Organic matter may play an important role in the storage and transport of hydrocarbons in shale reservoirs. In some shales a significant amount of porosity is located in the organic matter and how well that organic matter is connected is crucial for the creation of possible flow pathways. The distribution of organic matter also affects the elastic properties and anisotropy of the shales which is important from a completions and seismic mapping standpoint. Because of the heterogeneity of shales and micron to sub-micron size of the organic matter, mapping changes in organic distribution with sufficient resolution to capture all the organic matter has proven difficult. With the advent of large area ion beam milling and automated high-resolution SEM imaging-stitching, the distribution of organic matter can now be mapped on centimeter-sized areas with nanometer resolution. Using these methods we investigate the distribution of organic matter within a sample of the Wolfcamp shale. Results from the SEM mapping suggest that over 50% of the organic matter in the sample consists of sub-100 nm regions. In addition, most of the organic matter is elongated in shape and locally disorganized with organization increasing somewhat with increasing organic matter size.

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