• Rift-related geothermal activity and epithermal gold veins

    Rift-related geothermal activity and epithermal gold veins Jeffrey W. Hedenquist University of Ottawa • NZ rift-related geothermal activity and characteristics • Features of rift-related epithermal Au veins • Controls on vein characteristics • Potential for epithermal Au veins in …

  • An Overview of Epithermal Gold Deposits | Investing News ...

    Epithermal deposits are a type of lode deposit.They contain economic concentrations of gold, silver and in some cases base metals such as copper, lead and zinc. Like other lode deposits, the ...

  • Epithermal Gold Deposits Characteristics

    A fascinating group and characteristic of Epithermal gold deposits is that you can virtually see them forming today, simply by visiting hot springs. Like those with Yellowstone in Wyoming or Rotorua in New Zealand. This photo is Pamukkale, low sulfidation hot springs in Turkey, with a beautiful white centre terraces. If you like hot springs, you'll love epithermal.

  • Characteristics of Mineral Deposits - Encyclopedia of Life ...

    UNESCO – EOLSS SAMPLE CHAPTERS GEOLOGY – Vol. IV – Characteristics of Mineral Deposits - Maria Boni ©Encyclopedia of Life Support Systems (EOLSS) and seams in the rocks. Then he must be thoroughly familiar with the many and varied species of earths, …

  • Chapter 7 Exploration for Epithermal Gold Deposits

    to action. Insight into how the characteristics of an ore style may be affected by various geologic settings can be bol-stered by an understanding of how the processes of ore for-mation are manifested as hydrothermal products such as patterns of alteration and ore minerals. In the case of exploration for epithermal gold deposits, this understand-

  • Gold Deposits - EOLSS

    1. orogenic gold deposits 2. Carlin-type gold deposits 3. epithermal deposits 4. porphyry copper-gold deposits 5. iron oxide copper-gold deposits 6. gold-rich massive sulfide deposits The seventh type—the Witwatersrand pebble-conglomerate type— may be an ancient alluvial placer, but which others include in the orogenic gold type. In highly ...

  • CHARACTERISTICS OF HIGH-SULFIDATION EPITHERMAL …

    CHARACTERISTICS OF HIGH-SULFIDATION EPITHERMAL DEPOSITS, AND THEIR RELATION TO MAGMATIC FLUID Antonio Arribas Jr. Mineral Resources Department, Geological Survey of Japan, 1-1-3 Higashi, Tsukuba 305, Japan INTRODUCTION A consequence of the increased exploration for gold deposits during the late 1970s and early

  • Hydrothermal mineral deposit - Wikipedia

    Hydrothermal mineral deposits are accumulations of valuable minerals which formed from hot waters circulating in Earth's crust through fractures. They eventually create rich-metallic fluids concentrated in a selected volume of rock, which become supersaturated and then precipitate ore minerals.In some occurrences, minerals can be extracted at a profit by mining.

  • A Prospector's Guide to Alteration and Epithermal Gold ...

    style, gold-rich VMS deposit. The style of mineralization at Ridgeway and Haile mines is more unclear, and both syn-metamorphic and metamorphosed epithermal origins have been argued for these deposits. To date, classic low-sulphidation-style epithermal systems have only been identified within Avalonian rocks of Newfoundland.

  • Epithermal Gold Deposits | Geology for Investors

    Epithermal gold deposits are among the richest gold deposits in the world with some bonanza grade ore shoots containing more than 1000 g/t gold, or in other words, a kilogram of gold for every tonne of rock mined. Unfortunately, the tonnage of ore in epithermal veins is typically small compared with other types of lower grade gold deposits.

  • Characteristics of high-sulfidation epithermal deposits ...

    In Magmas, Fluids, and Ore Deposits, Ed.: J.FM. Thompson, Mineralogical Association of Canada Short Course Vol. 23 (1995) Chapter 19 CHARACTERISTICS OF HIGH-SULFIDATION EPITHERMAL DEPOSITS, AND THEIR RELATION TO MAGMATIC FLUID Antonio Arribas Jr. Mineral Resources Department, Geological Survey ofJapan, 1-1-3 Higashi, Tsukuba 305, Japan INTRODUCTION …

  • Descriptive models for epithermal gold-silver deposits ...

    Epithermal gold-silver deposits are vein, stockwork, disseminated, and replacement deposits that are mined primarily for their gold and silver contents; some deposits also contain substantial resources of lead, zinc, copper, and (or) mercury. These deposits form in the uppermost parts of the crust, at depths less than about 1,500 meters below the water table, and at temperatures below about ...

  • Mineral Resources Program - Publications - usgs.gov

    Miocene calc-alkaline volcanic rocks, part of the southern segment of the ancestral Cascades magmatic arc, are spatially, temporally, and likely genetically associated with precious metal epithermal deposits in the Tonopah, Divide, and Goldfield Districts of west-central Nevada. In the Tonopah mining district, volcanic rocks include the Mizpah...

  • Characteristics and Genesis of Epithermal Gold Deposits ...

    This paper summarizes the characteristics of epithermal gold deposits and discusses potential ore deposition mechanisms. Epithermal deposits mostly form at shallow crustal levels (<1 km) in subaerial volcanic settings. There are two classes of epithermal deposits which can be discriminated in terms of their geologic environments, alteration ...

  • Geochemical characteristics of igneous rocks associated ...

    Newly synthesized data indicate that the geochemistry of igneous rocks associated with epithermal mineral deposits varies extensively and continuously from subalkaline basaltic to rhyolitic compositions. Trace element and isotopic data for these rocks are consistent with subduction-related magmatism and suggest that the primary source magmas were generated by partial melting of the mantle ...

  • Miocene and Early Pliocene Epithermal Gold-Silver …

    Characteristics, Distribution, and Relationship to Magmatism DAVID A. JOHN† U.S. Geological Survey, Mail Stop 901, 345 Middlefield Road, Menlo Park, California 94025 Abstract Numerous important Miocene and early Pliocene epithermal Au-Ag deposits are present in the northern Great Basin.

  • EPITHERMAL GOLD DEPOSITS: STYLES, CHARACTERISTICS …

    Published in SEG Newsletter, 1995, No. 23, pp. 1, 9-13 EPITHERMAL GOLD DEPOSITS: STYLES, CHARACTERISTICS AND EXPLORATION Noel C. White1 and Jeffrey W. …

  • Characteristics and controls of the largest porphyry ...

    These large porphyry‐type deposits conform to a single overall model, whereas the large epithermal gold deposits are varied in both genetic type and mineralisation style. Most regional and local characteristics of the largest porphyry and epithermal deposits fail to explain convincingly their extremely high gold contents.

  • Ore deposits: Epithermal Deposits [Part 5] - YouTube

    Nov 02, 2014· Ore deposit is a natural concentration of one or more minerals within the host rock. 🔴 Subscribe: https://bit.ly/2xcAZYW About World Earthquakes: World Earthquakes is a non-profit, non ...

  • Mining Part One Flashcards | Quizlet

    Characteristics of epithermal. 1500 m deep volcanic are 50 - 200 degrees C Gold and Silver. Characteristics of Mesothermal. 5 - 10 km deep Mountain Building 200 - 300 degrees C ... heavy minerals become concentrated and form deposits. Ore is concentrated by running water. Place Deposit. formed by descenting waters as mineral or ore deposit.

  • Epithermal Gold Deposits Part 1! - USGS

    Epithermal Gold Deposits Part II Geology and Gold Deposits of the Oatman District, Northwestern Arizona By Ed DeWitt, Jon P. Thorson,1 and Robert C. Smith2 Abstract Mines in the Oatman mineralized district, near Oatman in northwestern Arizona, have produced more than 1.98 million ounces of gold from mid-Tertiary, epithermal, silver-

  • Epithermal Gold Deposits-Paf! I - USGS

    Epithermal Gold Deposits-Part I The Goldfield Gold District, Esmeralda and Nye Counties, Nevada By Roger P. Ashley Abstract The Goldfield district is an epithermal prec1ous metal depos1t of the quartz-alunrte type. Gold ore bod1es are assoc1ated spatially and temporally wrth a calc-alkalic vol­

  • Epithermal Gold Deposits : their characteristics & modeling

    Ore deposits: Classification vs Modeling Each ore deposit is unique like a person's finger print This uniqueness arises out of : ¾fundamental differences in processes and environments ¾local, site-specific geologic variations And produces an extremely large variation in characteristics ¾If we group the deposits according to their characteristics, we get a

  • Nanoparticles in Epithermal Ores - mdpi.com

    2.1. Bonanza Epithermal Ore Characteristics The term "bonanza" implies a relatively rich ore of gold silver, and it has been proposed that metal nanoparticle formation and aggregation are important processes in producing such high-grade epithermal ores [12–14]. Epithermal deposits, which typically form at temperatures of <350 C in

  • Epithermal gold deposits in volcanic terranes | SpringerLink

    Epithermal mineral deposits are the products of large-scale hydro thermal convective systems driven by magmatic heat in the upper 5–10 km of the Earth's crust. The choice of such a broad definition...

  • Low Sulphidation Epithermal Gold Deposits

    Although they are a product of the same igneous system, low sulfidation epithermals gold deposits are very different from high sulfidation. In low sulfidation the main control for Gold deposition, is fluid boiling – caused by a drop in the confining pressures the fluid approaches the surface. This below is an image of a simple low sulfidation vein system, with all its components preserved ...

  • Epithermal deposits: geological characteristics and ...

    Epithermal deposits: geological characteristics and genetic processes for exploration and discovery One day short course, Sunday 17 November Presenter Stuart Simmons at [email protected] Short course description Epithermal deposits are diverse …

  • ORE DEPOSIT TYPES AND THEIR PRIMARY EXPRESSIONS K.G ...

    Deposit form and geometry can vary greatly but, in many cases, these features also reflect the nature of the ore-forming process. Thus, hydrothermal deposits show forms related to the geometry of the fluid channelways (e.g., veins or stockworks along fractures). Syngenetic deposits are commonly stratabound (i.e., confined to a particular

  • Exploration of Low Sulfidation Epithermal Vein Systems

    Epithermal Vein Systems L ow Sulfidation Epithermal Vein Deposits ("LSEVD") share many common characteristics whose recognition and interpretation allow explorationists to determine the magnitude of a given system and general location within the system, and thereby focus exploration. A brief

  • Epithermal deposit | geology | Britannica.com

    Other articles where Epithermal deposit is discussed: mineral deposit: Veins: …are commonly referred to as epithermal, a term retained from an old system of classifying hydrothermal deposits based on the presumed temperature and depth of deposition. Epithermal veins tend not to have great vertical continuity, but many are exceedingly rich and deserving of the term bonanza.