is loose, not stabilized by invertebrate "turfs", and may be more 

 easily moved by currents. The lack of elongation suggests that 

 current scour is not a dominant cause . The pockmarks are most 

 likely complex features with multiple causes. 



In summary, the inner shelf of Maine, in the areas we have 

 observed by remote techniques and by direct submersible 

 reconnaissance, is a patchwork mosaic of sedimentary 

 environments. The greatest variability is above 60-90 m depth, 

 that is above the depth of the early Holocene lowstand and 

 paleo-wave base. Variability on the scale of meters and tens of 

 meters is evident. Planning for future sediment grab sampling 

 and biological sampling should consider this; one random sample 

 per square kilometer does not give a fair assessment of the 

 variability. In much of the area the sediments are a palimpsest 

 of Quaternary sedimentary regimes overlain by modern processes. 

 Glacial and deglacial, subaerial, deltaic, and shoreline 

 processes may have acted on a specific locale before the present 

 marine conditions took hold. We also have gained a better 

 appreciation for the interaction between biological and 

 geological processes here. Carbonate productivity around 

 shorelines and shallow shoals has resulted in a carbonate halo. 

 Bioturbation and microbial production of gas are important 

 factors in basins. In the reverse application, the better 

 definition of this mesoscale variability in geologic environments 

 should be of use to biological oceanographers in evaluating the 

 Maine inner shelf ecosystems. Finally, the integration of remote 

 sensing, sampling, and direct observation and experimentation 

 from submersibles has allowed a more complete determination of 

 the distribution of and processes acting in these sedimentary 

 environments . 



ACKNOWLEDGMENTS 



The submersible-based research described above has been 

 supported by NOAA's National Undersea Research Program based at 

 the University of Connecticut, Avery Point. This project has 

 also been supported by the NSF EPSOR Program, by the Maine-New 

 Hampshire Sea Grant College Program, U.S. Minerals Management 

 Service, and the Maine Geological Survey. We would like to 

 acknowledge the essential assistance of the Harbor Branch 

 Foundation, operators of the Johnson Sea Link , and the Marfab 

 organization, operators of the Delta . We especially acknowledge 

 the many hours of excellent support and advice from Richard 

 Slater and Douglas Privet. Others who have contributed to this 

 effort include R. Craig Shipp, William Duffy, Stephen M. Dickson, 

 Weiming Tu, and Dr. Edward M. Laine. 



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