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Geochemistry of Granitic Aplite-Pegmatite Veins and Sills and Their Minerals from the Sabugal Area, Central Portugal
N. Jb. Miner. Abh. 188/3, 297 – 316 Fast Track Article PublishedStuttgart, Augustonline November2011 2011 Geochemistry of granitic aplite-pegmatite veins and sills and their minerals from the Sabugal area, central Portugal Ana M. R. Neiva, Paulo B. Silva and João M. F. Ramos With 19 fi gures and 12 tables Abstract: Granitic beryl-columbite-phosphate subtype aplite-pegmatite veins and sills from the Sabugal area intruded a biotite > muscovite granite which is related to another two-mica granite. Variation diagrams of major and trace elements of whole rocks δ18 show fractionation trends. REE patterns and O of whole rocks, BaO and P2O5 contents of K-feldspar, anorthite and P2O5 contents of plagioclase, major element and Li contents of muscovite and lithian muscovite support this series. Least squares analysis of ma- jor elements indicate that the biotite > muscovite granite and aplite-pegmatite veins and sills are derived from the earlier two-mica granite magma by fractional crystallization of quartz, plagioclase, K-feldspar, biotite and ilmenite. Modelling of trace elements shows that magmatic fl uxes and fl uids controlled the Rb, Sr and Ba contents of aplite-pegmatites,Paper probably also lithium micas (zin- nwaldite, polylithionite and rare lepidolite), cassiterite, columbite-tantalite, fl uorapatite and triplite. In aplite-pegmatites, lithian muscovite replaces primary muscovite and late lithium micas replace lithian muscovite. Complexely zoned columbite crystals are chemically characterized and attributed to disequilibrium conditions. Relations of granites and aplite-pegmatites and pegmatites from other Portuguese and Spanish areas are compared. The granitic aplite-pegmatites from Sabugal are moderately fractionated and the granitic complex type aplite-pegmatites from Gonçalo are the richest in Li and Sn, derived from a higher degree of frac- tional crystallization and fl uxes and fl uids control the Ba and Rb behaviours and Li, Sn, F and Ta concentrations. -
Decrepitation Characteristics of Igneous
DECREPITATIONCHARACTERISTICS OF IGNEOUSROCKS F. G. SMITH Unfuersi,tyof Toronto, Toronto, Canada Ansrnect ._lecrepitation during heating of igneous intrusive rocks is complex, but one stage (D2) appears to be due to misfit of solid inclusions. This stage begins at 6rb + g0'-b in simple granite pegmatite and aplite, Z0S * 80" C in ganiie, Z6E + 50" C in granodiorite and quartz norite, and 1010 + 60o C in gabbro and related rocks. The p2-sQS! of pegmatite and aplite in an area of migmatitic gneiss, with no exposed batholiths, starts at a lower temperature than the corresponding stage of decrepitation of the country gneiss. Introd,wction The rationale of decrepitation due to misfit of solid inclusions in minerals, when heated above the temperature of crystallization, was outlined previously (smith, L952a).A stage of decrepitation of several types of garnet was interpreted to be due to solid inclusions, becausethe frequency of decrepitation was found to be directly related to the abundanceof solid inclusions (smith, lg52b). A similar stage of decrepi- tation of high grade metamorphic rocks was found (Smith, lgb8). The measuredtemperatures of the beginning of this stage of decrepitation of metamorphic minerals are internally consistent, and are not at variance with the small amount of synthetic data. As a further test of the rationale. a few rocks representing several igneous rock clans were heated in the decrepitation apparatus. The results can be interpreted in an analogous manner to give the temperature of crystallization of the constituent minerals. These data, which should be considered as only tentative becauseof the small number in each clan tested, are given below, uncor- rected for the effect of pressiure. -
Petrographic Study of a Quartz Diorite Stock Near Superior, Pinal County, Arizona
Petrographic study of a quartz diorite stock near Superior, Pinal County, Arizona Item Type text; Thesis-Reproduction (electronic); maps Authors Puckett, James Carl, 1940- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 23/09/2021 23:40:37 Link to Item http://hdl.handle.net/10150/554062 PETROGRAPHIC STUDY OF A QUARTZ DIORITE STOCK NEAR SUPERIOR, PINAL COUNTY, ARIZONA by James Carl Puckett, Jr. A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOLOGY In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 7 0 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of re quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg ment the proposed use of the material is in the interests of scholar ship. In all other instances, however, permission must be obtained from the author. -
University of Nevada, Reno Igneous and Hydrothermal Geology of The
University of Nevada, Reno Igneous and Hydrothermal Geology of the Central Cherry Creek Range, White Pine County, Nevada A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geology by David J. Freedman Dr. Michael W. Ressel, Thesis Advisor May, 2018 THE GRADUATE SCHOOL We recommend that the thesis prepared under our supervision by DAVID JOSEPH FREEDMAN entitled Igneous and Hydrothermal Geology of the Central Cherry Creek Range, White Pine County, Nevada be accepted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Michael W. Ressel, PhD, Advisor John L. Muntean, PhD, Committee Member Douglas P. Boyle, PhD, Graduate School Representative David W. Zeh, PhD, Dean, Graduate School May, 2018 i Abstract The central Cherry Creek Range exposes a nearly intact, 8-km thick crustal section of Precambrian through Eocene rocks in a west-dipping homocline. Similar tilts between Eocene volcanic rocks and underlying Paleozoic carbonates demonstrate that tilting and exhumation largely occurred during post-Eocene extensional faulting, thus allowing for relatively simple paleo-depth determinations of Eocene intrusions and mineral deposits. The study area is cored by the Cherry Creek quartz monzonite pluton (35 km2 exposure; ~132 km2 coincident magnetic anomaly), which was emplaced into Precambrian and Cambrian meta-sedimentary strata between 37.9-36.2 Ma and is exposed along the east side of the range. The pluton and overlying Paleozoic strata are cut by abundant 35.9-35.1 Ma porphyritic silicic dikes. A range of polymetallic mineralization styles are hosted by the intrusive rocks along two deeply-penetrating, high-angle faults and their intersections with favorable Paleozoic units. -
(FP)-Rich Aplite-Pegmatites in the Central Iberian Zone Geologic
Ore Geology Reviews 95 (2018) 408–430 Contents lists available at ScienceDirect Ore Geology Reviews journal homepage: www.elsevier.com/locate/oregeorev Petrogenetic relationships between Variscan granitoids and Li-(F-P)-rich T aplite-pegmatites in the Central Iberian Zone: Geological and geochemical constraints and implications for other regions from the European Variscides ⁎ E. Roda-Roblesa, , C. Villasecab, A. Pesqueraa, P.P. Gil-Crespoa, R. Vieirac, A. Limac, I. Garate-Olavea a Dpto. Mineralogía y Petrología, Universidad del País Vasco UPV/EHU, Barrio Sarriena s/n, 48940 Leioa, Spain b Dpto. Petrología y Geoquímica, Universidad Complutense, IGEO (UCM, CSIC), 28040 Madrid, Spain c Instituto de Ciências da Terra, Universidade do Porto/DGAOT, Rua do Campo Alegre 687, 4169-007 Porto, Portugal ARTICLE INFO ABSTRACT Keywords: The Central Iberian Zone (CIZ) is characterised by a large volume of Variscan granitic intrusions, which can be Li-rich aplite-pegmatites grouped into five types: (1) two-mica peraluminous leucogranites (S1); (2) P-rich highly peraluminous granites Granite batholiths (S2); (3) P-poor moderately peraluminous granites (S3); (4) moderately to low peraluminous granites (S4); and Geochemistry (5) I-type low peraluminous granites (I). Though not as abundant as granites, aplite-pegmatite rocks are Central Iberian Zone nonetheless widespread in this region, occurring either as fields of aplite-pegmatite dykes or as leucogranitic European Variscan Belt cupolas. They are commonly enriched in Li-(F-P) minerals such as spodumene, petalite, micas, and phosphates of the amblygonite-montebrasite and triphylite-lithiophilite series. Many of the Li-rich bodies show an aplitic texture, frequently with the development of layered units. -
Geology of the Pegmatites and Associated Rocks of Maine
DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY GEORGE OTIS SMITH, DIRECTOR BULLETIN 445 GEOLOGY OF THE PEGMATITES AND ASSOCIATED ROCKS OF MAINE INCLUDING FELDSPAR, QUARTZ, MICA, AND GEM DEPOSITS BY EDSON S. BASTIN WASHINGTON GOVERNMENT PRINTING OFFICE 1911 CONTENTS. Introduction.............................................................. 9 Definition of pegmatite...................................................... 10 Geographic distribution.................................................... 10 Geology.................................................................. 10 Bordering rocks....................................................... 10 Pegmatites in foliated rocks........................................ 11 General statement............................................ 11 Sedimentary foliates........................................... 11 Igneous foliates.....".......................................... 12 Pegmatites in massive granites.................................... 13 'Age.................................................................. 15 General character..................................................... 15 Mineral and chemical composition................................. 15 Mineral constituents.......................................... 15 Relative proportions of minerals............................... 18 Quartzose phases. ..............................^............. 18 Fluidal cavities............................................... 19 Sodium and lithium phases................................... 20 Muscovite -
The Sierra Nevada Batholith a Synthesis. of Recent Work Across the Central Part
I _; The Sierra Nevada Batholith A Synthesis. of Recent Work Across the Central Part By PAUL C. BATEMAN, LORIN ~- CLARK, N. KING HUBER, JAMES G. MOORE, and C. DEAN RINEHART SHORTER CONTRIBU.TIONS TO GENERAL GEOLOGY· G E 0 L 0 G I CAL SURVEY P R 0 FE S S I 0 N A L PAPER 414-D Prepared in cooperation with the State of Caltfornia, Division of Mines and Geology · ti II R fA u 0 F u' N f I ._rBRARV SPUI\ANf:.. !NASH. JUN 31971 . ·~-~ - ~ ... -- --s PtfASf RfT,fJR~ fO liBRARY UNITED S.TATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1963 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY Thomas B. Nolan, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C., 20402 CONTENTS Page Abstract------------------------------------------- D1 Constitution' of the batho1ith-Continued Introduction ______________________________________ _ 2 Contact relations _______________ ~ ______ - -- _----- D22 Genernl geologic relations _______________________ _ 2 Contacts between different granitic rocks _____ - 22 Previous geologic work _________________________ _ 4 Contacts between granitic rocks and meta- Acknowledgments _____________________________ _ 5 morphic rocks or diorite ___________ -- __ ---- 22 Wu.llrocks u.nd roof rocks ___________________________ _ 5 Felsic dike swarms __________________ - ___ -------- 24 Pu.leozoic rocks ________________________________ _ 5 Mafic dike swarms _________________________ ----- 25 Mesozoic rocks ________________________________ _ 6 Structure -
Petrography and Engineering Properties of Igneous Rocks
ENGINEERil~G MONOGRAPHS No. I United States Department of the Interior BUREAU OF RECLAMATION PETROGRAPIIY AND ENGINEERING· PROPER11ES OF IGNEOUS ROCKS hy Rit~bard C. 1\lielenz Denver, Colorado October 1948 95 cents (R.evised September 1961) United States Department of the Interior STEWART L. UDALL, Secretacy Bureau of Reclamation FLOYD E. DOMINY, Commissioner G~T BLOODGOOD, Assistant Commissioner and Chief Engineer Engineering Monograph No. 1 PETROGRAPHY AND ENGINEERING PROPERTIRES ·OF IGNEOUS RO<;:KS by Richard C. Mielenz Revised 1959. by William Y. Holland Head. Petrographic Laboratory Section Chemical Engineering Laboratory Branch Commissioner's Office. Denver Technical Infortnation Branch Denver Federal Center Denver, Colorado ENGINEERING MONOGRAPHS are published in limited editions for the technical staff of the Bureau of Reclamation and interested technical circles in Government and private agencies. Their purpose is to record devel opments, innovations, .and progress in the engineering and scientific techniques and practices that are employed in the planning, design, construction, and operation of Rec lamation structures and equipment. Copies 'may be obtained from the Bureau of Recla- · mation, Denver Federal Center, Denver, Colon.do, and Washington, D. C. Excavation and concreting of altered zones in rhyolite dike in the spillway foundation. Davis Damsite. Arizona-Nevada. Fl'ontispiece CONTENTS Page Introduction . 1 General Basis of Classification of Rocks . 1 Relation of the Petrographic Character to the Engineering Properties of Rocks . 3 Engineering J?roperties of Igneous Rocks ................................ :. 4 Plutonic Rocks . 4 Hypabyssal Rocks . 6 Volcanic Rocks..... 7 Application of Petrography to Engineering Problems of the Bureau of Reclamation . 8 A Mineralogic and Textural Classification of Igneous Rocks . -
Geochemistry and Genesis of Beryl Crystals in the LCT Pegmatite Type, Ebrahim-Attar Mountain, Western Iran
minerals Article Geochemistry and Genesis of Beryl Crystals in the LCT Pegmatite Type, Ebrahim-Attar Mountain, Western Iran Narges Daneshvar 1 , Hossein Azizi 1,* , Yoshihiro Asahara 2 , Motohiro Tsuboi 3 , Masayo Minami 4 and Yousif O. Mohammad 5 1 Department of Mining Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj 66177-15175, Iran; [email protected] 2 Department of Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601, Japan; [email protected] 3 Department of Applied Chemistry for Environment, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda 669-1337, Japan; [email protected] 4 Division for Chronological Research, Institute for Space-Earth Environmental Research, Nagoya University, Nagoya 464-8601, Japan; [email protected] 5 Department of Geology, College of Science, Sulaimani University, Sulaimani 46001, Iraq; [email protected] * Correspondence: [email protected]; Tel.: +98-918-872-3794 Abstract: Ebrahim-Attar granitic pegmatite, which is distributed in southwest Ghorveh, western Iran, is strongly peraluminous and contains minor beryl crystals. Pale-green to white beryl grains are crystallized in the rim and central parts of the granite body. The beryl grains are characterized by low contents of alkali oxides (Na2O = 0.24–0.41 wt.%, K2O = 0.05–0.17 wt.%, Li2O = 0.03–0.04 wt.%, Citation: Daneshvar, N.; Azizi, H.; and Cs2O = 0.01–0.03 wt.%) and high contents of Be2O oxide (10.0 to 11.9 wt.%). The low contents Asahara, Y.; Tsuboi, M.; Minami, M.; of alkali elements (oxides), low Na/Li (apfu) ratios (2.94 to 5.75), and variations in iron oxide Mohammad, Y.O. -
Geology of the Fee Sna L Peak Area Baboquivari
Geology of the Fresnal Peak area, Baboquivari Mountains, Arizona Item Type text; Thesis-Reproduction (electronic) Authors Donald, Peter Gordon, 1934- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 02/10/2021 03:15:09 Link to Item http://hdl.handle.net/10150/551311 GEOLOGY OF THE FEE SNA L PEAK AREA BABOQUIVARI MOUNTAINS, ARIZONA by Peter G. Donald A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOLOGY In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College UNIVERSITY OF ARIZONA 1959 -*• ■-» t vvT...-: i V . 1 : r - - t V '• ■r V *. T ’" T - •* -X — .1 •' i * . --. - - . : ’*j 1 ‘ vl I STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of require ments for an advanced degree at the University of Arizona and is de posited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in their judgment the proposed use of the material is in the interests of scholar ship. -
Jahns (1955): the Study of Pegmatites, with References to Bowen (1928, 1933)
Jahns (1955): The Study of Pegmatites, with References to Bowen (1928, 1933) David London ([email protected]) February 24, 2021 Introduction “The Study of Pegmatites” (Jahns, 1955) appeared in the 50th anniversary volume of Economic Geology, a publication of the Society of Economic Geologists in the U.S. (available for purchase at https://www.segweb.org/Store/detail.aspx?id=EDOCAV50). In just two years from his first publications in an academic journal (Jahns, 1953a,b), Richard H. “Dick” Jahns was the recognized leader in the field. The table of contents to that volume incorrectly lists Jahns’ article with the title “The Study of Pegmatite Deposits”, as the emphasis of the volume was on the geology of mineralized systems. Jahns’ article, however, was not concerned with the economic aspects of pegmatites, as was the wartime study of Cameron et al. (1949). Jahns (1955) was meant as a review and treatise on the geologic processes that make pegmatites according to those whose studies preceded him, and it served as a platform upon which to present his own evolving views on the internal evolution of pegmatites. Jahns (1955) contains 698 citations. To those who are not part of the academic realm, and for students too young to know life before the World Wide Web, the effort to track down and read or at least review that many published works in just a few years is an achievement in itself 1. One started with a physical review of journals in paper on stands in libraries and subject indices of books in card catalogs. -
Geologic Guide to Stone Mountain Park
GEOLOGIC GUIDE TO STONE MOUNTAIN PARK by Robert L. Atkins and Lisa G. Joyce Georgia Department of Natural Resources Georgia Geologic Survey GEOLOGIC GUIDE 4 Common Misconceptions About Stone Mountain An average of four million people visit Stone Mountain Park each year. Very little geologic information is available to these visitors. With this lack of information, some misconceptions have developed concerning Stone Moun tain and the granite named after the mountain. Several of these misconcep tions are discussed below. MYTH 1: Stone Mountai n granite underlies half of Georgia, all of Geor gia, three states, seven states, etc. FACT: The Stone Mountain Granite is a relatively small unit. It extends northward to U.S. 78, southward to the park boundary, and its western contact lies within the park limits. It extends eastward towards C enterville (see Geologic Map of the Stone Mountain Area, p. 12-13). MYTH 2: Stone Mountain is the largest exposed granite outcrop in the world. FACT: Stone Mountain's size is quite inspiring. It probably is the largest granite dome east of the Mississippi River, as it rises approxi mately 750 feet (ft) above the surrounding topography; how ever, it is not the largest dome in the world. Many granite domes in the Sierras in the western United States are larger. MYTH 3: Stone Mountain is 300 million years old. FACT: The granite that forms Stone Mountain is approximately 300 million years old, but the mountain itself has only been exposed for approximately 15 million years. MYTH 4: Stone Mountain used to be a volcano. FACT: Although Stone Mountain Granite, like all other granites, is igneous in origin, it was formed quite differently from a volcano.