PICEANCE BASIN fractured reservoir detection methodologies

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Existing extensive stratigraphic studies across the basin have not fully resolved the strong tectonic elements that control fracturing in the basin.  This is unfortunate because tectonic fractures are the key to reservoir producibility.  

This study integrates seismic calibrated high-resolution aeromagnetics with less detailed NURE regional magnetics.  In addition, SAR (synthetic aperture radar), and LANDSAT 8 Thematic Mapper TM were integrated into the study to examine surficial expressions of deeper tectonic elements.   

 Ongoing work incorporating very high spatial resolution LIDAR data will further document some of these features.

We have published several papers that summarize our approach and results of our methodology.

HIGH RESOLUTION SURVEY:

N-S flight lines acquired at ¼ mile spacing with E-W tie lines flown at 1 mile.  

Flight altitude was 500 feet AGL flown in drape mode.  

Data were collected with a cesium vapor magnetometer with a resolution of .001 nT and a cycle rate of 0.1 seconds yielding a sample interval of approximately 10 meters along the flight lines

REGIONAL SURVEY: (NURE)

E-W flight lines at 3 mile spacing, with N-S tie lines at 12 mile line spacing.  

Flight altitude was 400 feet AGL flown in drape mode.  

Proton precession magnetometer with a resolution of 1nT.  

Sample rate was one second.  Sampling rate was one hertz yielding a sample interval of approximately 100 meters along flight lines.

1:100K MAPS (TIFF FILES) and  Geosoft GRIDS (X-Y-Z) in addition to raw flight data are included:    

Flight line locations.

Total field intensity.

Total Field intensity (RTP-reduced to pole).  

Horizontal Derivative of RTP.

Three pseudo-depth slices: Shallow, intermediate and basement level depth slices.

1:500K MAPS (TIFF FILES) and Geosoft GRIDS (X-Y-Z) in addition to raw flight data are included:    

Flight lines and basemap. 

Total field magnetic intensity.    

Magnetic residual (IGRF removed).

Magnetic residual RTP (reduced to pole).   

Total Field (TRP-reduced to pole).  

Horizontal Gradient of RTP.

First Vertical Derivative of RTP.  

RTP Color Hillshade. 

Two pseudo- depth slices: Intermediate and basement level slices.

Horizontal gradient of basement level slice.

1:250K map products. 

Data are X-band synthetic aperture radar (horizontally transmitted, horizontally received). 

The source data for the SAR images were acquired between 1980 and 1994.  

Note that because of different radar- look-directions in the images, we have not made a mosaic of the various scenes.  This minimizes interpreter confusion and makes for a cleaner image.

A basin encompassing SAR mosaic was generated from Sentinel 1B imagery.  This C band orbital instrument acquired data in high spatial 20 meter resolution in September 2017.  Look direction was towards the ENE.  both scaled hardcopy and digital images are available for this mosaic.

LANDSAT 8 TM Imagery Mosaic encompassing the entire basin    

1:100,000 scale, geocoded, false color infrared hybrid composite image generated from three 30 meter spatial resolution spectral bands digitally merged with the 15 meter spatial resolution panchromatic band.  Both the scaled TIFF format images are included.  

Included with these image maps are the four individual Landsat 8 digital scenes used for the mosaicked composite image.

Digital elevation models (DEM) are available for the basin in a variety of spatial resolutions.  Included in our data package are the contiguous 10 meter NED DEM data.  A very high spatial 1 meter resolution GSC is being constructed from LIDAR at the present time.  

LIDAR coverage for the Piceance Basin is presented in the graphic below.  

We are in the process of acquiring and analyzing this data in specific regions to evaluate its utility for mapping surficial structures and their relationship to subsurface fracture orientations and deeper structural features.