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The northern Gulf of Mexico is home to several species of corals that provide a wide range of ecosystem services to other organisms. Oil and gas infrastructure, such as platforms and pipelines, form an extensive network throughout the northern Gulf of Mexico. Detrimental impacts associated with oil and gas exploration and extraction have been recorded in this area at depths where corals are found. Due to these ecosystems' vulnerability to long‐term impacts, it is necessary to determine areas of interest that would benefit from further exploration and informed spatial planning. This study aimed to identify potential areas of interest for coral studies in the northern Gulf of Mexico. Ensemble species distribution models for 13 species of corals including scleractinians, black corals, and octocorals were produced based on seafloor characteristics and combined to identify areas with relatively higher coral diversity potential than others. The ensemble modelling approach produced robust outputs, as evaluated by the area under the curve, Cohen's kappa coefficient, sensitivity, specificity and the proportion of correct predictions. The proximity of suitable habitat to active and proposed oil and gas infrastructure was evaluated; this spatial analysis showed that oil and gas infrastructures potentially impact 23.5% of all predicted suitable coral habitat in the study area and contribute to benthic habitat fragmentation. Twelve areas of interest greater than 100 km2 and located outside a 4‐km zone of potential influence from oil and gas infrastructure were delineated and deemed of interest for further exploration and spatial planning, and hypothetical prioritization scenarios for spatial planning are presented. The maps produced can inform discussions among stakeholders to reach the best spatial planning outcomes while considering other ecological, social, economic and governance factors. [ABSTRACT FROM AUTHOR]

The loss of marine biodiversity is a major global issue that needs to be prioritised. In Australia, a considerable proportion (48%) of its Exclusive Economic Zone is dedicated to marine protected areas. To effectively manage this network of marine protected areas Australia has recently introduced a Management Effectiveness system. This system is designed to identify, monitor, and manage natural values and the various activities and pressures affecting the Australian Marine Parks (AMPs). Key to this approach is the identification and accurate mapping of the location of these values and pressures acting on the seabed. The AusSeabed program is a national initiative in Australia aimed at improving access to bathymetric data and coordinating efforts to collect such data in Australian waters. This manuscript proposes a novel systematic processing method to create detailed and scalable geomorphometric maps from AusSeabed's bathymetric data holdings, intended as a standard operating procedure for initial bathymetric data interpretation in the AMPs. Utilising this workflow, we produce seafloor geomorphometry maps across 37 AMPs within which sufficient bathymetric data has been collected. These maps can be used 1) for predictive mapping of biological assemblages; 2) in field sampling design for the collection of 'ground truthing' data (e.g. underwater imagery and sediment samples) to validate habitat maps from bathymetric datasets; and 3) as input datasets for subsequent geomorphological mapping with a deeper understanding of seafloor processes. This research highlights the importance of robust geomorphometry classification standards to ensure consistency in mapping Australia's marine estate in preparation for the Decade of Oceans plans. The Seamap Australia program provides a stepwise approach to advancing Australia's national collection of bathymetric data into derived products that can enable habitat mapping of Australian waters, providing a foundational tool for the adaptive management of AMPs. [ABSTRACT FROM AUTHOR]

The loss of marine biodiversity is a major global issue that needs to be prioritised. In Australia, a considerable proportion (48%) of its Exclusive Economic Zone is dedicated to marine protected areas. To effectively manage this network of marine protected areas Australia has recently introduced a Management Effectiveness system. This system is designed to identify, monitor, and manage natural values and the various activities and pressures affecting the Australian Marine Parks (AMPs). Key to this approach is the identification and accurate mapping of the location of these values and pressures acting on the seabed. The AusSeabed program is a national initiative in Australia aimed at improving access to bathymetric data and coordinating efforts to collect such data in Australian waters. This manuscript proposes a novel systematic processing method to create detailed and scalable geomorphometric maps from AusSeabed’s bathymetric data holdings, intended as a standard operating procedure for initial bathymetric data interpretation in the AMPs. Utilising this workflow, we produce seafloor geomorphometry maps across 37 AMPs within which sufficient bathymetric data has been collected. These maps can be used 1) for predictive mapping of biological assemblages; 2) in field sampling design for the collection of ‘ground truthing’ data (e.g. underwater imagery and sediment samples) to validate habitat maps from bathymetric datasets; and 3) as input datasets for subsequent geomorphological mapping with a deeper understanding of seafloor processes. This research highlights the importance of robust geomorphometry classification standards to ensure consistency in mapping Australia’s marine estate in preparation for the Decade of Oceans plans. The Seamap Australia program provides a stepwise approach to advancing Australia’s national collection of bathymetric data into derived products that can enable habitat mapping of Australian waters, providing a foundational tool for the adaptive management of AMPs.

The Caroline Ridge (CR) subduction underneath the Philippine Sea Plate brings complex morphotectonic characteristics to the Yap Subduction Zone (YSZ) compared to other normal intra-oceanic subduction systems. However, due to the relative paucity of precise geomorphological information, the detailed morphotectonic settings of the YSZ remain unclear. Therefore, we combine the latest-released bathymetry, marine geomorphometry techniques, and geophysical information to investigate the geomorphological characteristics of landforms in the YSZ and their inter-relationship with the CR subduction. The Parece Vela Basin displays NE-SW oriented fractures which are believed to be influenced by the subduction of CR in the ESE-WNW direction. The north part of the Yap arc exhibits higher Bouguer anomalies, implying the absence of the overlying normal volcanic arc crust. The arc-ward trench shows abnormal higher slope values and reveals two significant slope breaks. The Yap Trench axis reveals varying water depths with an extraordinarily deep point at around 9000 m. The sea-ward trench slope displays higher slope values than normal and shows the presence of grabens, horsts, and normal faults which indicate the bending of the CR before subduction. The CR subduction is observed to be critical in the formation of significant geomorphological characteristics in the YSZ. [ABSTRACT FROM AUTHOR]

The Caroline Ridge (CR) subduction underneath the Philippine Sea Plate brings complex morphotectonic characteristics to the Yap Subduction Zone (YSZ) compared to other normal intra-oceanic subduction systems. However, due to the relative paucity of precise geomorphological information, the detailed morphotectonic settings of the YSZ remain unclear. Therefore, we combine the latest-released bathymetry, marine geomorphometry techniques, and geophysical information to investigate the geomorphological characteristics of landforms in the YSZ and their inter-relationship with the CR subduction. The Parece Vela Basin displays NE-SW oriented fractures which are believed to be influenced by the subduction of CR in the ESE-WNW direction. The north part of the Yap arc exhibits higher Bouguer anomalies, implying the absence of the overlying normal volcanic arc crust. The arc-ward trench shows abnormal higher slope values and reveals two significant slope breaks. The Yap Trench axis reveals varying water depths with an extraordinarily deep point at around 9000 m. The sea-ward trench slope displays higher slope values than normal and shows the presence of grabens, horsts, and normal faults which indicate the bending of the CR before subduction. The CR subduction is observed to be critical in the formation of significant geomorphological characteristics in the YSZ.

Geomorphological research based on geomorphological mapping seeks to identify the origins and age of forms as well as to describe the process that created or transformed a particular form. One of the most important aspects of this study is the morphometry and morphology of the landscape. This also applies to the submarine areas, and issues related to marine geomorphometry. Bathymetric data used in this study were obtained from the measurements of the Norwegian Hydrographic Service and measurements conducted by the authors. Its main goal was: to determine the bathymetry of the Recherchefjorden (Bellsund, Svalbard), establish morphometric parameters for the analysis of the morphology of the bottom. The boundaries of zones, related to the specific character of bottom geomorphology linked with geological structure, tectonics and, in particular, the impact of glacial system, was delineated. The sets of landforms (areas) were distinguished based on the morphometric analysis resulting from the determined parameters: slopes, its aspects, curvatures and Bathymetric Position Index. Basically, this areas are concentrated in two zones: the main Recherchefjorden and its surroundings. The delimitation also takes into account the origins and location of theme in relation to the glacial systems. On this basis, moraine areas were distinguished. They are linked with the Holocene advances of two glaciers, Renardbeen and Recherchebreen, mainly during the Little Ice Age. They constitute boundary zones between areas with different morphometric parameters: outer fjord and inner fjord. Moreover, taking into account geology and terrestrial geomorphology it was possible to describe paraglacial processes in this area.

Geomorphological research based on geomorphological mapping seeks to identify the origins and age of forms as well as to describe the process that created or transformed a particular form. One of the most important aspects of this study is the morphometry and morphology of the landscape. This also applies to the submarine areas, and issues related to marine geomorphometry. Bathymetric data used in this study were obtained from the measurements of the Norwegian Hydrographic Service and measurements conducted by the authors. Its main goal was: to determine the bathymetry of the Recherchefjorden (Bellsund, Svalbard), establish morphometric parameters for the analysis of the morphology of the bottom. The boundaries of zones, related to the specific character of bottom geomorphology linked with geological structure, tectonics and, in particular, the impact of glacial system, was delineated. The sets of landforms (areas) were distinguished based on the morphometric analysis resulting from the determined parameters: slopes, its aspects, curvatures and Bathymetric Position Index. Basically, this areas are concentrated in two zones: the main Recherchefjorden and its surroundings. The delimitation also takes into account the origins and location of theme in relation to the glacial systems. On this basis, moraine areas were distinguished. They are linked with the Holocene advances of two glaciers, Renardbeen and Recherchebreen, mainly during the Little Ice Age. They constitute boundary zones between areas with different morphometric parameters: outer fjord and inner fjord. Moreover, taking into account geology and terrestrial geomorphology it was possible to describe paraglacial processes in this area. [ABSTRACT FROM AUTHOR]

Data acquisition artefacts are commonly found in multibeam bathymetric data, but their effects on mapping methodologies using geographic information system techniques have not been widely explored. Artefacts have been extensively studied in terrestrial settings, but their study in a marine context has currently been limited to engineering and surveying technology development in order to reduce their amplitude during data collection and postprocessing. Knowledge on how they propagate to further analyses like environmental characterization or terrain analysis is scant. The goal of this paper is to describe the contribution of different types of artefacts to marine terrain attributes at multiple scales. Using multibeam bathymetric data from German Bank, off Nova Scotia (Canada), digital bathymetric models (DBMs) were computed at five different spatial resolutions. Ten different amplitudes of heave, pitch, roll, and time artefacts were artificially introduced to generate altered DBMs. Then, six terrain attributes were derived from each of the reference and altered DBMs. Relationships between the amplitude of artefacts and the statistical and spatial distributions of: 1) altered bathymetry and terrain attributes surfaces and 2) errors caused by the artefacts were modeled. Spatial similarity between altered and reference surfaces was also assessed. Results indicate that most artefacts impact spatial similarity and that pitch and roll significantly impact the statistical distribution of DBMs and terrain attributes while time and heave artefacts have a more subtle impact. Results also confirm the relationship between spatial data quality and spatial scale, as finer-scale data were impacted by artefacts to a greater degree than broader-scale data. [ABSTRACT FROM PUBLISHER]