Spur and groove (SaG) morphology is a common ornamentation of reef-armored Holocene carbonate platform margins. Composed of margin-normal promontories constructed of coral framestone, termed “spurs”, interleaved with similarly orientated gullies, “grooves”, this morphology varies based on a host of physical controls. Primarily, the surrounding oceanographic conditions as well as the size and shape of the platform the SaG is encompassing, directly influence the development and organization of SaG. Since grooves act as conduits for carbonate sediment transport, this study seeks to examine the relationship between SaG organization dictated by platform size and shape and how that in turn influences platform-top sedimentation. The analysis reveals trends that suggest platform shape plays a larger role than platform size in allowing highly organized SaG to develop on multiple margins around the platform. In turn, those trends would suggest these sites to have more stable platform top sediment deposits. However, many variables go in to the creation and maintenance of platform top cays. While this study enhanced the current understanding of how oceanographic conditions influence SaG development and organization, expanding on the concepts and results found in this study coupled with coring data of SaG and platform-top cays, could further link the connection between SaG and sediment transport.

This thesis examines functional relationships between the morphologic, hydrodynamic, ecological and sedimentological characteristics of the Warraber reef platform, an inter-tidal reef island system, Central Torres Strait, Australia (10[degrees] 12??? S, 142 [degrees] 49??? E). Hydrodynamic and sediment-transport experiments were conducted on the reef flat using current meters, water level recorders and directional sediment traps. Results showed dominantly SE flows during the dry season and more variable NW to SE flows during the wet season. Topography and reefal water levels modulated the direction and strength of currents and the generation of wind-waves on the reef flat as well as the passage of waves over the reef rim. These hydrodynamic conditions are sufficient to induce significant transport of moderately fast to slow settling sediment (&gt-5.25 symbol psi) on the reef flat, though the platform as a whole is a relatively closed transport system. Carbonate production was estimated based on the key ecological variables of live assemblage distribution and cover. Overall, only 24% of the reef flat was occupied by carbonate-producing organisms. The average estimated carbonate-production rate for the reef was 1.6 kgm -2y-1 (0.07-4.37 kgm-2y-1). Production is dominated by coral (73%), with subordinate proportions contributed by coralline algae (19%). And molluscs, foraminifera and Halimeda (&lt4%) though actual reef-flat sediments did not reflect this potential. Instead, they were dominated by molluscs (35-55%), coralline algae (16-26%), coral (8-13%), Halimeda (7-8%) and foraminifera (5-10%). Differential rates of carbonate to sediment conversion meant the reef-platform sediments were more closely related to the cover of live organisms than to the contribution of carbonate production by each parent organism. The settling properties of the least altered particles of the five commonest constituents were measured and these provided the basis for an eco-sedimentological model of the reef-platform system. Modelled textures were compared to the actual textures, indicating the degree of textural alteration resulting from a combination of biological and physical processes, including sediment production, hydraulic sorting and mechanical breakdown. This analysis, integrated with the hydrodynamic, exposure and other data, was used to determine reef-platform surface-sediment sources, sinks and transport pathways. In using both the textual and constituent compositional properties of sediments, as well as information on local biological and physical processes, the model approach developed offers progress towards an integrative, interdisciplinary analysis of carbonate environments.

This thesis examines functional relationships between the morphologic, hydrodynamic, ecological and sedimentological characteristics of the Warraber reef platform, an inter-tidal reef island system, Central Torres Strait, Australia (10[degrees] 12??? S, 142 [degrees] 49??? E). Hydrodynamic and sediment-transport experiments were conducted on the reef flat using current meters, water level recorders and directional sediment traps. Results showed dominantly SE flows during the dry season and more variable NW to SE flows during the wet season. Topography and reefal water levels modulated the direction and strength of currents and the generation of wind-waves on the reef flat as well as the passage of waves over the reef rim. These hydrodynamic conditions are sufficient to induce significant transport of moderately fast to slow settling sediment (&gt-5.25 symbol psi) on the reef flat, though the platform as a whole is a relatively closed transport system. Carbonate production was estimated based on the key ecological variables of live assemblage distribution and cover. Overall, only 24% of the reef flat was occupied by carbonate-producing organisms. The average estimated carbonate-production rate for the reef was 1.6 kgm -2y-1 (0.07-4.37 kgm-2y-1). Production is dominated by coral (73%), with subordinate proportions contributed by coralline algae (19%). And molluscs, foraminifera and Halimeda (&lt4%) though actual reef-flat sediments did not reflect this potential. Instead, they were dominated by molluscs (35-55%), coralline algae (16-26%), coral (8-13%), Halimeda (7-8%) and foraminifera (5-10%). Differential rates of carbonate to sediment conversion meant the reef-platform sediments were more closely related to the cover of live organisms than to the contribution of carbonate production by each parent organism. The settling properties of the least altered particles of the five commonest constituents were measured and these provided the basis for an eco-sedimentological model of the reef-platform system. Modelled textures were compared to the actual textures, indicating the degree of textural alteration resulting from a combination of biological and physical processes, including sediment production, hydraulic sorting and mechanical breakdown. This analysis, integrated with the hydrodynamic, exposure and other data, was used to determine reef-platform surface-sediment sources, sinks and transport pathways. In using both the textual and constituent compositional properties of sediments, as well as information on local biological and physical processes, the model approach developed offers progress towards an integrative, interdisciplinary analysis of carbonate environments.