In this report four sediment types based on particle size distribution, organic content, 
and faunal assemblages are described from core samples taken at Ramshorn Spit, 
eastern Florida Bay. The basic types were: (1) very thin discontinuous shelly 
packstones, representing storm deposits; (2) thin continuous basal shelly packstones, 
the initial marine deposit on bedrock; (3) muddy wackstones, of variable thickness, 
deposited in the presence of seagrass; and (4) very thick, fairly laminated fine 
mudstones, with very sparse fauna, representing transported sediments out of 
suspension. These classifications were confirmed by discriminant analysis which 
showed that these sediment layers were correctable between cores, indicating a 
change in stratigraphy southwestward from the spit and bank junction. The author 
concludes that Ramshorn Spit, throughout its depositional history, seems to have been 
accreting outward into the surrounding 'lake' by means of a current-transported mud 
fraction; sediments are subsequently stabilized by turtle grass cover. 
1985 0 
Holliday, V. E., and J. M. Parks (1985) Mechanisms of deposition of a carbonate mud spit; 
Ramshorn Spit, eastern Florida Bay. Am. Assoc. Petrol. Geol. Bull. . 69:266. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] The turtle 
grass (Thalassia testudinum) community has a significant influence on sedimentation in 
Florida Bay, but the roles other processes may play in the buildup of mudbank and spit 
sediments are poorly understood. Samples from cores taken from Ramshorn Spit and 
Ramshorn Shoal were classified into 4 basic types on the basis of particle size 
distribution, organic content, and faunal assemblages. In order of increasing volumetric 
importance they are: (1) very thin, discontinuous shelly packstones, representing 
overbank or storm deposits; (2) thin, continuous basal shelly packstones, the initial 
marine deposit on the Pleistocene bedrock surface; (3) muddy wackestones, of variable 
thickness, deposited in the presence of a seagrass community; and (4) very thick, 
faintly laminated fine mudstones, with very sparse fauna, representing weak current- 
transported sediments settling out of suspension. Discriminate function analysis 
confirms the classifications and shows that these sediment layers are indeed 
correctable between cores. Interpretation of the core logs from Ramshorn Spit 
indicates a definite change in stratigraphy southwestward from the spit and bank 
junction to the tip of the spit itself. The different sediment layers show a small but 
significant inclination to the southwest. Throughout its depositional history, Ramshorn 
Spit seems to have been actively accreting outward into the surrounding 'lake' by 
means of a current-transported fine mud fraction. After settling out at the growing tip 
of the spit, the sediments are subsequently stabilized at some later time by a turtle- 
grass cover. 
1985 
Kieber, D. J., and K. Mopper (1987) Photochemical formation of glyoxylic and pyruvic 
acids in seawater. Mar. Chem. . 21:135-49. 
Glyoxylic and pyruvic acids were formed when filter-sterilized seawater was exposed 
to solar radiation. Samples were collected in 1985. Production rates varied from 
samples collected from distinctly different regions of the sea. Humic-rich seawater 
from Florida Bay exhibited net photochemical production rates (glyoxylate, 27.5 nM W- 
h' 1 nr 2 ; pyruvate, 12.9 nM W-h' 1 m' 2 ) that were significantly greater than net 
production rates for humic-poor water (glyoxylate, 3.1 nM W-h' 1 nr 2 ; pyruvate, 1.8 
nM W-h' 1 m' 2 ) collected in the Gulf Stream. When seawater was not filtered, the 
concentrations of glyoxylate and pyruvate were found to undergo diurnal variations 
resulting from an imbalance between biological and photochemical processes. A depth 
profile of the glyoxylate concentration from several oceanic stations showed a 
pronounced daytime maximum in the upper 10 m; this finding is consistent with 
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