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Of the 240 wells used in the study area, 147 penetrated the ''Glob alt'' interval and provided information on the distribution of the net sand deposited within that interval. Using the net-sand values from the wells, we integrate the data with seismic facies maps within the ''Glob alt'' lowstand [[isochron]] and contour a net-sand isopach map ([[:file:sedimentary-basin-analysis_fig4-38.png|Figure 5]]). Contours are for areas with at least [[length::200 ft]] (60 m) of net sand. The sandstones occur mostly seaward of the age-equivalent physiographic shelf/slope break identified on the seismic-reflection profiles. Because most of the wells penetrated the ''Glob alt'' sequence basinward of the ''Glob alt'' shelf edge, the sandstones penetrated were most likely transported by gravityflow processes and deposited in environments on the slope and within intraslope basins.
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Of the 240 wells used in the study area, 147 penetrated the ''Glob alt'' interval and provided information on the distribution of the net sand deposited within that interval. Using the net-sand values from the wells, we integrate the data with [http://wiki.seg.org/wiki/Dictionary:Seismic_facies seismic facies] maps within the ''Glob alt'' [[Sea_level_cycle_phase_and_systems_tracts#Lowstand_systems_tracts|lowstand]] [[isochron]] and contour a net-sand [[Subsurface_maps#Isopach|isopach map]] ([[:file:sedimentary-basin-analysis_fig4-38.png|Figure 5]]). [[Contour]]s are for areas with at least [[length::200 ft]] (60 m) of net sand. The sandstones occur mostly seaward of the age-equivalent physiographic [http://education.nationalgeographic.com/education/encyclopedia/continental-shelf]/?ar_a=1 shelf/[http://www.thefreedictionary.com/continental+slope slope] break identified on the seismic reflection profiles. Because most of the wells penetrated the ''Glob alt'' sequence basinward of the ''Glob alt'' shelf edge, the sandstones penetrated were most likely transported by gravity flow processes and deposited in environments on the slope and within intraslope basins.
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The resulting map shows the net-sand distribution of shelf areas contoured parallel to the shelf edge and slope areas contoured parallel to the depositional dip of the slope valleys down which the sand was transported. The distribution of sand within the depositional dip-oriented isopachs is consistent with the regional pattern of downslope-oriented salt withdrawal valleys bounded by salt-cored anticlines ([[:file:sedimentary-basin-analysis_fig4-6.png|Figures 8]] and [[:file:sedimentary-basin-analysis_fig4-41.png|9]]). Note the lowstand position of the middle-to-outer neritic [[Fossil assemblage|biofacies]] boundary, below which few waves reach the sea floor. This results in downslope sand distribution being controlled by bottom currents alone.
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The resulting map shows the net-sand distribution of shelf areas contoured parallel to the shelf edge and slope areas contoured parallel to the depositional [[dip]] of the slope valleys down which the sand was transported. The distribution of sand within the depositional dip-oriented isopachs is consistent with the regional pattern of downslope-oriented [[Halite|salt]] withdrawal valleys bounded by salt-cored anticlines ([[:file:sedimentary-basin-analysis_fig4-6.png|Figures 8]] and [[:file:sedimentary-basin-analysis_fig4-41.png|9]]). Note the lowstand position of the middle-to-outer [http://www.onr.navy.mil/focus/ocean/regions/bluewater1.htm neritic] [[Fossil assemblage|biofacies]] boundary, below which few waves reach the sea floor. This results in downslope sand distribution being controlled by bottom currents alone.
    
==Depositional facies map==
 
==Depositional facies map==
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