Grant agreement No ShaleXenvironmenT. Maximizing the EU shale gas potential by minimizing its environmental footprint

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1 Grant agreement No ShaleXenvironmenT Maximizing the EU shale gas potential by minimizing its environmental footprint H2020-LCE Competitive low-carbon energy D2.1 Report on PTx properties of shale rock samples WP 2 Shale Core Acquisition and HTHP Handling Capabilities Due date of deliverable 28/02/2018 (Month 30) Actual submission date 03/05/2018 (Month 33) Start date of project September 1 st 2015 Duration Lead beneficiary Last editor Contributors Dissemination level 36 months Halliburton Jabraan Ahmed (UCL) UCL, Halliburton, GFZ, UoM Public (PU) This Project has received funding from the European Union s Horizon 2020 research and innovation programme under grant agreement no

2 History of the changes Version Date Released by Comments Jabraan Ahmed First draft circulated internally to WP2 members Jabraan Ahmed Second draft circulated internally to WP2 members Jabraan Ahmed Final Draft Jabraan Ahmed Submission Version Table of contents History of the changes... 2 Key word list... 3 Definitions and acronyms Introduction General context Deliverable objectives Methodology Compositional Data PT Conditions Summary of activities and research findings Composition Data HPHT Data & Handling Capabilities Conclusions and future steps Publications resulting from the work described Bibliographical references List of tables Table 2.1 Experimental techniques used in the determination of composition parameters. XRD - X- ray diffraction, QemScan - quantitative evaluation of minerals by scanning, EDS energy dispersive spectroctrscopy, ICP inductively coupled plasma, MS mass spectrometry, AES - atomic emission spectroscopy, OES - optical emission spectrometry and SEM scanning electron microscopy Table 3.1 Interpretations of compositional data detailed in table Table 3.2 Compositional data of Bowland Shale Samples as conducted by SXT members. (References given in 5) Compositional parameters are given in wt% PU Page 2 of 13 Version 1.3

3 Key word list Shale rock library, European shale gas basins, Pressure Temperature conditions, Shale Composition, Total organic carbon range, Maturity range, Exploration target areas Definitions and acronyms Acronyms BGS BSF D EIA HB HPHT MPa OM PTx Ro SXT Tcf Definitions British Geological Survey Bowland Shale Formation Deliverable U.S. Energy Information Administration Halliburton High Pressure High Temperature Mega pascal (pressure) Organic Matter Pressure temperature composition Vitrinite reflectance (%); measure of thermal maturity ShaleXenvironmenT European Consortium Trillion cubic feet (for gas reservoir estimates) TOC Total organic carbon, measured in volume percent (%) UCL USGS WP University College London United States Geological Survey Work Package PU Page 3 of 13 Version 1.3

4 1. Introduction 1.1 General context WP2 has the main task of providing shale core samples for experimental characterization. The specific objectives as part of WP2 include: 1. Provide shale rock samples (some at reservoir pressure) for scientific research. 2. Develop capability for laboratory exchange and analysis of pressurised samples recovered from depth. 3. Provide pressure, temperature & composition (PTx) properties of shale rocks to be used in physical, chemical, thermodynamic models and mechanical experiments. 1.2 Deliverable objectives This deliverable (D2.1) focusses on the latter objective by summarising PTx data on shale rock samples which have either been determined experimentally by consortium partners, or derived from the literature. Due to the nature of the data presented herein, there is some overlap in content between the deliverables of WP2. However, D2.2 and D2.3 are more generalised in their nature and report insitu reservoir conditions of shale gas bearing basins across Europe. Within this report, we focus on: Providing compositional data on shale rock samples including: bulk mineralogy, clay mineralogy, elemental geochemistry, total organic carbon (TOC), organic matter (OM) composition/type/maturity and porosity. The development of high pressure high temperature (HPHT) Laboratory handling capabilities and results of HPHT experiments. In addition to PTx data being invaluable in its own right, these measurements form the basis parameters input into experiments, technical analyses and models covered by the SXT research consortium. PU Page 4 of 13 Version 1.3

5 2. Methodology 2.1 Compositional Data Due to the myriad of variables involved in resource characterisation, the consortium has focussed its efforts by considering one prospective shale-gas play in particular: the Bowland Shale Formation (BSF) located in Lancashire, N.England. Thus, we report the compositional properties of the BSF in detail herein and summaries for other European basins can be found in D2.2 and D2.3 (month 36). The experimental techniques used to determine the compositional parameters are given in table 2.1. Details regarding the instrumentation of each procedure are beyond the scope of this report and the reader is referred to the journal articles ( 6.) where they are discussed in depth. Table 2.1 Experimental techniques used in the determination of composition parameters. XRD - X- ray diffraction, QemScan - quantitative evaluation of minerals by scanning, EDS energy dispersive spectroctrscopy, ICP inductively coupled plasma, MS mass spectrometry, AES - atomic emission spectroscopy, OES - optical emission spectrometry and SEM scanning electron microscopy. x Parameter Technique Bulk Mineralogy XRD + QemScan Clay Mineralogy Oriented >2μm + heating Elemental Geochemistry QemScan + EDS + ICP- MS/AES/OES Maturity RE + Vitrinite Reflectance TOC RE+ LECO OM composition RE + δ 13 C Porosity SEM + QemScan + Gas Pycnometry + Permeametry PU Page 5 of 13 Version 1.3

6 2.2 PT Conditions PT conditions of prospective European shale gas basins from literature data are discussed in D2.2 and will be augmented in D2.3 (month 36). Development of insitu HPHT measurement and handling capabilities are discussed in 3. PU Page 6 of 13 Version 1.3

7 3. Summary of activities and research findings 3.1 Composition Data A summary of composition data derived from experimental works and literature are given below: Table 3.1 Interpretations of compositional data detailed in table 3.2. x Parameter Bulk Mineralogy Clay Mineralogy Findings Generally low clay contents (<20%) with the lower part of the formation being carbonate rich whilst the upper part switches to being dominated by quartz. Presence of framboidal pyrite is indicative of deposition in an environment persistently depleted in oxygen. Mg-rich carbonate phases (ankerite-dolomite etc) indicative of significant diagenetic alterations having taken place post-burial Kaolinite and Illite are the dominant clay minerals. The lack of a 2:1 structured expanding clay (i.e. smectite) is favourable from a hydraulic fracturing perspective. Elemental Geochemistry Maturity QemScan analyses correlate well with XRD data where BSF has a grain size in excess of 10 microns. Redox proxies indicating high degrees of anoxia correlate well with high TOC intervals. Zr and Ti correlate well with detrial quartz and thus are a good indicator of detrital influx into the Bowland Basin. The BSF has been buried and uplifted asymmetrically, like many US shales. Burial was most severe in the West as evidenced in the PH1 borehole where maturities are well into the gas window (Tmax ~485 C) Time equivalent sections from the basin East are marginally less mature (Tmax ~450 C) however they have been uplifted to the surface. From the literature, the BSF has been shown to be highly mature in wells further south (ie. Formby) PU Page 7 of 13 Version 1.3

8 TOC OM composition Porosity TOC is highly variable but correlates reasonably well with proposed sea-level curves. TOC is highest (~5 wt%) in the locally termed marine bands intervals which were deposited at times of high sea-level. However, non-marine band sections of the BSF can also show elevated TOC contents, the geological controls on this are currently unknown. One theory is that this OM has a terrestrial source (type III) and so despite being abundant, is of a lower quality. The BSF is dominated by type II/III OM. Marine band intervals have δ 13 C values of ~-27.9 which is indicative of a predominately marine type II source (much more favourable for hydrocarbon generation) Non-marine band intervals have more type III OM (less conducive to hydrocarbon generation) however the proportions of type II/III in this strata have yet to be quantified. Low hydrogen indices indicate some hydrocarbon expulsion from the source rock. This may also be an issue of sample preparation procedures however. Total and effective porosities are highly variable. Average values from gas pycnometry experiments indicate values ~4 and 2 % respectively. Permeability + Compressibility This work is ongoing, preliminary experiments suggest permeabilities in the range of to m 2 at ambient pressures. One experiment conducted at reservoir pressures saw effective porosity in a BSF from the PH1 well sample drop from 4 to 2.5 %. PU Page 8 of 13 Version 1.3

9 Table 3.2 Compositional data of Bowland Shale Samples as conducted by SXT members. (References given in 5) Compositional parameters are given in wt%. UCL_SXT sample code sample no. Quartz Feldspar Calite Ankerite Pyrite Muscovite SXT1_BS_15 B SXT1_BS_ SXT2_BS_30 NB_05 SXT1_BS_02 2 SXT1_BS_ SXT1_BS_04 4 SXT1_BS_16 B SXT1_BS_05 5 SXT1_BS_17 B SXT1_BS_18 B Preese Hall- 1 SXT1_BS_06 6 SXT1_BS_07 7 SXT2_BS_33 NB_08 SXT1_BS_19 B SXT1_BS_20 B SXT1_BS_ SXT1_BS_21 B SXT1_BS_22 B SXT1_BS_23 B SXT1_BS_24 B SXT1_BS_25 B SXT1_BS_ SXT1_BS_11 11 SXT1_BS_13 13 SXT1_BS_ Marl Hill Moor MHD13 SXT2_BS_38 SXT2_BS_39 SXT2_BS_41 SXT2_BS_42 SXT2_BS_43 SXT2_BS_46 NB_13 NB_14 NB_16 NB_17 NB_18 NB_21 Blue Scar Walmsley Bridge SXT3_BS_59 SXT3_BS_60 SXT3_BS_61 SXT3_BS_65 BF04 BF05 BF06 BF10 PU Page 9 of 13 Version 1.3

10 UCL_SXT sample code sample no. Chlorite Kaolinite Illite Smectite Clays (unclassified) TOC (wt%) SXT1_BS_15 B SXT1_BS_ SXT2_BS_30 NB_05 SXT1_BS_ SXT1_BS_ SXT1_BS_ SXT1_BS_16 B SXT1_BS_ SXT1_BS_17 B SXT1_BS_18 B Preese Hall-1 SXT1_BS_ SXT1_BS_ SXT2_BS_33 NB_08 SXT1_BS_19 B SXT1_BS_20 B SXT1_BS_ SXT1_BS_21 B SXT1_BS_22 B SXT1_BS_23 B SXT1_BS_24 B SXT1_BS_25 B SXT1_BS_ SXT1_BS_ SXT1_BS_ SXT1_BS_ Marl Hill Moor MHD13 SXT2_BS_38 SXT2_BS_39 SXT2_BS_41 SXT2_BS_42 SXT2_BS_43 SXT2_BS_46 NB_13 NB_14 NB_16 NB_17 NB_18 NB_21 SXT3_BS_59 BF Blue Scar Walmsley Bridge SXT3_BS_60 BF SXT3_BS_61 BF SXT3_BS_65 BF PU Page 10 of 13 Version 1.3

11 UCL_SXT sample code sample no. Qtz + Fsp + Py Normalisd Ternary wt% Clay content Carbonates SXT1_BS_15 B SXT1_BS_ Permeability (m 2 ) Nanodarcy (nd) SXT2_BS_30 NB_05 2.0E SXT1_BS_02 2 SXT1_BS_ SXT1_BS_04 4 SXT1_BS_16 B SXT1_BS_05 5 SXT1_BS_17 B SXT1_BS_18 B Preese Hall- 1 SXT1_BS_06 6 SXT1_BS_07 7 SXT2_BS_33 NB_08 2.5E SXT1_BS_19 B SXT1_BS_20 B SXT1_BS_ SXT1_BS_21 B E SXT1_BS_22 B SXT1_BS_23 B SXT1_BS_24 B SXT1_BS_25 B SXT1_BS_ SXT1_BS_11 11 SXT1_BS_13 13 SXT1_BS_ Marl Hill Moor MHD13 SXT2_BS_38 SXT2_BS_39 SXT2_BS_41 SXT2_BS_42 SXT2_BS_43 SXT2_BS_46 NB_13 NB_14 NB_16 NB_17 NB_18 NB_21 PU Page 11 of 13 Version 1.3

12 3.2 HPHT Data & Handling Capabilities Efforts toward acquiring insitu measurements and downhole sub-sample are ongoing. UCL and Halliburton are currently seeking suitable locations to deploy the novel CoreVault technology whereby samples can be taken and held at reservoir conditions. We are in current discussions with various operators (Eni, igas, Cuadrilla) regarding a trial of CoreVault in a European test borehole with meetings planned in June/July. Developments of HPHT laboratory handling capability have been made in the meantime, which will allow for UCL Earth Science laboratories to be able to receive and load pressurised samples into pre-existing rock deformation apparatus. These designs do require some further refinement and will be revisited once confirmation of a test-site is finalised. HPHT experiments are currently being conducted on BSF samples from the SXT rock library to measure for mechanical and petrophysical properties. The aim of this study is to compare the differences between borehole and outcrop material sampling the same geological intervals. Ultimately, once combined with data from CoreVault samples, comparisons and bestpractices can be suggested for shale-play characterisation. Furthermore, these results can be used to tie into the modelling and experimental efforts of the other consortium members. 4. Conclusions and future steps The BSF has been compositionally characterised and the data disseminated to the various consortium members to facilitate their experimental and modelling works. The majority of this data is summarised in table 3.1 and the raw values given in table 3.2. UCL are currently conducting further compositional analyses which will be made available in a similar fashion. Developments have been made in the acquisition and processing of HPHT shale-core samples. We hope for positive discussions with oil and gas operators in the coming months for the deployment of CoreVault and additionally, will disseminate the results of any HPHT tests (ongoing) before the project end in August Publications resulting from the work described Fauchille, Ma, Rutter, Chandler, Lee & Taylor (2017). An enhanced understanding of the Basinal Bowland shale in Lancashire (UK), through microtextural and mineralogical observations. Marine and Petroleum Geology. 86. p Herrmann et al. (submitted 2018 pending review). Ahmed, Mitchell & Jones. Petrophysical and mechanical comparisons between Borehole and Outcrop material sampling time-equivalent mudstones deposits from the Bowland Basin. (ongoing expected submission 08/18) PU Page 12 of 13 Version 1.3

13 6. Bibliographical references 1. Ahmed, Thurow, Meredith, Wood, Jourdan & Jones. (in prep) Lateral heterogeneity of the Bowland Shale Formation, Carboniferous, UK. 2. Ahmed, Thurow, Meredith, Mitchell & Jones. (in prep) Petrophysical Properties of the Bowland Shale Formation. 3. Andrews (2013). The Carboniferous Bowland Shale gas study: geology and resource estimation. British Geological Survey for Department of Energy and Climate Change. 4. Clarke, Bustin & Turner (2014). Unlocking the Resource Potential of the Bowland Basin, NW England. 5. Emmings, Davies, Vane, Leng, Moss-Hayes, Stephenson & Jenkin (2017). Stream and slope weathering effects on organic-rich mudstone geochemistry and implications for hydrocarbon source rock assessment: A Bowland Shale case study. Chemical Geology p Fauchille, Ma, Rutter, Chandler, Lee & Taylor (2017). An enhanced understanding of the Basinal Bowland shale in Lancashire (UK), through microtextural and mineralogical observations. Marine and Petroleum Geology. 86. p Gawthorpe (1987). Tectono-sedimentary evolution of the Bowland Basin, N England, during the Dinantian. Journal of the Geological Society of London. 144 (1). p Hough, Vane, Smith & Moss-Hayes (2014). The Bowland Shale in the Roosecote Borehole of the Lancaster Fells Sub-Basin, Craven Basin, UK: A Potential UK Shale gas Play? DOI / MS 9. Slatt & Rodriguez (2012). Comparative sequence stratigraphy and organic geochemistry of gas shales: Commonality or coincidence? Journal of Natural Gas Science and Engineering. 8. p Smith, Turner & Williams (2012). UK data and analysis for shale gas prospectivity. Geological Society, London, Petroleum Geology Conference series. 7 (1). 11. Smith, Vane, Moss-Hayes & Andrews (2012). Rock-Eval geochemical analysis of 109 samples from the Carboniferous of the Pennine Basin, including the Bowland-Hodder unit. Appendix B to DECC final report (Andrews, 2013). p.8. PU Page 13 of 13 Version 1.3