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The study of modern hurricane deposits is useful both in identifying ancient hurricane deposits in the rock record and predicting patterns of deposition and erosion produced by future storm events. Hurricane deposits on carbonate platforms have been studied less frequently than those along continental coasts. Here we present observations of the characteristics of deposition and scour caused by Hurricane Irma on Little Ambergris Cay, a small uninhabited island located near the southeastern edge of the Caicos platform in the Turks and Caicos Islands. Hurricane Irma passed directly over Little Ambergris Cay on September 7, 2017 as a Category 5 hurricane. We described and sampled multiple types of hurricane deposits and determined that the washover fans were the best sedimentological records for hurricane conditions, as they were subject to very little reworking over time. We compared different model predictions of storm tide and wave height with eyewitness reports and distributions of scour. Examining the washover fans allowed for the construction of a conceptual model for hurricane deposits formed in a high‐energy storm event on a carbonate platform. Characteristics of the washover fans were their small size, the lack of sedimentary structures, and very well‐sorted sediment. The size and distribution of carbonate boulders eroded and transported by the storm are consistent with depth‐averaged flow velocities in the range of 1.5‐5.3 m/s. The strength of the storm and the low‐lying topography, distinct features of a carbonate platform setting, contributed to high levels of sediment bypass and high flow velocities, resulting in small, unstructured deposits.
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Surface Collections and Excavations: Case Studies from Moho Cay, Wild Cane Cay, and the Paynes Creek Salt Works
Surface collections can help date sites, provide information for excavations, or be used to address various questions about the site. Establishing a grid for surface collection, using mapped architecture as a basis for collecting material, or individually mapping surface finds, refines the context and enhances chances of evaluating spatial patterns of artifacts that define culture. Three different surface collection strategies are discussed for places on the coast of Belize, including Moho Cay, Wild Cane Cay, and the Paynes Creek Salt Works.
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- Award ID(s):
- 1826653
- PAR ID:
- 10526528
- Publisher / Repository:
- Canadian Latin American Archaeology Society
- Date Published:
- Journal Name:
- CLAAS Notes
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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