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Early Cretaceous carbonates are the most common host rocks for Irish-type deposits in Iran. They are largely concentrated in the Malayer-Esfahan metallogenic belt (MEMB) in southwestern Iran, and Yazd-Anarak metallogenic belt in Central Iran. They include some world-class ore deposits such as Mehdiabad, Irankuh, and Ahangaran. These stratabound deposits are hosted mostly in carbonates with minor siltstones and volcanic compo-nents, that formed in extensional and passive margin environments that are related to the Nain-Baft back-arc basin. The deposits are stratabound and comprise wedge-shaped to tabular sulphide-barite orebodies and occur in several different stratigraphic horizons. Dolomitization and silicification are the main wall-rock alteration styles. Replace-ment textures are common, and orebodies represent complex textures of sulphides and barite, such as brecciated, colloform, zebra, minor laminated, and banded replacement. Barite is an important gangue mineral in the MEMB and YAMB deposits, partly replaced by coarse-grained galena, sphalerite, and chalcopyrite. Sulphides from these Irish-type deposits have a wide spread of light d34S values (with the majority falling between -25 to +5‰) with mostly bacterial sulphate reduction (BSR) origin. Fluid inclusion studies show that homogenization temperatures of ore minerals are typically 120 to about 280°C (majority 225-275°C), and salinities range from 2 to 24 wt.% NaCl eq, with the majority falling between 8 and 22 wt% NaCl eq. Using the criteria outlined in this study, early Cretaceous extensional sedimentary basins (e.g., Nain-Baft) are highlighted as target areas for exploration of world-class Irish-type ore deposits and correspond well with the periods of expulsions of Cretaceous CaCl2-rich brines., Peer Reviewed, Postprint (published version)

The Mehdiabad deposit in the Yazd-Anarak metallogenic belt (YAMB), central Iran, is the largest car-bonate-hosted Zn-Pb-Ba-Cu (-Ag) deposit in the world, with a reserve of 630 Mt sulphide and non-sulphide ore. It was formed during the Early Cretaceous by the replacement of barite and hydrothermally dolomitized breccia bod-ies of the Taft and Abkuh formations. This deposit consists of different ore zones, including the feeder zone, massive ore (including sulphide-oxide parts), massive barite ore, and copper-rich sulphide-barite ore, formed in an exten-sional environment related to the Naein-Baft back-arc basin. The deposit is stratabound and comprises a wedge-shaped sulphide-barite orebody with complex replacement textures of sulphides and barite. The primary sulphide ore, including a copper-rich core (with a reserve of more than 50 Mt of copper ore), developed in a barite sheath and characterized by the replacement of barite and pyrite by an assemblage of chalcopyrite, bornite, sphalerite and galena. Several stages of barite and sulphide deposition in the Mehdiabad deposit are similar to those reported in other Irish-type and barite-replacement sediment-hosted Zn-Pb deposits worldwide (e.g., Red Dog deposit, Alaska, USA)., Peer Reviewed, Postprint (published version)

To assess the social perception of landscapes in Hidalgo state (Mexico), we developed a digital questionnaire that was answered by 197 people (mostly students) from two high-school centers located in the ‘Comarca Minera’ UNESCO Global Geopark. The preferred landscape site from Hidalgo is ‘Prismas Basálticos’, the emblematic geosite of the geopark. This geosite, also, raises most concerns for its conservation. Huasca de Ocampo, Mineral del Monte and Mineral del Chico are the preferred municipal areas mentioned; these possess the touristic brand as ‘Pueblos Mágicos’ (Magic Towns). On the other hand, a conspicuous preference for forests and mountains is observed, distinctive features of Hidalgo landscapes. Questionnaire results do not reflect a link of landscape preference to age, genre, environment (urban or rural) nor home municipality, whereas academic category (student or teacher) and birthplace (Hidalgo or elsewhere) played a role in the preferences. A pronounced difference is that those born in Hidalgo refer to a wider variety of sites, reflecting a greater knowledge of the territory. In terms of geopark meanings, manifested emotions relate to conservation values, care and protection of land, but also to other attributes, among which geology is the most cited., Para evaluar la percepción social de los paisajes de Hidalgo, se desarrolló un cuestionario electrónico que se aplicó en dos instituciones de enseñanza media superior del Geoparque ‘Comarca Minera’. El tamaño de la muestra fue de 197 individuos (116 corresponden a una escuela rural y 81 a una urbana). El sitio preferido por su paisaje es el geositio emblemático ‘Prismas Basálticos’. Éste aparece también como el que más preocupa por su conservación. Huasca de Ocampo, Mineral del Monte y Mineral del Chico son las entidades preferidas; los tres son municipios del geoparque con la designación turística de ‘Pueblos Mágicos’. También se observa una preferencia por bosques y montañas, elementos característicos de los paisajes hidalguenses. El cuestionario no reflejó un peso de los factores edad, género, ambiente urbano o rural y municipio de residencia sobre la selección de los paisajes, mientras que la categoría académica (estudiante o docente) y el lugar de nacimiento sí tuvieron efecto. La diferencia más acusada es que los nacidos en Hidalgo mencionan más sitios. En cuanto al significado del geoparque, se manifiestan emociones relacionadas con valores de conservación y protección del territorio, así como con distintos atributos, entre los cuales la geología es el más mencionado.

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© 2021. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, The Hossein-Abad and Western Haft-Savaran Zn-Pb SEDEX deposits are located in the Arak basin of the Malayer-Esfahan Metallogenic Belt, Iran. This metallotect formed in a back-arc paleotectonic setting as a result of the subduction of the Neo-Tethys oceanic plate beneath the Sanandaj-Sirjan Zone. The rocks that host the mineralization are Jurassic organic matter-bearing, fine-grained sandstones, siltstones and shales. Asymmetric lenticular bedding, unidirectional flow (based on oblique silt lamination direction relative to horizontal bedding), graded bedding and clay-rich interbeds indicate sediments were deposited from turbidity currents in a low-energy basin environment. There are three ore facies in the Hossein-Abad and Western Haft-Savaran Zn-Pb deposits: 1) bedded ore; 2) massive ore; 3) feeder zone. Bedded ore contains pyrite framboids and polyframboidal clusters. The size range of the pyrite framboids (3 to 6 µm in diameter) indicates they formed in the water column and not in the subsurface. Characteristic structures in bedded ore are: 1) sulfide-bearing silt injections into clay-filled burrows 2) injection of sulfide-bearing silt into flame structures of claystone laminae, and 3) organic matter in claystone oriented oblique relative to bedding. These structures are the result of seismic deformation induced by synsedimentary earthquakes, whereby sulfides that formed in permeable unconsolidated sediment were injected into organic matter-bearing claystone unit. The d18O and d13C values of siderite, calcite and dolomite in veins from the feeder zone and massive ore range from 12.2 to 23.8 ‰ and -16.7 to 1.7 ‰, respectively. These values indicate that formational water, seawater and organic matter oxidationdecomposition all played a role in hydrothermal carbonate formation. Melting and homogenization temperatures for CO2 for CO2-bearing fluid inclusions range from -57.5 to -60 °C and 6.6 to 29.5 °C, respectively, and indicate the presence of <15 mol % CH4. The CO, Tarbiat Modares University of Tehran provided financial support for this research. The Serveis Científico-Tècnics of the Universitat de Barcelona, Spain, provided support for the sulfur isotope analyses and the Catalan Government’s Department of Universities, Research and the Information Society provided financial assistance under research grant 2017SGR0707 of the Generalitat de Catalunya. We thank Brian Pratt of the University of Saskatchewan for invaluable assistance in identifying and interpreting sedimentary textures. We thank Suzanne Paradis and Micheal Gadd (GSC) for reviewing an earlier draft of the manuscript. Peter thanks the Targeted Geoscience Initiative Program of the Geological Survey of Canada (GSC) for logistical support. This is GSC contribution number XXXXXXXXX, Peer Reviewed, Postprint (author's final draft)

En este trabajo se infieren los mecanismos de transporte y movilidad del mercurio en el sistema geotérmico Araró-Simirao, que se asocian a un sistema de fallas de tipo normal y orientación general NE-SW, a través de la modelación hidrogeoquímica del Hg en agua y suelos y su relación con la concentración de Hg en el aire. Se realizó un muestreo de agua termal y suelos, y se comparó con las emanaciones de gases de mercurio elemental. Las especies predominantes de Hg en agua son Hg0(ac), HgCl2 y HgCl3-, aunque la abundancia de Hg0 (ac) es menor con respecto a Hg2+. En suelo se encontraron minerales de alteración hidrotermal como barita y partículas con contenidos de Hg. De forma general, se deduce que los procesos geoquímicos que se llevan a cabo para el transporte de Hg entre los compartimentos ambientales agua, suelo y atmósfera son: volatilización, oxidación, complejación y depósito. El sistema hidrotermal a profundidad favorece el transporte de mercurio elemental en estado gaseoso, de probable origen magmático, hacia la superficie por las zonas de mayor permeabilidad, como es la falla Araró-Simirao; en su ascenso interacciona con el acuífero sub-superficial, enriqueciéndolo en Hg y formando complejos clorurados que son transportados en el medio acuoso. Al descargarse a la superficie el agua termal enriquecida en Hg, éste se volatiliza como Hg0(g) y permanece en la atmósfera o puede depositarse en los suelos aledaños a los manantiales, adhiriéndose a partículas de materia orgánica o arcillas y formando aureolas de anomalías de Hg en superficie. De acuerdo con la distribución espacial de estas aureolas, la zona más cercana a los fluidos geotérmicos (ascenso vertical de los gases) es la parte sur del sistema

The Velardeña mining district is economically the most important of Durango state. The ore deposits occur in different skarn zones developed within the intrusive contact between Mesozoic limestones and Eocene granitic stocks and dikes. The most important ore deposits are related to the Santa María dike and Reyna de Cobre porphyritic stock (separated from each other by 10 km). They occur as irregularly shaped replacement masses developed near the intrusive contact and have a skarn paragenesis dominated by calc-silicates and sulfides. The mineral assemblages show replacement textures and are dominated by calcic clinopyroxene (Di97-53Hd42-02Jh04-01) and garnet (Ad100-57Grs43-00) in the exoskarn, with wollastonite particularly abundant in the endoskarn. Hydrous silicates are actinolite, epidote, and chlorite, whereas sulfides include pyrite, sphalerite, pyrrhotite, galena, chalcopyrite, and sulfosalts. Scheelite, hematite, quartz, and calcite are also present. According to sphalerite geobarometry, the skarns formed at hypabyssal depths (~3–4 km). They developed by a succession of replacive mineralizing events, including (a) a prograde stage at temperatures from =470 to 335 °C in conditions of low f(CO2), followed by (b) a retrograde stage from 335 to 220 °C. There was a general increase in f(O2), accompanying the temperature decline during the formation of the system, which accounts for a process of mixing with cooler, oxidizing, and dilute water. During the retrograde stage, wollastonite calcic garnet and clinopyroxene formed. On the other hand, hydrous silicates, sulfides, sulfosalts, scheelite, and hematite crystallized during the retrograde stage. Skarn mineralization is crosscut by veins of calcite, fluorite, adularia, and sphalerite. The vein mineralization formed at temperatures below 200 °C. The different ore deposits of Velardeña constitute a telescoped skarn–epithermal mineral system., This project was sponsored by Industrias Peñoles, S.A. de C.V., and the stable isotope measurements were supported by the Catalan project 2014-SGR-1661. The SEM-EDS and WDS analyses and BSE images were obtained with the assistance of Carlos Linares. Teresa Pi Puig is thanked for the XRD analyses. We thank Thomas Bissig, Bernd Lehmann, Teresa Ubide and Lisard Torró i Abat and for helpful comments on the manuscript. We also thank the anonymous reviewers for constructive comments., Peer Reviewed, Postprint (published version)

© 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, Manganese mineralization at Montaña de Manganeso, San Luis Potosí state, consists of oxide ores that form sharp contacts with volcanic host rocks. The orebodies are generally in the form of veins and irregular masses, and locally as mineralized breccias. Petrographic analyses indicate that the mineralization is multi-episodic, with colloform and crustiform textures predominating. The X-ray diffraction and electron microscopy show that manganese oxides (todorokite, birnessite, pyrolusite, romanechite and cryptomelane) are the main ore minerals, while iron oxides (goethite and hematite) are accessory. The most common gangue minerals are calcite and quartz with subordinate amounts of barite. According to fluid inclusion microthermometry, the mineralization is associated with aqueous solutions of intermediate salinity (8–16 wt% NaCl equivalent) and temperatures between 101 and 140 °C. Stable isotope analysis of calcite (d13CPDB: -7.76 to -6.32‰; d18OPDB: -8.01 to -4.71‰) and barite (d34S: 7.9–13.6‰) shows a contribution of magmatic volatiles to hydrothermal fluids dominated by meteoric water (calculated d18Ofluid: 6.58–13.14‰, relative to SMOW). Argillic alteration is the most widespread hydrothermal alteration at Montaña de Manganeso and indicates fluid temperature below ~150 °C and near neutral pH. Much more local, advanced argillic alteration, revealed by the occurrence of kaolinite, is interpreted as a steam-heated overprint, which in turn suggests a boiling process that must have happened at greater depths. The Mn ores formed through a process of mixing of: (a) boiled-off hydrothermal fluids, with (b) cold, diluted meteoric water. Our results support a hot-spring deposit model, according to which Montaña de Manganeso corresponds to the shallowest portion of an epithermal system formed in a continental volcanic arc setting., This work was supported by the PAPIIT (DGAPA, UNAM) project IG100116 and forms part of J.M’s PhD dissertation. Carlos Linares López is thanked for the assistance in WDS analyses. Edith Cienfuegos Alvarado and Francisco Javier Otero Trujano are thanked for the carbon and oxygen isotopic analyses. Colleagues Andrea Hernandez Cervantes, Irvin González Romo and Urenia Navarro are thanked for their help during fieldwork and preparation of graphics. Prof. Nicolas Johannes Beukes is greatly thanked for access to the Central Analytical Facility of the University of Johannesburg were SEM imagery was carried out. We would also like to thank the three anonymous reviewers whose comments greatly improved the manuscript., Peer Reviewed, Postprint (author's final draft)

© 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, The Koushk Zn-Pb deposit is the largest known and least deformed and non-metamorphosed Early Cambrian shale-hosted massive sulfide (SHMS) deposit at Central Iran. The current remaining reserves are estimated to be greater than 14 Mt ore, averaging 7% Zn and 1.5% Pb; the primary resources ore of the deposit is estimated to be more than 60 Mt. At this deposit, different hydrothermal ore styles (bedded ore, vent complex, and feeder zone) are well preserved within the Lower Cambrian black siltstones and shales. According to fluid-rock interaction and different ore-forming processes in SHMS systems, these ore facies with extensive hydrothermal alteration provide unique conditions to understand critical textural and geochemical frameworks to present a genetic model. In this research, we focus on different paragenetic stages of sulfide mineralization and fluid-rock interactions in different ore styles from the Koushk SHMS deposit. The paragenetic relationship provides the context for the interpretation of stable isotopes (S, C, and O) in hydrothermal sulfides and carbonates. Detailed petrography and paragenetic studies represent three major generations of sulfide mineralizations at different ore zones: (1) stage I includes very fine-grained (<6 µm) framboids, spherulite pyrite (py1), associated with minor fine-grained disseminated sphalerite (sp1), and galena (gn1); (2) Stage II is composed of a diagenetic intergrowth of coarse-grained framboids and spherulite pyrite, packed polyspherulite aggregates and pyrite nodules (py2) replacing diagenetic barite and carbonate nodules, and are followed with coarse-grained sphalerite (sp2) and galena (gn2) that replace former sulfides and barite, deposited as disseminated, laminated and sulfide-rich banded textures; (3) stage III of sulfide mineralization is characterized by vent complex development (VCD) over the feeder zone, hydrothermal brecciation, dissolution of rock-forming minerals, and extensive replacement of earlier sulfides, To memorialize one of the first author’s best teachers, Donald F. Sangster, for the love and support, and for the guidance and patience in dealing with the many problems arose during this and other projects about the sediment-hosted Zn-Pb deposits of Iran, from 2007 to 2018. The Serveis Científico-Tècnics de la Universitat de Barcelona and the research grant 2009SGR-00444 of the Departament d’Universitats, Recerca i Societat de la Informació (Generalitat de Catalunya) supported sulfur isotope analyses. The Instituto de Geofísica and Instituto de Geología of the Universidad Nacional Autónoma de México (UNAM) supported electron microprobe analyses, which were done with the assistance of Carlos Linares, and carbon and oxygen isotopes analyses. The authors thank Bafq Mining Company (BMC) for allowing access to the deposit and providing invaluable support on-site through access underground exposures. We sincerely thank Jan Peter for his helpful comments and advice, and discussions on the geology of Central Iran. The manuscript has benefited from helpful comments by David Lentz and an anonymous reviewer, and careful editorial handling by Maria Boni and Huayong Chen., Peer Reviewed, Postprint (author's final draft)

The Ab-Bagh clastic- and carbonate-hosted stratabound and stratiform Zn-Pb deposit in the Sanandaj-Sirjan zone, in the southeastern corner of the Malayer-Esfahan metallogenic belt of Iran, is typical of several sedimentary–exhalative (SEDEX) deposits in this metallogenic belt. The deposit is hosted in a late Jurassic-early Cretaceous sedimentary sequence. Based on position, there are two Zn-Pb-bearing stratigraphic ore horizons. Ore horizon 1 is hosted by late Jurassic-early Cretaceous black shale and siltstone. The wedge-shaped ore body is located close to a synsedimentary normal fault. Petrographic studies indicates that mineralization comprises three sulfide ore facies: stockwork, bedded and massive ore facies. Ore horizon 2 occurs in early Cretaceous carbonates and comprises a massive-replacement ore facies that is concordant with host rock layering; it is also underlain by a stockwork facies. Textures include framboidal, laminated, breccia, replacement, massive and vein-veinlet. Hypogene sulfide minerals are predominantly sphalerite, galena, pyrite and chalcopyrite. Calcite and quartz are major gangue minerals. Silicification and carbonatization are the main wallrock alteration styles; alteration intensity increases towards the feeder zone. Based on relationships between ore minerals and rock-forming minerals, sulfide mineralization in the Ab-Bagh deposit formed during two main stages: fine-grained sulfide bands (stage I) are intricately interlayered with organic matter-rich beds of black shale and siltstone. Sulfide bands exhibit classic sedimentary textures, such as laminations and bedding, indicative of a synsedimentary origin. Coarser-grained stage II base metal sulfides show breccia and vein-veinlet textures, and are considered to have formed by replacement during sub-seafloor fluid flow. Fluid inclusion microthermometry was carried out on calcite associated with sulfides of the stockwork ore facies. Homogenization temperatures are in the range of 180–301¿, This research was made possible by the help of the office of vice-chancellor for Research and Technology, Tarbiat Modares University (TMU) of Tehran. Strontium isotope analyses were sponsored by the National Natural Science Foundation of China (91855214, 41773043, 41320104004, 41773042), and conducted by Yu-cai Song at the Institute of Geology, Chinese Academy of Geological Sciences, Beijing, China. Sulfur isotope analyses were funded by the Catalan Government project 2014-SGR-1661. Comments and suggestions from Prof. Hooshang Asadi Haroni and Prof. Jan Matthias Peter greatly improved the quality of the paper., Peer Reviewed, Postprint (published version)

The Malayer-Esfahan Metallogenic belt (MEMB), southwestern Iran, contains numerous different types of the sediment-hosted Zn-Pb (±Ba±Ag), volcanic-sediment hosted Zn-Pb ± Ba, sideritic Fe-Mn-Pb (±Ba±Cu), and barite mineralizations. These deposits are hosted mostly in Jurassic shales and sandstones and in Early to Late Cretaceous carbonates and siltstones with minor volcanic rocks. In contrast to the orogenicrelated Mississippi Valley type (MVT) deposits, the MEMB deposits formed in an extensional back-arc environment and are characterized by their stratabound and stratiform orebodies. In these deposits, silicification and dolomitization (±sericitization) are the main wall-rock alteration styles. The presence of primary laminated sulfides, fine-grained disseminated sphalerite and galena in association with framboidal pyrite, sedimentary structures in sulfide laminae and bands, and the association of some tuffaceous and volcanic rocks with sulfide mineralizations, along with replacement ore textures in the MEMB deposits are not compatible with orogenic-related MVT model for these mineralizations. These characteristics in the Cretaceous MEMB deposits are more compatible with a sub-marine hydrothermal system with sub-seafloor replacement mineralization. Some deposits also share characteristics between Irish type and volcanogenic massive sulfide (VMS) deposits, called VSHMS in this paper. The main argument against the MVT model of Karimpour and Sadeghi (2018) is that this model is not acceptable for the MEMB deposits and could not explain metallogenic aspects of the Zn-Pb (±Ba±Ag) and other mineralizations in this belt., We thank prof. Stefano Albanese, chief editor of Journal of Geochemical Exploration, and two anonymous reviewers for their very useful and constructive comments. The authors are grateful to S. Rezaei for her help in creating the GIS data base of SH Zn-Pb deposits of Iran., Peer Reviewed, Postprint (author's final draft)

The Santa Fe mining district is located in the Central Andean tin belt of Bolivia and contains several SnZn-Pb-Ag deposits. From the economic point of view, the most important deposits of the district are Japo, Santa Fe and Morococala. Beyond the traditional metal commodities, the Central Andean Tin Belt could become an exploration target for indium, owing to the potential of the ore-bearing paragenesis with high concentrations of this technology-critical element. In the Santa Fe mining district, the ore occurs as two main types: (a) Sn-rich cassiterite-quartz veins, and (b) Zn-Pb-Ag veins with sphalerite, galena and stannite mineral phases. The In content in igneous rocks is between 1.5 and 2.5 ppm, whereas in the ore concentrate it attains up to 200 ppm. The 1,000×In/Zn ratio in concentrate ranges from 25 up to 4,000. Exceptionally high In values were found in sakuraiite from Morococala deposit (2.03 wt%). Sakuraiite in this deposit shows evidences for a link between stannite and kësterite trend of solid solutions. There is a noteworthy exploration potential for strategic metals in this district and even in similar deposits elsewhere in the Central Andean tin belt., Peer Reviewed, Postprint (published version)

Authigenic carbonate crusts, surface muds and bivalve shell fragments have been recovered from inactive and active recently discovered cold seep sites in central Guaymas Basin. In this study, for first time, redox conditions and fluid sources involved in mineral precipitation were investigated by analyzing the mineralogy and textures of surface samples, along with skeletal contents, and C, O and S isotopes variations. The d13C values of aragonitic bivalve shells and non-skeletal carbonate from some surface muds (1‰ to -3.7‰ V-PDB) suggest that carbonate precipitated from ambient dissolved inorganic carbon, whereas fibrous aragonite cement and non-skeletal carbonate from other sites are highly depleted in 13C (down to -47.6‰ V-PDB), suggesting formation via anaerobic oxidation of methane, characteristic of methane seepage environments. d18O in most of the carbonates varies from +1.4‰ to +3.2‰ V-PDB, indicating that they formed from slightly modified seawater. Some non-skeletal carbonate grains from surface muds have lower d18O values (-12.5‰ to -8.2‰ V-PDB) reflecting the influence of 18O-depleted pore water. Size distribution of pyrite framboids (mean value: 3.1¿µm) scattered within diatomaceous sinter suggests formation from anoxic-sulfidic bottom waters. d34S in pyrite is of -0.3‰ V-CDT compared to +46.6‰ V-CDT in barite, thus implying a fluid sulfate-sulfide fractionation of 21.3‰ that argues in favor of microbial sulfate reduction as the processes that mediated pyrite framboid formation, in a semi-closed system. Barite formation occurred through the mixing of reducing and Ba-rich seep fluids with a 34S-enriched sulfate pool that resulted from microbial sulfate reduction in a semi-closed system. The chemical composition of aragonite cement, barite and pyrite suggest mineral precipitation from modified seawater. Taken together, our data suggest that mineralization at the studied seep sites is controlled by the mixing of seawater with minor amounts of hydrothermal, Peer Reviewed, Postprint (author's final draft)

El depósito de Sn-Zn-Pb-Ag de Japo-Santa Fe-Morococala se encuentra en la provincia metalogenética del cinturón Central Andino. La mineralización se encuentra encajada en una secuencia metasedimentaria paleozoica y rocas ígneas porfídicas del Oligoceno-Mioceno. Las menas se encuentran en vetas y diseminaciones. Se distinguen dos tipos de mineralización: (1) una mineralización temprana de Sn y (2) una mineralización tardía de Sn y Zn-Pb-Ag. La asociación mineral consiste principalmente en cuarzo, pirita, casiterita, sulfuros y sulfosales. La casiterita, hasta 0,25% en peso de In, constituye la mineralización más temprana. La galena y la esfalerita son los principales sulfuros. La esfalerita presenta 0,24% de In. Los minerales del grupo de la estannita están representados por estannoidita, kersterita y sulfuros del sistema Sn-Cu-ZnFe-S. Las sulfosales incluyen sakuraiita, potosiita, franckeita, freibergita, tetrahedrita, myargyrita, boulangerita, jamesonita, zinckenita, cylindrita y andorita. En este depósito, después de una etapa magmática epigenética, se produjo un largo evento greisen-hidrotermal con varios episodios de deposición de metales., Peer Reviewed, Postprint (published version)

The Santa Fe mining district is located in the Central Andean tin belt and contains several Sn-Zn-Pb-Ag deposits. From the economic point of view, the most important deposits of the district are Japo, Santa Fe and Morococala. Beyond the traditional metal commodities, Central Andean Tin Belt could become an exploration target for indium, owing to the potential of the ore-bearing paragenesis to contain high concentrations of this technology-critical element. Notwithstanding the foregoing, important features about genesis and fluids evolution have been poorly studied. This work presents a reinterpretation of the Santa Fe deposit as a greisen deposit based in fluid inclusions and isotopic data, as well as, an extensive and accurate fieldwork. In the Santa Fe district, the ore mineralization occurs as two main styles: (a) Sn-rich mineralization, represented by cassiterite-quartz veins, and (b) Zn-Pb-Ag mineralization, represented by sphalerite, galena and stannite group phases. The In contents in igneous rocks are between 1.5 and 2.5 ppm, whereas in the ore concentrate it attains up to 200 ppm. The 1000×In/Zn ratio ranges from 25 up to 4000. Exceptionally high In values were found in sakuraiite (2.03 wt.%). Sakuraiite in this deposit show evidences for a link between stannite-kësterite solution. Thus, there is an important relationship between stannite group and sulfosalts. Likewise, an important number of metal associations, including base, alloy, noble and critical metals, have been found in this ore deposit. There is a noteworthy exploration potential for these metals in the Santa Fe District and even in similar deposits also elsewhere in the Central Andean tin belt., El districte miner de Santa Fe està situat a la faixa estannífera de la serralada central andina, la qual conté importants dipòsits de Sn-Zn-Pb-Ag. Des del punt de vista econòmic, els dipòsits més importants d'aquest districte són els de Japo, Santa Fe i Morococala. Més enllà dels productes metàl·lics tradicionals, la faixa estannífera podria convertir-se en un potencial objectiu d'exploració degut als elements estratègics que conté, entre ells l'indi. No obstant això, el coneixement dels aspectes més destacats de l'evolució i la gènesi dels fluids mineralitzadors en aquesta zona és incipient. Per aquesta raó, aquest treball pretén aclarir i reinterpretar la història i evolució geològica del jaciment de Santa Fe, classificant-lo com un dipòsit tipus greisen a partir de les associacions minerals i el seu quimisme. Així com, en l'estudi geotermomètric i considerant les dades isotòpiques obtingudes i amb base en un treball exhaustiu i sistemàtic de camp. Les menes metàl·liques del jaciment es presenten en dos tipus principals: (a) mineralització rica en Sn, representada per les vetes de quars i cassiterita, i (b) mineralització de Zn-Pb-Ag, representada per esfalerita, galena i minerals del grup de l'estannita. La geoquímica del conjunt de roques ígnies encaixants també va ser analitzada. El contingut d'indi és d'entre 1,5 i 2,5 ppm, el concentrat arriba fins a 200 ppm i la relació 1000×In/Zn oscil·la entre 25 i 4000. Addicionalment, s'han trobat valors excepcionalment alts d'indi en cristalls de sakuraiita (2.03% en pes), mostrant l'evidència d'un vincle entre la solució d'estannita-kësterita, de la qual es pot inferir una relació genètica entre el grup de l'estannita i altres sulfosals en aquest dipòsit. El jaciment de Santa Fe també mostra un important nombre d'associacions metàl·liques, incloent-hi metalls base, aliatges, metalls nobles i metalls crítics. Hi ha un evident potencial d'exploració per aquests metalls al Districte de Santa Fe i fins i tot en dipòsits s, El distrito minero de Santa Fe se encuentra ubicado en la faja estannífera de la cordillera central andina, la cual contiene importantes depósitos de Sn-Zn-Pb-Ag. Desde el punto de vista económico, los depósitos más importantes de este distrito son los de Japo, Santa Fe y Morococala. Más allá de los productos metálicos tradicionales, la faja estannífera podría convertirse en un potencial blanco de exploración para elementos tecnológicamente estratégicos como el indio. No obstante lo anterior, el conocimiento de los aspectos más destacados respecto a la evolución y la génesis de los " uidos mineralizantes en este sector andino continúan siendo incipiente. Por ello, este trabajo pretende esclarecer y reinterpretar la historia y evolución geológica del yacimiento de Santa Fe, el cual en el presente trabajo se ha clasi! cado como un depósito tipo greisen con base fundamentalmente en el estudio de las asociaciones minerales y su química mineral; así como, en el estudio geotermométrico y considerando los datos isotópicos obtenidos, sin dejar de lado un exhaustivo y sistemático trabajo de campo. En el distrito de Santa Fe, las menas metálicas se presentan en dos estilos principales: (a) la mineralización rica en Sn, representada por las vetas de cuarzo y casiterita y (b) la mineralización de Zn-Pb-Ag, representada por esfalerita, galena y minerales del grupo de la estannita. La geoquímica de la suite de rocas encajantes también fue analizado. El contenido de In en rocas ígneas resulta ser de entre 1.5 y 2.5 ppm, mientras que en el concentrado de mineral alcanza hasta 200 ppm. La relación 1000 × In / Zn oscila entre 25 y 4000. Aunado a estos reslutados, valores excepcionalmente altos de In fueron encontrados en cristales de sakuraiita (2,03 % en peso). La sakuraiita en este depósito representa un vínculo entre la solución de stannite-kësterite, de lo cual puede inferirse una relación genética entre el grupo de la estannita y otras sulfosales en este depósito. Asimismo, el y, Postprint (published version)

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The Xilitla section of central Mexico (western margin of the proto-North Atlantic) is characterized by pelagic sediments enriched in marine organic matter. Using biostratigraphic and radiometric data, it was dated at the latest Cenomanian-earliest Turonian transition. We identified an interval coeval with the faunal turnover associated with the Oceanic Anoxic Event 2 (OAE 2), recording the Heterohelix shift and the, Peer Reviewed, Preprint

El Proyecto Geoparque Comarca Minera se encuentra ubicado en el estado de Hidalgo (México), y actualmente busca ser reconocido por la UNESCO al incorporarse a su Red Global de Geoparques. La red de geoparques a la fecha está conformado por un total de 120 territorios, en 33 países, ninguno de ellos en México. El proyecto Comarca Minera se encuentra actualmente en etapa de evaluación. El patrimonio de este territorio está encabezado por sus yacimientos argentíferos en vetas, que hicieron de esta región el principal productor de plata mundial durante cuatro siglos. Otro destacado elemento del patrimonio geológico lo constituyen los Prismas Basálticos de Huasca. Asimismo, su importancia histórica atrajo exploradores y científicos, como Alexander Von Humboldt, o Gerhard vom Rath (descubridor de la cristobalita y la tridimita). El posterior cese de la actividad minera dejó un legado importante en la arquitectura, la cultura popular e incluso la gastronomía. La denominación de geoparque es una estrategia de conservación basada en la valorización y el conocimiento del patrimonio. En este sentido, también se busca fomentar la investigación en temas prioritarios como los riesgos geológicos, el cambio climático y las geoenergías. De este modo, el proyecto implica un cambio de paradigmas del binomio conservación¿desarrollo, no sólo para Hidalgo, sino para todo México., Peer Reviewed, Postprint (published version)

The Santa Fe Mining District (SFD) is located in the Bolivian portion of the Central Andean Belt, which is an important tin province that hosts abundant world-class deposits, some of them with high indium content. In this work, we studied the mineralizations of Japo, Santa Fe and Morococala, in the SFD, in order to understand the mineralizing processes with focus in mineral chemistry and mineralogical assemblages. The SFD consists of a turbiditic Ordovician metasedimentary basement overlaid by a continuous sedimentary Silurian sequence represented by the Cacañiri, Llallagua and Uncia Fm. This sequence was folded and thrusted by an intense tectonic activity and is unconformably covered by the volcanic complex of the Morococala Fm., constituted by calc-alkaline lavas and tuffs of Miocene age (Grant et al., 1979). The ore mineralization is associated to felsic magmatism, represented by several generations of dykes and the San Pablo stock, of Oligocene-Miocene age (Grant et al., 1979). Ore mineralization occurs as veins and disseminations and consists of cassiterite, sulphides and sulfosalts. A wide shear zone and two fracture systems are developed: (1) N°40, dipping 60°W, with Sn-Zn, and (2) N°40, dipping 75°E, with Zn-Pb-Ag. Mineralogy was characterized by X-ray diffraction, scanning electron microscopy and electron probe micro-analyzer (EPMA). Mineral assemblages in the district are rather uniform but the relative contents among ore minerals vary from one deposit to another. Two main stages of mineralization are distinguished: (1) An early Sn mineralization represented by cassiterite; and (2) a late Sn and Zn-Pb-Ag mineralization, represented by sphalerite, galena, stannite group and sulfosalts. In Japo and Morococala cassiterite and sulphides as stannite, stannoidite, sakuraiite and kësterite predominate. EPMA analyses indicate that in these mines indium content ranges between 0.12 and 0.25 wt.% in cassiterite, reaches up to 0.9 wt.% in stannite, and attains the hig, Peer Reviewed, Postprint (published version)

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This is a post-peer-review, pre-copyedit version of an article published in Mineralium deposita. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00126-014-0556-x., The Chahmir zinc-lead deposit (1.5 Mt @ 6 % Zn + 2 % Pb) in Central Iran is one among several sedimentary-exhalative Zn-Pb deposits in the Early Cambrian Zarigan-Chahmir basin (e.g., Koushk, Darreh-Dehu, and Zarigan). The deposit is hosted by carbonaceous, fine-grained black siltstones, and shales interlayered with volcaniclastic sandstone beds. It corresponds to the upper part of the Early Cambrian volcano-sedimentary sequence (ECVSS), which was deposited on the Posht-e-Badam Block during back-arc rifting of the continental margin of Central Iran. Based on crosscutting relationships, mineralogy, and texture of sulfide mineralization, four different facies can be distinguished: stockwork (feeder zone), massive ore, bedded ore, and distal facies (exhalites with barite). Silicification, carbonatization, sericitization, and chloritization are the main wall-rock alteration styles; alteration intensity increases toward the proximal feeder zone. Fluid inclusion microthermometry was carried out on quartz associated with sulfides of the massive ore. Homogenization temperatures are in the range of 170-226 A degrees C, and salinity is around 9 wt% NaCl eq. The size distribution of pyrite framboids of the bedded ore facies suggests anoxic to locally suboxic event for the host basin. delta S-34((V-CDT)) values of pyrite, sphalerite, and galena range from +10.9 to +29.8 aEuro degrees. The highest delta S-34 values correspond to the bedded ore (+28.6 to +29.8 aEuro degrees), and the lowest to the massive ore (+10.9 to +14.7 aEuro degrees) and the feeder zone (+11.3 and +12.1 aEuro degrees). The overall range of delta S-34 is consistent with a sedimentary environment where sulfide sulfur was derived from two sources. One of them was corresponding to early ore-stage sulfides in bedded ore and distal facies, consistent with bacterial reduction from coeval seawater sulfate in a closed or semiclosed basin. However, the delta S-34 values of late ore-stage sulfides, observed mainly in m, Peer Reviewed, Postprint (author's final draft)

The Sn-Zn-Pb-Ag Japo-Santa Fe-Morococala ore deposit is located in the Central Andean Belt province. The ore mineralization is hosted in a Paleozoic metasedimentary sequence and porphyritic Oligocene-Miocene igneous rocks. Ore minerals occur in veins and disseminations. Two types of ore mineralization are distinghished: (1) An early Sn mineralization and (2) a late Sn and Zn-Pb-Ag mineralization. Mineral association consists mainly of quartz, pyrite, cassiterite, other sulfides and sulfosalts. Cassiterite, up to 0.25 wt% In, constitutes the earliest mineralization. Galena and sphalerite are the main sulphide minerals. Sphalerite shows up 0.24 wt% In. Stannite group is represented by stannoidite, kësterite, and sulfides of the Sn-Cu-Zn-Fe-S system. Sulfosalts include sakuraiite, potosiite, franckeite, freibergite, tetrahedrite, myargyrite, boulangerite, jamesonite, zinckenite, cylindrite and andorite. In this deposit, after an epigenetic magmatic stage, a long greisen-hydrothermal event took place with several episodes of metal deposition., Peer Reviewed, Postprint (published version)

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The Zarigan-Chahmir basin is placed to in the southern part of a crustal domain known as the Central Iranian microcontinent, at the northwestern margin of Gondwana. It hosts abundant mineral deposits, particularly of the iron oxide-apatite (IOA), Fe-Mn exhalative, and Zn-Pb sedimentary-exhalative (SEDEX) types. The evolution of this basin is governed by the Proto-Tethys oceanic crust subduction beneath the Central Iranian microcontinent and by the resulting continental arc and back-arc systems. This evolution followed two major stages of rifting: (I) Stage I or syn-rift phase, related to intra-basin extension, occurred first. This stage is indicated by coarse-grained detrital sedimentary rocks and bimodal volcanism (basis of the Early Cambrian Volcano-Sedimentary Sequence; ECVSS), which filled half-graben systems. During this stage, tuff-hosted stratiform, exhalative Fe-Mn deposits along with Kiruna-type IOA deposits formed. The former deposits (e.g., Narigan) are related to early submarine rhyolithic volcanism of the rift-phase sequence, whereas the later (e.g., Esfordi, Choghart, Chadormalu, Chahgaz) are connected to hydrothermal activity directly linked to the arc calk-alkaline magmatism. (II) Stage II or sag-phase, involveding the deposition of calcareous shales, siltstones and carbonates (upper part of the ECVSS). Sedimentation during this phase was controlled by basin subsidence and by the reactivation of the half-graben faults. SEDEX deposits are hosted within a carbonaceous, black siltstone unit of the sag-phase sequence, which was deposited during a period of rapid basin subsidence and under anoxic conditions. The location of synsedimentary faults and the prevalence of anoxic conditions were key factors controlling SEDEX mineralization processes in the basin. An elevated geothermal gradient caused by maximum syn-rift magmatism and sub-crustal lithospheric thinning, affecting primarily the center, western and southwestern basin, may have driven a basin-scale, Peer Reviewed, Postprint (published version)

The Acoculco geothermal system is hosted by a caldera complex located at the eastern portion of the Trans-Mexican Volcanic Belt. Surface manifestations are scarce and consist of low temperature, bubbling, acid–sulfate springs that are concentrated in two zones separated from each other by ~1750 m. In the northernmost one, there are conspicuous features suggesting recent, explosive, hydrothermal activity. Most of the rocks that crop out are tuffs and breccias that show pervasive hydrothermal alteration. Six SWIR-active minerals have been revealed by reflectance spectroscopy in the surface altered rocks: Opal, kaolinite, alunite, ammoniojarosite, buddingtonite and interstratified illite–smectite; they are indicative of alteration assemblages comparable to those reported in other geothermal systems and in epithermal deposits. Opal is the most widespread alteration mineral and occurs in association with tridimite and anatase. Kaolinite is also widely distributed but has a greater presence in the area with active surface manifestations, which, moreover, is the only area with alunite and ammoniojarosite occurrences. Buddingtonite occurs in the same zones as sulfates. As a complement to the alteration maps, we are proposing a simple method for mapping ammonium anomalies, based on total N analyses in altered rocks. Total N data show a discontinuous distribution within a wide range of variation (0.01–3.28 wt.%). All medium and high N values (>0.26 wt.%) plot in three clusters, two of which coincide with zones of gas emission. A deep circulating, active hydrothermal system cannot be ruled out in Acoculco although it may be confined to the deep caldera structure by an impermeable cap-rock of silicic and argillic alteration. In this scenario, hydrothermal fluids would reach the surface periodically, when explosive hydrothermal fracturing allowed it. The occurrence of hydrothermal explosion features and of acid–sulfate alteration supports this scenario. Therefore, further explor, Peer Reviewed, Postprint (published version)

The Mazatán barite deposits, Sonora, NW Mexico, represent an outstanding example of Paleozoic bedded barite, a poorly understood type of mineral deposit of major economic interest. The deposits of this type commonly occur hosted by shales and are characterized by the lack of base-metal sulfide mineralization, in contrast to classic sedimentary-exhalative (or SEDEX) deposits. A throughout study of the Mazatán barite deposits, based on petrography, fluid inclusions analyses and isotope geochemistry, confirmed the link between bedded barite and fossil hydrocarbon seeps, thereby leaving hydrothermal vent-related processes ruled out. Hence, modern cold seeps in continental margins would account for the geological setting and genetic aspects of this type of deposit. The largest barite bodies of Mazatán are hosted within an Upper Carboniferous flysch succession, which formed part of an accretionary wedge related to the subduction of the Rheic Ocean beneath Gondwana. As well, a few barite occurrences are hosted in Upper Devonian, pre-orogenic turbidites. A variety of mineralized structures is displayed by barite, including: septaria nodules, enterolitic structures, rosettes and debris-flow conglomerates. Barite is accompanied by chalcedony, pyrite (framboids) and berthierine. Gas-rich fluid inclusions in barite were analyzed by micro-Raman spectroscopy and methane was identified, suggesting the occurrence of light hydrocarbons in the environment within which barite precipitated. 13C-depleted carbonates (δ13C: − 24.3 to − 18.7‰) were found in the barite deposits; they likely formed through anaerobic oxidation of methane coupled to sulfate reduction. Besides, these carbonates yield negative δ18O values (− 11.9 to − 5.2‰) reflecting the isotopic composition of Devonian–Carboniferous seawater; alternatively, this 18O-depletion could reflect late diagenetic processes. Methane-derived carbonates occur at modern hydrocarbon seeps and have been reported from Mesozoic, Cenozoic and, Peer Reviewed, Postprint (updated version)

Santa Fe is a Sn-Zn-Pb-Ag ore deposit located in the Oruro district, Central Andean Tin Belt, Bolivia. Mineralization occurs in veins and disseminations. It is hosted in Silurian shales and greywackes. The sedimentary sequence is folded and unconformably covered by a volcanic complex of the Morococala Formation, mainly constituted by tuffs of Miocene age. A wide Nº40 shear zone and two systems of fracture are developed. A Nº40 fracture system, dipping 60ºW, which hosts Sn and Zn minerals, and other in the same direction but dipping 75ºE, which is related to Zn-Pb-Ag veins. The mineralization is associated to intrusive felsic magmatism. Although there are not intrusive rocks in Santa Fe, a dyke and the felsic San Pablo stock occur at a distance of about 10 km. In the present work we describe the geology and mineralogy of the Santa Fe deposit. X-ray diffraction, scanning electron microscopy and electron microprobe analyses were used to characterize the minerals. Veins are filled with quartz and an ore mineral assemblage of cassiterite, sulfides and sulfosalts. Cassiterite constitutes the earliest formed mineralization. Preliminar microprobe analyses indicate that it is nearly pure, with negligible contents in Nb and Ta. Rutile occurs as a late phase associated with a late generation of cassiterite. It forms thin neddle-like crystals. In addition, Sn is also present in sulfides as stannite, stannoidite and kësterite. Other sulfides are pyrrhotite, pyrite, arsenopyrite, galena, sphalerite, marchasite and argentite. Bismuthinite and berndite are found nin trace amounts. Sulfosalts include tetrahedrite, myarhyrite, boulangerite, jamesonite, franckeite, zinckenite, cilindrite and andorite. Associated with the mineralization, several phosphate minerals are found filling cavities and small fractures. The most abundant are monacite (Ce,La,Nd,Th)PO4 and plumbogummite (PbAl3(PO4)2(OH)5•(H2O)). Crandallite CaAl3(PO4)2(OH)5•(H2O) and vivianite (Fe3+(PO4)2•8(H2O)) also occur in mi, Peer Reviewed, Postprint (published version)

En el área de Huizachal Tamaulipas, el análisis de cuarzo mostro salinidades en el rengo de 18 a 28 % Eq. peso CaCl2 y temperaturas de homogeneización (Th) de 160º a 215 °. Para el cobre estratiforme del área de Cuatro Ciénegas se obtuvo un rango de salinidad de 26.3 a 38.57% de Eq. en peso CaCl2 para el cuarzo, y de 26.3 a 26.8 % Eq. peso CaC2 para la calcita; las temperaturas de homogeneización (Th) en el cuarzo es de 128º a 165 °C y para la calcita es de 98º a 115 °C. En el área de Las Vigas Chih., se analizaron muestras en la mena de cobre así como en troncos mineralizados con cobre: En la mena se obtuvo un rango de salinidad de 19.5 a 23.1% de Eq. en peso CaCl2 para el cuarzo en los fluidos subsaturados de la salmuera cálcica, los fluidos saturados del tipo S+L+V presentaron salinidades del orden de 29 a 40 % peso CaCl2 , las temperaturas de homogeneización variaron de Th = 150º a 180 °C; Un comportamiento semejante presentaron las inclusiones fluidas analizadas en la mineralización de troncos de madera reemplazados por cobre y ganga de cuarzo, donde se determino una salinidad de 15 a 33% peso CaCl2 con temperaturas de homogeneización de Th =146° a 214 °C. Nuestros datos son compatibles con un modelo genético relacionado a los primeros pulsos de la Orogenia Laramídica Mexicana, donde los fluidos cálcicos caliente mineralizantés cargados con cobre de la cuenca, migran hacia los bordes de las plataformas depositándose en horizonte permeables muy posiblemente en la interface de acuíferos colgados pre-existentes donde la mezcla y enfriamiento provocan la precipitación del cobre: De aquí su carácter estrato-ligado, Postprint (published version)

Los residuos generados por las actividades mineras en Bolivia representan graves problemas de contaminación ambiental. En las proximidades de las minas de estaño de Llallagua, en el Departamento de Potosí, existen escombreras y colas de grandes dimensiones. Para el presente trabajo se ha estudiado la utilización de estos residuos como materias primas para la fabricación de vidrio. Con ello se pretende contribuir a la remediación ambiental, ofreciendo con la vitrificación una alternativa para la estabilización de residuos potencialmente peligrosos. Además, la comercialización del producto obtenido podría proporcionar un beneficio económico adicional de la actividad minera. En este estudio se han utilizado tres muestras de residuos con granulometría entre arena y limo. Su composición química, determinada por fluorescencia de rayos X, es granítica, con un elevado contenido en metales pesados. Sobre la base de su composición se han formulado vidrios de sílice mediante la adición CaCO3 y Na2CO3. El ciclo térmico se ha determinado a partir del análisis térmico diferencial (ATD). Los valores de la temperatura de transición de los vidrios, Tg, del vidrio obtenido oscilan entre 626º y 709 ºC. Por último, se han realizado las pruebas de lixiviación, las cuales corroboran la idoneidad de los vidrios obtenidos para retener los metales pesados., Peer Reviewed, Postprint (published version)

En el área de Huizachal Tamaulipas, el análisis de cuarzo mostro salinidades en el rengo de 18 a 28 % Eq. peso CaCl2 y Th de 160º a 215 °. Para el cobre estratiforme del área de Cuatro Ciénegas se obtuvo un rango de salinidad de 26.3 a 38.57% de Eq. en peso CaCl2 para el cuarzo, y de 26.3 a 26.8 % Eq. peso CaCl2 para la calcita; las temperaturas de homogeneización (Th) en el cuarzo es de 128º a 165 °C y para la calcita es de 98º a 115 °C. En el área de Las Vigas Chih., se analizaron muestras en la mena de cobre así como en troncos mineralizados con cobre: En la mena se obtuvo un rango de salinidad de 19.5 a 23.1% de Eq. en peso CaCl2 para el cuarzo en los fluidos subsaturados de la salmuera cálcica, los fluidos saturados del tipo S+L+V presentaron salinidades del orden de 29 a 40 % peso CaCl2, las temperaturas de homogeneización variaron de Th = 150º a 180 °C; Un comportamiento semejante presentaron las inclusiones fluidas analizadas en la mineralización de troncos de madera reemplazados por cobre y ganga de cuarzo, donde se determino una salinidad de 15 a 33% peso CaCl2 con temperaturas de homogeneización de Th =146° a 214 °C. Nuestros datos son compatibles con un modelo genético relacionado a los primeros pulsos de la Orogenia Laramídica Mexicana, donde los fluidos cálcicos caliente mineralizantés cargados con cobre de la cuenca, migran hacia los bordes de las plataformas depositándose en horizonte permeables muy posiblemente en la interfaz de acuíferos colgados pre-existentes donde la mezcla y enfriamiento provocan la precipitación del cobre: De aquí su carácter estrato-ligado., Postprint (published version)

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En la cuenca de Sabinas la Orogenia Larámide detonó el flujo de fluidos asociado a las zonas más profundas de la cuenca, iniciándose así la acumulación de yacimientos estratoligados en el Noreste de México, los cuales se acumularon preferencialmente en los bordes de las plataformas que limitan dicha cuenca. Las condiciones de temperatura, composición y presión de los fluidos tran sportadores y mineralizantes han quedado registradas en minerales neoformados como la celestina, barita, fluorita, esfalerita, barita, dolomita y calcita. Por medio de la microtermometría de inclusiones fluidas las temperaturas de fusión final (Tff) en los distintos yacimientos estratoligados de la cuenca de Sabinas indican salinidades bajas a medias y temperaturas de homogeneización (Th) bajas a moderadas. Así las inclusiones fluidas relacionadas con yacimientos estratiformes de cobre se caracterizan por contener un fluido cálcico, presentando una Th = 149° a 152°C y una salinidad promedio de 22 wt.% CaCl 2 . Los mantos de plomo+zinc presentan salinidades entre 7 y 22 wt.% NaCl equiv y Th de 75°C a 225°C; los mantos de barita presentan una salmuera clorurado sódica y cálcica con predominio de esta última en un rango de 1 a 2 wt.% NaCl equiv y de 8 a 24 wt.% CaCl 2 , en un rango de Th entre 50° y 155°C; los cuerpos de celestina presentan salinidades de 1 a 12 wt.% NaCl equiv y Th de 70° a 165°C; los mantos y brechas de fluorita presentan salinidades de 6 a 14 wt.% NaCl equiv y Th de 50° a 159°C, y presentan inclusiones fluidas con hidrocarburos. La relación Cl/Br de las salmueras atrapadas en las inclusiones fluidas muestra una tendencia compatible con la evaporación del agua de mar y un proceso de dilución , muy probablemente debido a la interacción con aguas meteóricas. Por otro lado, las relaciones Cl/Br vs. Na/Cl y Cl/Br vs. K/Cl muestran una fuerte interacción agua/roca. Se concluye que los fluidos con alta salinidad y temperat uras superiores a los 210°C y presurizados (> 400 bars) re, Peer Reviewed, Postprint (published version)

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The submarine hydrothermal vents located in the vicinity of Punta Mita contain abundant deposition of calcite, pyrite. Also present are barite, carbonate hydroxyl-apatite, cinnabar and T1-sulfide.Textures indicate direct deposition for calcite and pyrite; however, pyrite also replaces magnetite in the host rock. Thermal water was filtered and microscopic analysis of the particles fiom the filters shows that the shape of the crystals varies euhedral crystals of pyrite to globular aggregates that may be interpreted as a mixture of chemical and biogenic precipitation. Isotopic signature of sulfur in pyrite and carbón in calcite indicates that biogenic deposition is an important phenomenon in this hydrothermal system, Peer Reviewed, Postprint (published version)