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Line 63: − 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 ([[:figure 4-38). 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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==Net sand map==
==Net sand map==
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 (Figures 4-6 and 4-41). Note the lowstand position of the middle-to-outer neritic biofacies boundary, below which few waves reach the sea floor. This results in downslope sand distribution being controlled by bottom currents alone.
[[file:sedimentary-basin-analysis_fig4-6.png|thumb|{{figure number|8}}.]]
[[file:sedimentary-basin-analysis_fig4-41.png|thumb|{{figure number|9}}.]]
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.
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 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==