Twenty-six marine and lacustrine sediment cores were taken from Windmill Islands during the 1998/99 season. They have been analysed for physical, chemical and biological parameters by a multidisciplinary team under ASAC project 1071. The download file contains 12 Excel spreadsheets of data.

Amery Ice Shelf AM06 borehole drilled early January 2010. Sub-shelf water profiling measurements conducted over a period of a few days. Partial video recording of borehole walls and sea floor benthos. Collection of targeted ice core samples. Sediment sample collected from sea floor. Long term monitoring instruments installed (thermistors in ice, 3 x CTD in ocean cavity). This is a parent record - see the child records for further information, and access to the data. Some general readme documents are available for download from the provided URL.

Sediment cores were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator from January 14th to March 5th 2017 (IN2017_V01; Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles. The cores were collected using a multi-corer, allowing to sample the surface of the sediment (top ~ 30cm). The cores were then sliced every centimetre, wrapped up in plastic bags, and stored in the fridge. Radiocarbon (14-C) ages were measured to build an age model for future paleo-reconstructions. Sediment samples were pre-treated in the IMAS Sediment Lab (UTAS, Hobart, Australia). Samples (~ 2 g) from the multi-cores MC01, MC03 and MC06 were dried, ground and acidified with HCl for carbonate removal using sterilised beakers. Dried and ground samples were then packed into sterilised aluminium foil and sent to DirectAMS (Radiocarbon Dating Service, USA) for 14C analysis by Accelerator Mass Spectrometer (AMS). Results were corrected for isotopic fractionation with an unreported δ13C value measured on the prepared carbon by the accelerator. References L.K. Armand, P.E. O’Brien and On-board Scientific Party. 2018. Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report, Research School of Earth Sciences, Australian National University: Canberra.

Marine sediments often represent an important reservoir of carbonate minerals that will react rapidly to changing seawater chemistry as a result of ocean acidification. Ocean acidification (the reaction of CO2 with seawater) lowers the saturation state with respect to carbonate minerals and may lead to dissolution of these minerals if undersaturation occurs. There are three main carbonate minerals found in marine sediments: 1. aragonite 2. calcite (also referred to as low-magnesium calcite, containing less than 4mol% MgCO3) 3. high-magnesium calcite (greater than 4 mol% MgCO3) Due to the different structure of these minerals, they have different solubilities with high-Mg calcite the most soluble, followed by aragonite and then calcite. As seawater CO2 increases and the saturation state with respect to carbonate minerals decreases, high-Mg calcite will be the first mineral subject to undersaturation and dissolution. By measuring the carbonate mineral composition of sediments, we can determine which areas are most at risk from dissolution. This information forms an important baseline with which we can assess future climate change. The effect of ocean acidification on carbonates in marine sediments will occur around the world, but due to the lower seawater temperatures in Antarctica, solubility is much lower so the impacts will occur here first. This dataset is a compilation of carbonate mineralogy data from surface sediments collected from the East Antarctic margin. The dataset includes sample metadata, bulk carbonate content, %calcite, % aragonite and mol% MgCO3 (i.e. the magnesium content of high-Mg calcite). This dataset was compiled from new (up to 2020) and archived sediment samples that contacted sufficient carbonates (typically greater than 3% CaCO3)/

This dataset contains the data collected during the RAPPLS (Radar, Aerial Photography, Pyrometer, and Laser Scanning system) flights that were undertaken as a part of the SIPEX II (Sea Ice Physics and Ecosystems Experiment II) Antarctic marine science voyage in September-November 2012. The RAPPLS project involved designing and using a system using a helicopter with mounted sensors to record data while flying over sea ice. The RAPPLS helicopter is an Aerospaciale AS 350 BA "Squirrel" helicopter with a range of scientific equipment mounted to it. These are generally imaging instruments that are used to derive snow and ice properties, such as roughness, surface elevation and skin temperature. The following is a list of instruments used and parameters measured: - 2-8 GHz frequency modulated continuous wave radar, measuring impedance differences between snow and sea ice; - Hasselblad H3D II 50 camera, taking aerial photographs at about 13 cm resolution every 3-5 seconds - Heitronics KT 19 pyranometer, measuring skin surface temperature - Riegl LMS Q240i-60 scanning LiDAR, measuring surface elevation of sea ice above sea level All data are geo-located with a combined inertial navigation and global positioning system, OxTS RT-4003. See Australian Antarctic Division Science Technical Support Project 07006 for detailed Engineering documents. Detailed flight information for each flight is available from WORD documents for each survey. Contained in this dataset are the following files: - A MS Word log file for all flights; - A QGIS map file showing all flights; - A folder for each flight containing the following (named - Date - Fxx - Mission: - A Microsoft Word document explaining the flight intentions, issues, and outcomes (flight log); - A folder of the photos taken by the Hasselblad camera; - A folder of raw and processed INS data: - RD files, which are raw INS and can be opened RT_PostProcess software; - PNG Files showing flight track, created with RT_View software based on NCOM files resulting from RT_PostProcess; - A folder with log files for Errors, Events, LaserScanner, Pyrometer, and INS. This folder also includes Q24 file of raw laser scanner data (purpose written software to analyse the data is available with the 2008 data set); - A folder with time synchronisation log file.

Although oceanic crust covers about 60% of the Earth, relatively little is known of its geology and the processes that have created it. Macquarie Island represents a unique subaerial exposure of the seafloor, and an exceptional environment for active study and research into the ocean crust. We plan to utilise geological and geophysical techniques to help us better understand the lithological complexity and evolution of the oceanic crust. Project objectives: Our primary objective is to conduct coordinated ground- and air-based magnetic and electromagnetic surveys of the oceanic crust that comprises Macquarie Island and the surrounding seafloor for ~ 5 km from the island. We will integrate these geophysical data with the results of our recent studies of the Island and additional follow-up geological investigations. Together these data will improve our understanding of the tectonic and hydrothermal evolution of Macquarie Island ocean crust and through it, the evolution of oceanic crust in a more general sense. We believe the acquisition of these data will allow us to: (1) better resolve the complex geologic structure of the island; (2) determine the three-dimensional extent of the hydrothermal alteration of this example of oceanic crust; (3) map active fault zones across the island; and (4) correlate the geology of the Island with the offshore geology, linking it to regional data sets and the nearby active plate boundary. The dataset has two forms. The main dataset is magnetic field data recorded in the Bauer Bay to Boot Hill area of Macquarie Island, on 200 m line spacings (csv file). The subsidiary dataset are sample locations for the same area for a small set of rock samples obtained to check on magnetic character (word file). Data were collected using a GEM Systems GSM-19 Overhauser Magnetometer. The fields in this dataset are: Easting Northing Sample Rock Type Magnetic Intensity (nT) Taken from the 2008-2009 Progress Report: Progress against objectives: This project was in abeyance for the 2007-8 season due to our scientific field program being postponed as a necessity of the rabbit eradication program on Macquarie Island. A detailed study of the formation of specific magnetic lows from our regional ground magnetic survey, with the aim of determining their cause, and gaining insight into interpretation of magnetic lows in ocean crust in general. Hydrothermal alteration in ocean crust typically results in magnetic lows because it involves magnetite destruction. However, it is apparent that on Macquarie Island this is not the only cause of magnetic lows. There are 5 principal study sites: (1) Prion Lake to Brothers Point, and including the Mt Tulloch summit and slopes; (2) Waterfall Lake and surrounds; (3) Hurd Point to the coast immediately east of Mt Jefferies; (4) East Ainsworth area, east of the Caroline Cove protection zone; (5) Whisky Creek area, cutting through the eastern escarpment ~ 5 km north of Hurd Point. The 2008-9 season has involved (1) compiling of geological mapping from each site and rectification with the available topographic base and most recent satellite imagery; (2) processing of magnetic data from each of the detailed surveys; (3) extraction of field observations into a digital database that can be accessed within his GIS platform; (4) petrographic description of ~100 polished thin sections to evaluate magnetite behaviour; and (5) a brief return to Macquarie Island to attempt to infill areas of geological data/sample deficiency. In terms of the objective of correlating the geology of the island with the offshore geology, this has been in process within the USGS under the supervision of Dr Carol Finn. This part of the project is employing heli-magnetics obtained with the cooperation of AAD during resupply, using a USGS instrument The data was partly processed at Utas by Dr Michael Roach, and then transferred on for more detailed processing at the USGS.

This dataset represents the collected work arising from ASAC projects 263, 351, 497 and 716 (ASAC_263, ASAC_351, ASAC_497, ASAC_716). The data are pooled together into a single excel file, and presented by year. Descriptions/explanations of acronyms used are given at the bottom of each spreadsheet. One worksheet also details all publications arising from (and related to) the four ASAC projects. The full titles of the four ASAC projects are: ASAC 263: Metamorphic Evolution and Tectonic Setting of Granulites from Eastern Prydz Bay ASAC 351: The Role of Partial Melting in the Genesis of Mafic Migmatites and Orthogenesis within the Rauer islands ASAC 497: Structural and Chemical Processes in Granulite Metamorphism: the Rauer Group and Brattstrand Bluffs Region, Prydz Bay ASAC 716: Archaean Crustal Accretion Histories and Significance for Geological Correlations Between the Vestfold Block and Rauer Group The fields in this dataset are: Archive Collector Sample Number Location Location Code Latitude Longitude Field description Collected for Reported in Comments Type Grid reference Worker

Macquarie Island offers a rare land-based cross-section through the deep ocean floor, which covers 60% of our Earth. It formed 11 million years ago as slow spreading crust, which has had minimal study compared to more common fastspreading crust. Does the difference in spreading speed produce different crustal geometry, composition, hydrothermal fluids, and cycling of sulfur between ocean and crust? To gain insights to these and related questions, we propose to study uplifted and eroded sections through a series of fault zones, spaced along the length of Macquarie Island, which were the last magmatic, structural and hydrothermal events to occur before shifting stresses drove the seafloor up to form the Macquarie Ridge mountain chain. This dataset is a summary of samples obtained by Mr Steve Lewis for the purposes of investigating hydrothermal alteration in oceanic crust on Macquarie Island. Samples derive from the major lake, Lusitania Bay, and Caroline Cove areas. Each sample consists of rock chips up to a maximum of 1 kg. Samples were all obtained by hand with a geological hammer. The fields in this dataset are: Sample Easting Northing Date Location Transect Details