Training of Economic Geology PhD's - a perspective from NERC Facilities -

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Training of Economic Geology PhD's - a perspective from NERC Facilities -. Adrian Boyce NERC Isotope Community Support Facility at Scottish Universities Environmental Research Centre. What’s a NERC Facility? “A range of specialist analytical facilities to support NERC research.” - PowerPoint PPT Presentation

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Training of Economic Geology PhD's - a perspective from NERC Facilities -

Adrian BoyceNERC Isotope Community Support Facility

at

Scottish Universities Environmental Research Centre

What’s a NERC Facility?“A range of specialist analytical

facilities to support NERC research.”

Isotope Community Support Facility (ICSF)Argon Isotope Facility(AIF)NERC Isotope Geoscience Lab (NIGL)Open Uni U Series Facility(OUUSF)

SUPPORTING GOOD SCIENCE

Supporting UK Earth Science Research Community NERC Themes

Sustainable Use of Natural ResourcesEarth System Science

Environment and Pollution

2000-2010

33 student-based projects involving in-depth training at

ICSF/SUERC

How do we know it’s “Good Science”?

NERC Isotope Geoscience Facilities Steering Committee

≥4 for PI research≥3H for student-based research

ICSF involved often from day one of student projectdevelopment, or NERC grant development

Training often starts with the students being principalauthor of their Facility Proposal

Partnership with Supervisors and Industry

Relevance to Minerals Industry?

90% of students are part funded by Minerals Industry100% are employed, with 75% now in Industry and related posts

Projects from Kazakhstan to Guinea, from Ireland to Peru

Spectrum of Commodities Au, Zn, Pb, Ag, Ba, Sn, Cu, Ni, PGE,

Mo, Fe, V…..

Also working in remediationUnderstanding of AMD issues from deposit perspective

e.g. Iberian Pyrite Belt, Great Northern Coalfield

What do we offer?

ICSF - Stable Isotope Laboratory(S, C, O and H in minerals and fluids)

World’s first in situ laser S system for sulfides and sulfates One of only two sulfate O isotope systems in the UK A total laser fluorination system (≥0.4mg SiO2 equiv) UK’s only fluid inclusion H system Autocarb systems - either for µg calcite or mg mixed carbonates Semi-auto fluid H injection system Fully auto fluid O & H systems

Isotope GeochemistryAccess to truly world-class Isotope Facilities

Rocks and minerals4.6 Ga ( ~ 0.1% precision) to 2 ka (~ 10% precision)

Level of precision obtainable is related to the quality of the samples

AIF - GeochronologyWhat age range does Ar/Ar span?

State-of-the-art ARGUS multi-collector noble gas mass spectrometer

What Ar/Ar can dateAny potassic mineral

but we have to consider probable age of the sample (older the rock or mineral the more 40Ar*)

Nu plasma HR multicollector plasma ionisation mass spectrometer

Thermo Electron Triton thermal ionisation mass spectrometer (TIMS)

NIGL

U-Pb in zircon, monazite, titanite, rutileVery high precision

(1Ma - 4.6Ma)

U-series dating of carbonates (e.g. travertines)(<450kyrs)

Sr, Nd, Pb, Hf - Tracer

Gold in K-feldspar crystal

Date the K-fspr dating gold emplacement

Stable isotopes place the K-fspr in a hydrothermal event

Ar/Ar age spectra and inverse isochron plots

Gave precise age of 405Ma versus

Intrusion age of 410Ma

Hydrothermal Sulfide

Summary of conventional sulfide 34S from the Navan deposit

Bacteriogenic Sulfide

n 10

9

8

7

6

5

4

3

2

1

-20 -10-30 0 10 20

34SCDT (‰)

Coarse textureFine textures

GEOLOGICAL CROSS-SECTION ALONG TRAVERSE LENGTH.

FOOTWALL GREEN SHALE

5-LENS DOLOMITE

BOTTOM DARK MARKER

LOWER DARK MARKER

SUB-LOWER SANDSTONE MARKER

B FAULT COMPLEX

BOULDER CONGLOMERATE(OVERLYING

EROSION SURFACE)

NNWMINOR (NNE, NE & ENE) FAULTING MINOR ENE FAULTING

c. 50 METRES

NODULARMARKER

Stratigraphic interval investigated

SSE

0-5-10-15 5 10 15

15

5

-5

-15

Galena

Sphalerite

Distance from fault in metres

0-5-10-15 5 10 15

15

5

-5

-15

34S

Texture-based laser S isotope analyses defines feeder faults

>3m into hanging wall, bacteriogenic S dominates.

Even minor faults, with early limited movement allow flow

HydrothermalHydrogeology

0

5

10

15

Frequency

-30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30

Galena

0

5

10

15

Frequency

-30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30

Sphalerite

34S

Bulk S Studies - Each sample represents up to ONE MILLION TONNES of ORE

Bulk S Studies 5 LENS - representing ~70% of ore at Navan (so far!)

>90% of sulphide is from BACTERIOGENIC source!

Frequency distribution of minor hydrothermal S source skewed by ease of sampling, and vice versa.

0

5

10

Frequency

-30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30

All Concentrates

Zn Concentrate

Pb Concentrate

No Bugs

No Economic Ore Deposit

Message from that S isotope study?