That was a quote not the translation : "" of semi-massive chalcopyrite hosted within hematitic and potassic altered greywackes. ""
Chalopyrite is COPPER
HEMATITIC is IRONs
POTASSIC i have not clue it is either a new movie called Potassic PARK or and era I never heard of OR something to do w potassium, eat a bananna, then let half turn grey with iron oxidation, ie RUST of Hematitic Irons and aftera while if u get the erge, GREYWACKES the old bananna. Other than that GOOD the words: 1 HEMATITIC- http://geology.geoscienceworld.org/cgi/content/abstract/31/4/319 "" Paleozoic and Mesozoic silica-rich seawater: Evidence from hematitic chert (jasper) deposits Tor Grenne*,1 and John F. Slack2 1 Geological Survey of Norway, Leiv Eirikssons vei 39, N-7491 Trondheim, Norway 2 U.S. Geological Survey, National Center, MS 954, Reston, Virginia 20192, USA
Laterally extensive beds of highly siliceous, hematitic chert (jasper) are associated with many volcanogenic massive sulfide (VMS) deposits of Late Cambrian to Early Cretaceous age, yet are unknown in analogous younger (including modern) settings. Textural studies suggest that VMS-related jaspers in the Ordovician Løkken ophiolite of Norway were originally deposited as Si- and Fe-rich gels that precipitated from hydrothermal plumes as colloidal silica and iron-oxyhydroxide particles. Rare earth element patterns and Ge/Si ratios of the jaspers reflect precipitation from plumes having seawater dilution factors of 103 to 104, similar to modern examples. We propose that silica in the ancient jaspers is not derived from submarine hydrothermal fluids—as suggested by previous workers—but instead was deposited from silica-rich seawater. Flocculation and precipitation of the silica were triggered inorganically by the bridging effect of positively charged iron oxyhydroxides in the hydrothermal plume. A model involving amorphous silica (opal-A) precursors to the jaspers suggests that silica contents of Cambrian–Early Cretaceous oceans were at least 110 mg/L SiO2, compared to values of 40–60 mg/L SiO2 estimated in other studies. The evolution of ancient silica-rich to modern Fe-rich precipitates in submarine-hydrothermal plumes reflects a changeover from silica-saturated to silica-depleted seawater through Phanerozoic time, due mainly to ocean-wide emergence of diatoms in the Cretaceous.
POTASSIC 2 - last line quote TO TRANSPORT METALS IN ORE DEPOSITES! Weee: http://petrology.oxfordjournals.org/cgi/content/full/41/12/1822 "" Potassic Igneous Rocks and Associated Au–Cu Mineralization, 3rd edn, by D. Müller and D. I. Groves. Springer Verlag, Berlin, 2000. xiii + 252 pp. ISBN 3540663711. £44.50, US$79.95 Potassium-rich igneous rocks are one of the most intriguing study subjects in igneous petrology and geochemistry. They show a very wide range of composition, from mildly potassic shoshonitic suites associated with calcalkaline magmas in arc environments to ultrapotassic leucitites, kamafugites and lamproites. Major, trace element and isotopic compositions are very variable, although all show high to extreme enrichment in several trace elements, such as Th, U, Rb, Ba and LREE. Potassic and ultrapotassic rocks occur in various tectonic settings, from island arcs and convergent continental margins to cratonic areas. They also have an economic interest, as they may be associated with mineralization and may host precious minerals, such as the case of diamond-bearing lamproites. Because of all these factors, potassic rocks have attracted the attention of petrologists, geochemists and economic geologists. Yet, books on these rocks are virtually lacking. The book by Müller and Groves fills this gap by giving a review of classification, genesis, tectonic settings and economic aspects of potassic rocks. The book basically consists of two parts; in the first half (Chapters 1–4), the authors elucidate the aspects related to nomenclature, tectonic setting and petrogenesis of potassic rocks, and provide a short description of the main type localities from various tectonic settings. In the second part of the book (Chapters 5–19), the economic aspects are reviewed, placing emphasis on the association of potassic rocks with Au–Cu mineralizations.
Chapter 1 is an overview of the main compositional characteristics of potassic and ultrapotassic rocks, their nomenclature and mode of occurrence. Chapter 2 focuses on the tectonic setting of potassic rocks. Here, the authors show how some of the classical trace element discriminant diagrams do not work for potassic magmas and a new hierarchical scheme is erected to discriminate among potassic rocks from various tectonic environments, including continental arcs, postcollisional arcs, initial and late oceanic arcs and within-plate settings. Chapter 4 is a short description of selected type localities of potassic rocks from the five tectonic settings. Here, the Central Africa Rift Valley occurrence is used as an example of intraplate potassic magmatism, even though these rocks were not considered in Chapter 3, when the database was built up.
Chapters 5–7 face the controversy regarding the relative contribution of magmatic vs metamorphic and crustal vs mantle origin of fluids responsible for transport of precious metals associated with potassic magmatism. Relevant case histories of direct and indirect association between potassic rocks and Au–Cu deposits are described. The considered occurrences cover a wide range of ages and tectonic settings, from the Archaean mesothermal gold mineralizations of the Superior province (Canada) and Western Australia, to the Eocene Bingham (Utah) porphyry copper deposit, Miocene epithermal gold mineralizations of El Indio (Chile) and Pliocene–Quaternary mineralizations of Papua New Guinea. For each occurrence, information on age and nature of mineralization, regional geology, and age, petrology and geochemistry of associated potassic rocks are given.
Chapter 8 contains a short but informative discussion on the behaviour of halogens (F, Cl) in magmatic systems during partial melting and fractional crystallization, and on the role of halogen-rich fluids for the transport of metals in ore deposits related to potassic rocks. Particular attention is devoted to the role of redox conditions of magmas and mantle sources in determining the behaviour of these elements and their capability to transport metals.
Graywacke 3- http://en.wikipedia.org/wiki/Graywacke "" Greywacke (German grauwacke, signifying a grey, earthy rock) is a variety of sandstone generally characterized by its hardness, dark color, and poorly-sorted, angular grains of quartz, feldspar, and small rock fragments set in a compact, clay-fine matrix. It is a texturally-immature sedimentary rock generally found in Palaeozoic strata. The larger grains can be sand-to-gravel-sized, and matrix materials generally constitute more than 15% of the rock by volume.
The origin of greywacke was problematic prior to the understanding of turbidity currents and turbidites since, according to the normal laws of sedimentation, gravel, sand and mud should not be laid down together. Currently geologists attribute its formation to submarine avalanches or strong turbidity currents. These actions churn sediment and cause mixed-sediment slurries to occur. When this is the case, the rocks may exhibit a variety of sedimentary features. Support for the turbidity current origin is the fact that deposits of greywacke are found on the edges of the continental shelves, at the bottoms of oceanic trenches, and at the bases of mountain formational areas. It also occurs in association with black shales of deep sea origin.
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