Evolution of Coral Rubble Deposits on a Reef Platform as Detected by Remote Sensing

Abstract

An investigation into the evolution of coral rubble deposits on a coral reef platform is assessed using high-resolution remote sensing data and geospatial analysis. Digital change detection analysis techniques are applied to One Tree Reef in the southern Great Barrier Reef by analysing aerial photographs and satellite images captured between 1964 and 2009. Two main types of rubble deposits were identified: (1) rubble flats that are featureless mass accumulations of coral rubble; and, (2) rubble spits that are shore-normal linear features. While both deposits prograde in a lagoon-ward direction, rubble spits move faster (~2 m/yr) than rubble flats (~0.5 m/yr). The volume of rubble, the underlying substrate, the energy regime, and storm frequency control the rate of progradation. Rubble flat occurrence is restricted to the high-energy (windward) margin of the coral reef platform, while rubble spits are distributed reef wide, both in modal high energy and modal low energy regions of the reef. Rubble spit deposition is considered to be a result of enlarged spur and groove morphology of the forereef, whereby wave energy is focused through the enlarged groove formations causing the preferential deposition of coral rubble in particular zones of the adjacent reef flat. One last control is thought to be the elevation of the reef crest whereby lower areas are more prone to rubble flat development. A vertical and ocean-ward accumulation of rubble is occurring on the windward margin of the reef leading to a build-up and build-out of the reef, governing the expansion of the reef footprint. This study shows for the first time the evolution of a coral reef rubble flat and rubble spits over decadal time scales as detected through remotely sensed images spanning 45 years. OPEN ACCESSRemote Sens. 2013, 5

Wave-driven geomorphology of Pacific carbonate coastlines: from landscape to wavelength scale

“…For example, on the fringing Ningaloo reef in Australia, the central reef flat often has a thin layer of sediment that is transported in bedload, but when large storm waves propagate across the reef, they clear the outer and middle reef flat of sediment, leaving it bare (Rosenberger et al, 2019). Storms can also deposit large amounts of coarse sediment on the reef flat that is then reworked across the reef flat and to the beach (Shannon et al, 2013;Blumenstock et al, 1961b). Attempts to identify transport pathways across the reef have included tracking painted cobbles on the fore reef (Kan, 1994), installing passive integrated transponder (PIT) tags in large coral cobbles and relocating them periodically (Ford, 2014;Kench et al, 2017), and using the degree of weathering of sediment with known geographic origins as a proxy for transport time or distance (Dawson et al, 2014;Fellowes et al, 2017).…”

“…Blumenstock et al, 1961a), or deposit a large quantity of coarse sediment on the reef flat that eventually adds to island volume (e.g. Shannon et al, 2013). Tropical cyclones also shape fringing reef morphology, contributing to prominent, crustose coralline algae-covered reef crests and conglomerate platforms that underlie some reef islands (Woodroffe, 2008).…”

Correction: Shannon, A.M.; Power, H.E.; Webster, J.M.; Vila-Concejo, A. Evolution of Coral Rubble Deposits on a Reef Platform as Detected by Remote Sensing. Remote Sensing, 2013, 5, 1–18

“…Due to an oversight by the authors there are a few corrections that are necessary for the publication [1]: Section 2, Study Area. In the part concerning wave climate in the study area (second to last paragraph on Page 3), we need to correct the data period and the reference.…”

“…In the part concerning wave climate in the study area (second to last paragraph on Page 3), we need to correct the data period and the reference. The latter should be Thornborough's thesis [2], which is reference 14 in the original paper [1] On Page 14, in the last paragraph of the discussion, the reference number is incorrect. The sentence reads "Simultaneously, the elevation of the reef flat also increases from the south to the north [10]", but should be:…”

Automated Sensing of Wave Inundation across a Rocky Shore Platform Using a Low-Cost Camera System

“…One of the main advantages of remote sensing techniques is that they allow for the collection of large volumes of data across a wide spatial and temporal domain with relative ease and from an accessible position. They also allow for data collection during extreme conditions and in environments where collecting in situ data would be highly challenging, such as in large storm events (e.g., [10]) and on coral reefs (e.g., [11]). Video remote sensing techniques are one of the more common remote sensing techniques used in the coastal zone and have been used to investigate various processes including: bar morphodynamics [12], wave run-up [13], swash zone flow velocities [14], and the evolution of surf zone rips [15,16].…”