifically, we identify a prograde metamorphic reaction, based solely on the zoning of geochemistry and mineral inclusions within garnet, and infer that these features are a record of the breakdown of coexisting clinozoisite + titanite and probable liberation of trace element–laden fluid from the rock during prograde metamorphism. We are then able to assign a specific depth interval for the reaction through calculation of the P‐T dependence of the reaction for these eclogites and comparison with a published P‐T trajectory. Because of the robust preservation of records of petrologic and geochemical processes by garnet, this methodology is particularly suited for study of ultrahigh‐pressure (UHP) eclogites, in which severe retrograde alteration (generally related to exhumation) commonly obscures prograde history.

Ultramafic blocks within mud-matrix melange of the Franciscan Complex, California, preserve a series of metasomatic mineral zones generated by infiltration of Si-rich hydrous fluids during subduction. We describe the petrology and geochemistry of the metasomatic zones and compare them to current model predictions for the metasomatism of the mantle wedge by subduction zone fluids. Fluid flow affected a Cr-spinel lherzolite protolith to form first serpentinite, then a talc-dominated rock, and finally an amphibole-rich assemblage. A diverse suite of accessory minerals in the amphibole-rich zone (titanite + clinozoisite + zircon + apatite) suggests that the trace element signature of subduction zone fluids may be fractionated in this zone. Oxygen isotopic evidence suggests that the ultramafic blocks equilibrated with metasomatic fluids during serpentinization and that subsequent reactions occurred in equilibrium with these fluids in a temperature range of 450-500 degreesC. Whole-rock geochemistry indicates mobility of many elements into and out of the blocks during metasomatism, including elements such as Ti which are currently considered to have low solubilities in such fluids.Taken as a whole, the blocks appear to preserve the metasomatic structure of the slab-mantle interface in subduction zones and imply that the chemistry of slab-derived fluids is modified as they pass through these metasomatic zones in the mantle wedge. Our results suggest that the primary composition of subduction zone fluids is not likely reflected by arc magmas. Instead, we propose that arc magmas are derived from regions of the mantle fluxed by fluids residual to the metasomatic processes we observe.

Models for the geochemistry of arc volcanic rocks and geochemical cycling through subduction zones are substantially hampered by the unknown variables that affect subducted lithologies deep within subduction zones. While inferences regarding apparent element mobility or retention during slab metamorphism have been made from indirect sources (i.e., arc volcanic suites), comparatively little direct evidence exists regarding the geochemical evolution of melange. To address the dual effects of mechanical and metasomatic mixing in the production of melange geochemistry, we are developing trace element and Li-B-SrNd-Pb isotopic data for melange matrix at a variety of metamorphic grades from a well-characterized subduction complex, the Catalina Schist, CA, USA. Field relations, petrology, and major-element geochemisty for amphibolite-facies melange matrix from the Catalina Schist indicate mixing of mafic and ultramafic components, with negligible evidence for mechanical incorporation of sediments (Bebout and Barton, 2002). We model trace element contributions using a binary mixing model assuming Yb and Lu are fluid-immobile reference frame elements. “Residual” compositions for other trace elements predicted by the mixing model then ideally reflect the enrichment or depletion of trace elements in the melange by fluid flow. Residual compositions indicate overall depletion for Cs, Rb, B, Zr, and Hf, yet enrichment for Ba, Sr, Li, U, Th, Pb, Nb, and Ta, suggesting decoupling of traditional geochemical groups within melange zones. Positive REE residuals smoothly decrease in normalized concentration from LREE to HREE, consistent with higher LREE partitioning in fluids. While NMORB-normalized trace element concentrations range from <0.01 to ~1, [La/Yb]N, Th/Yb, and Nb/Ta ratios for the melange matrix (as well as metasomatic rinds on mafic blocks in melange; Sorensen and Grossman, 1989) appear to reflect the influence of a fluid derived from or equilibrated with sediments, in agreement with existing δO and δD data (Bebout, 1991).

This paper reports on the effectiveness of employing Duffing type nonlinear stiffness in limiting rotor blade lead/lag motion and reducing susceptibility to ground resonance. Classic instability on isotropic supports is stabilized in limit cycle response at amplitudes sufficiently low to avoid destructive ground resonance without the use of auxiliary lag dampers. A Duffing spring stiffness is defined as a function of the cube of the spring displacement: F = K(d)x(3) as compared to the linear spring relation F = Kx. This nonlinearity in the Duffing equation leads to a shift in the resonant frequency as a function of the displacement. A three bladed articulated rotor model is employed similar to that used by Coleman in his classic work on ground resonance.

Zircon and baddeleyite occur within quartz–tourmaline veins at four gold deposits in the Val-d'Or district of the Archean Abitibi Southern Volcanic Zone. Host rocks have experienced intense metasomatic enrichment of Zr, Hf, Y, and rare earth elements. The zircons contain primary inclusions of quartz, tourmaline, pyrite, albite, K-mica, scheelite, and gold, and gold occurs in primary fluid inclusions in zircons. Magmatic zircons in host rocks do not have this suite of inclusions; consequently a wall-rock inheritance model for the vein zircons is implausible. Compositionally, the zircons feature pronounced interzone and intergrain variations of Hf, Y, Yb, Th, and U, and sporadic anomalous Ce contents of ~ 1100 ppm, distinct from magmatic counterparts. Two principal types of primary fluid inclusion occur in the vein zircons. Type 1 H2O–CO2 inclusions have low salinities, variable quantities of CO2 and homogenization temperatures of 260–380 °C, and type 2 CO2 rich inclusions contain minor H2O and CH4. The vein zircons coprecipitated at 260–380 °C and ~ 2 kbar (1 kbar = 100 MPa) with coexisting minerals of undisputed hydrothermal origin, such as vein quartz and gold. In the Superior Province, mesothermal gold deposits are related in space and time to translithospheric structures that mark the diachronous accretion of allochthonous subprovinces from north to south between ~ 2710 and 2680 Ma. Consequently, vein zircon ages of ~ 2680 Ma record the primary mineralizing event, whereas aberrantly young ages for rutile, titanite, scheelite, and micas in the same vein systems, that scatter over 2630–2579 Ma, reveal the age of secondary remobilization events.