PROSPECT EVALUATION OF UNCONVENTIONAL PLAYS IN RUSSIA EPUG 2014

Transcription

1 PROSPECT EVALUATION OF UNCONVENTIONAL PLAYS IN RUSSIA EPUG 2014

2 Main definitions AGENDA Shale/shale play definition - Organic matter content - Thermal maturity Potential for unconventionals development in Russia - Identification of geological controls and choosing relevant proxies - Preparation of data - Creating risk and volume maps - Play segmentation - Creating Chance of Success (COS) map - License area segmentation - Wells placement Prospect evaluation of unconventional plays in Russia London, UK November 7th,

3 WHAT IS A SHALE AND A SHALE PLAY? Shale is a fine-grained sedimentary rock that forms from the compaction of silt and claysize mineral particles that are commonly called mud dark colour due to organic matter A shale play is a defined geographic area containing an organic-rich fine-grained sedimentary rock with the following characteristics: Clay to silt sized particles (< mm) High % of silica (and sometimes carbonates) (> 40%) Thermally mature Hydrocarbon-filled porosity Low permeability (< 0.1 millidarcy) Large areal distribution Fracture stimulation required for economic production Source: Presentation by J. Caputo at AAPL s 57 th Annual Meeting, June 8-11, 2011, Boston Prospect evaluation of unconventional plays in Russia London, UK November 7th,

4 ORGANIC MATTER CONTENT Shale plays are found in deep water basinal settings In most shale plays organic matter is derived from single celled marine organisms Organic matter (OM) deposition in deep marine waters As organisms die they fall to the sea floor Organic matter mixes with terrestrial input (mainly clays) and carbonate debris (from shallow marine shelf), along with silica (quartz) from the organisms Total Organic Carbon content (TOC) measured in weight percent of the rock is a measure of the rock richness in OM Source: Kerogen is pre-mature organic matter Prospect evaluation of unconventional plays in Russia London, UK November 7th,

5 THERMAL MATURITY As OM is buried it is subjected to increasing pressure and heat With sufficient burial OM physically transforms to kerogen Kerogen transforms to oil and then gas with additional heat and pressure Thermal maturity measures the degree to which a formation has been exposed to high heat needed to break down organic matter into hydrocarbons Thermal maturity indicators: - The reflectance of certain types of minerals (Ro%) - Hydrogen index (HI) Source: EIA/ARI World Shale Gas and Shale Oil Resource Assessment, 2013 Prospect evaluation of unconventional plays in Russia London, UK November 7th,

6 POTENTIAL FOR UNCONVENTIONALS DEVELOPMENT IN RUSSIA* Area more than 2M km² (greater than any current US play under development) Proven organically rich shale Mature organic matter Well developed infrastructure Overpressure up to 70% Estimated recoverable volumes of oil from 30 to 74B bbl *West Siberia basin focus Source: Ulmishek, 2003 Prospect evaluation of unconventional plays in Russia London, UK November 7th,

7 MAP-BASED PLAY ASSESSMENT Proxy maps TOC zones HI map (maturity indicator) Top depth map Structural position Thickness map Source: Total Identify play elements and choose proxies Prepare data in ArcGIS and geomodeling software (e.g. Petrel) Create risk and volume maps Make segmentation of the play* Create Common Risk Segment (CRS) and Common Volume Segment (CVS) maps * in our case evaluated licenses were considered as segments Prospect evaluation of unconventional plays in Russia London, UK November 7th,

8 USING GIS FACILITATES THE ASSESSMENT PROCESS Geomodeling software Reports Contractors Databases Other sources Maps Database GIS serves as a platform for integration of data from various sources These data can be easily visualized as different maps GIS allows quick access to lots of data available within the company Prospect evaluation of unconventional plays in Russia London, UK November 7th,

9 FROM THE RESOURCE DENSITY MAP TO AVERAGE VALUE PER BLOCK STOIIP Stock Tank Oil Initially In-Place STOIIP A h NTG S B o o Spatial Analyst extension allows calculating average values per segment Prospect evaluation of unconventional plays in Russia London, UK November 7th,

10 SURFACE ASSESSMENT Flood plain GIS allows making rather precise estimation of surface accessibility Various types of data may be used if necessary (satellite images, topographic maps) Easy way to calculate effective surface for a large number of licenses Prospect evaluation of unconventional plays in Russia London, UK November 7th,

11 Stacking CHANCE OF SUCCESS (COS) MAP POS ad COS maps may be obtained using standard GIS functionality (rather complicated for raster data) In our case a dedicated ArcGIS tool simplifying the process was used Prospect evaluation of unconventional plays in Russia London, UK November 7th,

12 RISKED RESOURCE DENSITY Chance of Success map Resource density map Prospect evaluation of unconventional plays in Russia London, UK November 7th,

13 CONSTANT IMPROVEMENT OF THE MODEL Input data Adjust risk model COS map Risked resource density map Prospectivity map Pilot well Resource density map Input data Continue drilling Using GIS helps quickly integrate new data The risk model can be validated or modified if necessary as new data becomes available Prospect evaluation of unconventional plays in Russia London, UK November 7th,

14 LICENSE G SEGMENTATION Maturity zone 1 Maturity zone 2 Maturity zone 3 Maturity zone 4 Parameters used for segmentation: Maturity zones Carbonates presence Structural closures Carbonate presence zones Maturity zone 5 Prospect evaluation of unconventional plays in Russia London, UK November 7th,

15 WELLS PLACEMENT FOR LICENSE G No wells to be drilled within the flood area 640 ac spacing for wells drilled within structural closures No wells to be drilled within fractured areas 320 ac spacing for the rest of the license Special ArcGIS extension was used to: Create constraints dataset Place the wells within the license Assign drilling dates based on the prospectivity map Prospect evaluation of unconventional plays in Russia London, UK November 7th,

16 CONCLUSIONS When assessing unconventional plays GIS may serve as a platform to integrate various data Special ArcGIS extensions allow geologists who do not have strong GIS skills easy access to some advanced GIS functionality GIS facilitates leases as it allows calculating average values of continuous data per license area, and these values can further be used for ranking or this may be done using dedicated tools of ArcGIS extensions Future s may also take into consideration proximity of leases to roads, pipelines, etc. Using GIS we can quickly adjust used risk model as pilot projects results become available Development of unconventional plays requires extensive drilling, GIS in turn helps to estimate accessible surface. Using dedicated extensions it is possible to make wells placement and plan drilling activities Prospect evaluation of unconventional plays in Russia London, UK November 7th,

17 THANK YOU FOR YOUR ATTENTION Prospect evaluation of unconventional plays in Russia London, UK November 7th,