Datasets relating to samples collected from the leeward off-reef area off Wistari Reef

Researchers: Opdyke, Bradley, Dr (collaborator) ,  Ryan, David (principalInvestigator)

Brief description Wistari Reef is a lagoonal platform reef, situated on the Tropic of Capricorn, within the Capricorn and Bunker region of the southern Great Barrier Reef. Surface samples were taken from the leeward off-reef floor to determine the mean grainsize and the sorting coefficient. Within this area the average mean grainsize is ~1.16phi, with an average sorting coefficient of 0.89phi. The sediments of the leeward off-reef floor are relatively mature. Most samples are moderately well-sorted medium sand, and are moderately well-rounded. Patch reefs, and small individual colonial and solitary corals contribute a small amount of coarser material to the sediment.

Lineage Statement: Surface samples were collected from boat transects across Wistari Reef. Deeper samples were obtained by diving. Samples were collected using a hand-held scoop and 600ml plastic bottles. Sediment samples were sieved in order to determine modal particle diameters, and sorting data. Samples were first dry sieved. Sieves of sizes -1.0phi to 2.5phi were stacked and installed on a sieving shaker. Samples were weighed out to approximately 250g, and each sample was sieved for 15 minutes to ensure correct separation of size fractions. Each fraction was then removed from the sieve and weighed. The size fractions 2.5phi, 3.0phi, 3.5phi and 4.0phi were pre-weighed, and wet sieved separately using a low pressure water hose, through smaller micropalaeontological sieves. Sediment textures are expressed in terms of mean grainsize, and sorting coefficient, represented by standard deviation.

Lineage Statement: Scanned histograms are used to highlight the percentage of sediments within each grainsize bracket. The exact percentage figures are not available. Mean grainsize of surface samples parameters: Average mean grainsize (phi), average sorting coefficient (phi), dominant coarse biota, dominant fine biota. Grainsize of surface samples parameters: Sample, latitude (d,m,s), longitude (d,m,s), grainsize brackets (phi), percentage of sediments in grainsize brackets (%).

Notes Credit
Funded by The Australian Research Council (ARC)

Notes Credit
The Australian National University (ANU)

Notes Purpose
To provide an overview of the sedimentary zones of Wistari Reef. Conducted as part of a broader study looking at Holocene production and accumulation of sediments on Wistari Reef.

Data time period: 1998 to 1998

151.83376,-23.47003 151.84068,-23.47284 151.84614,-23.46674 151.83768,-23.46322 151.83376,-23.47003

151.83995,-23.46803

153,-23 153,-24.5 151.5,-24.5 151.5,-23 153,-23

152.25,-23.75

text: westlimit=151.5; southlimit=-24.5; eastlimit=153; northlimit=-23

text: uplimit=18; downlimit=2