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91.
Evolution of an early Eocene pull‐apart basin in the Central Pontides (Northern Turkey): New insights into the origin of the North Anatolian Shear Zone
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Giuseppe Ottria Luca Pandolfi Rita Catanzariti Simone Da Prato Alessandro Ellero Chiara Frassi Mehmet Cemal Göncüoğlu Michele Marroni Leonardo Ruffini Kaan Sayit 《地学学报》2017,29(6):392-400
Although the North Anatolian Shear Zone is one of the main lithospheric‐scale strike‐slip deformation zone in the world, playing a prominent role in the complex geodynamic interaction among the Eurasian, Anatolian and Arabian plates, the onset time of its activity remains highly controversial. Here, we tackle this issue by utilizing nannofossil biostratigraphy on deposits from the Ta?cilar basin, a pull‐apart basin that we have identified inside the North Anatolian Shear Zone overprinting the Intra‐Pontide suture zone. The syn‐tectonic sedimentary succession of the Ta?cilar basin developed completely during the early Eocene (Ypresian; CNE4–CNE5 Zones). The strike‐slip faulting related to the initial onset of the North Anatolian Shear Zone can likely be constrained within the Ypresian, suggesting that the westward escape of the Anatolian plate along the North Anatolian Shear Zone started in the early Eocene. 相似文献
92.
Leonardo E. Bertassello P. Suresh C. Rao James W. Jawitz Antoine F. Aubeneau Gianluca Botter 《水文研究》2020,34(6):1460-1474
Wetlands play an important role in watershed eco-hydrology. The occurrence and distribution of wetlands in a landscape are affected by the surface topography and the hydro-climatic conditions. Here, we propose a minimalist probabilistic approach to describe the dynamic behaviour of wetlandscape attributes, including number of inundated wetlands and the statistical properties of wetland stage, surface area, perimeter, and storage volume. The method relies on two major assumptions: (a) wetland bottom hydrologic resistance is negligible; and (b) groundwater level is parallel to the mean terrain elevation. The approach links the number of inundated wetlands (depressions with water) to the distribution of wetland bottoms and divides, and the position of the shallow water table. We compared the wetlandscape attribute dynamics estimated from the probabilistic approach to those determined from a parsimonious hydrologic model for groundwater-dominated wetlands. We test the reliability of the assumptions of both models using data from six cypress dome wetlands in the Green Swamp Wildlife Management Area, Florida. The results of the hydrologic model for groundwater-dominated wetlands showed that the number of inundated wetlands has a unimodal dependence on the groundwater level, as predicted by the probabilistic approach. The proposed models provide a quantitative basis to understand the physical processes that drive the spatiotemporal hydrologic dynamics in wetlandscapes impacted by shallow groundwater fluctuations. Emergent patterns in wetlandscape hydrologic dynamics are of key importance not only for the conservation of water resources, but also for a wide range of eco-hydrological services provided by connectivity between wetlands and their surrounding uplands. 相似文献
93.
Valquíria Campos Renata Fracácio Leonardo F. Fraceto André H. Rosa 《Aquatic Geochemistry》2012,18(5):433-443
Sterol biomarkers serve as an alternative method for detecting sewage pollution. Sterols were extracted from samples of surface sediment collected in Cubat?o (the Vila dos Pescadores and Vila Esperan?a communities) and quantified using GC–MS after Soxhlet extraction, cleanup, and derivatization. Fecal contamination was evaluated based on the concentration of coprostanol and the ratio of the selected sterols. The most abundant sterol was cholestanol, followed by coprostanol. The concentrations of coprostanol in surface sediments ranged from a minimum of 4.21?μg?g?1 dry sediment (Vila dos Pescadores station) to a maximum of 8.32?μg?g?1 dry sediment (Vila Esperan?a station). A coprostanol concentration of about 10?μg?g?1 was found, indicating areas of high sewage contamination. Coprostanol levels at sewage stations were higher than in other Brazilian coastal areas, which may be attributed to the fraction of the population without sanitation services. 相似文献
94.
Ray L. Frost Yunfei Xi Ricardo Scholz Fernanda M. Belotti Leonardo E. Lagoeiro 《Physics and Chemistry of Minerals》2012,39(10):803-810
Detailed investigation of an intermediate member of the reddingite–phosphoferrite series, using infrared and Raman spectroscopy, scanning electron microcopy and electron microprobe analysis, has been carried out on a homogeneous sample from a lithium-bearing pegmatite named Cigana mine, near Conselheiro Pena, Minas Gerais, Brazil. The determined formula is $ ({\text{Mn}}_{1.60} {\text{Fe}}_{1.21} {\text{Ca}}_{0.01} {\text{Mg}}_{0.01} )_{\sum 2.83} ({\text{PO}}_{4} )_{2.12} \cdot ({\text{H}}_{2} {\text{O}}_{2.85} {\text{F}}_{0.01} )_{\sum 2.86} $ , indicating predominance in the reddingite member. Raman spectroscopy coupled with infrared spectroscopy supports the concept of phosphate, hydrogen phosphate and dihydrogen phosphate units in the structure of reddingite-phosphoferrite. Infrared and Raman bands attributed to water and hydroxyl stretching modes are identified. Vibrational spectroscopy adds useful information to the molecular structure of reddingite–phosphoferrite. 相似文献
95.
Groundwater Modeling of Fractured Aquifers in Mines: The Case Study of Gavorrano (Tuscany,Italy) 总被引:3,自引:1,他引:2
Carlo Alberto Garzonio Leonardo Piccinini Alessandro Gargini 《Rock Mechanics and Rock Engineering》2014,47(3):905-921
In this paper, we describe the hydrogeological problems related to the closure of the mine at Gavorrano (Tuscany, Italy). The geological and geo-structural settings of the Gavorrano area affect the groundwater flow systems and their chemical composition; hence, the settings also affect the chance and modalities to rehabilitate and re-utilize these water resources. This paper reports the results of studies, analyses of existing data and the consequent implementation of preliminary numerical models with particular reference to the effects of controlled water recovery and the complex measures required for stopping dewatering. The study incorporates recent data and the available historical records in an analysis of the hydrodynamic impact of water recovery and an assessment of the consequences of water recovery for water resources restoration. The applied numerical simulations have been demonstrated to be a promising and effective tool for planning and managing the future applications of groundwater recovery in the Gavorrano mining area. Using these applications, it will be possible to implement mitigation measures and types of re-use that consider thermal, chemical and discharge features. 相似文献
96.
Susceptibility analysis of shallow landslides source areas using physically based models 总被引:4,自引:0,他引:4
Rainfall-induced shallow landslides of the flow-type involve different soils, and they often cause huge social and economical
disasters, posing threat to life and livelihood all over the world. Due to the frequent large extension of the rainfall events,
these landslides can be triggered over large areas (up to tens of square kilometres), and their source areas can be analysed
with the aid of distributed, physically based models. Despite the high potential, such models show some limitations related
to the adopted simplifying assumptions, the quantity and quality of required data, as well as the use of a quantitative interpretation
of the results. A relevant example is provided in this paper referring to catastrophic phenomena involving volcaniclastic
soils that frequently occur in southern Italy. Particularly, three physically based models (SHALSTAB, TRIGRS and TRIGRS-unsaturated) are used for the analysis of the source areas of huge rainfall-induced shallow landslides occurred in May 1998 inside an
area of about 60 km2. The application is based on an extensive data set of topographical, geomorphological and hydrogeological features of the
affected area, as well as on both stratigraphical settings and mechanical properties of the involved soils. The results obtained
from the three models are compared by introducing two indexes aimed at quantifying the “success” and the “error” provided
by each model in simulating observed source areas. Advantages and limitations of the adopted models are then discussed for
their use in forecasting the rainfall-induced source areas of shallow landslides over large areas. 相似文献
97.
Roberto Wagner Lourenço Paulo M. Barbosa Landim André Henrique Rosa José Arnaldo F. Roveda Antonio César Germano Martins Leonardo Fernandes Fraceto 《Environmental Earth Sciences》2010,60(3):495-504
Spatial analysis and fuzzy classification techniques were used to estimate the spatial distributions of heavy metals in soil.
The work was applied to soils in a coastal region that is characterized by intense urban occupation and large numbers of different
industries. Concentrations of heavy metals were determined using geostatistical techniques and classes of risk were defined
using fuzzy classification. The resulting prediction mappings identify the locations of high concentrations of Pb, Zn, Ni,
and Cu in topsoils of the study area. The maps show that areas of high pollution of Ni and Cu are located at the northeast,
where there is a predominance of industrial and agricultural activities; Pb and Zn also occur in high concentrations in the
northeast, but the maps also show significant concentrations of Pb and Zn in other areas, mainly in the central and southeastern
parts, where there are urban leisure activities and trade centers. Maps were also prepared showing levels of pollution risk.
These maps show that (1) Cu presents a large pollution risk in the north–northwest, midwest, and southeast sectors, (2) Pb
represents a moderate risk in most areas, (3) Zn generally exhibits low risk, and (4) Ni represents either low risk or no
risk in the studied area. This study shows that combining geostatistics with fuzzy theory can provide results that offer insight
into risk assessment for environmental pollution. 相似文献
98.
Andrews José de Lucena Otto Corrêa Rotunno Filho José Ricardo de Almeida França Leonardo de Faria Peres Luciano Nóbrega Rodrigues Xavier 《Theoretical and Applied Climatology》2013,111(3-4):497-511
This paper aims to map the thermal field in the metropolitan region of Rio de Janeiro (MARJ) considering the atmospheric characteristics and the land use that contribute to understanding the urban heat island. Three thermal maps are defined through the use of Landsat5-TM satellite images for three winter events chosen for the decades of 1980, 1990, and 2000, respectively. The results reveal a concentration of warmer cores in urban central areas as well as some local warmer areas in suburban region. Sites with lower temperatures correspond to vegetated areas which are away from the central part of the MARJ, including points of suburban areas. This work emphasizes the importance of the combined analysis of surface temperature with land use and atmospheric conditions, depicting a distinct pattern of heat islands for tropical climate. 相似文献
99.
100.
Maria Rosaria Santovito Leonardo Tommasi Andrea Romoli Eamonn Murphy 《Planetary and Space Science》2006,54(7):645-660
This paper presents a definition study of a laser altimeter for the topographic exploration of Mercury. The reference scenario is the BepiColombo mission, a cornerstone mission of European Space Agency (ESA) planned for 2012. BepiColombo will offer the chance to make a remarkable new contribution to our knowledge of the Solar System, by venturing into the hot region near the Sun and exploring Mercury, the most enigmatic of the earth's sisters among the terrestrial planets. First images of Mercury surface were acquired by Mariner 10 in 1974 and 1975 offering a coverage and resolution comparable to Earth-based telescopic coverage of the Moon before spaceflight. BepiColombo mission can be very beneficial by using an optical rangefinder for Mercury exploration. In fact starting from the first missions in 1970s until today, laser altimeters have been demonstrating to be particularly appropriate as part of the scientific payload whenever the topography of earth, lunar and planetary surface is the scientific objective of a space mission.Our system design is compliant to Mercury Polar Orbiter (MPO) of the mission. System performance analysis is carried out simulating main hermean topographic features and the potential targets on the planet by means of analytical models and computer codes and several plot are presented to analyse the performance of the instrument. 相似文献