Marcellus Gas Shale Project

Transcription

1 Marcellus Gas Shale Project Jordan Ciezobka Gas Technology Institute Summary of Results from Completed GTI Marcellus Shale R&D Project Controlled Fracturing of Naturally Fractured Shales May 7, 2013 Canonsburg, Pennsylvania 1 rpsea.org

2 Contacts PI: Jordan Ciezobka Gas Technology Institute RPSEA PM: Kent Perry 2

3 Slide 3 OUTLINE Project description and field test site Microseismic results and validity Pumping diagnostics supporting natural fracture swarms Analysis of microseismic data Event count L/W Aspect ratio Reservoir quality, staying in zone Correlation between microseismic data and production Conclusions 3

4 Slide 4 PROJECT DESCRIPTION Joint industry cooperative field based research and development project Major universities, national laboratory, operator and service company Characterize the Marcellus shale Increase productivity Reduce environmental impact Multiple well pad in Washington County PA 4

5 Slide 5 TEST SITE WELLBORE AND MICROSEISMIC LAYOUT 5

6 Slide 6 MICROSEISMIC RESULTS AND VALIDITY 6

7 Slide 7 TECHNIQUES TO IDENTIFY NATUAL FRACTURES 1. Core Analysis Expensive and limited to near wellbore 2. Image Logs Expensive, sometimes inconclusive and limited to near wellbore 3. Outcrop Studies Do not necessarily translate to subsurface 4. DFIT G-Function analysis to check for PDL, qualitative analysis 5. Subcritical Index Testing Requires samples from core, doesn t give location, rather spacing 6. *Mud Logs In shale reservoirs, high gas shows are should result from intersection of natural fractures, many factors to consider 7. Microseismic Data Event cloud dimensions and event count 8. *Surface treating pressure response during fracturing *Available data on all wells 7

8 PUMPING DIAGNOSTICS Well D Stage 4 Frac Pressure Response Well E Stage 5 Frac Pressure Response Well B Stage 5 Frac Pressure Response Typical Pressure Response 8

9 Slide 9 FRACTURE SWARM? Three fracture stages in adjacent wells with erratic pressure All three stages in same general position along the horizontal All exhibit high microseismic event response 9

10 Slide 10 WELL-D MICROSEISMIC ANALYSIS EVENT COUNT VALIDITY Borehole geophones repositioned 5 times to increase S/N Perforation shots used to recalibrate velocity model 10

11 Slide 11 MICROSEISMIC ANALYSIS L/W ASPECT RATIO Plan view of horizontal wells witch microseismic data for a single frac stage showing the fracture geometry in terms of fracture width and length The fracture width here is the width of the fracture network and not the fracture aperture 11

12 Slide 12 L/W ASPECT RATIO IN THE PRESENCE OF NATURAL FRACTURES 12

13 Slide 13 NATURAL FRACTURE CONCENTRATION FROM MS DATA 13

14 Slide 14 RESERVOIR QUALITY GAMMA RAY Out of Zone One-Column Format 14

15 Slide 15 MUD LOG GAS SHOWS Possible losses and compensation 15

16 Slide 16 COORELATION OF PRODUCTION, GAS SHOWS & MS DATA 1: Mud log gas shows. 2: Fracture Length/Width aspect ratio from microseismic data for each fracture stage. 3: Microseismic event count for each fracture stage. 4: Gas production from each perforation cluster based on production log ran after 4 months on production 16

17 Slide 17 The Big Picture Event Count 17

18 Slide 18 CONCLUSIONS Natural fractures in Marcellus exist in swarm like patterns Microseismic event count Microseismic event cloud L/W aspect ratio Production log results Stimulation efficiency is high in areas of fracture swarms Stimulation efficiency is low in areas void of natural fractures Hydraulic fracture spacing could be improved Check for consistent reservoir quality from gamma ray Evaluate presence of natural fractures from mud log gas shows Validate through real time pumping diagnostics and redesign spacing on the fly 18

19 Slide 19 Acknowledgements / Thank You / Questions Paper # Paper Title Presenter Name 19