Mapping advanced argillic alteration at cuprite, nevada. Mapping argillic and advanced argillic alteration in volcanic rocks. Sericitic and advanced argillic mineral assemblages. Role of potassic alteration for porphyry cu mineralization. In argillic and phyllic alterations minerals mostly display aloh absorption feature in 1. Mapping argillic and advanced argillic alteration in volcanic rocks, quartzites, and quartz. Journal of taibah university for science 9 2015 155166 available online at. Argillic horizons an overview sciencedirect topics. Possible submarine advanced argillic alteration at the basin. Geochemistry of hydrothermal alteration in volcanic rocks. Hydrothermal alteration is a ch emical replacement of the original minerals in a rock by new minerals where a hydrothermal fluid delivers the chemical reactants and removes the aqueous reaction products. Hydrothermal alteration associated with the gic includes potassic, phyllic, and advanced argillic. Major styles of mineralization and hydrothermal alteration.
Hydrothermal alteration usgs publications repository. More distal and downwards, advanced argillic alteration gradually evolves into phyllic assemblages dominated by quartz and sericite. Sericitic and advanced argillic mineral assemblages and. May 24, 2015 argillic is often used for texturally destructive alteration that has a similar clayrich mineralogy, and which occurs in and around structures in the upper parts of porphyry systems. Hydrothermal alteration mapping from landsat8 data, sar.
Argillic horizon synonyms, argillic horizon pronunciation, argillic horizon translation, english dictionary definition of argillic horizon. Hydrothermal alteration institute for mining geology. Distributions of febearing minerals, clays, micas, sulfates, and carbonates were mapped using the tetracorder spectralshape matching system. Alteration assemblages vary with depth and with degree of fluid interaction.
Introduction advanced argillic alteration aaa systems have a good potential for exploration because of the close relationships with the ore deposits. Argillic and advanced argillic alteration are shallow types of alteration encountrered in a variety of different types of hydrothermal systems. Diamond drilling at ohio creek in 19781981 by amoco minerals intersected low grade cuau 0. Argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals. Advanced argillic alteration in the deeply buried magma.
Argillic horizon definition of argillic horizon by the free. A quantitative approach to genetic issues of argillic and propylitic alteration zones of epithermal cupbfe deposits related to andesitic magmatism khan kandi district, nw iran. Argillic alteration grades to a propylitic zone farther. Argillic alteration is representative of supergene environments where low temperature groundwater becomes. However, hyperion with its fine spectral bands has potential for good separability of features. Mineralization and alteration of a modern seafloor massive.
Porphyry cuau mineralisation, advanced argillic alteration. Argillic alteration is recognized in association with uranium deposits on the colorado. Advanced argillic alteration in the deeply buried magma porphyry cumo prospect, superior, alabama. The process generally occurs at low temperatures and may occur in atmospheric conditions.
Argillic horizons and claysized particles an alternative. Argillic alteration is representative of supergene environments where low temperature groundwater becomes acidic. This genetic framework of environments of formation of advanced argillic alteration helps to interpret alteration mineralogy plus its morphology and zonation during exploration and assessment of. Advanced argillic alteration forms in five various 15, mainly shallow acidic environments, producing a variety of minerals that can include kaolinite, alunite and pyrophyllite. The dating of alunite from an area of advanced argillic alteration at nankivel hill provides new data on the timing of hydrothermal fluid activity that links with the c. Mapping argillic and advanced argillic alteration in volcanic rocks, quartzites, and quartz arenites in the western richfield 1 x 2 quadrangle, southwestern utah, using aster satellite data. These areas were differentiated in order to characterize and contrast the geochemical signatures of solids and waters in a variety of mineralized areas. Poorly or weakly developed soil orders such as entisols, aridisols, and inceptisols cover 38% of the ice free land surface. Mapping advanced argillic alteration zones with aster and. Phyllic alteration is often closely associated with argillic alteration, which occurs at lower temperatures and dominantly affects plagioclase. Pla 1997, modeling a slope characteristic of the western andes of venezuela, found that simple reforestation of a degraded pasture was not sufficient to prevent landslideshydraulic conductivity was so low in the argillic horizon of ultisols that drainage ditches were required to prevent saturationinduced translational failure. Pdf documents opened from your browser may not display or print as intended.
Mineralogical study of the advanced argillic alteration. Phyllic alteration and argillic advanced argillic assemblages are derived from increasing acidic hydrothermal fluids generally of lower temperature than common for potassic and propylitic assemblages. Zones of advanced argillic alteration constituting lithocaps are commonplace in the shallow parts of porphyry copper systems. Similar lithocaps are also recognized in the shallowly eroded southern part of the bolivian tinsilver belt, where mineralization typically is centred on felsic volcanic domes. Geology and hydrothermal alteration of the low sulfidation payot. Mineralogy and geochemistry of advanced argillic alteration zones lithocaps in greece advanced argillic alteration assemblages consisting. Pdf timing of advanced argillic alteration at nankivel hill. Pdf ree distribution and behaviour during hydrothermal alteration in three deposits is presented. They are located in the srednogorie tectonic zone, where host rocks are upper cretaceous intermediate.
In this report, we assigned various geochemical data to one of the. Sciencedirect hydrothermal alteration mapping from landsat8 data, sar. Advanced argillic lithocaps in the bolivian tinsilver belt. The earliest signs of argillic alteration include the bleaching out of feldspars. The grasberg cuau porphyry deposit in irian jaya, indonesia, is one of the largest cuau deposits in the world, and manifests a range of alteration types that extend from potassic to advanced argillic. Mineralogy and geochemistry of advanced argillic alteration zones lithocaps in greece advanced argillic alteration assemblages consisting of various amounts of quartz, diaspore, pyrophyllite. The geological setting is jurassic greywacke basement overlain by late miocene andesiticdacitic. Pat, 2012, hydrothermal alteration in volcanogenic massive sulfide occurrence model. Argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals including kaolinite, smectite and illite.
The values of the aaai at basin lake are similar to those of several highsulfidation epithermal deposits. In advanced argillic alteration mree and hree are strongly depleted while lree are immobile. Argillic alteration is hydrothermal alteration citation needed of wall rock which introduces clay minerals including kaolinite, smectite and illite. Gsa 2000b unusual advanced argillic alteration of the sw. Argillicadvanced argillic alteration open energy information. A wellpreserved lithocap at potosi is dominated by vuggy residual quartz and contained the.
For best results viewing and printing pdf documents, it is recommended that you download the documents to your computer and open them with adobe reader. Over 30 occurrences of aaa are known in bulgaria velinov et al, 2003, some of them associated with porphyry copper and epithermal deposits. Download the latest version of adobe reader, free of charge. These images from my earlier talk on porphyry exploration, with exploration for high sulfidation systems were looking for the same sort of alteration as with porphyries, in other words silicic, argillic and advanced argillic silicification. Nor is there a zonation of oxygen isotopic compositions that would be predicted for intrusiondriven waterrock interactionmagmatic fluids near the intrusive centres followed progressively outwards by sup. Pdf ree mobility during advanced argillic alteration in some. The deeper part of the ore body, where potassic alteration dominates, is nearly arsenicfree, whereas the upper part of the copper ore body is arsenicbearing. Argillic definition of argillic by the free dictionary. Soil orders typically formed in forested regions such as alfisols or spodosols, having distinct argillic or spodic subsoil horizons, cover 12%.
Phyllic alteration typically forms in the basemetal zone of a porphyry system. Highly weathered soil orders such as ultisols and oxisols cover nearly 16%. Jul 30, 2009 read element mobility during zeolitic and argillic alteration of volcanic ash in a closedbasin lacustrine environment. Argillic alteration article about argillic alteration by. Mapping argillic and advanced argillic alteration in volcanic. Sericitic and advanced argillic mineral assemblages and their. Silicic and argillic alterations are confined in the immediate wall rocks of the quartz veins. Zunyite, along with various amounts of quartz, alunite, aluminum phosphatesulfate minerals aps, diaspore, kaolinite, and minor pyrophyllite, are the main minerals in the advanced argillic alteration. The process generally occurs at low temperatures and may occur. Oct 07, 2017 argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals including kaolinite, smectite and illite. Dec 29, 2016 hydrothermal alteration zones can be recognized upon the spectral characteristics of main mineral assemblages. Pdf the konos hill prospect in ne greece represents a telescoped mocure au porphyry occurrence. The occurrence of advanced argillic alteration assemblages along the ns, nnwsse, and ew.
These show up as the pink spots on the image on the right. Argillic alteration is generally a low temperature event, and some may occur in atmospheric conditions. Mineral maps based on airborne visibleinfrared imaging spectrometer aviris data were used to study late miocene advanced argillic alteration at cuprite, nevada. Spectral characteristics of propylitic alteration minerals as a. Pdf mineralogical study of the advanced argillic alteration zone. Advanced argillic is a special type of alteration that. The simplest means of producing these lower ph, lower temperature fluids is to interact. The spectral angle mapper algorithm was used in this study to map three advanced argillic alteration minerals alunite, kaolinite, and dickite in a known alteration zone in the peruvian andes. Hydrothermal alteration varies widely from district to district and among individual deposits, and the literature on this topic is voluminous. An understanding of hydrothermal alteration is of value because. Pdf environments of advanced argillic alteration i.
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