--> ABSTRACT: Effect of Rates of Relative Sea-Level Change and Setting on Carbonate Depositional Sequences, by E. K. Franseen, R. H. Goldstein, and M. R. Farr; #91021 (2010)
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Effect of Rates of Relative Previous HitSeaNext Hit-Previous HitLevelNext Hit Change and Setting on Carbonate Depositional Sequences

FRANSEEN, EVAN K., ROBERT H. GOLDSTEIN, and MARK R. FARR

Sequence stratigraphy, quantitative (pinning point) relative Previous HitseaNext Hit-Previous HitlevelNext Hit curves and magnetostratigraphy indicate how rates of Previous HitseaNext Hit-Previous HitlevelNext Hit change and setting controlled accumulation and geometries of Upper Miocene carbonates in SE Spain. Five 3rd- and 4th- order depositional sequences (DS1A, DS1B, DS2, DS3, TCC) formed with superimposed higher frequency events.

DS1A-DS1B, cooler water ramps, represent sediment bypass across steep paleoslopes to toes of slopes. Accumulation rates decreased from greater than 15.6 cm/ky to approx. 2 cm/ky and overall relative Previous HitseaNext Hit Previous HitlevelNext Hit rose at 17-21.4 cm/ky. Higher frequency Previous HitseaNext Hit-Previous HitlevelNext Hit rates were approx. 111 to greater than 260 cm/ky producing onlapping and draping, fining- (deepening-) upward cycles. Decreasing accumulation rates resulted from decreasing surface area for shallow-water production and drowning of shallow-water substrates. The bypass "ramp" processes precluded typical Previous HitsystemsNext Hit tract and parasequence development.

Basal and upper DS2 lowstand reef megabreccias reflect deposition during rapid falls, perhaps with short lowstand durations.

DS3 reefs (warmer conditions) formed where Previous HitseaNext Hit Previous HitlevelNext Hit coincided with gently sloping substrates. During the initial rise, rates were too rapid (>>19 cm/ky) to deposit a transgressive Previous HitsystemsNext Hit tract. Later reefs formed forced regressive Previous HitsystemsNext Hit Previous HittractsNext Hit because rates of fall were less than or equal to 10 cm/ky. Slow progradation (0.39-1.45 km/Ma) resulted from the minor bank top, falling Previous HitseaNext Hit Previous HitlevelNext Hit, and land-derived excess nutrients and siliciclastics.

Topography-draping depositional sequences (TCC) formed where gentle topography and Previous HitseaNext Hit Previous HitlevelNext Hit coincided. The rapid Previous HitseaNext Hit-Previous HitlevelNext Hit changes (130-240 cm/ky) for TCC sequences prevented typical Previous HitsystemsNext Hit tract development.

These new results quantify settings and rates of Previous HitseaNext Hit-Previous HitlevelNext Hit change that prevent typical Previous HitsystemsNext Hit Previous HittractsNext Hit and produce forced regressive Previous HitsystemsNext Hit Previous HittractsTop. 

AAPG Search and Discovery Article #91021©1997 AAPG Annual Convention, Dallas, Texas.