Changes

[[file:M125-WattenbergField-Figure18.jpg|center|framed|300 px|{{Figure number|18}}Isopach map of the Codell Sandstone; contour interval 10 ft. Codell ranges in thickness from 5 to 30 ft across the mapped area. Thickest area is to the west. Codell is a low-resistivity, low-contrast pay as shown on [[:file:M125-WattenbergField-Figure20.jpg|Figure 20]]. GWA = Greater Wattenberg Area. Blue dashed lines show area where Codell is productive. Red dashed lines show Codell overpressured area (>0.5 psi/ft). Contour interval 5 ft.]]

[[file:M125-WattenbergField-Figure18.jpg|center|framed|300 px|{{Figure number|18}}Isopach map of the Codell Sandstone; contour interval 10 ft. Codell ranges in thickness from 5 to 30 ft across the mapped area. Thickest area is to the west. Codell is a low-resistivity, low-contrast pay as shown on [[:file:M125-WattenbergField-Figure20.jpg|Figure 20]]. GWA = Greater Wattenberg Area. Blue dashed lines show area where Codell is productive. Red dashed lines show Codell overpressured area (>0.5 psi/ft). Contour interval 5 ft.]]

[[file:M125-WattenbergField-Figure19.jpg|center|framed|300 px|{{Figure number|19}}Isopach map of the Codell Sandstone, porosity greater than 6% using 2.68 matrix density; contour interval 5 ft. Porous Codell ranges in thickness from 5 to 25 ft across the mapped area. Thickest area is to the west. Codell pressure greater than 0.5 psi within orange dashed area. Synclinal axis at Codell level shown by dashed gray line. Outline of where Codell produces shown by dashed blue line. GWA = Greater Wattenberg Area.]]

[[file:M125-WattenbergField-Figure19.jpg|center|framed|300 px|{{Figure number|19}}Isopach map of the Codell Sandstone, porosity greater than 6% using 2.68 matrix density; contour interval 5 ft. Porous Codell ranges in thickness from 5 to 25 ft across the mapped area. Thickest area is to the west. Codell pressure greater than 0.5 psi within orange dashed area. Synclinal axis at Codell level shown by dashed gray line. Outline of where Codell produces shown by dashed blue line. GWA = Greater Wattenberg Area.]]

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]]).