This Master’s research program was undertaken as part of the Hakai Ancient Landscapes Archaeology Project in Heiltsuk and Wuikinuxv Territories on the Central Pacific Coast of British Columbia (BC), Canada. The project tested the utility of applying vibracore technology to sample a shell midden site on Hecate Island on the BC Central Coast. This revealed that the earliest archaeological occupation began approximately 6,000 years ago, continuing into the 16th Century AD. Analysis using 21 radiocarbon dates from six core samples shows the site was repeatedly occupied and accumulated consistently throughout the tested area and extended to a depth of 544 cm depth below surface. Sampled sediments were utilized to evaluate evidence of fisheries resource management through time with reference to the nearby, intensively-studied archaeological site Namu (ElSx-1). Zooarchaeological results show the herring (Clupea pallasii), salmon (Oncorhynchus spp.), rockfish (Sebastes spp.) and greenling (Hexagrammos spp.) were fished persistently and in similar abundances through the occupation of the site. Overall results for vertebrate fauna reveal the total number of specimens is 19,173 and the total number of identified specimens is 6,566. Results also show a consistent harvest of certain shellfish taxa (e.g., mussel and barnacle), however shellfish weight per litre increases through time. When comparing the relative abundance of herring and salmon through time at Namu and EjTa-13, results show that salmon at Namu was more abundant than at EjTa-13. This is likely due to the productivity of salmon in the Namu River adjacent to the site. Alternatively, herring remains were represented similarly between sites indicating the resource was equally desirable at EjTa-13 and Namu. Surprisingly, a large number of very small artifacts of various materials were also recovered (an estimated 550 artifacts per cubic metre of cultural sediments), which indicates that the field and laboratory methods used are especially conducive to the recovery of small items. These results show a persistent and sustainable local fishery through six millennia until the contact period. / Graduate / 2018-12-15

The Dona and Roberts Bay watershed comprises one of the five major watersheds in Sarasota County, Florida. It is connected to the Gulf of Mexico via Venice Inlet. Like many estuaries in the Florida, significant modifications have been made to the drainage basins, principally to the main tributaries. The system has undergone several anthropogenic modifications to enhance water management efforts. Creeks that comprise fresh water input into the system have been dammed in order to inhibit the upstream flow of salt water during the dry season. They are also deepened or lengthened to allow for better drainage. In addition, biogenic activity has also had morphological effects on the system. There are numerous oyster bars, and mangrove forests that impose obstruction to the tidal and river flows. This has resulted in a highly complicated estuary system in terms of flow velocities and sedimentation patterns. The objectives of this study are to quantify the sediment characteristics and deposition-erosion trends and their relationship to flow patterns and other natural and anthropogenic factors within the system. A detailed sedimentary analysis was conducted based on 149 surface sediment samples and 29 drill cores. Spatial distribution of the sediment properties is quite complex, controlled by several interactive factors including; local sediment supply, intensity of the hydrodynamic processes, distribution of oyster bars and mangrove islands, and artificial structures. Sedimentation and erosion is significantly influenced by flood events. In some locations, such as the mouth of the fluvial channels, or the confluence of two creeks, the core data suggest that rapid sedimentation, driven by flood events, is responsible for the development of some of the large shoals. A 2-D depth-averaged circulation model was established for the study area. Many of the natural structures and artificial modifications to the watershed system are incorporated into the model. A close relationship between the flow intensity and sediment characteristics, and therefore, sedimentation-erosion tendency is identified. Remotely sensed data is also incorporated into the study in order to gain an understanding of the development of the estuary system over a ten-year period. Data suggests that the maturation of biogenic organisms that inhabit the system coincides with the development of complex sedimentation patterns.

No description available.

Sedimentary characteristics of grainy non-skeletal tidal flats along windward platform margins have not been described in modern environments and may be misidentified or misclassified in the rock record. This study describes the sedimentology of such an environment to aid in accurate identification and characterization in the ancient. At Shroud Cay, a grain-dominated tidal flat is sheltered from the high energy of the shelf by a ring of cemented Pleistocene and partly indurated Holocene eolianite islands separated by several narrow tidal passes. Depositional texture, environment of deposition and geobody mapping, extensive sediment sampling, and vibracoring have shown that, though the cemented island provide a barrier from the high energy of the shelf, a high degree of tidal energy still occurs behind this barrier as indicated by the overwhelmingly grainy nature of all of the tidal flat sub-environments. Intertidal flats comprise the majority of the tidal flat surface. These flats are characterized by patchy Scytonema mats overlying bioturbated peloid-ooid grainstones to packstones with cemented lithoclasts. Three main tidal channels dissect the tidal flat and allow diurnal flow, one of those tidal channels does not exit the tidal flat but dead-ends behind a cemented Holocene beach dune ridge along the eastern side of Shroud Cay. Peloid-ooid-skeletal grainstone tidal bars and peloid-ooid packstones fill much of the channels. Most of the channels are bordered by low-relief grain-rich packstone levees often capped by red mangroves and algal mats. The interior-most supratidal parts of the flat, often in the lee of the windward Holocene ridge, are covered by a thick (5-~25cm) Scytonema microbial mat underlain by grain-rich ooid-peloid packstones. Ancient grain-dominated carbonate tidal flats and eolianite deposits like Shroud Cay?s are the reservoir rocks in some of today?s largest hydrocarbon fields. We develop a model for the evolution of the grain-dominated tidal flat, document and compare differences between the grain-rich tidal flat and surrounding environments of deposition, and develop a set of criteria for recognition. These criteria can be used to more accurately characterize reservoirs such as the Jurassic Smackover fields, to avoid mis-classification of similar settings, and more effectively produce those reservoirs.