Brief description
A gravity core (GC11) was collected from a depth of 502 mbsl within the Capricorn Channel, southern Great Barrier Reef (GBR). The data from stable isotopes of Globigerinoides ruber were analysed to allow a preliminary understanding of the hemipelagic sedimentary environment over the last glacial / interglacial cycle. The results suggest that the core reaches the Last Glacial Maximum (LGM) at ~30cm depth. From matching the 18O G. ruber curve with Martinson et al. (1987), 4 glacial cycles can be determined, incorporating Marine Isotope Stage (MIS) 1 through to MIS 11. Isotopically heavier 18O values at ~460cm, ~345cm, 150cm, and 30cm correspond respectively to MIS 10, MIS 8, MIS 6 and the LGM. The d13C shows a trough lagging behind the 18O high during the glacial, although there are considerable fluctuations between MIS 8 and 6.Lineage
Maintenance and Update Frequency: notPlanned
Statement: Samples for foraminifera picking were dried in the oven at 60oC before being re-soaked in distilled water. Samples were then wet sieved through a series of four mesh sizes before the size fractions were transferred to drying trays. After drying foraminifera were picked from under microscope for the large size fractions of >300 µm and >400µm. 10-15 white Gs. ruber were hand picked to give a total sample weight of 180-220µg for isotope analysis. The samples were washed in methanol and ultrasonicated for 30 secs to remove any surface and internal particles. The samples were analysed at the Research School of Earth Science, Australian National University, using an automated individual carbonate reaction (Kiel) device coupled with a Finnigan MAT-251 mass spectrometer.
Statement: Both 18O and 13C values are provided for 5cm, 10cm, 15cm, 20cm and then every 10cm down the core to a depth of 560cm. Mass spectrometer was run concurrently with international standards NBS-19 and NBS-18, and has a very small analytical error.
Parameters: Depth in core (cm), oxygen-18 G. ruber (parts per thousand), carbon-13 G. ruber (parts per thousand).
Notes
CreditFunded by The Australian Research Council (ARC)
Credit
Funded by The Australian National University (ANU) Faculties Research Grant Scheme
Funded by The Australian National University (ANU) Faculties Research Grant Scheme
Purpose
To determine the sedimentological variations with sea-level over the last glacial/ interglacial cycle in the Capricorn Channel. Very little previous work has been undertaken within this area.
To determine the sedimentological variations with sea-level over the last glacial/ interglacial cycle in the Capricorn Channel. Very little previous work has been undertaken within this area.
Issued: 27 06 2007
Data time period: 1997 to 1997
text: westlimit=151.5; southlimit=-24.5; eastlimit=153; northlimit=-23
text: uplimit=502; downlimit=502
Subjects
51200000 |
AMOEBOIDS |
BIOLOGICAL CLASSIFICATION |
EARTH SCIENCE |
Foraminifers |
Foraminifera |
Foraminiferans |
Foraminiferida |
Isotopes |
OCEAN/LAKE RECORDS |
PALEOCLIMATE |
PROTISTS |
amount_of_carbon-13_isotope_g._ruber |
amount_of_oxygen-18_isotope_g._ruber |
core_depth |
environment |
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Other Information
(ANU_Bostock_GC11_1_data.xls)
global : 2b6c31c0-2465-11dc-95fb-00188b4c0af8
Identifiers
- global : cdeb6910-246b-11dc-95fb-00188b4c0af8
