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Basin-Specific Geochemistry to Promote Unconventional Efficiency
Project Number
FWP 100211
Last Reviewed Dated
Performer(s)

SLAC National Accelerator Laboratory

Background
https://mm2.netl.doe.gov/Image%20Library/technologies/oil-gas/publications/100211-Pic.jpg
Schematic illustration of fracture system across length scales. Top panel: Following stimulation, fluids are more acidic and reactive in the periphery of the fracture network. Barium and other constituents leached from mud by acid in the wellbore environment and transported into fractures can drive mineral scale precipitation. Middle and bottom panels: Mineral scale precipitation occludes porosity in fractures and in shale matrix, attenuating permeability and production. Bottom: matrix abutting fractures, through which gas and oil must flow to be produced, is most strongly impacted by acid attack, which creates secondary porosity, and by scale precipitation. This important region is referred to herein as the “altered zone”.

Project Description

During stimulation, shale porosity can be initially enhanced when injected concentrated acid imbibes into fracture surfaces and dissolves minerals, promoting the opening secondary porosity and widening of micro-fractures. This near-surface “altered zone” is the main conduit through which oil and gas flow out of matrix. The thickness and permeability of this altered zone are therefore extremely important to improving recovery from matrix. During shut-in, mineral dissolution increases both the pH and salinity of the solution. As the pH of brine increases, scale precipitation becomes favorable, and permeability can drop below that of unreacted shale. Our previous research shows that the extent and rates of scale precipitation in shale matrix are dependent on shale composition, in addition to the types and concentrations of drilling mud and acid used during stimulation. Thus, the key to scale mitigation lies in optimizing fluid compositions and injection practices. Moreover, we have observed that fluid and gas exchange into/out of shale matrix is strongly enhanced by micro-fractures and the development of secondary porosity. These observations point a way to improving recovery from matrix by manipulating chemical reactions to promote mineral dissolution while simultaneously controlling scale precipitation.

Shale compositions and stimulation practices vary substantially between basins, while showing intra-basin similarities. Stimulation practices, and particularly fluid chemistry, not only vary in the total number of chemicals used but also in the type of chemical used for a specific purpose (friction reducer, corrosion inhibitor, anti-scaling, etc.). These variations necessitate a focus on basin-specific parameters to more deeply understand chemical controls over scale precipitation and to understand intra-region variability, crucial to improving efficiency/recovery factor.

This project is focusing on two strategic geochemistry-based research thrusts where new knowledge can immediately begin to improve unconventional gas and oil recovery factors. First, we are evaluating mineral scale precipitation processes specific to major shale formations and fracture stimulation practices and developing geochemistry-based approaches to mitigate it. This knowledge has an additional benefit of improving our ability to reuse flowback and produced water without causing formation damage. The focus of this work will be to compare and contrast conditions specific to Marcellus (dry gas) and Midland (oil) basins. We are also conducting research to understand how geochemistry can be used to manipulate the thickness and permeability of the altered zone by focusing on controlling microscale chemical and mechanical features such as secondary porosity created during stimulation, the connectivity of this porosity across the altered zone, and irreversible mineral scale precipitation within the altered zone. Our ultimate goal is to develop approaches to manipulate the thickness and permeability of the altered zone during stimulation to increase access to matrix and thus production recovery factors.

To monitor scale precipitation and microstructure evolution within shales, we are using a combination of laboratory, synchrotron X-ray imaging, computed tomography, electron microscopy, and seismic techniques. Research is being performed in consultation with industrial experts to help facilitate technology transfer from the laboratory to the field.

Impact

Project Benefits

The fundamental geochemical-microstructural knowledge being developed by this project is helping to improve the efficiency and environmental impact of unconventional stimulation practices. Our ultimate goal is to develop approaches to manipulate the thickness and permeability of the altered zone during stimulation to increase access to matrix and thus production recovery factors. These improvements are helping to advance the DOE-FE mission of improving hydrocarbon long-term recovery, reducing environmental impact, and helping the U.S. to establish energy dominance.

Additional Information

Patents

  1. Patent (2019) - Fracture Fluid Alteration to Mitigate Barite Scale Precipitation in Unconventional Oil/Gas Shale Systems. Patent ID: 16/519823

Manuscripts published, submitted, or in revision

  1. Gundogar, A.S.; Ross, C.M.; Jew, A.D.; Bargar, J.R.; Kovscek, A.R. Multiscale Investigation of Secondary Mineral Precipitation in Fractured Shales through Reactive Core-Flood Experiments, November 2020 Energies Special Issues. 2020. Submitted.
  2. Li, Q.; Wang, L.; Perzan, Z.; Caers, J.; Brown, G.E. Jr.; Bargar, J.R.; Maher, K. Global Sensitivity Analysis of a Reactive Transport Model for Mineral Scale Formation During Hydraulic Fracturing. Environmental Engineering Science. 2020. In review.
  3. Jew, A. D.; Bargar, J. R.; Brownlow, J., Strontium behavior in midland basin unconventional reservoirs: the importance of base fluids. Extended abstract of the Unconventional Resources Technology Conference: July 20-22, Austin, TX, 2020. DOI: 10.15530/urtec-2020-3016
  4. Li, Q.; Jew, A. D.; Brown, G. E. Jr.; Bargar, J. R.; Maher, K., Reactive transport modeling of shale-fluid interactions after imbibition of fracturing fluids. Energy and Fuels, 34 (5), 5511-5523, 2020.
  5. Ding, J.; Clark, A. C.; Vanorio, T.; Jew, A. D.; Bargar, J. R., Acoustic velocity signatures of acidized and propped fractures in Marcellus shale. Extended abstract for the SEG conference, pp 2434-2438, 2020.
  6. Jew, A. D.; Besançon, C. J.; Roycroft, S. J.; Noel, V. S.; Bargar, J. R.; Brown, G. E., Chemical speciation and stability of uranium in unconventional shales: impact of hydraulic fracture fluid. Environmental Science & Technology, 54 (12), 7320-7329, 2020.
  7. Gundogar, A. S.; Ross, C. M.; Li, Q.; Jew, A. D.; Bargar, J. R.; Kovscek, A. R., Multiscale imaging of core flooding experiments during transport of reactive fluids in fractured unconventional shales. Extended abstract for the 2020 SPE Western Regional Meeting, April 27–30, Bakersfield, CA. Accepted and decided to postpone to a later date, 2020
  8. Ding, J.; Clark, A. C.; Vanorio, T.; Jew, A. D.; Bargar, J. R., Time-lapse acoustic monitoring of fracture alteration in Marcellus shale. Extended abstract of the Unconventional Resources Technology Conference, July 20-22, Austin, TX, 2020. DOI: 10.15530/urtec-2020-2956
  9. Ding, J.; Mighani, S.; Clark, A. C.; Vanorio, T., Monitoring chemo-mechanical fracture behavior through engineering geophysics experiments. Extended abstract for the 82nd EAGE Conference & Exhibition, December 8-11, Amsterdam, Netherlands. 2020, pp 1-5. DOI: 10.3997/2214-4609.202011181
  10. Jew, A. D.; Li, Q.; Cercone, D.; Brown, G.E. Jr.; Bargar, J. R., A new approach to controlling barite scaling in unconventional systems. URTEC-512-MS. Extended Abstracts of the Unconventional Resources Technology Conference: Denver, Colorado, USA 2019. DOI 10.15530/urtec-2019-512.
  11. Li, Q.; Jew, A. D.; Kohli, A.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R., Thicknesses of chemically altered zones in shale matrices resulting from Interactions with hydraulic fracturing fluid. Energy & Fuels 2019, 33 (8), 6878-6889.
  12. Li, Q.; Jew, A.; Cercone, D.; Bargar, J.; Brown, G. E. Jr.; Maher, K., Geochemical modeling of iron (hydr)oxide scale formation during hydraulic fracturing operations. Extended Abstracts of the Unconventional Resources Technology Conference: Denver, Colorado, USA 2019, p 14. DOI: 10.15530/urtec-2019-612.
  13. Jew, A. D.; Li, Q.; Cercone, D.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R., Barium sources in hydraulic fracturing systems and chemical controls on its release Into solution. Extended Abstracts of the Unconventional Resources Technology Conference, July 23-25, Houston, Texas, USA 2018, p 12. DOI: 10.15530/URTEC-2018-2899671.
  14. Li, Q.; Jew, A. D.; Kiss, A. M.; Kohli, A.; Alalli, A.; Kovscek, A. R.; Zoback, M. D.; Cercone, D.; Maher, K.; Brown, G. E., Jr.; Bargar, J. R., Imaging pyrite oxidation and barite precipitation in gas and oil shales. Extended Abstracts of the Unconventional Resources Technology Conference, July 23-15, Houston, Texas, USA 2018, p 10. DOI: 10.15530/URTEC-2018-2902747.
  15. Alalli, A.; Li, Q.; Jew, A.; Kohli, A.; Bargar, J.; Zoback, M.; Kovscek, A., Effects of hydraulic fracturing fluid chemistry on shale matrix permeability. Extended Abstracts of the Unconventional Resources Technology Conference, July 23-25, Houston, Texas, USA 2018, p 10. DOI: 10.15530/URTEC-2018-2881314.
  16. Dustin, M. K.; Bargar, J. R.; Jew, A. D.; Harrison, A. L.; Joe-Wong, C.; Thomas, D. L.; Brown, G. E.Jr.; Maher, K., Shale kerogen: hydraulic fracturing fluid interactions and contaminant release. Energy & Fuels 2018, 32 (9), 8966-8977.
  17. Jew, A. D.; Harrison, A. L.; Kiss, A. M.; Dustin, M. K.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Cercone, D.; Bargar, J. R., Mineralogical and physical changes that control pore-scale shale-gas properties. Extended Abstracts of the Unconventional Resources Technology Conference, July 24-26, Austin, Texas, USA 2017, p 7. DOI: 10.15530/urtec-2017-2708858
  18. Jew, A. D.; Dustin, M. K.; Harrison, A. L.; Joe-Wong, C. M.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R., Impact of organics and carbonates on the oxidation and precipitation of iron during hydraulic fracturing of shale. Energy & Fuels 2017, 31 (4), 3643-3658.
  19. Harrison, A.; Jew, A.; Dustin, M.; Thomas, D.; Joe-Wong, C.; Bargar, J. R.; Johnson, N.; Brown, G. E. Jr.; Maher, K., Element release and reaction-induced porosity alteration during shale-hydraulic fracturing fluid interactions. Applied Geochemistry 2017, 82.
  20. Kiss, A.; Jew, A.; Joe-Wong, C.; Maher, K.; Liu, Y.; Brown, G.; Bargar, J., Synchrotron-based transmission x-ray microscopy for improved extraction in shale during hydraulic fracturing. SPIE: Optical Engineering + Applications, 2015; Vol. 9592.

Invited Presentations at National Meetings

  1. Gundogar, A.S.; Ross, C.M.; Li, Q.; Jew, A.D.; Bargar, J.R.; Kovscek, A.R. Multiscale imaging of core flooding experiments during transport of reactive fluids in fractured unconventional shales, 2020 SPE Western Regional Meeting, Bakersfield, CA (Manuscript submitted on March 5, 2020) [Invited].
  2. Jew, A.D. (2020) Field Laboratories: A Data Driven Approach for Basin Specific Research. Presented at the Unconventional Resources Technology Conference. Austin, TX. Jul 19-22. [Invited]
  3. Druhan, J. L.; Ling, B.; Davila, G.; Battiato, I. (2019) Imaging the reactive transport properties of sedimentary formations across scales. Presented at the AGU Fall Meeting. Dec 9-13, San Francisco, CA. [Invited]
  4. Noël, V.; Fan, W.; Druhan, J.; Jew, A. D.; Li, Q.; Kovscek, A.; Brown, G. E. Jr.; Bargar, J. R. (2019) X-ray imaging of tracer reactive transport in unconventional shales. Presented at the CMC-UF all hands meeting, Stanford University. Oct 24. Palo Alto, CA. [Invited]
  5. Jew, A. D.; Li, Q.; Cercone, D.; Brown, G. E. Jr.; Bargar, J. R. (2019) A New approach to controlling barium scaling in unconventional systems. Presented at the Unconventional Resources Technology Conference (URTeC). Apr. 22. Pittsburgh, PA. [Invited]
  6. Bargar, J. R.; Jew, A. D.; Harrison, A. L.; Kiss, A.; Kohli, A.; Li, Q.; Maher, K.; Brown, G. E. Jr. (2017) Geochemistry of shale-fluid reactions at pore and fracture scales. Presented at the Goldschmidt Geochemistry conference. Aug 16. [Invited]
  7. Bargar, J. R.; Kiss, A.; Kohli, A.; Harrison, A. L.; Jew, A. D.; Dustin, M.; Joe-Wong, C.; Maher, K.; Brown, G. E. Jr.; Zoback, M.; Liu, Y.; Cercone, D. (2016) Geochemistry of shale-fluid reactions at pore and fracture scales. Presented at the 252nd American Chemical Society National Meeting. Aug 21. [Invited]
  8. Bargar, J. R.; Brown, G. E. Jr.; Dustin, M. K.; Harrison, A. L.; Jew, A. D.; Joe-Wong, C.M.; Maher, K. (2015) Geochemical control of shale fracture and matrix permeability. Presented at the Shales without Scales Workshop. Santa Fe, USA. June 10. [Invited]
  9. Bargar, J. R.; Brown, G. E. Jr.; Dustin, M. K.; Harrison, A. L.; Jew, A. D.; Joe-Wong, C.M.; Maher, K. (2015) Geochemical control of shale fracture and matrix permeability. Presented at Baker Hughes Incorporated, Tomball, USA, July 14. [Invited]

Talks and Posters Presented at National Meetings.

  1. Jew, Adam D.; Spielman-Sun, Eleanor; Li, Qingyun; Ding, Jihui; Gundogar, Asli; Vanorio, Tiziana; Clark, Anthony; Brown, Gordon E., Jr.; Bargar, John R. Impact of Geochemistry on Unconventional Shale Efficiency and Mineral Scale Production: Clay-rich versus Carbonate-rich Shales. Clay Mineral Society Pacific Northwest National Laboratory Richland, WA October 18-23, 2020.
  2. Bargar, John R., Basin-specific geochemistry to promote unconventional efficiency. DOE-FE Office of Oil and Natural Gas Fundamental Research Project Review Virtual Meeting, Pittsburgh, PA, Oct 16, 2020. [Oral]
  3. Spielman-Sun, Eleanor; Jew, Adam D.; Bargar, John R. (2020) The impact of acid-base stimulation sequence on mineral stability for tight/impermeable unconventional rocks: Delaware Basin case study. Presented at the Stanford Synchrotron Radiation Lightsource (SSRL) Users’ Meeting. Sept. 28-Oct. 9, 2020. [Poster]
  4. Jew, Adam D.; Bargar, John R.; Brownlow, Josh; Laughland, Matt (2020) The Importance of Base Fluids for Water Management in Unconventional Reservoirs. Presented at the Stanford Synchrotron Radiation Lightsource (SSRL) Users’ Meeting. Sept. 28-Oct. 9, 2020. [Poster]
  5. Ding, J.; Clark, A. C.; Vanorio, T.; Jew, A. D.; Bargar, J. R. (2020) Time-lapse acoustic monitoring of fracture alteration in Marcellus shale. Presented at the Unconventional Resources Technology Conference. Austin, TX. Jul 19-22. [Oral]
  6. Jew, A.D.; Bargar, J.R.; Brownlow, J.; Laughland, M. (2020) Strontium behavior in Midland Basin unconventional reservoirs: the importance of base fluids. Presented at the Unconventional Resources Technology Conference. Austin, TX. Jul 19-22. [Oral]
  7. Bargar, John R.(2020), Basin-specific geochemistry to promote unconventional efficiency. DOE-FE Office of Oil and Natural Gas Fundamental Shale Research Program Virtual Briefing, July 14. [Oral]
  8. Gundogar, A.S.; Ross, C.M.; Jew, A.D.; Bargar, J.R.; Kovscek, A.R. (2020) Multiscale Imaging of Reactive Fluid Transport in Fractured Shales. Presented at the SUPRI-A Annual Affiliates Meeting. Stanford, CA. June 11 [Oral].
  9. Gundogar, A.S.; Ross, C.M.; Li, Q.; Jew, A.D.; Bargar, J.R.; Kovscek, A.R. (2019) Multiscale imaging characterization of fracture fluid migration and reactive transport in shales. Presented at the AGU Fall Meeting. San Francisco, CA. Dec 9-13. [Poster]
  10. Noël, V.; Fan, W.; Bargar, J.R.; Druhan, J.; Jew, A.D.; Li, Q.; Brown, G.E. Jr. (2019) Synchrotron x-ray imaging of reactive transport in unconventional shales. Presented at AGU Fall Meeting, symposium H44B: porous media across scales: from interfacial properties to subsurface processes. San Francisco, CA. Dec 12. [Oral]
  11. Li, Q.; Jew, A. D.; Brown G. E. Jr.; Bargar, J. R.; Maher, K. (2019) Reactive transport in shale matrix after fracturing fluid imbibition. Presented at the American Institute of Chemical Engineers (AIChE) Annual Meeting, Orlando, FL. November 10-15. [Oral]
  12. Noël, V.; Fan, W.; Bargar, J.R.; Druhan, J.; Jew, A.D.; Li, Q.; Kovscek, A.R; Brown, G. E. Jr. (2019) Synchrotron x-ray imaging of reactive transport in unconventional shales. Presented at the SSRL annual users meeting, Menlo Park, CA. Sept 25. [Poster]
  13. Jew, A. D.; Harrison, A.; Li, Q.; Cercone, D. P.; Maher, K.; Bargar, J. R.; Brown, G. E. Jr. (2019) Unconventional mineralogy: interactions of hydraulic fracturing fluids with minerals and organic matter in unconventional and tight oil formations. Presented at the Geological Society of America Annual Meeting. Phoenix, AZ. September 23. [Talk]
  14. Li, Q.; Jew, A. D.; Bargar, J. R.; Lopano, C. L.; Hakala, A. J.; Stuckman, M. Y. (2019) Shale-gas-fluid interaction for water and energy. Presented at the ACS National Meeting & Exposition. Orlando, FL. March 31. [Talk]
  15. Jew, A. (2018) Pore Scale Control of Gas and Fluid Transport at Shale Matrix-Fracture Interfaces. Presented research at Mastering the subsurface through technology innovation partnerships and collaboration: carbon storage and oil and natural gas technologies review meeting, Pittsburgh, PA, Aug. 13-16, 2018. [Talk]
  16. Hakala, A.; Morris, J.; Bargar, J. R.; Birkholzer, J. (2018) Fundamental shale interactions-DOE National Laboratory Research. Presented at the DOE Upstream Workshop. Houston, TX. Feb. 14. [Talk]
  17. Jew, A. D.; Cercone, D.; Li, Q.; Dustin, M. K.; Harrison, A. L.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R. (2017) Chemical controls on secondary mineral precipitation of Fe and Ba in hydraulic fracturing systems. Presented at the American Institute of Chemical Engineers (AIChE) Annual Meeting, Minneapolis, MN. Oct. 29-Nov. 3. [Talk]
  18. Li, Q.; Jew, A. D.; Brown, G. E. Jr.; Bargar, J. R. (2017) Chemical reactivity of shale matrixes and the effects of barite scale formation. Presented at the AGU Fall Meeting. New Orleans, LA. Dec. 11-15. [Talk]
  19. Bargar, J.R. (2017) Chemical Control of Fluid Flow and Contaminant Release in Shale Microfractures  Presented at the SLAC National Accelerator Laboratory, August 2017 Carbon Storage and Oil and Natural Gas Technologies Review Meeting, Pittsburgh, PA
  20. Jew, A. D.; Dustin, M. K.; Harrison, A. L.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown G. E. Jr.; Bargar J. R. (2016) The Importance of pH, oxygen, and bitumen on the oxidation and precipitation of Fe(III)-(oxy)hydroxides during hydraulic fracturing of oil/gas shales. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 13. [Talk]
  21. Bargar, J. R.; Kiss, A.; Kohli, A.; Harrison, A. L.; Jew, A. D.; Lim, J.-H.; Liu, Y.; Maher, K.; Zoback, M.; Brown, G. E. Jr. (2016) Synchrotron X-ray imaging to understand porosity development in shales during exposure to hydraulic fracturing fluid. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 12. [Talk]
  22. Harrison, A. L.; Maher, K.; Jew, A. D.; Dustin, M. K.; Kiss, A.; Kohli, A.; Thomas, D. L.; Joe-Wong, C.; Brown G. E. Jr.; Bargar, J. R. (2016) The Impact of Mineralogy on the Geochemical Alteration of Shales During Hydraulic Fracturing Operations. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 13. [Talk]
  23. Bargar, J.R. (2016) Chemical Control of Fluid Flow and Contaminant Release in Shale Microfractures. Presented by John Bargar, National Accelerator Laboratory, 2016 Carbon Storage and Oil and Natural Gas Technologies Review Meeting, Pittsburgh, PA
  24. Harrison, A.; Maher, K.; Jew, A.; Dustin, M.; Kiss, A.; Kohli, A.; Thomas, D.; Joe-Wong, C.; Liu, Y.; Lim, J.-H.; Brown, G. E. Jr.; Bargar, J. (2016) Physical and chemical alteration of shales during hydraulic fracturing. Presented at the Goldschmidt Conference, Yokohama, Japan. June 29. [Talk]
  25. Dustin, M. K.; Jew, A. D.; Harrison, A. L.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown G. E. Jr.; Bargar, J. R. (2015) Kerogen-hydraulic fracture fluid interactions: reactivity and contaminant release. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 14-18. [Talk]
  26. Harrison, A. L.; Jew, A. D.; Dustin, M. K.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R. (2015) A geochemical framework for evaluating shale-hydraulic fracture fluid interactions. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 14-18. [Talk]
  27. Jew, A. D.; Joe-Wong, C.; Harrison, A. L.; Thomas, D. L.; Dustin, M. K.; Brown, G. E. Jr.; Maher, K Bargar, J. R. (2015) Iron release and precipitation in hydraulic fracturing systems. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 14-18. [Talk]
  28. Joe-Wong, C.; Harrison, A. L.; Thomas, D. L.; Dustin, M. K.; Jew, A. D.; Brown, G. E. Jr.; Maher, K.; Bargar, J. R. (2015) Coupled mineral dissolution and precipitation reactions in shale-hydraulic fracturing fluid systems. Presented at the American Geophysical Union Fall Meeting. San Francisco, USA. December 14-18. [Talk]
  29. Harrison, A. L. ; Jew, A. D.; Dustin, M. K.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R. (2015) A geochemical framework for evaluating shale-hydraulic fracture fluid interactions. Presented at the Stanford Center for Secure Carbon Storage Research Seminar. Stanford, USA. October 21. [Talk]
  30. Dustin, M. K.; Jew, A. D.; Harrison, A. L.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown, G. E. Jr.; Bargar, J. R. (2015) Kerogen-hydraulic fracture fluid interactions: reactivity and contaminant release. Presented at the Stanford Synchrotron Radiation Lightsource user’s meeting. Stanford, USA. Oct 7-9. [Talk]
  31. Harrison, A. L.; Jew, A. D.; Dustin, M. K.; Joe-Wong, C.; Thomas, D. L.; Maher, K.; Brown G. E. Jr.; Bargar, J. R. (2015) A geochemical framework for evaluating shale-hydraulic fracture fluid interactions. Presented at the Stanford Synchrotron Radiation Lightsource User’s Meeting, Stanford, USA, Oct 7-9. [Talk]