Sinkhole geohazards

Addressing Geohazards Through Ocean Drilling

Natural geohazards, such as earthquakes, volcanic eruptions, landslides, and volcanic collapse, are of immediate societal concern. In an oceanic setting (Fig. 1), all are capable of generating tsunami that threaten coastal zones at distances of many thousands of kilometers. This power and its effects were forcefully shown by the giant earthquake (� w 9.2) and tsunami of 26 December 2004 off t...

Offshore geohazards and seabed mobility

This research stream is focussed on offshore hazards, with particular attention to the mobility of the seabed – whether through large scale geological events, or local scale sediment transport processes. This report is divided into two broad areas. We have extensive activity to report on the subject of seabed mobility, through studies around the O-Tube program (see also the separate report on t...

Grand Challenges in Geohazards and Georisks

Benthic bacterial diversity in submerged sinkhole ecosystems.

Physicochemical characterization, automated ribosomal intergenic spacer analysis (ARISA) community profiling, and 16S rRNA gene sequencing approaches were used to study bacterial communities inhabiting submerged Lake Huron sinkholes inundated with hypoxic, sulfate-rich groundwater. Photosynthetic cyanobacterial mats on the sediment surface were dominated by Phormidium autumnale, while deeper, o...

“Measurements for Assessment of Hydrate Related Geohazards”

Natural gas hydrate deposits are found in deep offshore environments. In some cases these deposits overlay conventional oil and gas reservoirs. There are concerns that the presence of hydrates can compromise the safety of exploration and production operations [Hovland and Gudmestad, 2001]. Serious problems related to the instability of wellbores drilled through hydrate formations have been docu...