Table 3 Global estimates of shallow-water reefs, shelf edge reefs and Halimeda bioherms as extrapolated from the proportions of the different features relative to the Holocene reefs of the GBR.
From: New constraints on the postglacial shallow-water carbonate accumulation in the Great Barrier Reef
Study | This study | ||||
|---|---|---|---|---|---|
Feature | Global Holocene reefs | Global shelf-edge reefs (from GBR mass ratio) | Global shelf-edge reefs (from GBR area ratio) | Global Halimeda mounds (from GBR mass ratio) | Total postglacial CaCO3 |
Dataset/observations/parameters | Area in Spalding et al.56, other parameters from this study | This study, shelf edge/Holocene mass adjustment factor = 18% | This study, shelf edge/Holocene area adjustment factor = 22% | McNeil et al.27 | Global Holocene + shelf-edge + Halimeda mounds |
Timing (ka BP) | 8 to 0 | 19 to 10 | 19 to 10 | 8 to 0 | 19 to 0 |
Reef area (km2) | 284,000 | 51,120 | 62,480 | 57,295 | 398,095 |
Average reef thickness (m) | 15 | 15 | 15 | 8 | 5–15 |
Total volume > 130 mbsl (km3) | 4260 | 767 | 937 | 481 | 5593 |
Porosity (%) | 35 | 35 | 35 | 58 | 35–50 |
Net CaCO3 volume (km3) | 2769 | 498 | 609 | 202 | 3525 |
Density (kg m−3) | 2930 | 2930 | 2930 | 2930 | 2930 |
Net CaCO3 mass (Gt CaCO3) | 8113 | 1460 | 1785 | 592 | 10,328 |
Net CaCO3 accumulation rate (Gt CaCO3 y−1) | 1.0 | 0.2 | 0.2 | 0.1 | 0.6 |
Mass areal accumulation (kg m−2) | 28,568 | 28,568 | 28,568 | 10,337 | 25,944 |
