Changes

==Age of minibasin formation==

==Age of minibasin formation==

The age of minibasin formation is determined by looking for relationships between sedimentation and deformation, like faulting or folding. [[:file:sedimentary-basin-analysis_fig4-44.png|Figure 2]] is a schematic diagram of the seismic reflection profile along the west side of the East Breaks 160-161 field ([[:file:Sedimentary-basin-analysis_fig4-42.png|Figure 1]]). That reflection profile is nearly coincident with the boundary between the Galveston and High Island exploration areas ([[:file:Sedimentary-basin-analysis fig4-17.png|Figure 3]]). The diagram depicts salt-cored anticlines and growth faults separating the progradational basin-filling cycles into distinct minibasins. The stratigraphic pattern shows composite depositional sequences, numbered 1 through 4, prograding into and across progressively younger growth-fault and salt-withdrawal basins. The stratigraphic boundaries outline seismic-stratigraphically defined depositional cycles calibrated by bioevents from several wells along the section.<ref name=ch04r10>Armentrout, J. M., and Clement, J., F., 1990, Biostratigraphic calibration of depositional cycles: a case study in High Island–Galveston–East Breaks areas, offshore Texas: Proceedings, Gulf Coast Section SEPM 11th Annual Research Conference, p. 21–51.</ref> Scales are approximate.

The age of minibasin formation is determined by looking for relationships between sedimentation and deformation, like faulting or folding. [[:file:sedimentary-basin-analysis_fig4-44.png|Figure 2]] is a schematic diagram of the seismic reflection profile along the west side of the East Breaks 160-161 field ([[:file:Sedimentary-basin-analysis_fig4-42.png|Figure 1]]). That reflection profile is nearly coincident with the boundary between the Galveston and High Island exploration areas ([[:file:Sedimentary-basin-analysis fig4-17.png|Figure 3]]). The diagram depicts salt-cored anticlines and growth faults separating the progradational basin-filling cycles into distinct minibasins. The stratigraphic pattern shows composite depositional sequences, numbered 1 through 4, prograding into and across progressively younger growth-fault and salt-withdrawal basins. The stratigraphic boundaries outline seismic-stratigraphically defined depositional cycles calibrated by bioevents from several wells along the section.<ref name=ch04r10>Armentrout, J. M., and Clement, J., F., 1990, Biostratigraphic calibration of depositional cycles: a case study in High Island–Galveston–East Breaks areas, offshore Texas: Proceedings, Gulf Coast Section SEPM 11th Annual Research Conference, p. 21–51.</ref> Scales are approximate.

The age of formation of each minibasin can be interpreted from the relative age of expanded sedimentary section downthrown to each major growth fault or salt high. Along the cross section, the expanded section occurs in progressively younger strata. In the northernmost diagrammed minibasin, the expanded section occurs in cycles 1 and 2. In the middle minibasin, the expanded section is in cycles 2 and 3. In the southernmost minibasin (the East Breaks 160-161), the expanded section formed during cycles 3 and 4. Anew minibasin has begun to form in cycle 4 sediments basinward of the steep salt-cored upper slope.

The age of formation of each minibasin can be interpreted from the relative age of expanded sedimentary section downthrown to each major growth fault or salt high. Along the cross section, the expanded section occurs in progressively younger strata. In the northernmost diagrammed minibasin, the expanded section occurs in cycles 1 and 2. In the middle minibasin, the expanded section is in cycles 2 and 3. In the southernmost minibasin (the East Breaks 160-161), the expanded section formed during cycles 3 and 4. Anew minibasin has begun to form in cycle 4 sediments basinward of the steep salt-cored upper slope.