Effective management of the global ocean requires an inventory of its features and marine living and non-living resources. To help meet this need, a new global seafloor geomorphic features map (GSFM) has been created based on the analysis and interpretation of the Shuttle Radar Topography Mission (SRTM) 30 arc-second (~1 km) bathymetry grid. The new digital GSFM includes 131,190 separate polygons in 29 geomorphic feature categories. We present the first comprehensive identification, enumeration, inventory and quantitative analysis of the ocean's seafloor geomorphic features. The GSFM allows a more accurate assessment of features (proxies for benthic habitats, ecosystems and resources). GIS analysis of the GSFM illustrates that more than 50% of the area of 11 feature categories are located beyond the area of national jurisdiction, and less than 10% of 21 feature categories are protected in marine reserves globally, including shelf valleys, submarine canyons, mid-ocean spreading ridges and rift valleys.

The surface sedimentary record from six sediment cores collected from beneath the Amery Ice Shelf, East Antarctica, provides a unique view of the sedimentary and oceanographic processes in this sub-ice shelf setting. The composition and age of the surface sediments indicate spatial variations in ice shelf cavity-ocean interaction, which are consistent with patterns of ocean inflow and outflow modelled and observed beneath the ice shelf. Sediments within 100 km of the ice shelf front (site AM01b) show the greatest open ocean influence with a young surface age and the highest total diatom abundance, compared to older ages and lower diatom abundances at sites deeper in the cavity (AM03 to AM06). The variable marine influence between sites determines the nature of benthic communities, with seabed imagery indicating the existence of sessile suspension feeders in areas of strong marine inflow (site AM01b), while grazers, deposit feeders and a few suspension feeders occur at sites more distal from the shelf calving front where the food supply is lower (sites AM03 and AM04). Understanding the sedimentary and oceanographic processes within the sub-ice shelf environment allows better constraint of interpretations of down core sediment records, an improved understanding of the nature of biological communities in sub-ice shelf environments, and a baseline for determining the sensitivity of the system to any future changes in ocean dynamics.

A 2-D crustal velocity model has been derived from a 1997 364 km north-south wide-angle seismic profile that passed from Ordovician volcanic and volcaniclastic rocks (Molong Volcanic Belt of the Macquarie Arc) in the north, across the Lachlan Transverse Zone into Ordovician turbidites and Early Devonian intrusive granitoids in the south. The Lachlan Transverse Zone is a proposed west-northwest to east-southeast structural feature in the Eastern Lachlan Orogen and is considered to be a possible early lithospheric feature controlling structural evolution in eastern Australia; its true nature, however, is still contentious. The velocity model highlights significant north to south lateral variations in subsurface crustal architecture in the upper and middle crust. In particular, a higher P-wave velocity (6.24-6.32 km/s) layer identified as metamorphosed arc rocks (sensu lato) in the upper crust under the arc at 5-15 km depth is juxtaposed against Ordovician craton-derived turbidites by an inferred south-dipping fault that marks the southern boundary of the Lachlan Transverse Zone. Near-surface P-wave velocities in the Lachlan Transverse Zone are markedly less than those along other parts of the profile and some of these may be attributed to mid-Miocene volcanic centres. In the middle and lower crust there are poorly defined velocity features that we infer to be related to the Lachlan Transverse Zone. The Moho depth increases from 37 km in the north to 47 km in the south, above an underlying upper mantle with a P-wave velocity of 8.19 km/s. Comparison with velocity layers in the Proterozoic Broken Hill Block supports the inferred presence of Cambrian oceanic mafic volcanics (or an accreted mafic volcanic terrane) as substrate to this part of the Eastern Lachlan Orogen. Overall, the seismic data indicate significant differences in crustal architecture between the northern and southern parts of the profile. The crustal-scale P-wave velocity differences are attributed to the different early crustal evolution processes north and south of the Lachlan Transverse Zone.

Removing the topographic effect from satellite images is a very important step in order to obtain comparable surface reflectance in mountainous areas and to use the images for different purposes on the same spectral base. The most common method of normalising for the topographic effect is by using a Digital Surface Model (DSM) and / or a Digital Elevation Model (DEM). However, the accuracy of the correction depends on the accuracy, scale and spatial resolution of DSM data as well as the co-registration between the DSM and satellite images. A physics based BRDF and atmospheric correction model in conjunction with a 1-second SRTM (Shuttle Radar Topographic Mission) derived DSM product released by Geoscience Australia in 2010 were used to conduct the analysis reported in this paper. The results show that artefacts in the DSM data can cause significant local errors in the correction. For some areas, false shadow and over corrected surface reflectance factors have been observed. In other areas, the algorithm is unable to detect shadow or retrieve an accurate surface reflectance factor in the slopes away from the sun. The accuracy of co-registration between satellite images and DSM data is crucial for effective topographic correction. A mis-registration error of one or two pixels can lead to large error of retrieved surface reflectance factors in the gully and ridge areas (retrieved reflectance factors can change from 0.3 to 0.5 or more). Therefore, accurate registrations for both satellite images and DSM data are necessary to ensure the accuracy of the correction. Using low resolution DSM data in conjunction with high resolution satellite images can fail to correct some significant terrain effects. A DSM resolution appropriate to the scale of the resolution of satellite image is needed for the best results.

Sub-sampling is a commonly used technique to reduce the amount of time and effort for investigating biological specimens of, especially, a large quantity. However, it is not immediately clear how sub-sampling may affect the estimates of biodiversity measures such as species presence/absence, richness and abundance by using such sub-sampled data. This article quantifies the effect of sub-sampling as attenuation of the species abundance distribution. Its theoretical description is derived by accounting for the random sampling scheme of finite populations and is illustrated using sub-sampled data collected by a marine survey. It shows the theory and data are in agreement. Our method can be used to set benchmarks for sub-sampling schemes since the departure from this model estimates the unexpected bias peculiar to the sub-sampling scheme adopted. This quantification also enables the effect of sub-sampling to be incorporated into further model development for biodiversity estimates.

Marine physical and geochemical data can be valuable in predicting the potential distributions and assemblages of marine species, acting as surrogate measures of biodiversity. The results of surrogacy analysis can also be useful for identifying ecological processes that link physical environmental attributes to the distribution of seabed biota. This paper reports the results of a surrogacy study in Jervis Bay, a shallow-water, sandy marine embayment in south-eastern Australia. A wide range of high-resolution co-located physical and biological data were employed, including multibeam bathymetry and backscatter data and their derivatives, parameters that describe seabed sediment and water column physical characteristics, seabed exposure, and infauna species. The study applied three decision tree models and a robust model selection process. The results show that the model performance for three diversity indices and seven out of eight infauna species range from acceptable to good. Important surrogates for infauna diversity and species distributions within the mapped area are broad-scale habitat type, seabed exposure, sediment nutrient status, and seabed rugosity and heterogeneity. The results demonstrate that abiotic environmental parameters of a sandy embayment can be used to effectively predict infauna species distributions and biodiversity patterns. International Journal of Geographical Information Science

An igneous zircon reference material (OG1) was characterised for U-Pb isotopes by ID-TIMS, and utilised to evaluate SIMS (SHRIMP) instrumental mass fractionation (IMF) of radiogenic Pb isotopes (207Pb*/206Pb*). The TIMS 207Pb*/206Pb* reference value for OG1 was 0.29907 ± 0.00011 (95% confidence limit), 3465.4 ± 0.6 Ma. The high 207Pb* (~ 30 -g g-1), negligible common Pb, and isotopic homogeneity permitted precise (± 1-2) 207Pb*/206Pb* measurements within the analytical sessions. External reproducibility of mean 207Pb*/206Pb* ratios between sessions was demonstrated for one instrument, yielding a mean IMF of +0.87 ± 0.49. The mean 207Pb*/206Pb* ratios between instruments were dispersed beyond uncertainties, with session IMF values from +3.6 ± 1.7- to -2.4 ± 1.3, and a grand mean IMF value (twenty-six sessions) of +0.70 ± 0.52, indicating a tendency towards elevated 207Pb*/206Pb*. The specific causes of variability in IMF are unclear, but generally reflect subtle differences in analytical conditions. The common practice in SIMS of assuming that IMF for Pb+ is insignificant could result in systematic age biases and underestimated uncertainties, of critical importance for precise correlation of Precambrian events. Nevertheless, a zircon RM such as OG1 can be readily incorporated into routine dating to improve 207Pb*/206Pb* accuracy and external reproducibility.

A new approach was developed for Australia's 2011 national State of the Environment (SoE) report to integrate the assessment of biophysical and human elements of the environment. A Common Assessment and Reporting Framework (CARF) guided design and implementation, responding to jurisdictional complexity, outstanding natural diversity and ecosystem values, high levels of cultural and heritage diversity, and a paucity of national-scale data. The CARF provided a transparent response to the need for an independent, robust and evidence-based national SoE report. We conclude that this framework will be effective for subsequent national SoE assessments and other integrated national-scale assessments in data poor regions.

Lord Howe Island is a small, mid-ocean volcanic and carbonate island in the southwestern Pacific Ocean. Skeletal carbonate eolianite and beach calcarenite on the island are divisible into two formations based on lithostratigraphy. The Searles Point Formation comprises eolianite units bounded by clay-rich paleosols. Pore-filling sparite and microsparite are the dominant cements in these eolianite units, and recrystallised grains are common. Outcrops exhibit karst features such as dolines, caves and subaerially exposed relict speleothems. The Neds Beach Formation overlies the Searles Point Formation and consists of dune and beach units bounded by weakly developed fossil soil horizons. These younger deposits are characterised by grain-contact and meniscus cements, with patchy pore-filling micrite and mirosparite. The calcarenite comprises several disparate successions that contain a record of up to 7 discrete phases of deposition. A chronology is constructed based on U/Th ages of speleothems and corals, TL ages of dune and paleosols, AMS 14C and amino acid racemization (AAR) dating of land snails and AAR whole-rock dating of eolianite. These data indicate dune units and paleosols of the Searles Point Formation were emplaced during oxygen isotope stage (OIS) 7 and earlier in the Middle Pleistocene. Beach units of the Neds Beach Formation were deposited during OIS 5e while dune units were deposited during two major phases, the first coeval with or shortly after the beach units, the second later during OIS 5 (e.g. OIS 5a) when the older dune and beach units were buried. Large-scale exposures and morphostratigraphical features indicate much of the carbonate was emplaced as transverse and climbing dunes, with the sediment source located seaward of and several metres below the present shoreline. The lateral extent and thickness of the eolianite deposits contrast markedly with the relatively small modern dunes.

Widespread seagrass dieback in central Torres Strait, Australia has been anecdotally linked to the delivery of vast quantities of terrigenous sediments from New Guinea. The composition and distribution, and sedimentological and geochemical properties, of seabed and suspended sediments in north and central Torres Strait have been determined to investigate this issue. In northern Torres Strait, next to Saibai Island, seabed sediments comprise poorly sorted, muddy, mixed calcareous-siliciclastic sand. Seabed sediments in this region are dominated by aluminosilicate (terrigenous) phases. In central Torres Strait, next to Turnagain Island, seabed and suspended sediments comprise moderately sorted coarse to medium carbonate sand. Seabed sediments in this region are dominated by carbonate and magnesium (marine) phases. Mean Cu/Al ratios for seabed sediments next to Saibai Island are 0.01, and are similar to those found in New Guinea south coastal sediments by previous workers. Mean Cu/Al ratios for seabed sediments next to Turnagain Island are 0.02, indicating an enrichment of Cu in central Torres Strait. This enrichment comes from an exogenous biogenic source, principally from foraminifers and molluscs. We could not uniquely trace terrigenous sediments from New Guinea to Turnagain Island in central Torres Strait. If sediments are a factor in the widespread seagrass dieback in central Torres Strait, then our data suggest these are marine-derived sediments sourced from resuspension and advection from the immediate shelf areas and not terrigenous sediments dispersed from New Guinea rivers. This finding is consistent with outputs from recently developed regional hydrodynamic and sediment transport models.