platform, keep-up and catch-up, are differentiated here. (1) A keep-up 

 carbonate highstand platform is interpreted to represent a relatively rapid 

 rate of accumulation that is able to keep pace with periodic rises in relative 

 sea-level. A keep-up carbonate is characterized mounded/oblique stratal 

 configuration at the platform/bank margin and in places on the platform. (2) 

 A catch-up carbonate highstand platform is interpreted to represent a 

 relatively slow rate of accumulation that is characterized by micrite-rich 

 parasequences and pervasive early submarine cementation at the platform 

 margin. A catch-up carbonate displays a sigmoid depositional profile at the 

 platform/bank margin. 



At the formation of a type 1 sequence boundary, where the rate of 

 eustatic fall is interpreted to be greater than subsidence at the 

 platform/bank margin, two major processes occur: (1) local- to-regional slope 

 front erosion and (2) subaerial exposure of the shelf and major seaward 

 movement of the regional meteoric lens. At a large-scale type 1 sequence 

 boundary, sea- level may fall from 75 to 100 m or more and for an extended 

 period of time. When this occurs, the meteoric lens becomes established over 

 the shelf for a long time, and its influence extends well into the subsurface. 

 If there is sufficient rainfall and a permeable section with mineralogically 

 unstable grains, significant solution will occur over the shelf in the shallow 

 portion of the underlying highstand carbonate platform. Precipitation of 

 phreatic cements will occur deeper or downdip in the section. At a small- 

 scale type 1 sequence boundary, where sea- level falls less than about 100 m 

 and for a short period of time, the meteoric lens becomes less well 

 established. It remains in a shallow position on the shelf, causing less 

 extensive solution. Mixing and hypersaline dolomitization may be important 

 processes during the late highstand and continuing through the formation of 

 either a large- or small-scale type 1 sequence boundary. At a type 2 sequence 

 boundary, in which the rate of eustatic fall is interpreted to be less than 

 the rate of subsidence at the platform/bank margin, the inner-platform 

 peritidal and outer-platform shoal areas will be exposed. The dominant 

 meteoric effect will be in the inner-platform areas. 



During sea- level lowstands, three types of carbonate deposits are 

 recognized: (1) allochthonous material derived from erosion of the slope 

 (i.e., debris sheets and allodapic carbonate sands): (2) autochthonous wedges 

 deposited on the upper slope during type 1 sea-level lowstands; and (3) type 2 

 platform/bank margin wedges. In addition, given the appropriate climatic and 

 hydrographic conditions (i.e., evaporation exceeds influx, and basin is 

 restricted) , evaporite lowstand wedges may occur associated with either type 1 

 or type 2 sequence boundaries. During evaporitic lowstands, hypersaline 

 dolomitization, evaporite replacement, and solution may occur in associated 

 carbonate highstand platforms. Siliciclastic lowstand deposition will occur 

 in areas where an undip-source terrain is available. (Author). 



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