موضوع تخصصی
فلوتاسیون کالکوپیریت و کانه های سولفیدی
معرفی و چکیده
توضیحات منبع
خلاصه فارسی
این کتاب در فیلد «زمینشناسی، اکتشاف و معدنکاری مس» و زیرموضوع «فلوتاسیون کالکوپیریت و کانههای سولفیدی» قرار میگیرد. محورهای قابل تشخیص از عنوان و متادیتای Lens عبارتاند از: کالکوپیریت، کانسار رسوبمیزبان، کانسار استراتیفرم، ژئوشیمی. این منبع مستقیماً بر یکی از اجزای زنجیره ارزش مس تمرکز دارد. برای شناخت کانسار، هدفگذاری اکتشافی، طراحی معدن و بررسی عملیات استخراج کاربرد دارد. این متن یک خلاصه موضوعی فارسی بر پایه متادیتای موجود است؛ چکیده انگلیسی، در صورت وجود، در ستون جداگانه حفظ شده است.
چکیده انگلیسی
In the Paradox basin, epigenetic, post-lithification deposition of copper sulfides in stratiform sediment-hosted deposits is the result of two sequential episodes of basinal fluid expulsion. The earlier fluid was a sulfur-bearing, reducing, aqueous fluid that bleached red sandstones as hematite was reduced to pyrite (Thorson, 2004; MacIntyre et al., 2004, 2005). This fluid rose buoyantly through the section along marginal breccia zones adjacent to salt diapirs, or along faults, and flowed laterally in permeable strata. Regional geology and burial history analyses suggest a Late Jurassic age for the early fluid event as organic-rich black shale in the Paradox Formation evaporites entered the oil window.; ; The second episode of fluid expulsion involved oxidized warm saline brines carrying copper, silver, and other base metals. At Lisbon Valley and Cashin mine, minerals deposited by the second fluid are zoned from hematite ± native copper, through chalcocite, bornite, and chalcopyrite zones, to peripheral pyrite + lead and zinc. Copper sulfides are disseminated, partially or completely filling intergranular spaces in sandstone bleached during alteration by the first fluid. Gangue minerals in feeder fault structures are saddle dolomite and barite. Homogenization temperatures from fluid inclusions in these gangue minerals are between 70° and 110°C; salinities are variable but as high as 21% NaCl equiv (Morrison and Parry, 1986; Breit and Meunier, 1990; Gray et al., 1996). Fluid inclusions from bleached Jurassic sandstones and from the Cashin fault contain hydrocarbon droplets from Pennsylvanian Paradox blac shale source rocks. Paleomagnetic data and burial history analyses suggest a Late Cretaceous or early Tertiary age for the second episode of fluid expulsion as Cutler Formation arkosic red beds subsided into the oil window. The copper deposit at Lisbon Valley and Cashin mines are the result of both fluid expulsion episodes. The earlier fluid prepared otherwise unfavorable host rocks by reducing hematite to pyrite and depositing hydrocarbons. The second fluid deposited copper as sulfides that replaced pyrite, calcite, bituminous hydrocarbon, and coaly plant material.; ; The Paradox basin is a Pennsylvanian halfgraben rift that initially received several thousand feet of evaporites designated as the Paradox Formation or the Paradox member of the Hermosa Formation (Fig. [1][1]). Many authors define the Paradox basin by the zero thickness edge of the evaporite facies, but a significant area of Pennsylvanian shelf carbonates was deposited in less restricted conditions on the west, south, and east sides of the basin (Fig. [2][1], this paper; Hite, 1970). The evaporites occur as cyclical deposits of silty dolomite, black shale, anhydrite, and halite; a few cycles in the most restricted areas contain potassium salts (Hite, 1961; Hite and Buckner, 1981).; ; [1]: /gswbk/9781934969908/9781934969908/SEC1.atom
