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Line 94: − − [[file:M91FG123.png|thumb|300px|{{figure number|4}}A schematic delta showing a range of sand body types at their average dimensions, together with several oil and gas fields at the same scale. The delta front is divided into three segments that are storm-, fluvial-, and tidal-dominated, respectively. The delta and its divisions are not to scale (from Reynolds<ref name=Reynolds_1999>Reynolds, A. D., 1999, [http://archives.datapages.com/data/bulletns/1999/02feb/0211/0211.htm Dimensions of paralic sandstone bodies]: AAPG Bulletin, v. 83, no. 2, p. 211–229.</ref>).]] − − [[file:M91FG186.JPG|thumb|300px|{{figure number|5}}Fluvial-dominated delta environment, Mississippi Delta. Photograph courtesy of the [http://www.earthasart.gsfc.nasa.gov NASA Web site]. The inset box on the photograph measures 34 times 42 km (21 times 26 mi). The lower diagram is a box diagram showing the sedimentological relationships within the inset box (after Fisk<ref name=Fisk_1961>Fisk, H. N., 1961, [http://archives.datapages.com/data/specpubs/sandsto1/data/a055/a055/0001/0000/0029.htm Bar-finger sands of the Mississippi delta], in J. A. Peterson and J. C. Osmond, eds., Geometry of sandstone bodies: AAPG Symposium, SP22, p. 29–52.</ref>).]] Line 144:
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Sand is deposited within linear distributary channels as side bars. In the modern-day Mahakam Delta, Borneo, side bars alternate on both sides of the distributary channels. These form elliptical sand pods, 5–8 km (3–5 mi) or more long and up to 1 km (0.6 mi) wide.<ref name=Allenandchambers_1998>Allen, G. P., and J. L. C. Chambers, 1998, Sedimentation in the modern and Miocene Mahakam delta: Indonesian Petroleum Association, 236 p.</ref> Channel fills typically show an upward-fining sediment profile and an upward-decreasing permeability profile. From the base upward, a distributary channel comprises the active channel fill, showing decimeter-scale trough cross-bedded sets; a partial abandonment fill with mainly centimeter-scale cross-beds; and sometimes an abandonment channel fill of thinly interbedded fine sand, silt, and shale.
Sand is deposited within linear distributary channels as side bars. In the modern-day Mahakam Delta, Borneo, side bars alternate on both sides of the distributary channels. These form elliptical sand pods, 5–8 km (3–5 mi) or more long and up to 1 km (0.6 mi) wide.<ref name=Allenandchambers_1998>Allen, G. P., and J. L. C. Chambers, 1998, Sedimentation in the modern and Miocene Mahakam delta: Indonesian Petroleum Association, 236 p.</ref> Channel fills typically show an upward-fining sediment profile and an upward-decreasing permeability profile. From the base upward, a distributary channel comprises the active channel fill, showing decimeter-scale trough cross-bedded sets; a partial abandonment fill with mainly centimeter-scale cross-beds; and sometimes an abandonment channel fill of thinly interbedded fine sand, silt, and shale.
==Mouth bars==
==Mouth bars==
| colspan="11" | *''From Reynolds.<ref name=Reynolds_1999 /> N = number.''
| colspan="11" | *''From Reynolds.<ref name=Reynolds_1999 /> N = number.''
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<gallery mode=packed heights=450px widths=400px>
file:M91FG123.png|{{figure number|4}}A schematic delta showing a range of sand body types at their average dimensions, together with several oil and gas fields at the same scale. The delta front is divided into three segments that are storm-, fluvial-, and tidal-dominated, respectively. The delta and its divisions are not to scale (from Reynolds<ref name=Reynolds_1999>Reynolds, A. D., 1999, [http://archives.datapages.com/data/bulletns/1999/02feb/0211/0211.htm Dimensions of paralic sandstone bodies]: AAPG Bulletin, v. 83, no. 2, p. 211–229.</ref>).
file:M91FG186.JPG|{{figure number|5}}Fluvial-dominated delta environment, Mississippi Delta. Photograph courtesy of the [http://www.earthasart.gsfc.nasa.gov NASA Web site]. The inset box on the photograph measures 34 times 42 km (21 times 26 mi). The lower diagram is a box diagram showing the sedimentological relationships within the inset box (after Fisk<ref name=Fisk_1961>Fisk, H. N., 1961, [http://archives.datapages.com/data/specpubs/sandsto1/data/a055/a055/0001/0000/0029.htm Bar-finger sands of the Mississippi delta], in J. A. Peterson and J. C. Osmond, eds., Geometry of sandstone bodies: AAPG Symposium, SP22, p. 29–52.</ref>).
</gallery>
[[file:M91FG187.JPG|thumb|300px|{{figure number|6}}Idealized log and permeability profiles for deltaic sand bodies (from Sneider et al.<ref name=Sneideretal_1978 />). Reprinted with permission from, and © by, the Society of Petroleum Engineers.]]
[[file:M91FG187.JPG|thumb|300px|{{figure number|6}}Idealized log and permeability profiles for deltaic sand bodies (from Sneider et al.<ref name=Sneideretal_1978 />). Reprinted with permission from, and © by, the Society of Petroleum Engineers.]]