Presentation is loading. Please wait.

Presentation is loading. Please wait.

Preliminary Results of Pembina Cardium Core Analysis C.R. Clarkson and N. Solano (PhD Candidate) T O C © TOC, 2011.

Similar presentations


Presentation on theme: "Preliminary Results of Pembina Cardium Core Analysis C.R. Clarkson and N. Solano (PhD Candidate) T O C © TOC, 2011."— Presentation transcript:

1 Preliminary Results of Pembina Cardium Core Analysis C.R. Clarkson and N. Solano (PhD Candidate) T O C © TOC, 2011

2 Outline 1 Objectives Well Locations Sampling and Measurements CT Scans N 2 Adsorption Analysis Comparison to Bakken and 2WS SANS/USANS Future Work T O C

3 Objectives Select low-permeability oil reservoir samples from the Cardium Formation to perform preliminary laboratory experiments Use X-Ray CT Scans to evaluate changes in rock density and porosity and use to evaluate locations for permeability measurements (+ density of measurements) Use low-pressure adsorption and small-angle neutron scattering (SANS and USANS) to establish pore structure characteristics by facies  To date, only “muddier” intervals have been studied Establish controls on pore structure variation Establish relationship between pore structure and permeability 2

4 Sampling/Measurements CORES SAMPLED / ANALYZED: W5, CORE #1, BOXES 3 – W5, CORE #4, BOXES 5 – W5, CORE #1, BOX 11; CORE #2, BOXES 1 – 5; CORE #3, BOXES 1 – 4 (FUTURE) MEASUREMENTS (to date): 1. Coreplugs taken from 8-17 and sub-sampled for SANS/USANS (discs prepared) at NIST (1/2011) and ORNL (3/2011) 2. N2 adsorption analysis performed on 8-17 coreplugs for surface area/PSD (8/2011) and 8-4 full-diameter cores were “scout” (CT) scanned to identify locations for axial scans (7/2011) 4. Axial (CT) scans performed on 8-17 and 8-4 (8/2011) 5. Pulse-decay permeability measurements performed on 8-17 coreplugs 3

5 W W W5 LOCATIONS WITH CORES TO SAMPLE Structure contour map: top of the Cardium SS 4

6 MD (m) CZ Cardium A a b W5 Res 5

7 6 AVAILABLE RCA (Whole core diam.) Kmax, PHI, GRAIN DENSITY SANS/USANS (Horizontal disks 10 mm diameter x 1 mm thick) 3 disks from: m 5 disks from: m INTERVALS TO SAMPLE/ANALYZE CTS: – m SLABBING: – m SAND BLASTING: – m PROBE K: – m XRF: – m CTS 6

8 CT Scans CT Scans: Scout Scans W5 Axial scan location m 7

9 Mean porosity= 9.1% Mean porosity= 7.2% Mean porosity= 8.6% Mean porosity= 7.0% Mean porosity= 7.8% Mean porosity= 7.6% Mean porosity= 7.7% Mean porosity= 4.2% Mean porosity= 6.5% 8

10 CT Scans CT Scans: Scout Scans W5 Axial scan location m 9

11 10 Mean porosity= 10.0% Mean porosity= 13.9% Mean porosity= 15.2% Mean porosity= 21.7% Mean porosity= 18.6% Mean porosity= 14.0% Mean porosity= 12.4% Mean porosity= 10.0% Mean porosity= 13.6% 10

12 CT Scans CT Scans: Scout Scans W5 Axial scan location m Coreplugs 11

13 12 Mean porosity= 9.9% Mean porosity= 9.0% Mean porosity= 9.9% Mean porosity= 9.5% Mean porosity= 10.4% Mean porosity= 8.6% Mean porosity= 8.8% Mean porosity= 8.0% Mean porosity= 9.5% 12

14 CT Scans CT Scans: Scout Scans W5 Axial scan location m Coreplugs 13

15 14 Mean porosity= 7.8% Mean porosity= 7.6% Mean porosity= 7.8% Mean porosity= 9.2% Mean porosity= 8.0% Mean porosity= 7.9% Mean porosity= 9.2% Mean porosity= 7.9% Mean porosity= 6.7% 14

16 N 2 Adsorption/Desorption Isotherms Shape: qualitative assessment of pore structure Adsorption/desorption hysteresis: – Type IV isotherms, mesoporous solids (2 nm < d < 50 nm) – Shape of hysteresis loop can be indicative of pore geometry Interpret isotherm data in terms of surface area (ex. BET Theory) and pore size distributions (ex. BJH Theory) 15

17 N 2 Adsorption/Desorption Isotherms Similar amounts of adsorption for all samples except D2 Substantial mesopore volume Hysteresis loops may be indicative of slit-shaped pores 16

18 N 2 Adsorption/Desorption More adsorption in Bakken, less in 2WS Differences in Hysteresis Loop Shape – pore structure differences? 17

19 N 2 Adsorption/Desorption BJH Analysis (PSD) Capillary condensation of vapours in mesoporous materials Uses Kelvin equation to relate vapour pressure to pore size Can use desorption (convention) or adsorption branch (Figure) – Step AB: removal of capillary condensate – Step BC: removal of condensate from cores, multi-layer thinning of emptied (larger) pores From SPE Desorption analysis using BJH Theory 18

20 N 2 Adsorption/Desorption BJH Analysis (PSD) Primarily unimodal pore size (peak ~ 200 – 350 A, desorption) Artifact at ~ 35 A on desorption curves Small pore size translates into low permeability (later) 19

21 N 2 Adsorption/Desorption Cardium-Bakken, similar pore sizes, but difference in volume 2WS – less mesoporosity 20

22 N 2 Adsorption/Desorption Cardium-Bakken, similar pore sizes, but difference in volume 2WS – less mesoporosity 21

23 N 2 Adsorption/Desorption BJH Analysis (PSD) Effect of degas temperature 22

24 N 2 Adsorption/Desorption BJH Analysis (PSD) Comparison to Montney tight gas reservoir Permeability implications From Clarkson et al. AAPG Bulletin, in press 23

25 N 2 Adsorption/Desorption BET (Surface Area) Extension of Langmuir’s Theory to multilayer adsorption Very common method for surface area analysis From SPE Desorption analysis using BJH Theory 24

26 N 2 Adsorption/Desorption 25

27 N 2 Adsorption/Desorption Relationship to Permeability Can we relate pore structural parameters to permeability (dominant pore size, BET surface area?) Currently gathering permeability/porosity data for Cardium so plot like the one on the right (Montney TG) can be developed From Clarkson et al. AAPG Bulletin, in press 26

28 SANS/USANS In a SANS experiment, a neutron beam is directed at a sample, and the neutrons are elastically scattered due to their interaction with nuclei of atoms in the sample The scattering vector is related to a characteristic length scale (pore size) in the sample SANS experiments, combined with USANS, also enable a wide distribution of pore sizes (~ 0.3 nm to ~ 10 μm) to be investigated From Melnichenko et al. (2009) 27

29 SANS/USANS Analysis 28

30 SANS/USANS Similar scattering patterns for all except: – B1 and B2 exhibit a “hump” at large Q, maybe related to composition Higher scattering intensity generally translates into higher porosity Slope of linear portion of curves (power-law scattering) is close to -3 For surface fractal geometry (equivalent pore space is uncorrelated spherical pores), slope is -3 to -4 SANS USANS 29

31 SANS/USANS Comparison to Montney tight gas reservoir Montney has greater slopes (-3.1 to -3.3) 30

32 SANS/USANS Fit of 1102A1 to PDSP model using PRINSAS 31

33 SANS/USANS Fit of 1101A2 to PDSP model using PRINSAS 32

34 SANS/USANS 33

35 Future Work Gather profile permeability, XRF and additional pulse- decay permeability data Relate pore structural information to permeability Examine compositional and structural controls on porosity and permeability 34


Download ppt "Preliminary Results of Pembina Cardium Core Analysis C.R. Clarkson and N. Solano (PhD Candidate) T O C © TOC, 2011."

Similar presentations


Ads by Google