Other systems, however, display evidence of magmatic fluid influx and correspond to intrusion-related gold systems (IRGS) (Fayol and Jébrak, 2017, Ispolatov et al., 2008, Katz et al., 2017, Robert, 2001). Gold mineralization is generally related to hydrothermal systems dominated by metamorphic fluids, referred to as orogenic gold deposits (Bateman et al., 2005, Gosselin and Dubé, 2005, Groves et al., 1998, Phillips and Powell, 2010). The Abitibi Subprovince, Canada, is a Neoarchean greenstone belt renowned for its gold endowment. Knowledge of these physico-chemical conditions are necessary to better constrain the IRGS metallogenic model. This study provides the basis for a systematic evaluation of the physico-chemical conditions within which syntectonic magmas evolved in the upper crust. The magma also formed a deep intrusion unable to provide magmatic fluids to trigger an efficient hydrothermal system. The magma had an ƒO 2 above the Ni/NiO solid oxygen buffer (NNO + 1), which is not considered optimal for Au transportation. This study also has implications for the origins of the Muscocho Pluton, which ascended slowly toward the upper crust as a single pulse of evolved magma and became emplaced at about 12 km depth. As such, this contribution uses fresh to altered granodiorites of the Muscocho Pluton, a 16 km diameter granodiorite intrusion spatially associated with polymetallic mineralization, to evaluate whether physico-chemical parameters can be retrieved from ancient altered rocks based on amphibole, apatite, and zircon chemistry. Retrieving such parameters from the metamorphosed, locally hydrothermally altered, and generally deformed Neoarchean rocks is particularly challenging.
The ƒO 2 parameter is particularly important because it affects S-speciation and S-solubility, which correlates with Au-solubility in magmas. Determining whether magmas can transport enough Au to fertilize the upper crust during this tectonomagmatic interval requires insights into physico-chemical parameters such as pressure, temperature, and oxygen fugacity (ƒO 2).
Such magma locally are associated with magmatic-hydrothermal styles of mineralization, interpreted by some works to reflect intrusion-related gold systems (IRGS). The detailed study of some biologically important structures of sand flies e.g., mouthparts and reproductive organs both internal as well as external have led to the introduction of few new taxonomic characters.The Muscocho Pluton is one of a number of syntectonic Neoarchean granodiorite intrusions formed during the main deformation phase in the Abitibi Subprovince that lead to stabilization of the Superior craton. Another important character is the genital filament/spermathecal duct ratio which could be a good point for taxonomic differentiation of male and female Phlebotominae sand flies.
Recently female external as well as internal genital structures are used for their identification. The identification of female sand flies was always found to be difficult and hence scanty work on females are available. In the early twentieth century, the use of internal structures particularly, cibarium, pharynx and spermathecae was introduced as taxonomic characters. From the start of sand fly research various methods for collection and identification were used. A wrong identification may lead to misleading results and may upset the entire control strategy. The accurate identification is important to apply relevant control measures. Taxonomy plays an important role in identifying these tiny insects accurately. These Phlebotominae sand flies are economically important natural enemies of human beings and cause Kala-azar and visceral leishmaniasis. Several species of Phlebotominae sand flies are known throughout the world including India. The aim of present study is to discuss the taxonomic and biological history and significance of Phlebotominae sand flies giving emphasis on their collection, preservation and identification of new species as well as differentiation of male and female. A Review on the Collection, Preservation and Systematic Techniques in Phlebotominae
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