Traces In the Dark--Sedimentary Processes and Facies Gradients In the Upper Shale Member of the Upper Devonian-Lower Mississippian Bakken Formation, Williston Basin, North Dakota, U.S.A

The representative sample size in shale oil rocks and nano-scale characterization of transport properties

“…This is consistent with high total organic content found in B1-1 to 4 and B2-1 to B2-2 images as well as low TOC in B3-1 and B4-1. The measured total organic contents for the upper Bakken images were 8-20 vol.% (compare to 3-10 wt.% reported by (Egenhoff and Fishman, 2013)) while it was less than 2 vol.% for the middle Bakken samples. The specific surface area (A s ) was determined by generating three-dimensional pore surfaces using modified marching cube algorithm [Hege et al (1997)] and then dividing the total pore surface area by the total pore volume (Table 1).…”

“…Total organic content, specific surface area, and mean pore aspect ratio for all threedimensional images were calculated through image analysis and are listed in Table 1. The upper shale layer in the Bakken formation is considered as a source rock, while the middle layers store producible oil and are regarded as reservoir rocks [Nojabaei et al (2013); (Egenhoff and Fishman, 2013)]. This is consistent with high total organic content found in B1-1 to 4 and B2-1 to B2-2 images as well as low TOC in B3-1 and B4-1.…”

“…FIB-SEM tomography was utilized here to characterize pore networks in the three upper layers of the Bakken formation. These layers are considered as the major contributors to the hydrocarbon production from this reservoir [Nojabaei et al (2013); (Egenhoff and Fishman, 2013)]. We found that the upper Bakken layer is rich in clay and organic materials, the dominant pore types are pores associated with organic matter, and there is no connected porosity in the preserved core samples analyzed from this layer.…”

Depositional framework of the East Baltic Tremadocian black shale revisited

“…The features of the traces resemble those of ichnofossil Planolites (e.g. Egenhoff & Fishman 2013). More silty laminated beds and some massive beds in the Pakri section showed discontinuous indistinct lamination, halo zones, partly destroyed probable biolamination, diffused surface boundaries and, less commonly, mottled appearances (see also the massive fabric section).…”

Traces In the Dark--Sedimentary Processes and Facies Gradients In the Upper Devonian-Lower Mississippian Upper Shale Member of the Bakken Formation, Williston Basin, North Dakota, U.S.A.--Discussion

“…I would like to comment on a recent paper by Egenhoff and Fishman (2013) that discusses observations made on cores of the Bakken Shale and presents a methodology to examine and describe these cores. In this contribution I would like to discuss some of their observations and conclusions related to perceived bioturbation features.…”