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Hrinchenko O.V. THEORY of ORE FORMATION Educational Textbook

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Hrinchenko O.V. THEORY of ORE FORMATION Educational Textbook ɍȾɄ TARAS SHEVCHENKO NATIONAL UNIVERSITY OF KYIV Ɋɟɰɟɧɡɟɧɬɢ: Institute of Geology Department: Geology of mineral deposits ȾɭɛɢɧɚɈȼ, Ⱦɨɤɬɨɪɧɚɭɤ, ɞɨɰɟɧɬ; Ʉɢʀɜɫɶɤɢɣɧɚɰɿɨɧɚɥɶɧɢɣɭɧɿɜɟɪɫɢɬɟɬɿɦɟɧɿ Ɍɚɪɚɫɚɒɟɜɱɟɧɤɚ Ȼɨɧɞɚɪɟɧɤɨɋ0, Ʉɚɧɞɢɞɚɬ ɝɟɨɥɨɝɿɱɧɢɯ ɧɚɭɤ, ɫɬɚɪɲɢɣ ɧɚɭɤɨɜɢɣ ɫɩɿɜɪɨɛɿɬ- ɧɢɤ; ȱɧɫɬɢɬɭɬɝɟɨɯɿɦɿʀ, ɦɿɧɟɪɚɥɨɝɿʀɬɚɪɭɞɨɭɬɜɨɪɟɧɧɹ, ɇȺɇɍɤɪɚʀɧɢ. Hrinchenko O.V. ȽɪɿɧɱɟɧɤɨO.ȼ. ɌȿɈɊȱəɊɍȾɈɍɌȼɈɊȿɇɇə ɇɚɜɱɚɥɶɧɢɣɩɨɫɿɛɧɢɤ±Ʉȿɥɟɤɬɪɨɧɧɟɜɢɞɚɧɧɹ±ɫ Ɋɨɡɥɹɞɚɸɬɶɫɹ ɩɨɧɹɬɬɹ ɩɪɨ ɪɭɞɨɝɟɧɟɡ ɬɚ ɨɫɨɛɥɢɜɨɫɬɿ ɭɬɜɨɪɟɧɧɹ ɝɨɥɨɜɧɢɯ ɬɢɩɿɜ ɪɨɞɨɜɢɳ ɤɨɪɢɫɧɢɯ ɤɨɩɚɥɢɧ ɇɚɜɟɞɟɧɿ ɞɚɧɧɿ ɩɪɨ ɫɭɱɚɫɧɿ ɤɥɚɫɢɮɿɤɚɰɿʀ ɪɨɞɨɜɢɳɤɨɪɢɫɧɢɯ ɤɨɩɚɥɢɧ ɡɨɩɢɫɨɦɝɨɥɨɜɧɢɯɤɪɢɬɟɪɿʀɜɪɨɡɩɨɞɿɥɭɪɨɞɨɜɢɳ THEORY OF ORE FORMATION ɧɚɤɥɚɫɢ– ɫɬɪɭɤɬɭɪɧɢɣɤɨɧɬɪɨɥɶɦɨɪɮɨɥɨɝɿɹ ɪɭɞɧɢɯɩɨɤɥɚɞɿɜɫɩɿɜɜɿɞɧɨɲɟɧ- ɧɹ ɡɜɦɿɫɧɢɦɢɩɨɪɨɞɚɦɢɬɢɩɢ ɦɿɧɟɪɚɥɿɡɚɰɿʀɝɟɧɟɬɢɱɧɿ ɱɢɧɧɢɤɢ ɬɚɨɫɨɛɥɢɜɨ- ɫɬɿ ɩɪɨɹɜɭɪɭɞɨɮɨɪɦɭɜɚɥɶɧɢɯɩɪɨɰɟɫɿɜ Educational textbook ȼ ɪɨɡɞɿɥɚɯ ɧɚɜɱɚɥɶɧɨɝɨ ɩɨɫɿɛɧɢɤɚ ɨɯɚɪɚɤɬɟɪɢɡɨɜɚɧɿ ɝɨɥɨɜɧɿ ɝɟɨɥɨɝɿɱɧɿ ɩɪɨɰɟɫɢ ɳɨ ɫɩɪɢɱɢɧɹɸɬɶ ɭɬɜɨɪɟɧɧɹ ɪɨɞɨɜɢɳ ɤɨɪɢɫɧɢɯ ɤɨɩɚɥɢɧ ɦɚɝɦɚɬɨɝɟɧɧɨɝɨɝɿɞɪɨɬɟɪɦɚɥɶɧɨɝɨ ɩɨɫɬɦɚɝɦɚɬɢɱɧɨɝɨ) ɬɚɨɫɚɞɨɜɨɝɨɝɟɧɟɡɢɫɭ. ɇɚɞɚɸɬɶɫɹ ɜɿɞɨɦɨɫɬɿ ɩɪɨ ɝɨɥɨɜɧɿ ɮɚɤɬɨɪɢ ɦɚɝɦɚɬɨɝɟɧɧɨɝɨ ɤɪɢɫɬɚɥɿɡɚɰɿɣɧɚ ɞɢɮɟɪɟɧɰɿɚɰɿɹɥɿɤɜɚɰɿɹɮɿɥɶɬɪ-ɩɪɟɫɢɧɝ , ɝɿɞɪɨɬɟɪɦɚɥɶɧɨɝɨ ɞɠɟɪɟɥɚ ɜɨɞɧɢɯ ɮɥɸʀɞɿɜ ɪɨɡɱɢɧɟɧɧɹ ɬɚ ɩɟɪɟɧɨɫ ɪɭɞɧɢɯ ɤɨɦɩɨɧɟɧɬɿɜ ɭ ɜɨɞɧɢɯ ɮɥɸʀɞɚɯ ɪɭɞɨɜɿɞɤɥɚɞɚɧɧɹ , ɩɪɢɩɨɜɟɪɯɧɟɜɨɝɨ ɡɚɥɢɲɤɨɜɚ ɤɨɧɰɟɧɬɪɚɰɿɹ, ɩɪɢɩɨɜɟɪɯɧɟ- ɜɟɜɬɨɪɢɧɧɟ ɡɛɚɝɚɱɟɧɧɹ ɬɚ ɨɫɚɞɨɜɨɝɨ ɤɥɚɫɬɨɝɟɧɧɚ, ɯɟɦɨɝɟɧɧɚ ɬɚ ɛɿɨɝɟɧɧɚ ɫɟɞɢɦɟɧɬɚɰɿɹ ɪɭɞɨɝɟɧɟɡɭ. ɇɚɞɚɽɬɶɫɹɤɥɚɫɢɮɿɤɚɰɿɹɪɨɞɨɜɢɳ ɤɨɪɢɫɧɢɯɤɨɩɚɥɢɧ ɡɜɢɡɧɚɱɟɧɧɹɦ ɬɚɤɨ- ɪɨɬɤɢɦ ɨɩɢɫɨɦ ɝɨɥɨɜɧɢɯ ʀɯ ɬɢɩɿɜ Ʉɨɪɨɬɤɨ ɨɯɚɪɚɤɬɟɪɢɡɨɜɚɧɿ ɟɤɨɧɨɦɿɱɧɿ ɚɫɩɟɤɬɢɤɨɪɢɫɧɢɯɤɨɩɚɥɢɧɬɚɡɚɤɨɧɨɦɿɪɧɨɫɬɿɩɨɲɢɪɟɧɧɹʀɯɭɩɪɨɫɬɨɪɿɬɚɱɚɫɿ Ⱦɥɹɫɬɭɞɟɧɬɿɜɹɤɿɧɚɜɱɚɸɬɶɫɹɧɚɞɪɭɝɨɦɭɿɬɪɟɬɶɨɦɭɪɿɜɧɹɯɜɢɳɨʀɨɫɜɿɬɢɡɚ ɩɪɨɝɪɚɦɚɦɢɫɩɟɰɿɚɥɶɧɨɫɬɟɣɇɚɭɤɢɩɪɨɁɟɦɥɸɚɬɚɤɨɠɮɚɯɿɜɰɿɜ ɿɜɢɤɥɚɞɚɱɿɜ Ɋɟɤɨɦɟɧɞɨɜɚɧɚɜɱɟɧɨɸɪɚɞɨɸɇɇȱ©ȱɧɫɬɢɬɭɬɝɟɨɥɨɝɿʀª ɄɢʀɜɫɶɤɨɝɨɧɚɰɿɨɧɚɥɶɧɨɝɨɭɧɿɜɟɪɫɢɬɟɬɭɿɦɟɧɿɌɚɪɚɫɚɒɟɜɱɟɧɤɚ ɜɹɤɨɫɬɿɩɨɫɿɛɧɢɤɚɡɞɢɫɰɢɩɥɿɧɢ©Theory of ore formation» ɉɪɨɬɨɤɨɥʋ 10 ɜɿɞ12.03ɪ Ⱥɜɬɨɪ: Kyiv – 2018 Ƚɪɿɧɱɟɧɤɨ 2ȼ, ɤɚɧɞɢɞɚɬ ɝɟɨɥɨɝɨ-ɦɿɧɟɪɚɥɨɝɿɱɧɢɯ ɧɚɭɤ, ɞɨɰɟɧɬ ɤɚɮɟɞɪɢ ɝɟɨɥɨɝɿʀɪɨɞɨɜɢɳɤɨɪɢɫɧɢɯɤɨɩɚɥɢɧ TABLE OF CONTENTS (C) Sedimentary-hydrothermal: Introduction................................................................................................................... 6HGLPHQWDU\([KDODWLYH 6('(; GHSRVLWV 0LVVLVVLSSL9DOOH\7\SH 097 GHSRVLWV Part 1. Formation and interpretation of mineral deposits 6WUDWLIRUP6HGLPHQWKRVWHG&RSSHU 66& GHSRVLWV 1.1 Mineral deposit classification 5HODWLRQWRKRVWURFNV Part 4. Surficial and sedimentary ore formation *HRJUDSKLFORFDOL]DWLRQ 4.1 Surficial and sedimentary ore-forming processes 2FFXUUHQFHGHSWK Ⱥ) Weathering: 6WUXFWXUDOFRQWURO 5HVLGXDOFRQFHQWUDWLRQ 0LQHUDOL]DWLRQVW\OH 6XSHUJHQHHQULFKPHQW 0RUSKRORJ\ (B) Sedimentation: *HQHWLFIHDWXUHVDQGRUHIRUPLQJSURFHVVHV ɋODVWLFVHGLPHQWDWLRQ 1.2. Nature of minerals &KHPLFDOSUHFLSLWDWLRQ &ODVVLILFDWLRQRIRUHPLQHUDOV (C) Fossil fuel formation................................................................................................. 0LQHUDOJUDLQVL]H 4.2 Surficial type deposits 1.3. Mineral economics %DX[LWHV 2UHJUDGHDQGWRQQDJH 1LODWHULWHV 0LQHUDOUHVRXUFHVDQGRUHUHVHUYHV 6XSHUJHQHFRSSHUGHSRVLWV 1.4. Distribution of mineral deposits 4.3 Sedimentary type deposits 0LQHUDOGHSRVLWVDQGSODWHWHFWRQLFV 3ODFHUGHSRVLWV ,URQVWRQHVDQG%DQGHG,URQ)RUPDWLRQV Part 2. Magmatic ore formation 0DQJDQHVHGHSRVLWV 3KRVSKRULWHV 2.1. Magma types and metallogeny............................................................................... (YDSRULWHVDQG/LEULQHV 2.2. Magmatic ore-forming processes 4.4 Fossil fuels )UDFWLRQDOFU\VWDOOL]DWLRQ 2LODQGJDV /LTXLGLPPLVFLELOLW\ 3HDWDQGFRDO )LOWHUSUHVVLQJ 2.3 Magmatic type deposits References and recommended literature ....................................................... &KURPLWHGHSRVLWV 1LFNHO FRSSHU VXOILGHGHSRVLWV 3ODWLQXP*URXS(OHPHQW 3*( GHSRVLWV 'LDPRQGGHSRVLWV &DUERQDWLWHDVVRFLDWHGGHSRVLWV 3HJPDWLWHGHSRVLWV Part 3. Hydrothermal ore formation 3.1 Hydrothermal ore-forming processes :DWHUSURSHUWLHV )DFWRUVHVVHQWLDORIK\GURWKHUPDORUHIRUPDWLRQ 3.2 Hydrothermal type deposits (Ⱥ) Metasomatic-hydrothermal: *UHLVHQDQGDOELWLWHGHSRVLWV 6NDUQGHSRVLWV (B) Magmatic-hydrothermal: 3RUSK\U\GHSRVLWV 9ROFDQRJHQLF0DVVLYH6XOILGH 906 GHSRVLWV ,URQ2[LGH&RSSHU*ROG ,2&* GHSRVLWV Introduction that possess features (e.g., morphology, style of mineralization, or composition) suggesting a genetic relationship; a PHWDOORJHQLF HSRFK is a Mineral deposits are economic concentrations of useful elements in the geological time interval of formation of one or more kinds of mineral Earth’s crust, from which they can be extracted at a profit. For this reason, deposits. The size of a metallogenic province can be of regional scale (e.g. the existence of a concentrating geological process is crucial. Ukrainian Shield), and a metallogenic epoch can be as broad as whole There are four basic geological requirements for any ore deposit to be geologic period (e.g. Archean period of gold greenstone mineralization). formed: To describe spatial and temporal relations between ores and host rocks 1) possible source for useful ore components; such terms as V\QJHQHWLF and HSLJHQHWLF are used in genetic descriptions of 2) transportation of these components to the site of ore deposit formation mineral deposits. Syngenetic indicates that ore minerals have formed at the 3) deposition (accumulation) of these components in the ore body as ore same time as their host rock and it is commonly used for sedimentary rocks. minerals; By contrast, epigenetic means that the ore minerals have emplaced in pre- 4) geological setting that allows to preserve ore deposit in the geologic existing host rocks (e.g., veins). time. Other used terms are K\SRJHQH and VXSHUJHQH. The former refers to ores One of the most typical characteristics of mineral deposit is the formed by ascending solutions, whereas the latter deals with ore formation association of specific ore types with certain assemblages of crustal host- by descending solutions, classically meteoric waters interacting with rocks rock. In general, this association represents the geological environment and during surficial weathering. processes that result in formation of mineralization. Many terms are used in relation to the shape of a mineral deposit since it The main aim of ore geologists is to know the nature of these ore- is very variable, from concordant tabular and stratiform to discordant veins forming processing and to understand how these processes work within and breccia bodies. certain geological environment. This knowledge has been commonly and Mineral deposits can be named according to different criteria. successfully utilized for searching new deposits. Sometimes the name of a place, region, or city is used (e.g., Alpine type, The particular elemental composition of a mineral deposit results from a Sudbury type, Cyprus type, Mississippi Valley type). Other times the complicated interaction of favorable combinations of source, transport, and deposits are known using their acronyms (e.g., BIF means banded iron depositional variables. Thus, the type, character, and abundance of an ore formation ores, MVT means Mississippi Valley-type lead-zinc ores, or deposit reflect the environment in which it was formed. It preserves SEDEX means sedimentary exhalative ore). In addition, the deposits may evidence for the evolution of ore-forming processes and tectonic setting as be called according to the rock type, like pegmatitic (large crystals), well as the characteristics of the aWmosphere and hydrosphere. porphyry copper (disseminated stockwork linked to plutonic intrusives), In order to describe and define any mineral deposits ore geologists and skarn (calc-silicate rock). Finally, deposits can be known by their commonly use basic terminology which is not used in other Earth’s Science shape, being the most representative example a type of uranium deposits, disciplines. namely, roll-front uranium deposit. A term PLQHUDO GHSRVLW is used to define a several ore bodies that To describe all the variety of mineral deposits different type includes useful elements (or minerals) which average abundance is enough classifications are widely used in common geological practice. to have potential economic importance. An RUHERG\ refers to a specific volume of material in a mineral deposit that can be mined and marketed at a reasonable profit under the prevailing conditions of commodity prices, costs, and technology. Such terms as metallogenic maps, metallogenic provinces, and metallogenic epochs are usually used in the branch of metallogeny. 0HWDOORJHQ\ is the study of the genesis of mineral deposits, with emphasis on their relationships in space and time to geological features of the Earth’s crust. A PHWDOORJHQLF SURYLQFH may be defined as a mineralized area or region containing mineral deposits of a specific type or a group of deposits Part 1. Formation and interpretation of mineral deposits sedimentary deposits are commonly syngenetic and formed at the same time as the host rock. 1.1. Mineral deposit classification Although many ores are metamorphosed it is evident that metamorphism does not itself represent a fundamental process ore deposits are created. There are two main classifications of mineral deposits that are widely Hydrothermalism, however, is a viable analogue in ore-forming processes used in the world. The first one, industrial classification is based on for metamorphism and also involves modification of either igneous or ɫommodities produced as a result of mining activity with subsequent sedimentary
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