ChromaStratigraphy : the New Stratigraphic Analysis Tool

Transcription

1 ChromaStratigraphy : the New Stratigraphic Analysis Tool William E. Ellington, Jr., Jacob C. Moore, Nancy L. Engelhardt-Moore, Doug Kneis Ellington & Associates, Inc.

2 Introduction Orders of Geologic Truth 4 6 5

3 Introduction Lower Eagle Ford Buda Fm. Source: Peschier & Lock (SIPES 00)

4 Introduction Factors that Influence Color Mineralogy Lithology Grain size Cementation Thermal history P-T path Hydrocarbon Generation Geochemistry Inorganic compounds (sulfides, etc.) Organic compounds (TOC) Redox conditions at deposition Post-depositional chemical alteration

5 Introduction to ChromaStratigraphy

6 Introduction to ChromaLog Sample Prep in Slurry Form Selected cuttings representative of entire sample Combine cleaned cuttings and water Reveals more color variation than dried cuttings or slides

7 Introduction to ChromaLog Changing Color Color Purity Darker Lighter Line Scale: 00 Well-log display of quantified chromatic data

8 ChromaLog Analysis Well A Slurries Significant color variation in slurry samples Top Easy-to-see pattern Color variation can be measured Bottom Depth increases with Row then Column

9 ChromaLog Analysis Color Group Well A ChromaLog Results of analysis Color ratio curves Scale : :5000 Well A CHM ChromaLog Value 00 0 R/RGB G/RGB B/RGB R/G R/B G/B Measured Chroma-Core Color 4 5 Scale: 00 /Subdivision

10 ChromaLog Analysis Color Group Well B ChromaLog Results similar to Well A Scale : :5000 Well B CHM ChromaLog 4 Value 00 0 R/RGB G/RGB B/RGB R/G R/B G/B Measured Chroma-Core Color 4 5 Scale: 00 /Subdivision

11 Introduction to ChromaLog Color Group Color Group Scale: 00 /Subdivision ChromaLog Comparison Integrated Display with GR and ChromaLog results Scale : :5000 CHM Well A ChromaLog R/RGB G/RGB R/G R/B GR Value B/RGB G/B 0 API Measured Chroma-Core Color Scale : :5000 CHM 4 Well B ChromaLog R/RGB G/RGB R/G R/B Value B/RGB G/B Measured Chroma-Core Color

12 ChromaStratigraphy Examples High-res ChromaStratigraphy Correlation based on 5-foot samples Chroma-Core Chroma-Core Chroma-Core Taylor/Austin Eagle Ford Buda Scale: 50 /Subdivision The chromatic changes can be integrated with geochemical, paleo, wire-line, or other geologic data.

13 ChromaStratigraphy Examples Color Group Color Group Color Group Color Group Regional Correlations ChromaStratigraphy correlation from local to basin-scale Color Measured Group Chroma-Core Color Value 00-0 Color Value Measured Chroma-Core Color Measured Chroma-Core Color Value 00 0 Color Value Measured Chroma-Core Color Measured Chroma-Core Color Value 00 0 Taylor/ Austin Eagle Ford Scale: 00 /Subdivision Buda Over 50 miles The section shows distinct correlatable changes in the Austin-to-Buda stratigraphic interval.

14 Application of ChromaStratigraphy Analysis in a Lateral Well

15 ChromaStratigraphy in a Lateral General Eagle Ford Stratigraphy Austin Chalk Boquillas (not observed everywhere) Upper Eagle Ford Lower Eagle Ford Turonian Cenomanian Buda Limestone not to scale

16 ChromaStratigraphy in a Lateral Lateral Applications Fault or Dep. Hiatus Nannofossil-derived lithologic formations (lower panels) Identified fault/depositional hiatus between Lower and Upper Eagle Ford in lateral

17 ChromaStratigraphy in a Lateral Schematic Paleo Results in lateral format Age Late Cenomanian Latest Turonian Formation Lower Eagle Ford Upper Eagle Ford Boquillas Austin Chalk Fault or Dep. Hiatus Drilling Upsection Direction of Drilling

18 ChromaStratigraphy in a Lateral Lateral Applications Chroma-Core for lateral well

19 ChromaStratigraphy in a Lateral Lateral Applications Samples from the Lower Eagle Ford are significantly darker than others Gradual lightening as move upsection from Upper Eagle Ford to the basal Austin Chalk

20 ChromaStratigraphy in a Lateral Lateral Applications

21 ChromaStratigraphy in a Lateral Red/Blue Lower Eagle Ford Upper Eagle Ford Boquillas.5.4. Austin Chalk Color Value (0 = Black, 00 = White)

22 ChromaStratigraphy in a Lateral Red/Blue Lower Eagle Ford Upper Eagle Ford Lateral Pilot.6 Boquillas.5.4. Austin Chalk Color Value (0 = Black, 00 = White)

23 ChromaStratigraphy in a Lateral Lateral Applications Extrapolate from established color groups to classify samples without paleo control ChromaStratigraphy is a zonation and identification tool!

24 Chromatic Data as a Proxy for TOC

25 ChromaTOC TOC (wt%) 6 US Onshore Play Color Value (0 = Black, 00 = White) Relationships between color and TOC are formation and play specific

26 ChromaTOC TOC (wt%) 6 R² = 0.6 US Onshore Play ln(value) Linearized relationship

27 ChromaTOC Scale: 50 /Subdivision Chroma-Core ChromaTOC Increase in TOC through Eagle Ford also observed in grayscale Value Determine formation specific relationship and calculate ChromaTOC

28 TOC (wt%) ChromaTOC Scale: 50 /Subdivision Chroma-Core ChromaTOC 6 R² = ln(value)

29 TOC (wt%) ChromaTOC Scale: 50 /Subdivision Chroma-Core ChromaTOC 6 R² = ln(value)

30 Integrated Results

31 Scale: 50 /Subdivision Integrated Color Results Santonian late Coniacian late Turonian Cenomanian CC 9 - CC 8 CC - CC CC 4 - CC 7 CC 0 Lower Taylor Formation Austin Chalk Eagle Ford Geochemical Package Nanno Abund Nanno Div Stage from Nannos early Campanian Nanno Events NPHI Depth Color Group Measured Quartz Clays Calcite Chroma-Core Color 0 wt% 5 0 wt% 5 0 wt% 00 Value TOC SiO AlO CaO wt% 5 0 wt% 50 0 wt% 5 0 wt% early Turonian CC CC 9 Grayson Marl Buda Limestone 900 Integrated Paleo, TOC, XRF, XRD, and ChromaLog for time-sensitive decision making

32 ChromaStratigraphy Summary Critical Observations ChromaLog analysis is fast and easy, < 0 minutes Minimum sample required for analysis (< gram) Used on cuttings, core, & outcrop samples Any type of rock sample can be analyzed for color Lithologic interpretation tool Quantify what your eyes see into a robust well log Color Makes the Difference!

33 ChromaStratigraphy Summary Critical Observations ChromaStratigraphy is a powerful stratigraphic technique Identify and categorize formations from color alone! ChromaTOC as a proxy for organic carbon provides a fast and inexpensive screening tool Can be a substitute if no well log data is available Can be done on stored well samples Useful in screening intervals for various analyses Color Makes the Difference!

34 ChromaLog & ChromaStratigraphy Future Directions Patent Pending, technology trademarked! Developing advanced protocols & techniques Wellsite service (now operational!) Rapid ChromaLog generation onsite Aid in picking tops Stratigraphic positioning Color-steering E&A and Empirica have jointly constructed a portable Advanced Service Mobile Rock Lab that has just completed the first well-site test with timely and excellent results!