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Repeat multibeam mapping of two slope-confined canyons on the northwest Australian margin provides new understanding of the processes that are active in shaping these environments. The Cape Range and Cloates canyons initiate on the mid to lower continental slope but are now known to be connected to the shelf via small channels and gullies. Both canyons have areas of steep walls, with evidence of slides, and large depressions on the canyon floors. These canyons were first mapped systematically with multibeam sonar in 2008 and were remapped in 2020 during a biodiversity survey that also collected high-resolution imagery and biological samples. Comparison of seabed features between these two time periods indicates active sliding, minor headwall retreat and continued excavation of deep depressions on the canyon floor. Significantly, intact blades of displaced seagrass imaged at various depths up to 4200 m throughout both canyons indicates that material sourced from the adjacent continental shelf is being transported through these canyon systems. Turbidity currents are actively modifying canyon walls and floor depressions, while also providing a sediment source that has resulted in minor accretion on the canyon floor. Sedimentation likely regulates benthic communities in these canyons, with imagery showing highest densities of sessile invertebrates in habitats protected from sedimentation (e.g. rock overhangs, cliff edges). Since steep canyon habitats are rare within these canyons, and support high benthic abundance, they likely represent biologically significant areas of the Gascoyne Marine Park. Repeat mapping provides an understanding of the dynamics of these canyons and a context for assessing and monitoring the stability of the seabed habitats within this marine reserve.

Voici le ver Bobbit, l'un des plus terrifiants prédateurs des océans.

Voici le ver Bobbit, l'un des plus terrifiants prédateurs des océans.

Floating lab drills 1.5km below sea floor to study megaquakes.

Floating lab drills 1.5km below sea floor to study megaquakes.

These resilient corals can handle conditions that would decimate other species.

These resilient corals can handle conditions that would decimate other species.

Disrupting just one process in the important relationship between microbes and bigger plants and animals that live in ocean floor sediment may have knock-on effects that could reduce the productivity of coastal ecosystems, according to international research published online yesterday in Philosophical Transactions of the Royal Society B.

Sumatra coastal cave records stunning tsunami history.

As well as being a beautiful species capable of changing its colour, shape and even gender, new research published today shows that parrotfish, commonly found on healthy coral reefs, can also play a pivotal role in providing the sands necessary to build and maintain coral reef islands.

As well as being a beautiful species capable of changing its colour, shape and even gender, new research published today shows that parrotfish, commonly found on healthy coral reefs, can also play a pivotal role in providing the sands necessary to build and maintain coral reef islands.

As well as being a beautiful species capable of changing its colour, shape and even gender, new research published today shows that parrotfish, commonly found on healthy coral reefs, can also play a pivotal role in providing the sands necessary to build and maintain coral reef islands.

FOUR-and-a-half thousand metres beneath the waves, trapped in deep-sea volcanoes and submarine canyons, the history of WA's coastline is written into the rocks.

FOUR-and-a-half thousand metres beneath the waves, trapped in deep-sea volcanoes and submarine canyons, the history of WA's coastline is written into the rocks.

Under the surface.

Under the surface.

In the second part of our report into measuring the effects of light reduction and sediment burial to determine the capacity for northwest seagrasses to withstand change, we move from the field to the lab for some surprising results.

In the second part of our report into measuring the effects of light reduction and sediment burial to determine the capacity for northwest seagrasses to withstand change, we move from the field to the lab for some surprising results.

LOOK at the world-renowned stromatolites protruding from saline seas at Hamelin Pool in Shark Bay and you could be forgiven for wondering what all the fuss is about.

LOOK at the world-renowned stromatolites protruding from saline seas at Hamelin Pool in Shark Bay and you could be forgiven for wondering what all the fuss is about.

The estimated period in which human colonization of Madagascar began has expanded recently to 5000-1000 y B.P., six times its range in 1990, prompting revised thinking about early migration sources, routes, maritime capability and environmental changes. Cited evidence of colonization age includes anthropogenic palaeoecological data 2500-2000 y B.P., megafaunal butchery marks 4200-1900 y B.P. and OSL dating to 4400 y B.P. of the Lakaton'i Anja occupation site. Using large samples of newly-excavated bone from sites in which megafaunal butchery was earlier dated >2000 y B.P. we find no butchery marks until ~1200 y B.P., with associated sedimentary and palynological data of initial human impact about the same time. Close analysis of the Lakaton'i Anja chronology suggests the site dates <1500 y B.P. Diverse evidence from bone damage, palaeoecology, genomic and linguistic history, archaeology, introduced biota and seafaring capability indicate initial human colonization of Madagascar 1350-1100 y B.P.

Scientists know that low-oxygen dead zones are growing worldwide. New research sheds light on what that will mean for estuary systems if trends continue.

A rare assemblage of sharks and rays from nearshore environments of Eocene Madagascar.

They once inhabited the seafloor and have been steadily buried: Microorganisms in the sub-surface sediments at the bottom of the Arabian Sea reveal details of fluctuations in climate and environmental conditions over the past 52,000 years.

With a death toll of more than 250,000 people, the Boxing Day tsunami of 2004 was one of the most devastating disasters of recent history.

Geological Insights from Malaysia Airlines Flight MH370 Search.

Sediment that eroded from the Himalayas and Tibetan plateau over millions of years was transported thousands of kilometers by rivers and in the Indian Ocean - and became sufficiently thick over time to generate temperatures warm enough to strengthen the sediment and increase the severity of the catastrophic 2004 Sumatra earthquake.

The deep sea is the largest environment on Earth, comprising important resources of commercial interest. It is composed of a wide variety of ecosystems, which is home to often unique organisms that are yet to be described. The deep-sea is one of the least studied environments, where research is strongly linked to technological access and advances. With the recent advances in the next-generation sequencing and bioinformatics tools, there is an enhanced understanding of microbial diversity and ecological functions in deep sea. Multidisciplinary programs are being undertaken to investigate into microbial communities in diverse marine environments. As compared to other Oceans, the deeper parts of Indian Ocean are still poorly sampled and studied for bacterial, and more so fungal diversity. The studies reporting usage of modern sequencing tools to describe uncultured microbial diversity have seen a rise in numbers in the last decade. In this review, we summarize the important findings of research works carried on bacterial and fungal diversity from the abyssal regions of the Indian Ocean and provide our views on possible future paths.

A research team led by Prof. CHANG Fengming from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS), for the first time, reported the tectonic and climatic controls on sediment transport to the Southeast Indian Ocean during the Eocene.