DOCSLIB.ORG

Laterite and Lateritic Soils and Other Problem Soils

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

LATERITE AND LATERITIC SOILS AND OTHER PROBLEM SOILS AFRICA An Engineering Study for AGENCY FOR INTERNATIONAL DEVELOPMENT AID/csd-2164 I 1 LYON ASSOCIATES, INC. I Baltimore, MaryIand, U. S. A. 1 I BUILDING & ROAD RESEARCH INSTITUTE, t Kumrsi, Ghana - - -. i 1 1 BESTAV/4!LABLE COPY : LATERITE AND LATERITIC SOILS AKD OTHER PROBLEM SOILS AFRICA DEVELOPMENT OF ENGINEERING STAND- ARDS AND CRITERIA FOR THE USAGE OF LATERITE, LATERITIC SOILS, AND OTHER PROBLEM SOILS IN CONNECTION WITH THE CONSTRUCTION OF ROADS, HIGHWAYS AND AIRFIELDS An Engineering Study for AGENCY FOR INTERNATIONAL DEVELOPMENT AID/csd-2164 June, 1971 LYON ASSOCIATES, INC. Baltimore, Maryland, U. S.A. B'CI'ILDING & ROAD RESEARCH INSTITUTE, Kumasi, Ghana TABLE OF CONTENTS Page No . Acknowledgements ........................................... ix-x-xi Chapter 1. Introduction .......................................... 1 Conclusions .............................................. 2 Chapter 2. Engineering Implications of Tropical Weathering and Laterization .................... 5 Introduction .............................................. 5 Weathering ............................................... 5 Profiles of Weathering .......................................... 6 Hydrated and Dehydrated Laterite ..................................... 6 Conclusion ............................................... 6 Chapter 3. Regional Setting and Genetic Classification .............................. 9 Summary of Physiography and Geology of Africa .............................. 9 Geology of Ghana ............................................ 13 Soil Forming Factors and Profile Development ............................... 14 References ............................................... 27 Chapter 4. Literature Review on the Engineering Characteristics of Lateritic Soils .................. 29 Introduction .............................................. 29 Chemical. Mineralogical and Physico-Chemical Characteristics ......................... 29 Physical and Engineering Properties .................................... 30 Density and Compaction Characteristics .................................. 33 Consolidation and Permeability Characteristics ............................... 34 Utilization of Lateritic Soils ....................................... 34 Stabilization of Lateritic Soils ....................................... 35 References ............................................... 36 Chapter 5. Engineering Properties of Tropically Weathered African Soils ...................... 39 Introduction .............................................. 39 Soil Grouping ............................................. 39 Discussion ............................................... 39 Correlation of Physical and Engineering Properties .............................. 45 Effects of Drying on Properties ...................................... 51 Summary of Findings Regarding Major Groups ............................... 56 Collapsing Soils ............................................. 57 Conclusions .............................................. 57 References ............................................... 57 Chapter 6. Test Procedures and Pretreatment ................................. 61 Introduction .............................................. 61 Procedures ............................................... 61 Durability and Aggregate Strength ..................................... 69 Expansion ............................................... 72 Conclusions and Recommendations .................................... 73 References ............................................... 75 Chapter 7. Air Photo Interpretation ..................................... 77 Introduction .............................................. 77 Identification of Laterites and Other Tropical Soils .............................. 77 Color Photography for Present Study ................................... 80 Description of Plates 1. 2 and 3 ...................................... 81 Description of Plates 4. 5 and 6 ...................................... 81 References ............................................... 81 Chapter 8. Suitability of Current Engineering Classification Systems for Tropically Weathered Soils ........... 83 Introduction .............................................. 83 Applicability of Existing Classification Systems ............................... 83 References ............................................... 85 Chapter 9. Stabilization of Selected African Lateritic Gravels and Soils ....................... 87 Introduction .............................................. 87 Scope ................................................. 87 Materials ............................................... 87 Procedures for Lime and Cement ..................................... 87 pHMethod .............................................. 91 Sand Stabilization ............................................ 91 Asphalt Stabilization .......................................... 91 Results and Discussion .......................................... 91 Asphalt Stabilization .......................................... 107 Conclusions .............................................. 108 References ............................................... 110 Chapter 10. Proposed Pavement Test Sections ................................. 113 Introduction .............................................. 113 Selection of Factors ........................................... 113 Strength ................................................ 113 Base Thickness ............................................. 113 Load Factors .............................................. 113 Regional Factors ............................................ 113 Number of Test Lengths Within One Region ................................. 115 Lengths of Sections ........................................... 115 . Construction Control .......................................... 115 Testing Program ............................................ 115 References ............................................... 116 Chapter 11. A Survey of Pavement Design Procedures in Africa .......................... 117 Introduction .............................................. 117 Design Procedures ............................................ 117 Material Specifications .......................................... 118 Conclusion ............................................... 120 References ............................................... 120 Chapter 12. Pavement Condition Survey ................................... 121 Introduction .............................................. 121 Scope ................................................. 121 Procedure ............................................... 121 Results ................................................ 126 Analysis and Discussion ......................................... 129 Detailed Investigation .......................................... 133 Conclusions and Findings ........................................ 141 References ............................................... 141 Chapter 13. Pavement Design Procedures and Specifications for Tropical Soils .................... 143 Introduction .............................................. 143 Design Procedure ............................................ 143 Design Charts ............................................. 143 Specifications ............................................. 146 Discussion ............................................... 147 Chapter 14. Applications of Tropical Soils in Construction Other Than in Roads or Highways ............. 151 Building Materials ............................................ 151 Foundations .............................................. 152 Slopes in Lateritic Soils ......................................... 153 Earth Dams .............................................. 159 References ............................................... 161 Chapter 15. A Review of the Literature on Tropical Black Clays and Black Cotton Soils ............... 163 Introduction .............................................. 163 Definitions ............................................... 163 Occurrences .............................................. 163 Morphological. Chemical and Mineralogical Characteristics ........................... 166 Environment and Formation of Black Tropical Soils ............................. 168 Geotechnical Properties of Tropical Black Clays ............................... 170 Engineering Properties .......................................... 170 References ............................................... 177 Chapter 16. Geographical Distribution and Physical Properties of African Black Clay Soils .............. 183 Introduction .............................................. 183 Scope ................................................. 183 Geographical Distribution ........................................ 183 Test Procedures and Results ....................................... 186 Discussion of Properties ......................................... 191 Conclusions .............................................. 197 References ............................................... 198 Chapter 17. Design Considerations for Roads over Tropioal Black Clays ...................... 199 Introduction .............................................. 199 Recent Design Practices ......................................... 199 Stabilization .............................................. 202 Recommended Design Procedure ....................................
Recommended publications
  • Engineering Behavior and Classification of Lateritic Soils in Relation to Soil Genesis Erdil Riza Tuncer Iowa State University

    Engineering Behavior and Classification of Lateritic Soils in Relation to Soil Genesis Erdil Riza Tuncer Iowa State University

    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1976 Engineering behavior and classification of lateritic soils in relation to soil genesis Erdil Riza Tuncer Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Civil Engineering Commons Recommended Citation Tuncer, Erdil Riza, "Engineering behavior and classification of lateritic soils in relation to soil genesis " (1976). Retrospective Theses and Dissertations. 5712. https://lib.dr.iastate.edu/rtd/5712 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This material was produced from a microfilm copy of the original document. While the most advanced technological means to photograph and reproduce this document have been used, the quality is heavily dependent upon the quality of the original submitted. The following explanation of techniques is provided to help you understand markings or patterns which may appear on this reproduction. 1. The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting thru an image and duplicating adjacent pages to insure you complete continuity. 2. When an image on the film is obliterated with a large round black mark, it is an indication that the photographer suspected that the copy may have moved during exposure and thus cause a blurred image.
  • A Review of the Birimian Supergroup- and Tarkwaian Group-Hosted Gold Deposits of Ghana

    A Review of the Birimian Supergroup- and Tarkwaian Group-Hosted Gold Deposits of Ghana

    177 A review of the Birimian Supergroup- and Tarkwaian Group-hosted gold deposits of Ghana Albertus J. B. Smith1,2*, George Henry1,2 and Susan Frost-Killian3 1 DST-NRF Centre of Excellence for Integrated Mineral and Energy Resource Analysis, Department of Geology, University of Johannesburg, Auckland Park, 2006, South Africa. *Corresponding author e-mail address: [email protected] 2 Palaeoproterozoic Mineralisation Research Group, Department of Geology, University of Johannesburg, Auckland Park, 2006, South Africa 3 The MSA Group, 20B Rothesay Avenue, Craighall Park, 2196, South Africa DOI: 10.18814/epiiugs/2016/v39i2/95775 Ghana is the largest producer of gold in West Africa, veins. The vein- and sulphide-hosted gold is strongly a region with over 2,500 years of history with regards to associated with deformational fabrics formed by the gold production and trade. Modern exploration for and Eburnean extensional and compressional events, mining of gold in Ghana dates from 1874 with the respectively, suggesting that disseminated sulphide establishment of the British Gold Coast Colony, which mineralisation predates quartz vein-hosted was followed in 1957 by the independence of Ghana and mineralisation. The fluid from which the gold precipitated increased gold production since the early 1980s through is believed to have been of metamorphic origin and Ghana’s Economic Recovery Plan. At the time of writing, carbon dioxide (CO2) dominated, with lesser water (H2O) gold production (108.2 tonnes or 3.48 million ounces and nitrogen (N2) and minor methane (CH4). Gold [Moz] in 2014) accounted for approximately one-third precipitation was probably caused by decrease in of Ghana’s export revenues, with 36% of gold production pressure, temperature and CO2-H2O immiscibility, at coming from small-scale mining.
  • Stability of Superparamagnetic Minerals in Soils and Rocks 0.5Ex

    Stability of Superparamagnetic Minerals in Soils and Rocks 0.5Ex

    Stability of superparamagnetic minerals in soils and rocks Can frequency-dependent susceptibility be used as a proxy for climate in the past? Jan Igel1, Holger Preetz1;2 & Christian Rolf1 1Leibniz Institute for Applied Geophysics, Hannover, Germany Leibniz Institute for 2OFD Niedersachsen, Federal Competence Center for Soil and Applied Geophysics Groundwater Protection / UXO Clearance, Hannover, Germany Motivation Results & Interpretation I Frequency-dependent (FD) magnetic susceptibility is a property of I Samples treated with oxygen free water and samples treated superparamagnetic (SP) minerals. The presence of these minerals with sodium sulphide (shown here) show similar results. in soils and sediments is commonly attributed to neoformation Magnetic susceptibility during weathering and pedogenesis. 55000 Warm and humid conditions give rise to neoformation of SP mi- 50000 I Rocks: after dithionite 45000 reduction experiment Tuff nerals and thus frequency-dependent susceptibility is often used as treatment Tephra palaeoclimate proxy in sediment stratigraphy. Rhyolite SI] 40000 6 − I SP minerals can also be of lithogenic origin and occur in magmatic [10 Soils: LF rocks and volcanic ashes. However, a lithogenic origin is commonly κ ≈ Luvisol Humous loess 10000 Laterite neglected in palaeoclimatic studies. Terra Rossa I Pedogenic SP minerals are assumed to be less stable than lithoge- 5000 nic SP minerals. 0 0 50 100 150 200 250 time [days] Materials I No decrease of κLF or ∆κ in reducing environment ! SP minerals stable regardless of their origin (lith./ped.) A number of 7 samples with high I Some soils show increase of κLF and ∆κ during reduction content of SP minerals were in- ! neoformation of SP minerals due to bacterial activity vestigated.
  • DOGAMI MP-20, Investigations of Nickel in Oregon

    DOGAMI MP-20, Investigations of Nickel in Oregon

    0 C\1 a: w a.. <( a.. en ::::> 0 w z <( __j __j w () en � INVESTIGATIONS OF NICKEL IN OREGON STATE OF OREGON DEPARTMENT OF GEOL.OGY AND MINERAL. IN OUSTRIES DONAL.D .A HUL.L. STATE GEOLOGIST 1978 STATE OF OREGON DEPARTMENT OF GEOLOGY AND MINERAL INDUSTRIES 1069 State Office Building, Portland, Oregon 97201 MISCELLANEOUS PAPER 20 INVESTIGATIONS OF NICKEL IN OREGON Len Ramp, Resident Geologist Grants Pass Field Office Oregon Department of Geology and Mineral Industries Conducted in conformance with ORS 516.030 . •. 5 1978 GOVERNING BOARD Leeanne MacColl, Chairperson, Portland Talent Robert W. Doty STATE GEOLOGIST John Schwabe Portland Donald A. Hull CONTENTS INTRODUCTION -- - ---- -- -- --- Purpose and Scope of this Report Acknowledgments U.S. Nickel Industry GEOLOGY OF LATERITE DEPOSITS - -- - 3 Previous Work - - - - --- 3 Ultramafic Rocks - ----- --- 3 Composition - - -------- - 3 Distribution ------ - - - 3 Structure - 3 Geochemistry of Nickel ---- 4 Chemical Weathering of Peridotite - - 4 The soi I profile ------- 5 M i nero I ogy -- - ----- 5 Prospecting Guides and Techniques- - 6 OTHER TYPES OF NICKEL DEPOSITS - - 7 Nickel Sulfide Deposits- - - - - - 7 Deposits in Oregon 7 Other areas --- 8 Prospecting techniques 8 Silica-Carbonate Deposits - -- 8 DISTRIBUTION OF LATERITE DEPOSITS - ------ 9 Nickel Mountain Deposits - - ------ --------- 9 Location --------------- --- 9 Geology - ------- ----- 11 Ore deposits ----------- - -- 11 Soil mineralogy - ------- 12 Structure --- ---- ---- 13 Mining and metallurgy ------------ ---- 13 Production-
  • World Reference Base for Soil Resources 2014 International Soil Classification System for Naming Soils and Creating Legends for Soil Maps

    World Reference Base for Soil Resources 2014 International Soil Classification System for Naming Soils and Creating Legends for Soil Maps

    ISSN 0532-0488 WORLD SOIL RESOURCES REPORTS 106 World reference base for soil resources 2014 International soil classification system for naming soils and creating legends for soil maps Update 2015 Cover photographs (left to right): Ekranic Technosol – Austria (©Erika Michéli) Reductaquic Cryosol – Russia (©Maria Gerasimova) Ferralic Nitisol – Australia (©Ben Harms) Pellic Vertisol – Bulgaria (©Erika Michéli) Albic Podzol – Czech Republic (©Erika Michéli) Hypercalcic Kastanozem – Mexico (©Carlos Cruz Gaistardo) Stagnic Luvisol – South Africa (©Márta Fuchs) Copies of FAO publications can be requested from: SALES AND MARKETING GROUP Information Division Food and Agriculture Organization of the United Nations Viale delle Terme di Caracalla 00100 Rome, Italy E-mail: [email protected] Fax: (+39) 06 57053360 Web site: http://www.fao.org WORLD SOIL World reference base RESOURCES REPORTS for soil resources 2014 106 International soil classification system for naming soils and creating legends for soil maps Update 2015 FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Rome, 2015 The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO.
  • The Geology of the Gold Deposits of Prestea Gold Belt of Ghana*

    The Geology of the Gold Deposits of Prestea Gold Belt of Ghana*

    The Geology of the Gold Deposits of Prestea Gold Belt of Ghana* K. Dzigbodi-Adjimah and D. Nana Asamoah Dzigbodi-Adjimah, K. and Nana Asamoah, D., (2009), “The Geology of the Gold Deposits of Prestea Gold Belt of Ghana”, Ghana Mining Journal, Vol. 11, pp. 7 - 18. Abstract This paper presents the geology of the gold deposits along the Prestea gold belt of Ghana to assist exploration work for new orebodies along the belt. Prestea district is the third largest gold producer in West Africa after Obuasi and Tarkwa districts (over 250 metric tonnes Au during the last century). The gold deposits are structurally controlled and occur in a deep-seated fault or fissure zone that is regarded as the ore channel. This structure, which lies at the contact between metavolcanic and metasedimentary rocks in Birimian rocks, is more open (and contains more quartz lodes) at the southern end around Prestea than at Bogoso to the north. The gold deposits consist of the Quartz Vein Type, (QVT) and the Dis- seminated Sulphide Type (DST). The QVT orebodies, which generally carry higher Au grades, lie within a graphitic gouge in the fissure zones whilst the DST is found mostly in sheared or crushed rocks near the fissure zones. Deposits were grouped into three in terms of geographic location and state of development; The deposits south of Prestea are the least developed but have been extensively explored by Takoradi Gold Company. Those at Prestea have been worked exclusively as underground mines on QVT orebodies by Prestea Goldfields Limited and its forerunners; Ariston and Ghana Main Reef companies until 1998 whilst the deposits north of Prestea, which were first worked as surface mines (on DST orebodies) by Marlu Mines up to 1952, were revived by Billiton Bogoso Gold in 1990.
  • S41598-021-96384-7.Pdf

    S41598-021-96384-7.Pdf

    www.nature.com/scientificreports OPEN A mechanical insight into the triggering mechanism of frequently occurred landslides along the contact between loess and red clay Baoqin Lian1, Xingang Wang1*, Kai Liu1, Sheng Hu2 & Xiao Feng3 The triggering mechanism and movement evolution of loess-red clay landslides, which occurred frequently along the contact between the loess and red clay on the Loess Plateau, are closely related to the mechanical properties of the contact surface. This work presents an experimental investigation on loess, clay and loess-red clay interlaminar (LRCI) samples obtained from a typical loess-red clay landslide in northern part of Shaanxi province of China, using a series of ring shear tests, microscopic observation and scanning electron microscopy tests, in an attempt to explore the mechanical behavior of loess, clay and LRCI samples with variation in moisture content, normal stress and shear rate. The results revealed that for all specimens, both the peak shear strength τp and the residual shear strength τr decreased with increasing moisture content, among which, moisture content has the greatest infuence on the τp and τr of red clay, followed by the LRCI specimen, and the loess specimen is least afected by moisture content. Meanwhile, exponential functions describing the correlations between shear strength and moisture content of LRCI, red clay and loess specimens were proposed. Furthermore, the macroscopic morphological characteristics and the microstructure of shear surface obtained from the LRCI specimens showed that a localized water accumulation was built up within the shear surface as the water content increases to some extent, and a high degree of liquefaction developed within shear surface when the moisture content reached to the saturate degree.
  • I U R E P Orientation Phase R E P O R T G H a 1\F A

    I U R E P Orientation Phase R E P O R T G H a 1\F A

    International Atomic Energy Agency DRAFT I U R E P ORIENTATION PHASE REPORT G H A 1\F A MR. JEW-PAUL GUELPA MR. WOLFRAM TO GEL December 1982 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document UTTEENATIOITAL URANIBK RESOURCES. EVALUATION PROJECT -IURBP- IUSSP ORIENTATION FHAS3 MISSION REPORT BSPTOLIC OP GHANA Dr. J.Fo Guelpa December, 1982. Dro "W. Vogel PREFACE mission, was undertaken, by two consultants, Dr. JoP. Guelpa and Dr. W, Vogel, both, commenced the investigations in Ghana on 5th November, 1982 and completed their work on 16th December, 1982. A total of three days was spent in the field by the consultants* 1. Terse of Ilsferenie .. ., 5 2. General Geography .. .. 4 3. Clirate .. ... 7 4. Population aril I-lain Cities .. .. 9 5. Administrative Regions .. .. S- 6. Official Language, Public Holidays and System of Eeasureaervfc .. ., ll 7. Transport and Consronicatipn .. .. 11 8. Available "aps and Air Photographs .. 12 c. ITCK UB^ITK ICIITIKG n; GH^A • .. .. 13 1. Overview .. .. 13 2. Dianond .. ,. 15 3. Gold .. .. 17 . • 4. Batfzite .. • .. 'IS 5. Manganese .. .. 18 D. IBGI3LATICH ON UEAiTITJK EXPLCHASCtf AlTD XIIIDTG 19 3. KATIOKAL CAFACITI PCS URAFIUI! SXPLORATIC1T AIT3 D272L0P- 1. Ghana Atoiaic Energy CoEE&ssion .. 20 2. Ghana Geological Survey .. .. 22 3. Universities .. .. 24 F. GnOL'OGIC/i 3ST.12r.7 . .. 25 1. Introduction .. ' .. 25 2. The 'vest African Shield Area .. .. 27 2.1 Birician Systec .. .. 27 2.2 Eburnean Granites .. .. 32 2.3 Taria-;aian System .. .. 35 3. Sie Kobile Belt ... .. 3S 3.1 Dahoneyan System •• •• 35 3.2 ?cgc Series •• •• 4C 3 .3 Buen.
  • Geotechnical Properties of Lateritic Soil Stabilized with Periwinkle Shells Powder

    Geotechnical Properties of Lateritic Soil Stabilized with Periwinkle Shells Powder

    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 5 November 2018 doi:10.20944/preprints201811.0100.v1 Article GEOTECHNICAL PROPERTIES OF LATERITIC SOIL STABILIZED WITH PERIWINKLE SHELLS POWDER Abiola. M. Dauda1, Joseph O. Akinmusuru1, Oluwaseun. A. Dauda1, Taiwo O. Durotoye1, and Kunle E. Ogundipe*2 Kehinde O. Oyesomi3 [email protected]; [email protected]; [email protected]; [email protected]; [email protected] 1 Department of Civil Engineering, Covenant University, Ota 112233, Ogun State Nigeria. 2 Department of Building Technology, Covenant University, Ota 112233, Ogun State Nigeria. 3 Department of Mass Communication, Covenant University, Ota 112233, Ogun State Nigeria. *Corresponding Author: [email protected]; Tel.: +234-806-237-1086 Abstract: This study used eco-friendly materials known as Periwinkle Shell Powder (PSP) in stabilizing the engineering properties of lateritic soil. Preliminary test was performed on the un-stabilized lateritic soil for the purposes of identification and classification (natural moisture content, liquid limits, plastic limits, and plasticity index). The engineering tests were conducted on the lateritic soil stabilized with additions of (2, 4, 6, 8 and 10 %) PSP and OPC respectively. The result showed that cement gave a progressive increase in the Maximum Dry Density (MDD) of the lateritic soil from 1875 kg/m3 (2 %) to 2294 kg/m3 (10 %) respectively. This represents 22 % increase in the MDD from the un-stabilized state. For PSP, the Maximum MDD was attained at 6 % (1974 kg/m3), representing 5.3 % increase in MDD of the soil from the un-stabilized state. For both stabilizing agent, the Optimum Moisture Content (OMC) increases from 13.65 % to 13.83 % and from 11.72 % to 14.41 % for Cement and Periwinkle Shell Powder respectively.
  • Open-File 77-885

    Open-File 77-885

    UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY PROJECT REPORT Nigerian Investigation (IR)N-I Open-File 77-885 PRELIMINARY ENGINEERING GEOLOGIC REPORT ON SELECTION OF URBANSITES IN THE FEDERAL CAPITAL TERRITORY, NIGERIA Prepared by the U. S. Geological Survey for the Federal Capital Development Authority of Nigeria 1977 Open file report (IR)N-l PRELIMINARY ENGINEERING GEOLOGIC REPORT ON SELECTION OF URBAN SITES IN THE FEDERAL CAPITAL TERRITORY, NIGERIA CONTENTS SUMMARY ...................................................... INTRODUCTION ................................................. 5 Location ................................................... 5 Purpose and method of study ................................ 5 Acknowledgments ............................................ 8 BEDROCK GEOLOGY .............................................. 9 Precambrian rocks .......................................... 11 Metamorphic rocks ........................................ 11 Igneous rocks ............................................ 19 Cretaceous sedimentary rocks ............................... 21 Tertiary laterite .......................................... 24 Quaternary alluvium .................................... f ... 24 Geologic structure ......................................... 25 Central fold ............................................. 25 Eastern shear zone ....................................... 25 Northwest-trending faults and fractures .................. 28 Mineral deposits ........................................... 28 Tin deposits
  • Asanko Report

    Asanko Report

    Technical Report on Asanko Gold Project, Ashanti Region Ghana 1 An Independent Qualified Persons’ Report On ASANKO GOLD MINE in the Ashanti Region, Ghana Effective Date: 30 September 2014 Issue Date: 24 October 2014 Reference: AGM_001 Authors: CJ Muller (Director): B.Sc. (Hons) (Geol.) Pr. Sci. Nat A. Umpire (Geology Manager) B.Sc. (Hons.) (Geol. Eng.), Pr.Sci.Nat B.Sc. Hons. (IT) MBA Suite 4 Coldstream Office Park Cnr Hendrik Potgieter & Van Staden Streets Little Falls, Roodepoort, South Africa Tel: +27 │ Fax: +27 Directors:, CJ Muller Registration CJM Consulting Technical Report on Asanko Gold Project, Ashanti Region Ghana 2 INFORMATION RISK This Report was prepared by CJM Consulting (Pty) Ltd (“CJM”). In the preparation of the Report, CJM has utilised information relating to operational methods and expectations provided to them by various sources. Where possible, CJM has verified this information from independent sources after making due enquiry of all material issues that are required in order to comply with the requirements of the NI 43-101 and SAMREC Reporting Codes. OPERATIONAL RISKS The business of mining and mineral exploration, development and production by their nature contain significant operational risks. The business depends upon, amongst other things, successful prospecting programmes and competent management. Profitability and asset values can be affected by unforeseen changes in operating circumstances and technical issues. POLITICAL AND ECONOMIC RISK Factors such as political and industrial disruption, currency fluctuation and interest rates could have an impact on future operations, and potential revenue streams can also be affected by these factors. The majority of these factors are, and will be, beyond the control of any operating entity.
  • Petrography of Detrital Zircons from Sandstones of the Lower Devonian Accraian Formation, SE Ghana: Implications on Provenance

    Petrography of Detrital Zircons from Sandstones of the Lower Devonian Accraian Formation, SE Ghana: Implications on Provenance

    Received: 13 February 2019 Revised: 19 June 2019 Accepted: 4 August 2019 DOI: 10.1002/gj.3633 RESEARCH ARTICLE Petrography of detrital zircons from sandstones of the Lower Devonian Accraian Formation, SE Ghana: Implications on provenance Chris Y. Anani1 | Richard O. Anim1 | Benjamin N. Armah1 | Joseph F. Atichogbe1 | Patrick Asamoah Sakyi1 | Edem Mahu2 | Daniel K. Asiedu1 1 Department of Earth Science, University of Ghana, Accra, Ghana Integrated petrographic studies entailing quartz‐type analysis and zircon typologic 2 Department of Marine Fisheries Sciences, studies were carried out on sandstones of the Lower Devonian Accraian Formation University of Ghana, Accra, Ghana of southern Ghana to constrain their provenance and tectonic setting. The stratigraphic Correspondence succession of the Devonian Accraian Group consists mainly of sandstones in the Lower Chris Y. Anani, Department of Earth Science, – University of Ghana, PO Box LG 58, Legon, Accraian Formation, shales in the Middle Accraian Formation, and sandstone shale Accra, Ghana. intercalations in the Upper Accraian Formation. Systematic sampling of sandstones Email: [email protected]; agbekoen@yahoo. com was conducted in the Lower Devonian Accraian Formation. Modal petrographic analy- sis indicates that the sandstones are quartz arenites with their framework grains Funding information Department of Earth Science Capacity Building consisting on average of, 99.8% quartz, 0.14% lithics with little or no feldspars. They Project, University of Ghana are subangular to subrounded in shape. Modal mineralogy of the sandstones suggests Handling Editor: I. Somerville that they are of craton interior origin with an affinity to recycled orogenic provenance. Quartz‐type analysis was used to unravel distinct characteristic features of the quartz grain, namely its polycrystallinity, nonundulose, and undulose nature to constrain the source rock.