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OCEAN > SOUTHERN OCEAN > MACQUARIE ISLAND

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  • Metadata record for data from ASAC Project 545 See the link below for public details on this project. From the abstract of the referenced paper: Blood was collected for haematological, red cell enzyme and red cell metabolic intermediate studies from 20 Southern elephant seals Mirounga leonina. Mean haematological values were: haemoglobin (Hb) 22.4 plus or minus 1.4 g/dl, packed cell volume (PCV) 54.2 plus or minus 3.8%, mean cell volume (MCV) 213 plus or minus 5 fl and red cell count (RCC) 2.5 x 10 to power 12 / l. Red cell morphology was unremarkable. Most of the red cell enzymes showed low activity in comparison with human red cells. Haemoglobin electrophoresis showed a typical pinniped pattern, ie two major components. Total leucocyte counts, platelet counts, and coagulation studies were within expected mammalian limits. Eosinophil counts varied from 0.5 x 10 to power 9 / l (5%-49%), and there was a very wide variation in erythrocyte sedimentation rates, from 3 to 60mm/h.

  • The RAN Australian Hydrographic Service conducted hydrographic survey HI242 at Macquarie Island in November and December 1996. The main survey areas were Buckles Bay and Hasselborough Bay. Survey lines were also followed from Elliott Reef down the west coast to Langdon Bay and down the east coast to Buckles Bay. The survey dataset, which includes metadata, was provided to the Australian Antarctic Data Centre by the Australian Hydrographic Office and is available for download from a Related URL in this metadata record. The survey was lead by LT M.A.R.Matthews. The data are not suitable for navigation.

  • Metadata record for data from ASAC Project 2212 See the link below for public details on this project. From the abstracts of two of the references: ---------- Ocean Drilling Program hole 504B revealed an ocean crust hydrothermal sulphur anomaly on the dyke-lava transition, with implications for global sulphur sinks. Here we confirm the presence of the anomaly sporadically along 7.5km of dyke-basalt contact on the Macquarie Ridge at Macquarie Island, a 39-9.7 Ma slow-spreading setting. Background contact-zone pyrite S contents average 1845 ppm across ~50 m. However zones of small-scale brittle faulting that commonly occur on and above the dyke-basalt contact average between 5000 and 11000 ppm S (20-30 m widths). These consist of steep ridge-parallel faults and fault splays on the contact, overlain by up to 50m of linked pyritic fault trellis. The contact zone faults are haloed by disseminated pyrite-chlorite, cross-cut by quartz-chlorite-sphalerite and epidote-cemented breccias, containing evidence of turbulent flow. The structural control on sulphur deposition is attributed to the active extensional slow spreading setting. With increasing extension, diffuse mixing across the contact was replaced by channelised flow and dynamic mixing in fault arrays. The magnitude of the dyke-lava transition sulphur sink must be reassessed to take account of this heterogeneity. ---------- There are only a handful of known hydrothermal sulfate occurrences from the mid-ocean ridge crust sub-surface, despite predictions that they should be common because of the imbalance between sulfur concentrations in venting MOR hotsprings, and that of recharging seawater. This deficit indicates that sub-surface sulfate deposition could be a globally important sulfur cycle sink. Therefore any new occurrences add considerably to the information base on sulfate in this environment. An important hydrothermal sulfate occurrence is preserved in ~10 Ma MOR crust on the east coast of Macquarie Island, formed during very slow oblique spreading prior to transition to a magmatic strike-slip plate boundary. The sulfate occurs mainly as white gypsum veins and breccia cement associated with a major fault zone 400m south of Nuggets Point. The site is in the amphibolite facies sheeted dyke and gabbro screen hanging wall of a major northwest-trending graben, itself filled with sub-ziolite facies basaltic breccias and lava flows. The sulfate veins occur as several 2-5m wide vein complexes, with surrounding vein networks over several hundred metres. Veins are strongly associated with oblique-sinistral jogs on a N to NNE-trending fault zone, here termed the Nuggets fault. This fault is intruded by thin, weakly metamorphosed, vesicular sheeted dykes (forming a greater than 30m wide zone) interpreted to have developed contemporaneously with the nearby graben, Gypsum is mainly in the amphibolite facies rocks and the younger dykes, but also occurs as thin gape-fill in dykes of the younger volcanic graben. These field relations indicte that the sulfate veins were emplaced contemporaneously with graben formation and infill, approximately 200m below the sea floor. The host fault zone is contiguous with mapped graben offsets, and is interpreted as an oblique transfer fault. Secondary epidote and quartz-chalcopyrite veining, together with subsequent chlorite-pyrite alteration, predate sulfate, and suggest early hydrothermal upflow conditions. These are cut by vein complexes which display anhydrite relics within foliated gypsum plus or minus pyrite veins surrounded by marginal vein networks of zeolite-gypsum-calcite. These assemblages require central temperatures of greater than 150 degrees C, with a rapid gradation in outer veins to cooler conditions, perhaps less than 100 degrees C. These features imply general cooler recharge conditions; our previous work has shown that this involved a complex history of sub-surface microbial interaction. These field and mineralogical relations provide one predictive tectonic context for the deposition and style of hydrothermal sulfate in extending MOR crust. Sulfate fluid is strongly fault channeled, and rather than occurring in graben boundary faults, deposits precipitates preferentially in transfer faults under-going limited magmatic activity on the graben edge. A description of the fields in this dataset: m from start: metres measured over the ground between sample points. Easting mE, and Northing mE: estimated position relative to the AMG grid used in the 1;10000 mapping series, Mineral Resources Tasmania, using a horizontal datum of WGS 1984. Map date of production, August 1997.

  • The RAN Australian Hydrographic Service conducted hydrographic survey HI176 at Macquarie Island in December 1993. The main survey area was adjacent to the north-east coast between North Head and The Nuggets. Survey lines were also followed part way down the west coast of the island and in the vicinity of Judge and Clerk Islets and Bishop and Clerk Islets. The survey dataset, which includes metadata, was provided to the Australian Antarctic Data Centre by the Australian Hydrographic Office and is available for download from a Related URL in this metadata record. The survey was lead by LT A.J.Withers. The data are not suitable for navigation.

  • The AADC (Australian Antarctic Data Centre) is in the process of converting all internally held spatial datasets to the ITRF2000 horizontal datum. This consolidated dataset consists of surveys HI623_alatB_gg, HI625_alatB_GG, HI632_alat_B_gg, HI632_alat_C_gg, LADSII_MMI20756_HSDB_T0001_SD_100029052_op, LADSII_MMI20756_HSDB_T0001_SD_100029053_op, LADSII_MMI20756_HSDB_T0001_SD_100029054_op converted to ITRF2000 horizontal datum with Z conversion values for multiple height datums. The data was provided to the AAD by Paul Digney of Jacobs consulting in March 2021. Included survey datasets: • HI623_alatB_gg • HI625_alatB_GG • HI632_alat_B_gg • HI632_alat_C_gg • LADSII_MMI20756_HSDB_T0001_SD_100029052_op • LADSII_MMI20756_HSDB_T0001_SD_100029053_op • LADSII_MMI20756_HSDB_T0001_SD_100029054_op All data are in horizontal datum ITRF2000 and have been combined into a single ESRI geodatabase feature class titled AHS_Surveys_Macca_ITRF2000. Attribute data shows quality information, conversion factors (shift in metres) for multiple datums and the MSL orthometric height: Column Name Alias Meaning Easting Easting Easting ITRF2000 Northing Northing Northing ITRF2000 LAT_to_GRS LAT_to_GRS LAT (Chart Datum) to GSR80 LAT_to_Mac LAT_to_Mac LAT to Macca MSL Z_To_GRS80 Z_To_GRS80 Height to the Ellipsoid Z_To_Macca Z_To_Macca Local MSL orthometric height Vertical_U Vertical_U How good is the Vertical Position Horizontal Horizontal How good is the Horizontal Position Uncertaint Uncertaint Uncertainty Comments Depth_Comm Depth_Comments Vertical uncertainty ranges from 0.5 to 1.2 m and horizontal uncertainty ranges from 2 to 5.5 m. Null values indicate unknown uncertainty. See the attached document ‘Metadata_Record_Macqaurie Island Final.xlsx’ for further details.

  • Ship-based observations of birds, seals and whales from the original 'ANARE Bird Log' books have been recovered into a single repository of sightings and associated abiotic information. ANARE (Australian National Antarctic Research Expeditions) is the historic acronym for these voyages. A few voyages have been included that were not part of ANARE but have Australian observers or volunteer observers. Voyages start from the 1947/48 austral season up to 1982/83 with an average of 3 voyages per season. There are a few voyages where there is no data. It is not known if either no bird observations were undertaken during this period or that the bird logs exist if observations were undertaken. Current counts are birds, seals and whales Observing platforms include the following ships - Wyatt Earp, Tottan, River Fitzroy, Norsel, Kista Dan, Thala Dan, Magga Dan, Nella Dan, Lady Franklin and Nanok S and a single voyage from the private yacht Solo. The quality and quantity of abiotic data associated with observations such as air temperature, sea ice cover etc vary immensely from voyage to voyage. Where possible this data has been entered. This dataset contains very little information on estimates of survey effort and cannot be used to derive useful presence/absence spatial coverages of species during this period. It is purely sighting data only.

  • This metadata record is a modified child record of an original parent record originating from custodians of data associated with Geoscience Australia (The identifier of the parent record is ANZCW0703009248, and can be found on the Australian Spatial Data Directory website - see the URL given below). Taken from the report: A bathymetric grid of the Heard Island-Kerguelen Plateau Region (Longitudes 68 degrees E - 80 degrees E, Latitudes 48 degrees S - 56 degrees S) is produced. In doing so, the individual datasets used have been closely examined and any deficiencies noted for further follow up or have been rectified immediately and the changes documented. These datasets include modern multibeam data, coastline data obtained from the World Vector Shoreline, echosounder data from research, fishing and Customs vessels and satellite derived bathymetric data. A hierarchical system was employed whereby the best and most extensive datasets were gridded first and applied as a mask to the next best dataset. A new masking grid would be formed from these datasets to pass non-overlapping data in the next best dataset. This procedure was employed until finally the satellite data were masked. All the various levels of masked data were then brought together by the gridding algorithm (Intrepid - Desmond Fitzgerald Associates) and an ERMapper format grid produced. A grid cell size of 0.005 degrees (nominal 500m) was used with many iterations of minimum curvature gridding and several passes of smoothing. The final grid is available in ERMapper, ArcInfo and ASCII xyz formats.

  • The only work that went ahead as part of this ASAC project was to look at Penguins restraint and stress level (see the referenced paper below). From the paper: During most research on penguins it is necessary to temporarily immobilise the birds at some time (to weigh, mark, or attach instruments). Although many penguin species seem unconcerned about a human's presence, a single approaching person has been shown to increase the birds heart rate, suggesting that the animal is aware and may be stressed. Corticosterone is one of the hormones regulating the stress reaction in birds, and in turn regulates that stress caused by immobilisation. As captured and bag restrained Adelie penguins show a three fold increase in heart rate, we can presume that this is a very stressful immobilisation technique. Restricting the stress reaction is particularly important during the breeding season to avoid nest desertion, or loss of eggs and chicks. The subject of this paper is to present a less stressful method for restraining penguins. 38 mature, male Gentoo penguins in good physical condition were used to test bag restraint methods. Resting animals were caught on the Macquarie Island Isthmus. 59 animals were used to test the effect of hood restraint methods. There was a significant increase in corticosterone concentrations in the blood of bag restrained penguins within 10 minutes of restraint. Between 10 and 15 minutes, further changes were not significant. After 20 minutes, however, there was a second significant increase, when compared to the levels at 15 minutes. Upon release all birds were unconscious; they then showed symptoms of hysteria, such as disorientation and shaking of the head. Corticosterone levels in the blood of hooded penguins rose significantly after 5 minutes. After 10 minutes, the mean concentration showed a tendency to decrease, when compared to the 5 minute levels. This, however, did not differ significantly to concentrations immediately after restraint. After 20 minutes concentrations rose again, and were again significantly higher than at the same time of restraint and after 15 minutes. Both groups showed the same levels of corticosterone upon restraint. Hood restraint led overall to a lower increase in corticosterone levels than restraint with a bag. After 5, 10, 15 and 20 minutes, statistically significant lower levels in the blood were detected in hood restrained birds. The penguin's reaction to both restraint methods was identical in two respects: There was no significant increase in corticsterone concentration between 10 and 15 minutes. Secondly, concentrations were significantly higher after 20 minutes than at 15 minutes.

  • Australian Bird and Bat Banding Scheme Bird Banding records from the Australian Antarctic Territory and Heard Island, a subset of banding and recovery records from within Australian Antarctic Territory and Heard Island. The Australian Government under the auspices of the Australian Bird and Bat Banding Scheme (ABBBS) manages the collation of information on threatened and migratory bird and bat species. The information provided spans from 1953 to the present, and contains over 2 million records. This set comprises records of banding and recovery in the Australian Antarctic territory. Records are also included if the bird was recovered or banded outside this region. The ABBBS site is at http://www.environment.gov.au/science/bird-and-bat-banding.

  • Metadata record for data from ASAC Project 829 See the link below for public details on this project. From the abstract of one of the referenced papers: During the intensive field operations period (November 15 to December 14, 1995) of the First Aerosol Characterisation Experiment (ACE 1) cold front activity was generally above average, resulting in below average temperatures, pressures, and rainfall. The principal cause was the presence for much of the experiment of a long wave trough. This trough was mobile, traversing the ACE area during the project, with some warm anomalies evident in teh areas under the influence of the long wave ridges. There is evidence of greater convective activity than normal, possibly leading to a slightly deeper than average mixing layer. A greater west to northwesterly component to the air flow than average during November appears to have led to higher than average concentrations of radon and particles in the clean, marine or 'baseline'; sector at Cape Grim (190 degrees to 280 degrees). This is likely to have resulted from inclusion of continental air from western parts of the Australian mainland in the baseline sector winds. Although aerosol-bound sulfur species were generally near their normal concentrations across the ACE 1 area, the overall pattern including atmospheric dimethylsulfide suggest slightly higher than usual sulfur species levels in the southern part of the region and lower concentrations in the northern part during November. This could be related to changes in marine biogenic productivity, air-sea exchange, or atmospheric removal. In December, the changing long wave pattern brought an increase in south and southwesterly flow over the entire region. The baseline sector became less affected by continental species, but it appears that the colder conditions brought by this pattern have led to lower than usual atmospheric concentrations of biogenic species, as the region went into one of the coldest summers on record.