3D modelling of gold occurrence in SW Greenland

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  • BACHELOR THESIS: 3D modelling of hydrothermal altera>on and Au mineralisa>on in the Nuuluk area

    Tartoq gold province (SW Greenland)

    Sara E. Horitz Done in co-opera>on with University of Copenhagen and Geological Survey of Denmark and Greenland

  • Nuuluk

    Figur Map showing location of Nuuluk in SW Greenland and the regional geology. Map is modified after GEUS (figure: Henriksen 1968, Escher og Jensen 1974, Jensen 1975)

    Figur Map of the loca>on of dierent drill cores (red dots), both diamond drilling in the west and winkie drillings in the east along with surface samples shown by their gold value (Figur: King,1985)

  • Background

    More than 40 years of explora>on Two parallel altera>on zones of old meta-volcanics in a classic greenstone belt which has been hydrothermally altered by carboniferous uids

    Rock types are schist and hydrothermal altered meta-volcanics

    12.30 ppm in the Eastern zone 6.63 ppm in the Western zone

  • METHODE

  • Cross sec>ons

    DH5 125m

    surfaceAu (78 ppb, projected)Au (132 ppb, projected)

    Au (730 ppb/2m)Au (217 ppb/2m)

    West East

    Pro!le A

    DH1 134 m

    DH2109 m

    Au (6.65 ppm/2m)

    Au (86 ppb/4m)Au (516 ppb/2m)

    Au (61 ppb) Au (887 ppb)

    DH3

    DH4

    surface

    Au (127 ppb/4m)

    Au (68 ppb/4m)

    97 m

    109 m

    West East

    DH1 & DH2 DH3 & DH4

    DH5

  • Geochemical features Profile log and sample analysis

  • Imported data

    From reports from Nunaoil, Greenex and GEUS

    Drill hole data Loca>on, depth, azimuth and dip Lithology Measurements of Au, As and Cu Structural measurements

    Surface samples -> topography

  • Lithology

  • Lithology

  • Lithology - Structures

  • Gold occurrences

    Western upper zone

    Eastern, northern zone

    Western lower zone Eastern, southern zone

    HALOES: Red: 95< ppb (!) Orange: 80-95 ppb Yellow: 60-80 ppb Bright: 50-60 ppb

  • Lithology + Gold occurences

  • Results Modelling of gold volumes are possible in spite of low

    values and gives a good idea over the poten>al in the area The gold is in boundary zones with lower stability but in

    dierent rock types structures ? There are at least four mineraliza>on zones Gold correlates with As and Cu There is a connec>on with high gold values and the

    graphite- and magne>te schist Old and new data can give a 3D view of the geometry of

    the gold occurrences More data is needed GEUS: Project re-opened and area will be more

    inves>gated next eld season