Source apportionment and health risk assessment of heavy metals in soil for a township in Jiangsu Province, China

Water is a key ingredient in the generation of magmas in subduction zones. This review focuses on the role of water in the generation of magmas in the mantle wedge, the factors that allow melting to occur, and the plate tectonic variables controlling the location of arc volcanoes worldwide. Water also influences chemical differentiation that occurs when magmas cool and crystallize in Earth’s continental crust. The source of H2O for arc magma generation is hydrous minerals that are carried into Earth by the subducting slab. These minerals dehydrate, releasing their bound H2O into overlying hotter, shallower mantle where melting begins and continues as buoyant hydrous magmas ascend and encounter increasingly hotter surroundings. This process is controlled by plate tectonic variables that ultimately influence the location of the active volcanic arc above subduction zones. Water also modifies the thermodynamic properties of melts, leading to the unique chemical composition of arc volcanic rocks and Earth’s continental crust.

The Role of H 2 O in Subduction Zone Magmatism

The Polycyclic Aromatic Hydrocarbons (PAHs or polyaromatic hydrocarbons) have been extensively studied to understand their distribution, fate and effects in the environment (Haftka 2009; Laane et al. 1999, 2006, 2013; Okuda et al. 2002; Page et al. 1999; Pavlova and Ivanova 2003; Stout et al. 2001a; Zhang et al. 2005). They are organic compounds consisting of conjoined aromatic rings without heteroatoms (Schwarzenbach et al. 2003). Sander and Wise (1997) list 660 parent PAH compounds (i.e., aromatic substances without alkyl groups and consisting solely of fused rings connected to each other), ranging from the monocyclic molecule of benzene (molecular weight = 78) up to nine-ringed structures (MW up to 478). PAHs containing one or more alkyl groups are called alkyl PAHs. Our study deals with the parent compounds (without alkyl groups and/or heteroatoms), the alkyl PAHs (denoted as PAHn, with n referring to the number of methyl groups; see footnotes in Table 1), and certain heterocyclic sulfur PAHs (dibenzothiophenes). The term PAHs includes all the above, unless explicitly specified. In Table 1, we present the nomenclature of PAHs used in this paper.

https://www.springer.com/cda/content/document/cda_downloaddocument/9783319106373-c1.pdf?SGWID=0-0-45-1486896-p176905844

Source characterization of polycyclic aromatic hydrocarbons by using their molecular indices: an overview of possibilities

From rifting to drifting: tectonic evolution of the South-Alpine upper crust from the Triassic to the Early Cretaceous

Spatial distribution and source apportionment of heavy metals in soil from a typical county-level city of Guangdong Province, China.

Characterization of the Danube River sediments using the PMF multivariate approach

In this work, we investigated a 3 ha sulphide-bearing waste-rock dump (Libiola Mine, Italy) using mineralogical, geochemical, and geostatistical analyses. The dumped materials were highly heterogeneous in grain size and lithology and varied both laterally and vertically. Other than the host rock of the ore, basalts and serpentinites, the dumped materials contained high amounts of low-grade chalcopyrite- and pyrite-rich mineralisations. Due to these characteristics and to the absence of minerals able to neutralise acidity, this waste-rock dump can be classified as an acid mine drainage (AMD) producer. The study confirms that AMD is still active and, in the best scenario, can persist for up to 6.17 × 103 years. The consequences of this process are of serious environmental concern as it involves strong acidification of the circulating waters, the release of potentially toxic metals into the soil, streams and rivers and the precipitation of huge quantities of secondary Fe-oxides and Fe-oxyhydroxides.

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Mineralogical and geochemical spatial analyses of a waste-rock dump at the Libiola Fe–Cu sulphide mine (Eastern Liguria, Italy)

New K-Ar age determinations on the gneisses and schists of the south-Alpine basement of the Orobic Alps and their separated minerals have been carried out to supplement and support the previous study ofBocchio et al. (1981). The cooling ages of biotites and muscovites range from 218 to 331 my and from 170 to 330 my respectively, according to a bimodal distribution with modes at 222 and 298 my for biotite, 182 and 322 my for muscovite. The whole rock ages spread from 43 to 402 my with no significant cluster. Only a few samples give statistically significant internal isochrones, and these suggest two periods of equilibration, at 226–245 and 312–368 my. These age determinations support the conclusion drawn from regional petrologic studies (Bocchio et al., 1980;Crespi et al., 1980), that the south-Alpine basement underwent two main phases of metamorphism, now preferentially preserved in different areas: an old, Hercynian phase under a regime of intermediate pressure (staur-ky type), and a young, post-Hercynian phase under a regime of low pressure (staur-sill type) reactivated by the cover of the thick sedimentary pile on top of the basement. Furthermore, radiometric ages also point out the widespread but irregularly distributed occurence of an alpine overprint under the conditions of a very low metamorphic regime, that is documented by the growth of post-kinematic stilpnomelane in rocks of suitable bulk composition (Crespi et al., 1981, 1982), as well as by fine-grained phengite.

Luisa De Capitani

Papers

Characterization of the Danube River sediments using the PMF multivariate approach

Mineralogical and geochemical spatial analyses of a waste-rock dump at the Libiola Fe–Cu sulphide mine (Eastern Liguria, Italy)

Pre-alpine and alpine evolution of the South-alpine basement of the Orobic Alps

Characterisation of Alpine lake sediments using multivariate statistical techniques

Geochemical hazard evaluation of sulphide-rich iron mines: The Rio Marina district (Elba Island, Italy)