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1.
The identification of syn- and late-orogenic flysch deposits, extending from the Betic Cordillera to the Southern Apennines, assists in the reconstruction of the tectonic-sedimentary evolution of the perimediterranean chains. A microplate was located between the European and African Plates during the Late Jurassic–Early Cretaceous, bordered northwards by the Piemontese Ocean and southwards by another (North Africa ‘Flysch’ Basin or Maghrebian) Ocean. The Piemontese Ocean and the northern margin of the microplate were structured from the Late Cretaceous to the Eocene to create an Eo-alpine Chain. The southern margin of the microplate was deformed in the Aquitanian, when the internal areas of the Maghrebian Ocean were characterized by syn-orogenic flysch deposits. This episode culminated with metamorphism (25–22 Ma) and nappe emplacement, which destroyed the former palaeogeography and created an orogenic belt (AlKaPeCa). Afterwards, a lower Burdigalian late-orogenic cycle started in the deformed area, which as a result of the opening of the Algero-Provençal Basin, caused the fragmentation of the AlKaPeCa, its thrusting on the ‘Flysch’ Basin and the collision with the North Africa and South Iberia Margins. These latter were folded and thrusted, the ‘Flysch’ Units pushed over the External Domain and also back-thrusted. Langhian late-orogenic deposits suture the new tectonic features. Finally, the whole orogen was thrust onto the foredeep during the Middle–Late Miocene. 相似文献
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珀金埃尔默公司分析科学部 《岩矿测试》2008,27(6):483-484
溴是一种在自然水体中都含有的元素,通常以B r-的形式存在。目前最常用的水净化方式就是向水中通入臭氧以杀灭细菌;而臭氧分解的副产物即为B r-转换成的B rO3-,这是一种公认的致癌物质。本实验室曾使用阴离子交换高效液相色谱(HPLC)与等离子体质谱(ICP-MS)联用分析B rO3-和B r-,方法虽能有效地将这两种溴形态分离,但分析每个样品需8 m in。本文试图建立新的方法缩短分析时间,并验证该方法应用于实际水样分析时测定其他含溴化合物的能力。1实验部分1.1高效液相色谱分析条件表1列出了等度淋洗和梯度淋洗两种模式下HPLC的分析条件,完成形态的分离。等度淋洗和梯度淋洗在分析中显示出不同 相似文献
3.
G. Colangelo V. Lapenna A. Perrone S. Piscitelli L. Telesca 《Engineering Geology》2006,88(3-4):274-286
A geoelectrical monitoring activity has been carried out to improve the geological and hydrogeological knowledge about the Varco d'Izzo landslide (Potenza, Basilicata, Southern Apennine, Italy), an active rotational–translational slide evolved in earth-flow. In this work we have focused on the Self-Potential (SP) method by applying three different SP measuring techniques and combining modern technologies for data acquisition and new methods for tomographic inversion. A SP map and three static SP tomographies have been carried out to better analyse the groundwater circulation system and to better reconstruct the geometry of the landslide body. In the accumulation zone, which is the area more exposed to the geomorphological activity, a new SP measuring strategy has been applied. This strategy, based on time-continuous 2D SP tomographies, helps identify water flow changes in subsurface by studying the time series of SP tomographic images. The analysis of time-dependent changes of water infiltration in near surface is the key to better understand the hydrogeological processes underlying the ground instability phenomena. The time-lapse analysis of tomographic images has allowed us not only to investigate the correlation between the temporal changes of SP signals and rainfall events, but also to quantify the range of these changes. The modification of the distribution of the SP source accumulation zones is associated with the dynamics of the groundwater flows. These preliminary results allow us to consider the SP tomographic method as a tool for geophysical monitoring of landslide areas and encourage to develop new measuring systems for near-real time applications. 相似文献
4.
Martín-Algarra A Messina A Perrone V Russo S Maate A Martín-Martín M 《The Journal of geology》2000,108(4):447-467
The Malaguide-Ghomaride Complex is capped by Upper Oligocene-Aquitanian clastic deposits postdating early Alpine orogenesis but predating the main tectonic-metamorphic evolution, end of nappe emplacement, unroofing, and exhumation of the metamorphic units of the Betic-Rif Orogen. Two conglomerate intervals within these deposits are characterized by clasts of sedimentary, epimetamorphic, and mafic volcanic rocks derived from Malaguide-Ghomaride units and by clasts of acidic magmatic and orthogneissic rocks of unknown provenance, here studied. Magmatic rocks originated from late-Variscan two-mica cordierite-bearing granitoids and, subordinately, from aplitic dikes. Orthogneisses derive from similar plutonic rocks but are affected by an Alpine metamorphic overprint evolving from greenschist (T=510&j0;-530 degrees C and P=5-6 kbar) to low-temperature amphibolite facies (T>550&j0;C and P<3 kbar). Such a plutonic rock suite is unknown in any Betic-Rif unit or in the basement of the Alboran Sea, and the metamorphic evolution in the orthogneisses is different from (and older than) that of Alpujarride-Sebtide rocks to which they were formerly ascribed. Magmatic and metamorphic rocks very similar to those studied characterize the basements of some Kabylia and Calabria-Peloritani units. Therefore, the source area is a currently lost continental-crust realm of Calabria-Peloritani-Kabylia type, located to the ESE of the Malaguide-Ghomaride Domain and affected by a pre-latest Oligocene Alpine metamorphism. Increasingly active tectonics transformed this realm into rising areas from which erosion fed small subsiding synorogenic basins formed on the Malaguide-Ghomaride Complex. This provenance analysis demonstrates that all these domains constituted a single continental-crust block until Aquitanian-Burdigalian times, before its dispersal around nascent western Mediterranean basins. 相似文献
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6.
Local Groundwater Withdrawal Permitting Laws in the South‐Western U.S.: California in Comparative Context 
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下载免费PDF全文 The Sustainable Groundwater Management Act (SGMA) aims to control, for the first time in California's history, the state's significant use and depletion of groundwater. SGMA gives local agencies a high degree of discretion in relation to a new permitting power, but the discretion is a double‐edged sword: agencies gain maximum flexibility to tailor their regime to local conditions, yet the statute provides no direction on appropriate components of a groundwater permitting regime. We introduce SGMA and the broader legislative context to its permitting power, and we explain the continuing common law context in which the legislation operates. This information is used as the foundation for a comparative legal analysis of fundamental elements of permitting regimes. We compare a selection of six other south‐western permitting regimes established in legislation for areas recognized as requiring intensive management through permitting: “special permitting areas” (SPAs). We find that permitting regimes in south‐western SPAs share a structure containing several almost universal elements, although the policy settings that apply to those elements vary widely. The established permitting regimes in the other south‐western states' SPAs may inform Californian agencies seeking to use their new permitting power for the first time, as well as water agencies further afield, as to important components of a permitting regime, and the different policy settings that could apply to those components. Californian local agencies, and its Department of Water Resources, which is charged with providing local agencies technical advice, should have regard to these permitting possibilities. 相似文献
7.
A performance-based adaptive methodology for the seismic evaluation of multi-span simply supported deck bridges 总被引：1，自引：1，他引：0
Donatello Cardone Giuseppe Perrone Salvatore Sofia 《Bulletin of Earthquake Engineering》2011,9(5):1463-1498
A performance-based adaptive methodology for the seismic assessment of highway bridges is proposed. The proposed methodology
is based on an Inverse (I), Adaptive (A) application of the Capacity Spectrum Method (CSM), with the capacity curve of the
bridge derived through a Displacement-based Adaptive Pushover (DAP) analysis. For this reason, the acronym IACSM is used to
identify the proposed methodology. A number of Performance Levels (PLs), for which the seismic vulnerability and seismic risk
of the bridge shall be evaluated, are identified. Each PL is associated to a number of Damage States (DSs) of the critical
members of the bridge (piers, abutments, joints and bearing devices). The IACSM provides the earthquake intensity level (PGA)
corresponding to the attainment of the selected DSs, using over-damped elastic response spectra as demand curves. The seismic
vulnerability of the bridge is described by means of fragility curves, derived based on the PGA values associated to each
DS. The seismic risk of the bridge is evaluated as convolution integral of the product between the fragility curves and the
seismic hazard curve of the bridge site. In this paper, the key aspects and basic assumptions of the proposed methodology
are presented first. The IACSM is then applied to nine existing simply supported deck bridges, characterized by different
types of piers and bearing devices. Finally, the IACSM predictions are compared with the results of nonlinear response time-history
analysis, carried out using a set of seven ground motions scaled to the expected PGA values. 相似文献
8.
Spinner dolphins Stenella longirostris longirostris off the south-west coast of Mauritius are subject to ongoing anthropogenic disturbance in the form of daily dolphin tourism, which has intensified since 1998. Abundance of this species was estimated using photo-identification data and mark-recapture analysis. Between April 2008 and June 2010, identification photographs were collected from dolphins occurring along a 30 km length of the coast of south-west Mauritius. A total of 250 groups were encountered over 229 survey days. Mark-recapture analyses were performed on a photographic dataset of more than 8 000 good- and excellent-quality images and 83 animals were identified as distinctively marked individuals. The majority (85.5%) were seen more than once and resightings indicated a resident population. The compiled version of SOCPROG 2.4 was used to investigate the lagged identification rate. The fitted model supported a mostly resident population with additional animals moving in and out of the study area. The estimated abundance of the total population in the study area ranged between 138 and 399 individuals. Our results can be used for monitoring the population for fluctuations and for encouraging both the enforcement of laws regarding dolphin watching and the development of further means of management needed to ensure the long-term presence of this population. 相似文献
9.
G. Pavese F. De Tomasi M. Calvello F. Esposito M.R. Perrone 《Atmospheric Research》2009,92(4):489-504
Measurements from July 4 to July 8, 2005 by a high resolution visible radiometer, a Raman lidar, a ground particulate matter sampler, and ground meteorological sensors have been combined in synergy to infer the intrusion over south-east Italy, of air masses from north-west Sahara, the Atlantic Ocean, and the continental Europe. It is shown that backscatter coefficient, depolarization-ratio, and lidar ratio vertical profiles represent the best tools to detect the intrusion of long range transported air masses and to monitor their effects on the vertical distribution of aerosol optical and microphysical properties. High resolution radiometers are instead important tools to monitor changes on columnar aerosol properties and size distributions.Backscatter coefficient, depolarization-ratio, and lidar ratio vertical profiles have revealed that aerosol optical and microphysical properties significantly changed with time and space during African dust outbreaks: the intrusion of dust particles that at first occurred above 2 km of altitude extending up to 6 km, affected the all aerosol load down to ground within few hours. Aerosol size distributions showed during dust events a clear bimodality with an accumulation mode maximum at 0.24 µm and a coarse mode maximum at 0.94 μm. Conversely, we have found that during the advection of air masses from the Atlantic and continental Europe, aerosol particles were mainly located below 2 km, their optical and microphysical properties were affected by smaller changes in time and space, and were characterized by depolarization ratios rather close to those due to a pure molecular atmosphere. In this case bimodal size distributions with an accumulation mode showing two sub-modes at 0.16 μm and 0.24 μm, respectively and a coarse mode centred at 0.94 μm have also been observed. 相似文献
10.
In this paper temperature enhanced -decay at high stellar temperatures is investigated in conjunction withs-process nucleosynthesis. The temperature dependence of -decay is the result of more energetic, hence faster, decay from thermally excited nuclear states. A formula for the effective halflife is derived as a function of the atomic number and weight, temperature, and the -decayQ-value of the isotope. The effect of such enhanced -decay upons-process abundances is discussed, and information abouts-process neutron flux intensities is deduced based on the calculated -decay halflives of the isotopes Nd 144 and Sm 150. The neutron flux-temperature relationships are compared to specific constant temperature carbon-burning models of massive stars which are considered to be possible sources of solar systems-process abundances. Finally, information regarding the time betweens-process termination and final interstellar injection ofs-process material is derived using the decay calculations. 相似文献