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Abstract:
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This study uses a new integrated outcrop data and airborne lidar from Slaughter Canyon , New Mexico , to quantitatively characterize the cycle -scale facies architecture within the G23 -G26 high frequency sequences of the Yates Formation . High frequency cycle -scale mapping of these sequences shows sedimentological evidence for accommodation reduction associated with the Permain composite sequence (CS ) 13 highstand (G23 -G25 ) . Development of the G26 HFS additionally demonstrates the isochronous balance of mixed carbonate -siliciclastic deposition across the Yates -Capitan reef -rimmed shelf during the initial CS -scale transgression following significant exposure and bypass of sand across the shelf .
This sequence framework is quantitatively analyzed using progradation to aggradation (P /A ) ratios , facies proportions , facies tract dip width , and facies tract bedding angles to evaluate the interplay of eustacy and syndepositional deformation as drivers of stratigraphic architecture . The sequences defined here developed in response to both eustacy and syndepositional deformation , but individual facies distributions and cycle stacking patterns were largely controlled by eustacy ; while facies , cycle , and sequence thicknesses as well as facies bedding angles were locally influenced by syndepositional faulting . A reconstruction of each high frequency sequence and stepwise documentation of post -depositional fault displacement and HFS basinward rotation was generated using the lidar data . This analysis shows that the G23 -G26 HFS developed basinward -dipping depositional topography from the shelf crest to the shelf margin reef . This geometry was largely unaltered by syndepositional faults during individual HFS deposition , but was rotated basinward shortly thereafter by younger fault movement .
The accommodation trends recorded in this largely shelf crest to shelf margin window can be additionally projected into the middle shelf producing zones of the prolific Yates -aged reservoirs on the Northwest Shelf and Central Basin Platform . |