S U M M A R YBased on a critical evaluation of several different spectral magnetic depth determination techniques on areally large synthetic layered and random magnetization models, we recommend the following considerations in the usage of the methods as necessary prerequisites to successful bottom depth determinations: (1) using windows with sufficient width to ascertain that the response of the deepest magnetic layer is captured and by verifying the spectra and computing the depth estimates with the largest possible windows (>300-500 km); (2) avoiding filtering to remove arbitrary regional fields, accomplished by compiling magnetic anomalies derived from modern spherical harmonic degree 13 Earth's main field models [e.g. recent International Geomagnetic Reference Field models (IGRF) or Comprehensive models (CM)]; (3) ascertaining the near-circularity of the autocorrelation function to avoid analysing biased spectra containing strong anomaly trends; and (4) avoid determining the slopes from the exponential, low wavenumber part of the spectra in the cases of layered magnetization. We also describe the details of the new spectral peak forward modelling method and discuss the conditions under which the method can lead to useful results. We found that, despite all these precautions, in some cases, the results can still be erroneous and, therefore, we recommend a critical evaluation of the results by modelling heat flow and taking into account seismic information on the crustal and lithospheric thicknesses and seismic velocities wherever possible. In the southcentral US, east of the Rockies, where the surface heat flow ranges between 40 and 65 mW m −2 , we obtained the magnetic bottom depth of 40 ± 10 km using the approach of the forward modelling of the spectral peak. This range is similar to the seismically derived crustal thickness of 45-50 km, suggesting, therefore, that the entire crust may be magnetic in this region. Because of the uncertainties in the various heat flow contributing parameters, such as the variations in thermal conductivity, radiogenic heat and hydraulic regime, we could not constrain the lithospheric thickness beyond an estimate ranging approximately from 100 to 200 km.

Outsourcing is a management approach by which an organization delegates some noncore functions to specialized and ef®cient service providers. In the era of ªglobal marketº and ªe-economyº, outsourcing is one of the main pillars of the new way to conceive the relationships among companies. Despite outsourcing large diffusion, huge business cases and big deals of documentation available on network or press, there is no structured procedure able to support the govern of the evolution of a generic outsourcing process. In accordance with the principles of total quality management, this paper describes a proposal of a new approach for managing outsourcing processes. The model, which can be easily adapted to different application ®elds, has been conceived with the main aim of managing strategic decisions, economic factors and human resources. The approach is supported by different decision and analysis tools, such as benchmarking techniques, multiple criteria decision aiding (MCDA) methods, cost analysis, and other process-planning methodologies. An application of the method to a real case is also provided.

.[1] It is well known that the Ionian Sea is characterized by thin (8-11 km) crystalline crust, thick (5-7 km) sedimentary cover, and low heat flow, typical for a Mesozoic (at least) basin. Yet seismic data have not yielded univocal interpretations, and a debate has developed on the oceanic versus "thinned continental" nature of the Ionian basin. Here we analyze the magnetic anomaly pattern of the Ionian Sea and compare it to synthetic fields produced by a geopotential field generator, considering realistic crust geometry. The Ionian basin is mostly characterized by slightly negative magnetic residuals and by a prominent positive (150 nT at sea level) "B" anomaly at the northwestern basin margin. We first test continental crust models, considering a homogeneous crystalline crust with K = 1 Â 10 À3, then a 5 km thick deep crustal layer of serpentinite (K = 1 Â 10 À1). The first model yields insignificant anomalies, while the second gives an anomaly pattern anticorrelated with the observed residuals. We subsequently test oceanic crust models, considering a 2 km thick 2A basaltic layer with K = 5 Â 10 À3 , magnetic remanence of 5 A/m, and a unique magnetic polarity (no typical oceanic magnetic anomaly stripes are apparent in the observed data set). Magnetic remanence directions were derived from Pangean-African paleopoles in the 290-190 Ma age window. Only reverse polarity models reproduce the B anomaly, and among them the 220-230 Ma models best approximate magnetic features observed on the abyssal plain and at the western basin boundary. The Ionian Sea turns out to be the oldest preserved oceanic floor known so far.

[1] This paper describes how the joint utilization of autoscaled data such as the F 2 peak critical frequency f o F 2 , the propagation factor M(3000)F 2 , and the electron density profile coming from two reference ionospheric stations (Rome and Gibilmanna), and the regional (Simplified Ionospheric Regional Model Updated) and global (International Reference Ionosphere) ionospheric models can provide a valid tool for obtaining a real-time threedimensional (3-D) electron density mapping of the ionosphere. Preliminary results of the proposed 3-D model are shown by comparing the electron density profiles given by the model with the ones measured at three testing ionospheric stations (Athens, Roquetes, and San Vito).Citation: Pezzopane, M., M. Pietrella, A. Pignatelli, B. Zolesi, and L. R. Cander (2011), Assimilation of autoscaled data and regional and local ionospheric models as input sources for real-time 3-D International Reference Ionosphere modeling, Radio Sci., 46, RS5009,

We present 3‐D magnetic models of Tenerife based on a high‐resolution aeromagnetic survey carried out in 2006. Two different inverse modeling techniques have been applied: (1) a linear method aimed at imaging lateral magnetization contacts and (2) a nonlinear method aimed at obtaining a 3‐D description of deep intrusive bodies, in which a constant magnetization value characterizes the main sources. Magnetic models show that deep intrusive structures are located beneath the northern part of the island and aligned along the E‐W direction. This arrangement of intrusive bodies does not support the hypothesis of a three‐armed rift system that has been present since the early formation of the island. The shallow portion of the intrusive structures shows a round geometry that agrees with the previously proposed location of some of the landslide headwalls, suggesting that collapse scars have acted as preferential sites for magma upwelling. Our magnetic model probably provides the first geophysical evidence of the location of the headwall of the Icod landslide beneath the Teide‐Pico Viejo complex, thus supporting the vertical collapse hypothesis for the origin of the Cañadas caldera. The largest intrusive complex is located to the northwest of Teide and Pico Viejo, revealing the presence of a very high dike density in this area. This complex probably resulted from the intrusion of magma over the span of millions of years, beginning with the early phases of basaltic shield volcanism in central Tenerife and lasting until the building of Teide and Pico Viejo stratovolcanoes.

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We report on the paleomagnetism of ten sites in the products of the most recent silicic eruptive cycle of Pantelleria, Strait of Sicily. Previously radiometrically dated at 5-10 ka, our comparison with proxies for geomagnetic field directions allows us to narrow considerably the time window during which these eruptions occurred. The strongly peralkaline composition causes the magmas to have low viscosities, locally resulting in strong agglutination of proximal fall deposits. This allows successful extraction of paleomagnetic directions from the explosive phases of eruptions. One of our sites was located in the Serra della Fastuca fall deposit, produced by the first explosive event of the eruptive cycle. The other nine sites were located in the most recent explosive (pumice fall and agglutinate from Cuddia del Gallo and Cuddia Randazzo) and effusive (Khaggiar lava) products. The (very similar) paleomagnetic directions gathered from eight internally consistent sites were compared to reference geomagnetic field directions of the last 5-10 ka. Directions from Cuddia del Gallo agglutinate and Khaggiar flows translate into 5.9-to 6.2-ka ages, whereas the Fastuca pumices yield a slightly older age of 6.2-6.8 ka. Hence, the most recent silicic eruptive cycle lasted at most a millennium and as little as a few centuries around 6.0 ka. Paleomagnetically inferred ages are in good agreement with published (and calibrated by us) 14 C dates from paleosols/charcoals sampled below the studied volcanic units, whereas K/Ar data are more scattered and yield ∼30% older ages. Our data show that the time elapsed since the most recent silicic eruptions at Pantelleria is comparable to the quiescence period separating the two latest volcanic cycles.