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PESA Qld Breakfast 22 May 2014. Shale oil – what does it take?. David Lowry. www.lowryresources.com.au. Source rock issues: Total Organic Carbon Hydrogen Index Maturity Kinetics Thickness Porosity Fraccing Issues Poissons Ratio, Youngs Modulus Reservoir/seal couplets
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PESA Qld Breakfast 22 May 2014 Shale oil – what does it take? David Lowry www.lowryresources.com.au
Source rock issues: Total Organic Carbon Hydrogen Index Maturity Kinetics Thickness Porosity Fraccing Issues Poissons Ratio, Youngs Modulus Reservoir/seal couplets Resource Estimates Exploration in Australia
Source rock issues: Need a good source rock Initial Total Organic Carbon > 4% Initial Hydrogen Index > 400 (my impression) Obtain from RockEval pyrolysis. Preferably core, or at least hand-picked cuttings. Regular cuttings likely to be full of cavings and may steer you away from a good source rock
Source rock issues: Need a rich source rock Initial Total Organic Carbon > 4% Initial Hydrogen Index > 400 (my impression) mg HC generated from 1 g Organic Carbon at full maturity 1000 mg Organic Carbon ~ 1200 mg kerogen Immature Fully mature 600 mg Oil & Gas
Source rock issues: Need a rich anoxic source rock Pyrite Lamination (no bioturbation) Good preservation of organic matter because no scavengers (my impression) Immature Fully mature
Source rock issues: Need a rich mature source rock Maturity 0.8% — 1.1% Ro Estimating maturity Vitrinite reflectance – traditional but very likely suppressed in oil-prone shale. VIRF or FAMM - good TMax from RockEval – good for Proterozoic rocks; but suppression Modelling – good if heat flow and stripping histories are known; good for mapping; can use old wells but need some calibration.
Source rock issues: Need to know your kerogen kinetics How easily does your kerogen crack? Track change in oil/gas ratio with maturity Use A and E parameters to model maturity
Source rock issues: Thickness Thickness: the thicker the better. Minimum 30 m? volumetrics; engineering; seismic
Source rock issues: Porosity SEM with ion milling Porosity: Organic porosity important at Ro ~1% Generation can also fracc the shale, giving permeability
Source rock issues: Porosity Jarvie ,2012 10% TR 80% TR 0% 14%
Fraccing Issues Poissons Ratio, Youngs Modulus Reservoir/source couplets clay rich, ductile cemented by silica, calcite or dolomite. Good to fracc Slatt, 2013 Optimum: interbedded reservoir/source ouplets
Oil generated= Thickness (m) x initial TOC x initial Hydrogen Index x Transformation Ratio
Available Oil in place = Thickness (m) x initial TOC x initial Hydrogen Index x Transformation Ratio — Adsorbed oil — Migrated oil Recoverable oil x Recovery factor
Resource Estimates Resource calculation TOC. In anoxic marine source rock, uranium is adsorbed on the organic matter. Gamma Ray log roughly proportional to TOC Image deleted; data not yet open file Cluff, 2012
Problem of adsorption Kerogen adsorbs early-formed oil. Not available for migration into pores and fractures Pepper & Corvie (1995) estimate: 100 mg oil / g organic C Suppose HI source rock is 500 and take particular Ro/TR kinetics curve. At Transformation Ratio 0.2, kerogen will have generated 500 x 0.2 = 100 mg oil / g TOC Just at start of expulsion at Ro 0.84%
To quantify expulsion, need to quantify kinetics and initial HI Image deleted; data not yet open file
Recovery Factors for shale oil Look to US experience Evaluating production potential of mature us oil, gas shale plays. Oil & Gas Journal 12/03/2012
Recovery Factors for shale oil Oil & Gas Journal 12/03/2012 US Energy Information Administration 2013. Based on U.S. shale production experience, ...... the recovery factors for shale oil range from 3 percent to 7 percent of the oil in-place with exceptional cases being as high as 10 percent or as low as 1 percent. http://www.eia.gov/analysis/studies/worldshalegas/
Recovery Factors for shale oil Oil & Gas Journal 12/03/2012
Recovery Factors for shale oil Oil & Gas Journal 12/03/2012
Study the core as source Rock Eval, RockEval on extracted samples, extract GCMS; Py-GC, Bulk and MSSV multicomponent kinetics, FAMM or VIRF, SEM with ion milling, clay XRD. Study the core as reservoir Mechanical properties, helium porosity, MICP, % carbonate, Dean-Starke saturation; dipole sonic log, image log A lot more science is needed than in conventional exploration. Companies will need staff with strong skills in the theory and practice of geochemistry and rock mechanics.
Australia Shale oil: McArthur Basin Barney Creek Fm (1.6 Ga) & Velkerri Fm (1.4 Ga)
Barney Creek Fm Velkerri FM HI 1000 Tmax Crick et al., 1988
Who are the players? Permits held/applied for by Armour Energy Southern McArthur Basin Northern Georgina Basin
Falcon O&G Beetaloo Sub-basin.
No obvious burial since Cambrian; chance of overpresssuring is limited Law et al., 2010
2011 Shenadoah-1 flowed wet gas from Velkerrie Relatively simple structure; source rocks in both gas and oil window
Baldwin-2Hst1 August 2011 875 m in Arthur Creek Hot Shale. Oct 2012 fracc; casing failed Owen-3H August 2011 966 m in Arthur Creek Hot Shale. Oct 2012 10 stage fracc; recovered fracc fluids but no hydrocarbons MacIntyre-2H June 2012 1080 m in Arthur Creek Hot Shale. Oct 2012 9 stage fracc. Testing suspended (H2S)
Buru Energy is major player in Canning Basin Ordovician Goldwyer Fm recognised as major shale oil opportunity
SW NE
New Standard Energy holds a large area New Standard Energy
X X Hess – formerly Kingsway X
Perth Basin. Hovea Mbr of Kockatea Shale (Earliest Triassic)
AWE active exploration for tight gas. Four vertical wells stimulated. Arrowsmith-2 5 stage fracc. 22 bbl
Eromanga Basin. Toolebuc Shale Early Cretaceous
Exoma & CNOOC drilled a dozen wells on the Maneroo Platform. Maturity not quite high enough Elsewhere Toolebuc is largely immature; need to find an area with high heat flow and deep maximum burial
PESA Qld Breakfast 22 May 2014 Shale oil – what does it take? Exceptional geology; lots of money David Lowry www.lowryresources.com.au