TABLE 1. Neutron radiograph data collection parameters for illustrated specimen (PL1227).

Scan parameter Value
Total sample dimensions (mm) 62×58×14
Scintillator composition ZnS/6LiF
Scintillator dimensions (mm) 100x100x0.05
Rotation angle (°) 0.25
Total rotation (°) 180
Projections 720
No. of frames/projection 3
Frame exposure (secs) 60
No. of dark and beam profile images 6 each
Radiograph pixel width (mm) 0.0161

 

TABLE 2. Resin volume estimates and segmentation thresholds, all values are from visualisations performed with Avizo 9.0.1, volumes based on voxel diameter = 16.1 μm, “max.” and “min.” refer to the software maximum and minimum absolute spectrum values (0 and 65535, respectively), total = coalified plant remains + fossil resin, relative resin volume (%) = (fossil resin / total) × 100.

  Neutron attenuation segmentation thresholds  Volume
(no. of voxels)
 Volume
(μm3)
 
Medium Lower Upper
Air Min. 30700 - -
Matrix 30700 38500 1.60×10 6.67×1012
Bract-scale complex 1        
Coalified plant remains 38500 52250 1.59×10 6.65×10
Fossil resin 52250 Max. 2.61×10 1.09×10
Total 38500 Max. 1.62×10 6.76×10
Relative resin volume (%)       1.61
Bract-scale complex 2        
Coalified plant remains 38500 52250 7.05×10 2.94×10
Fossil resin 52250 Max. 6.65×10 2.78×10
Total 38500 Max. 7.12×10 2.97×10
Relative resin volume (%)       0.94
Bract-scale complex 3        
Coalified plant remains 38500 52250 1.14×10 4.74×10
Fossil resin 52250 Max. 9.98×10 4.16×10
Total 38500 Max. 1.15×10 4.78×10
Relative resin volume (%)       0.87
Bract-scale complex 4        
Coalified cone scale 38500 52250 8.49×10 3.54×10
Fossil resin 52250 Max. 1.13×10 4.73×10
Total 38500 Max. 8.60×10 3.59×10
Relative resin volume (%)       1.32