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. 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. These show up as the pink spots on the image on the right. Argillic horizons and claysized particles an alternative interpretation of their dynamics in sola development and across catenas mostafa abdelssamie abdelkhalik ibrahim iowa state university follow this and additional works at.
Diamond drilling at ohio creek in 19781981 by amoco minerals intersected low grade cuau 0. Argillic and advanced argillic alteration are shallow types of alteration encountrered in a variety of different types of hydrothermal systems. The simplest means of producing these lower ph, lower temperature fluids is to interact. 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. A wellpreserved lithocap at potosi is dominated by vuggy residual quartz and contained the.
Sericitic and advanced argillic mineral assemblages. Argillic alteration is representative of supergene environments where low temperature groundwater becomes. Pdf environments of advanced argillic alteration i. Element mobility during zeolitic and argillic alteration of.
Distributions of febearing minerals, clays, micas, sulfates, and carbonates were mapped using the tetracorder spectralshape matching system. Hydrothermal alteration institute for mining geology. Pat, 2012, hydrothermal alteration in volcanogenic massive sulfide occurrence model. 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. Mineralogy and geochemistry of advanced argillic alteration zones lithocaps in greece advanced argillic alteration assemblages consisting of various amounts of quartz, diaspore, pyrophyllite. The earliest signs of argillic alteration include the bleaching out of feldspars. An understanding of hydrothermal alteration is of value because. Argillic horizon synonyms, argillic horizon pronunciation, argillic horizon translation, english dictionary definition of argillic horizon. Advanced argillic alteration forms in five various 15, mainly shallow acidic environments, producing a variety of minerals that can include kaolinite, alunite and pyrophyllite.
Major styles of mineralization and hydrothermal alteration. Mineralization and alteration of a modern seafloor massive. Silicic and argillic alterations are confined in the immediate wall rocks of the quartz veins. Spectral characteristics of propylitic alteration minerals as a. 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. Pdf documents opened from your browser may not display or print as intended. Argillic alteration is generally a low temperature event, and some may occur in atmospheric conditions. Mapping advanced argillic alteration at cuprite, nevada. Hydrothermal alteration associated with the gic includes potassic, phyllic, and advanced argillic. Argillic alteration is recognized in association with uranium deposits on the colorado. Argillic alteration grades to a propylitic zone farther.
Dec 29, 2016 hydrothermal alteration zones can be recognized upon the spectral characteristics of main mineral assemblages. 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. Mapping argillic and advanced argillic alteration in volcanic. Sericitic and advanced argillic mineral assemblages and. These areas were differentiated in order to characterize and contrast the geochemical signatures of solids and waters in a variety of mineralized areas. Gsa 2000b unusual advanced argillic alteration of the sw. The process generally occurs at low temperatures and may occur. Introduction advanced argillic alteration aaa systems have a good potential for exploration because of the close relationships with the ore deposits.
Zones of advanced argillic alteration constituting lithocaps are commonplace in the shallow parts of porphyry copper systems. In argillic and phyllic alterations minerals mostly display aloh absorption feature in 1. Pdf ree distribution and behaviour during hydrothermal alteration in three deposits is presented. 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. Sciencedirect hydrothermal alteration mapping from landsat8 data, sar. 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. Soil orders typically formed in forested regions such as alfisols or spodosols, having distinct argillic or spodic subsoil horizons, cover 12%. Argillic horizon definition of argillic horizon by the free. The process generally occurs at low temperatures and may occur in atmospheric conditions. Argillic alteration is representative of supergene environments where low temperature groundwater becomes acidic. Advanced argillic lithocaps in the bolivian tinsilver belt. Phyllic alteration is often closely associated with argillic alteration, which occurs at lower temperatures and dominantly affects plagioclase. Sericitic and advanced argillic mineral assemblages and their. Argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals.
Argillic alteration is hydrothermal alteration citation needed of wall rock which introduces clay minerals including kaolinite, smectite and illite. Journal of taibah university for science 9 2015 155166 available online at. Although enargite has been observed petrographically. 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. Geology and hydrothermal alteration of the low sulfidation payot. Argillic alteration article about argillic alteration by. Oct 07, 2017 argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals including kaolinite, smectite and illite. Hydrothermal alteration usgs publications repository. Alteration assemblages vary with depth and with degree of fluid interaction. Hydrothermal alteration mapping from landsat8 data, sar. Download the latest version of adobe reader, free of charge.
Jul 30, 2009 read element mobility during zeolitic and argillic alteration of volcanic ash in a closedbasin lacustrine environment. 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. Poorly or weakly developed soil orders such as entisols, aridisols, and inceptisols cover 38% of the ice free land surface. Advanced argillic alteration in the deeply buried magma porphyry cumo prospect, superior, alabama. Highly weathered soil orders such as ultisols and oxisols cover nearly 16%. In advanced argillic alteration mree and hree are strongly depleted while lree are immobile. They are located in the srednogorie tectonic zone, where host rocks are upper cretaceous intermediate. Porphyry cuau mineralisation, advanced argillic alteration. Role of potassic alteration for porphyry cu mineralization. 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. The occurrence of advanced argillic alteration assemblages along the ns, nnwsse, and ew. 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. Argillicadvanced argillic alteration open energy information.
Mineralogical study of the advanced argillic alteration zone. More distal and downwards, advanced argillic alteration gradually evolves into phyllic assemblages dominated by quartz and sericite. 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. Pdf mineralogical study of the advanced argillic alteration zone. Pdf timing of advanced argillic alteration at nankivel hill. Pdf the konos hill prospect in ne greece represents a telescoped mocure au porphyry occurrence. Endmember illite and rectorite is present in all samples from site d, reflecting high temperatures 220c and a progression from argillic to phyllic alteration at depth e. In this report, we assigned various geochemical data to one of the. 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. Advanced argillic alteration in the deeply buried magma. Mineral maps based on airborne visibleinfrared imaging spectrometer aviris data were used to study late miocene advanced argillic alteration at cuprite, nevada. The values of the aaai at basin lake are similar to those of several highsulfidation epithermal deposits. Argillic horizons an overview sciencedirect topics.
Hydrothermal alteration varies widely from district to district and among individual deposits, and the literature on this topic is voluminous. Mapping argillic and advanced argillic alteration in volcanic rocks, quartzites, and quartz. 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. Argillic definition of argillic by the free dictionary. Over 30 occurrences of aaa are known in bulgaria velinov et al, 2003, some of them associated with porphyry copper and epithermal deposits. Advanced argillic is a special type of alteration that. Phyllic alteration typically forms in the basemetal zone of a porphyry system. Geochemistry of hydrothermal alteration in volcanic rocks. Mapping argillic and advanced argillic alteration in volcanic rocks. However, hyperion with its fine spectral bands has potential for good separability of features. Argillic alteration is hydrothermal alteration of wall rock which introduces clay minerals including kaolinite, smectite and illite. Mineralogical study of the advanced argillic alteration. The geological setting is jurassic greywacke basement overlain by late miocene andesiticdacitic.
Mapping advanced argillic alteration zones with aster and. Mineralogy and geochemistry of advanced argillic alteration zones lithocaps in greece advanced argillic alteration assemblages consisting. Case study olduvai gorge, tanzania, chemical geology on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Pdf ree mobility during advanced argillic alteration in some. 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. Advanced argillic alteration mineral assemblages precipitate from so2 and.519 1072 311 995 997 16 852 1528 865 1557 638 1549 415 1113 1646 1124 850 260 387 192 952 1329 1317 957 1359 751 1390 1257 1379 219 604 1322