Changes

The Codell Sandstone in Wattenberg is an impermeable, bioturbated, fine-grained marine shelf sandstone<ref name=WeimSonnen1983 />. Occasional thin hummocky cross-stratified beds (1–2 ft thick) are present in cores and the outcrop sections of the Codell ([[:file:M125-WattenbergField-Figure20.jpg|Figures 20]], [[:file:M125-WattenbergField-Figure21.jpg|21]]). The Codell Sandstone in Wattenberg is poorly to moderately sorted, very fine- to fine-grained sublitharenites and subarkose. Slight to moderate compaction and ductile grain deformation is common. Partial dissolution of chert and mica has created minor amounts of secondary porosity. Cements include mixed layer illite/smectite, illite, chlorite, quartz overgrowths, and calcite. Detrital clay further limits reservoir quality. The Codell in Wattenberg is a classic low-resistivity, low-contrast pay (LRLC; [[:file:M125-WattenbergField-Figure7.jpg|Figures 7]], [[:file:M125-WattenbergField-Figure20.jpg|20]]).

The Codell Sandstone in Wattenberg is an impermeable, bioturbated, fine-grained marine shelf sandstone<ref name=WeimSonnen1983 />. Occasional thin hummocky cross-stratified beds (1–2 ft thick) are present in cores and the outcrop sections of the Codell ([[:file:M125-WattenbergField-Figure20.jpg|Figures 20]], [[:file:M125-WattenbergField-Figure21.jpg|21]]). The Codell Sandstone in Wattenberg is poorly to moderately sorted, very fine- to fine-grained sublitharenites and subarkose. Slight to moderate compaction and ductile grain deformation is common. Partial dissolution of chert and mica has created minor amounts of secondary porosity. Cements include mixed layer illite/smectite, illite, chlorite, quartz overgrowths, and calcite. Detrital clay further limits reservoir quality. The Codell in Wattenberg is a classic low-resistivity, low-contrast pay (LRLC; [[:file:M125-WattenbergField-Figure7.jpg|Figures 7]], [[:file:M125-WattenbergField-Figure20.jpg|20]]).

[[file:M125-WattenbergField-Figure20.jpg|center|framed|300 px|{{Figure number|20}}(A) Type log Codell Sandstone, Wattenberg Field. Gamma ray, spontaneous potential, resistivity, neutron, and density curves shown. Codell is a low resistivity, low contrast pay. (B) X-ray diffraction data for the Dome Frank core<ref name=USGS>[http://geology.cr.usgs.gov/crc/ USGS Core Research Center], 2015, accessed February 4, 2021.</ref>.

[[file:M125-WattenbergField-Figure20.jpg|center|framed|300 px|{{Figure number|20}}(A) Type log Codell Sandstone, Wattenberg Field. Gamma ray, spontaneous potential, resistivity, neutron, and density curves shown. Codell is a low resistivity, low contrast pay. (B) X-ray diffraction data for the Dome Frank core<ref name=USGS>[http://geology.cr.usgs.gov/crc/ USGS Core Research Center], 2015, accessed February 4, 2021.</ref>.]]

[[file:M125-WattenbergField-Figure21.jpg|center|framed|300 px|{{Figure number|21}}Core photographs of Dome Frank Codell core. Two distinct facies are present in core: (1) bioturbated sandstone and (2) low-angle cross stratified (hummocky beds). Unconformities are present at the top and base of Codell. From USGS Core Research Center<ref name=USGS />.]]

[[file:M125-WattenbergField-Figure21.jpg|center|framed|300 px|{{Figure number|21}}Core photographs of Dome Frank Codell core. Two distinct facies are present in core: (1) bioturbated sandstone and (2) low-angle cross stratified (hummocky beds). Unconformities are present at the top and base of Codell. From USGS Core Research Center<ref name=USGS />.]]