Marco Patacci

A consistent global approach for morphometric characterisation of subaqueous landslides

Abstract Landslides are common in aquatic settings worldwide, from lakes and coastal environments to the deep sea. Fast-moving, large-volume landslides can potentially trigger destructive tsunamis. Landslides damage and disrupt global communication links and other critical marine infrastructure. Landslide deposits act as foci for localized, but important, deep-seafloor biological communities. Under burial, landslide deposits play an important role in a successful petroleum system. While the broad importance of understanding subaqueous landslide processes is evident, a number of important scientific questions have yet to receive the needed attention. Collecting quantitative data is a critical step to addressing questions surrounding subaqueous landslides. Quantitative metrics of subaqueous landslides are routinely recorded, but which ones, and how they are defined, depends on the end-user focus. Differences in focus can inhibit communication of knowledge between communities, and complicate comparative analysis. This study outlines an approach specifically for consistent measurement of subaqueous landslide morphometrics to be used in the design of a broader, global open-source, peer-curated database. Examples from different settings illustrate how the approach can be applied, as well as the difficulties encountered when analysing different landslides and data types. Standardizing data collection for subaqueous landslides should result in more accurate geohazard predictions and resource estimation.

Metadata Approaches and Their Effects on Deep-Marine System Analysis, Analogue Selection and Reservoir Characterisation

A metadata approach is described that enhances the ability to characterise and model siliciclastic deep-marine hydrocarbon reservoirs. This is achieved through a relational database approach - the Deep-Marine Architectural Knowledge Store (DMAKS) – which entails a consistent method of data entry, ensuring data from ancient, modern and sub-surface investigations are stored to a common standard. The DMAKS stores information relating to the depositional systems’ setting and environmental controls, the architectural geometry and facies characteristics, along with hierarchical and spatial relationships. This deep-marine data repository thus enables quantitative meta-data analysis. The expansive range of data and parameters contained within the database improves the quality of predictive models, while the ability to produce statistical outputs enables deep-marine analogues to be more objectively selected. An initial investigation into a single case-study – the Golo system – helps to demonstrate the DMAKS research capabilities. Here, an original lobe-type architectural model is tested against a larger data-pool. The DMAKS quantitatively verifies the existence of distinct parent lobe-types (small, single-story versus larger, composite lobes associated with leveed-channels) through the analysis of geometrical, hierarchical and spatial relationships. It also provides new insights, as the hierarchical status of a lobe is seen to influence its resultant geometry.