Integration & Analysis of EO Data For Exploration in the East Africa Rift

Transcription

1 November 2016 For Exploration in the East Africa Rift Martin Insley

2 Acknowledgements Slide 2

3 Presentation Outline Application and of EO data within Tullow Oil Brief overview of Remote Sensing data and criteria for selecting data Applications and Case Studies Summary 75% of Africa s petroleum has been generated during the past 30Ma, and that 50% of it lies in reservoirs of Eocene to Holocene age Burke & Gunnell (2008) Interior Rift Basins of the East African Rift System: Lake Albert, Turkana, Chew Bahir etc. Slide 3

4 Tullow Maps access point to data in the web Data Access and Visibility Easy to use intranet mapping app Access to imagery, bathymetry, scouting data and much more Live RSS feeds from multiple vendors In-house database connections to internally curated datasets House quality print functionality Access point to more bespoke country and function map apps User driven widgets and tools Accessed by over 75% of Tullow staff Slide 4

5 Tullow GIS Desktop Analytics This one is a little bit too sensitive to show.sorry! Slide 5

6 Surface Geological Mapping Slide 6

7 ESA s Copernicus Sentinel & Earth Explorer Missions Long-term (decadal) continuous, consistent data acquisition Designed for Operational Services Repeat Global Coverage Every 6 Days Free and Open Access to data Implication: availability of data will lead to more scrutiny of oil and gas activities from 3 rd Parties Earth Observation business is in a phase of rapid change with companies such a Google potentially establishing constellations Flocks of micro-satellites Operational global monitoring combining optical and radar sensors Primarily acquisitions for scientific community but feed into global gravity, magnetics, land surface temperature and atmospheric measurements etc. High cost, high performance satellite to support operational services versus low cost, low-spec. microsatellites Slide 7

8 SPOT- Pléiades Satellite Constellation Sun-synchronous Polar Orbit at Km Altitude Pléiades 1A Launched Dec 2011 and operational SPOT 6 & 7 1.5m spatial resolution 5 Spectral bands: Pan, RGB and NIR 60 Km swath Daily revisit time Stereo image data SPOT 6 Launched Sept 2012 SPOT 7 Launch scheduled 2014 Pléiades 1A & 1B Pléiades 1B Launched Dec 2012 and operational 0.5m spatial resolution 5 Spectral bands: Pan, RGB and NIR 20 Km swath Daily revisit time Stereo image data Slide 8

9 Airbus GeoStore: Instant Tasking & Near-Real Time Delivery Pre-acquisition times 6-2 hrs Image download can be as good as 45mins for SPOT 6&7 and 1.5 hrs for Pleiades 1&2 depending on ground receiving station Slide 9

10 Swinglet Cam UAV The Way Forward? Slide 10

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14 Spectral Resolution: Landsat 7 ETM+, Landsat 8 OLI-TIRS & WorldView-3 Reflectance spectra for oils spilt from the Prestige and Erika tankers 1730nm SWIR nm SWIR m VNIR Bands 3.7m SWIR Bands Pan WorldView-3 Slide 14

15 Summary: Spatial Resolution and Spectral Slide 15

16 Global DEMS: GTOPO30 SRTM ASTER GDEM GTOPO-30 Completed Arc Seconds = 1 km +/-30m vertical accuracy Composite of various data sources, quality and resolution SRTM Acquired February and 3 Arc Second = 30m and 90m Resolution 20m XY Accuracy +/-10m Vertical Accuracy 60ºN to 56ºS Latitude >80% Land Coverage C and X-Band Radar ASTER GDEM V2 released October arc-second 30m Resolution 30m XY Accuracy 20m Vertical Accuracy 83º N and 83º S latitude 22,600 1º x 1º tiles Slide 16

17 Sentinel 1A Satellite Radar Detection of Natural Oil Seeps Ranking Analysis based on 25 Persistent Seep acquisitions of different Good Confidence Seep date Sentinel 1A SAR Data Poor quality data Moderate Confidence Seep removed from the Low Confidence Seep analysis VV Polarisation data Image enhancement within GIS software Slide 17

18 Tectonic Architecture of East Africa Albertine Rift Turkana Rift Albertine Rift Turkana Rift Albertine Rift Turkana Rift From Tim Craig et al, (2011) Slide 18

19 East Africa Surface Structure From Satellite Imagery Albertine Rift Turkana Rift Slide 19

20 GOCE Free Air Gravity: Albertine Graben Slide 20

21 Albertine Tectonics n Typical Intra-continental Rift Geometry Border fault system switches polarity over accommodation zones Combination of back-to-back, non & overlapping system More diffuse fault style in accommodations zones distributed strain with many low displacement faults 2412m 620m ~1000m Study Area 5109m ~3075m 912m T. Craig et al 2012 Slide 21

22 Lake Albert Tectonics & Basement Fabric NW Basement Foliation Basement Foliation Several tectonic trends observable in basement fabric Opening along:~n50e Likely that rifting exploited existing fabric Current Extension: ~N110E SE Basement Foliation 2.1mm/yr* *Stamps et al 2008 Slide 22

23 Albertine Rift - Western Branch East Africa Rift System Slide 23

24 Modern Day Drainage, Catchment & Erosion Surface a) 14 river - 8 Masystems mimic subsurface b) Ma observations Rift flank uplift & regional tilt rearranged major river systems & lakes c) Ma d) Holocene Cosmogenic Denudation rates: ave 80 mm/kyr Roller et al 2012 Pickford 2011 Slide 24

25 1.5m SPOT 6 Imagery & 20m SPOT DEM Slide 25

26 Comparison of Satellite and LiDAR Elevation Data Profile C-D Subset 1 Profile C-D Subset 2 Sample Spacing 90m SRTM m spacing 30m SRTM m spacing 30m ASTER GDEM m spacing 20m SPOT DEM m spacing 1m LiDAR m spacing Profile C-D 20m SPOT DEM Perspective View SPOT 6 Image Draped Over 1m LiDAR DEM Profile C-D Subset 1 Profile C-D Subset 2 Slide 26

27 MODIS Terra Satellite Land surface Temperature Data 1Km Spatial Resolution; Single Acquisition Date Daytime image Nightime image Night minus daytime image MODIS data product obtained through the online Data Pool at the NASA LP DAAC, USGS EROS Center, Sioux Falls, South Dakota ( Slide 27

28 Regional SRTM: Terrain and Drainage Analysis Drainage analysis - generation of catchments/drainage basins and drainage pattern Application limited to accuracy of DEM Regional basin scale mapping Slide 28

29 Medium Resolution Landsat 4/5 TM, 7 ETM+ Data available from the U.S. Geological Survey 8 Scene Band 742 (RGB) Landsat 7 ETM+ Mosaic (processed by Astrium) 8 Scene Band 453 (RGB) Landsat 7 ETM+ Mosaic (processed by Astrium) Slide 29

30 Landsat 8 OLI-TIRS 16 Day Image Acquisition Data available from the U.S. Geological Survey Slide 30

31 High Resolution SPOT 6 Multispectral Data Orthorectified, mosaiced and enhanced SPOT6 imagery supplied as 123 natural colour Orthorectified, mosaiced and enhanced SPOT6 imagery supplied as 412 false colour Data Processed by: Astrium Services 2013 Includes material Astrium Services 2013), all rights reserved Slide 31

32 High Resolution Pleiades Multispectral Data Delivery 113Gb GeoTIFF 45Gb 8-bit colour balanced orthomosaic 0.5m Spatial Resolution Format: GeoTiff w/ world file Datum: WGS84 Projection: UTM 36 N 51 GeoTIFF Tiles: Data Provided By: i-cubed, LLC Includes material CNES 2013, Distribution Astrium Services / Spot Image S.A., France, all rights reserved Slide 32

33 ALOS PRISM Data: B&W imagery and DEM Panchromatic Remotesensing Instrument for Stereo Mapping (PRISM) optimised for generation of digital elevation maps (DEMs) Band Wavelength Region Pan (µm) Resolution: 2.5m Generation of 10m spatial resolution DEM Includes material JAXA 2013 All Rights reserved distributed by RESTEC Slide 33

34 ALOS PALSAR L-Band Microwave Satellite Imagery Includes material METI-JAXA 2012 All Rights reserved distributed by RESTEC Slide 34

35 East Africa Surface Structure Chew Bahir example of a hard-linked rift basin Slide 35

36 East Africa Surface Structure: Chew Bahir Hard-Linkage Detail Hard-linkage controlled by pre-existing fabric elements in the Basement forming an inherent anisotropic weakness: NNW-SSE metamorphic fabric ENE-WSW to E-W trending dyke swarm and brittle extensional faults Sediment entry points Basaltic lava directly overlying peneplained Basement Slide 36

37 1.5m Spatial Resolution SPOT Satellite Imagery Slide 37

38 Landsat 8 TIR Surface Temperature Slide 38

39 Landsat 8 OLI Sultan Band Ratio image Slide 39

40 PALSAR L-Band Radar Backscatter image and Classified by Surface Roughness Slide 40

41 Topography & Satellite Radar Imagery Slide 41

42 Surface Geology Mapping to 1:10,000 Scale Slide 42

43 Surface Geology: Rock Outcrop versus Pliocene-Holocene Deposits and Lithology Slide 43

44 Mapping Subtle Surface Expression of Faults Aim To identify and map possible surface expression of underlying faults related to break-in-slope; linear contrasts in spectral properties; abrupt changes in drainage pattern including deflected drainage Data Sources Landsat 8 OLI January 31 st 2016 Natural Colour composite Spectrally enhanced to highlight subtle changes in mineralogy of surface material 0.5m spatial resolution Pleiades satellite imagery for mapping at 1:5000 scale Digital elevation data including 30m SRTM, 1m Pleiades DEM and elevation surface derived from 3D seismic source points; sun-shaded and curvature analysis Slide 44

45 Mapping Subtle Surface Expression of Faults (2) Mapped surface traces of underlying faults (white barbed lines); red lines are the major extensional faults mapped on seismic and projected to surface 1m spatial resolution Pleiades DEM and 0.5m satellite imagery with and without interpretation Slide 45

46 Summary Hydrocarbon exploration cycle is focused on the subsurface so Earth Observation data is only part of the story Emphasis higher spatial resolution > spectral resolution Access to freely available GIS-ready EO datasets; mainly applies to medium resolution imagery with limited application? Near-real time delivery of newly acquired premium data Integration of EO data into traditional geophysical software packages ArcMap Increasing image processing capability; increasing use of WMS resources Benefits: Regional exploration - more accurate delineation of basin geometry and structures with potential to map source, reservoir and seal units Global gravity and magnetic data to determine subsurface geometry of basins Free-sky policy Slide 46

47 Follow Tullow on: Tullow Oil plc 9 Chiswick Park 566 Chiswick High Road London, W4 5XT United Kingdom Tel: +44 (0) Fax: +44 (0)