Fugro provides the highest quality in geohazard assessments. Our expertise includes specialised capabilities in shallow section data analysis as well as geological core logging, testing and analysis to determine the risks associated with identified geohazards and provide total integration of the multidisciplinary datasets. Geohazard services include:
We employ a suite of geoscience, logging, testing, analysis and engineering skills to determine the risks associated with identified geohazards. We also provide site-specific probabilistic and post-event analysis of regional geological activity, with probabilistic analysis undertaken where the potential for geological activity has been escalated.
Core Logging, Sedimentology and Micropalaeontology
With experts worldwide who specialise in logging and analysing cores obtained during a regional or site investigation, we define the stratigraphy and history of the geological processes active in the region. A laboratory testing programme of samples collected during investigations can be tailored specifically to quantifying the risks associated with the geohazards; this will incorporate our expertise in geoscience, logging, sedimentology and micropaleontology.
The geohazard impact zones defined in a geohazard assessment process can either be avoided or, where this is not possible, will inform the engineering design process to consider mitigating measures that reduce the impact to an acceptable level. Based on the sensitivities and parameters of the soil units, the zones of impact of the active geohazards can be defined as well as the impact on the field infrastructure. We provide advice on the design of remedial actions required to rectify immediate issues and mitigate against future potential risks.
Selection of the optimal location of a subsea structure or route for a submarine cable or pipeline is constrained by the risks of exposure to quantified geohazards but must also consider installation constraints. We perform a weighted multivariate analysis with a least-cost routing algorithm to minimise the aggregated routing cost. A probabilistic approach can be adopted to assess relative importance and sensitivity of individual constraints and guide the decision process. In addition, installation constraints such as maximal route curvature can be added in the optimisation process, delivering a realisable route abstracted to a series of curved and straight segments that is fit for installation.
Geohazards can present significant risks for deepwater projects and can be present throughout the operational life of a field development. The key to addressing these risks is early identification of the geohazards and consideration of their possible impacts; as more data become available during the planning and design process these are continually refined.
Our services are divided into three main categories:
- Geohazard Evaluation – Identification and assessment of:
- Slope stability (and mass wasting processes)
- Karst features
- Ground motion
- Volcanic activity
- Sediment mobility (scour)
- Submarine mass transport
- Debris flow, mud flow, turbidity run out and impact assessment
- Gas hydrate (disassociation)
- Hydrology and flooding
- Core Logging, Sedimentology and Micropalaeontology – As part of a risk assessment detailed core logging can help to define the stratigraphy and history of geological processes and the results used to define the sensitivity and engineering parameters of the soil units. The soils can be examined by our sedimentologists to understand the stratigraphy, the soil composition and provenance as well as the mode of transport and depositional processes. Micropalaeontology can be used to understand the environment and the history of the geology and palaeo-environments over time and even date the sediments to give a more detailed depositional history. This provides a detailed insight and understanding of the nature and formation of the soils and geological sequence.
- Engineering – Leveraging our significant expertise:
- Qualitative and Quantitative (including probabilistic) Geohazard Risk Assessments – Defining the engineering parameters of the soil units (through a programme of core logging, testing and interpretation). Zones of impact of the active geohazard are then defined and the impact on the field infrastructure is assessed. The risks to the field development are quantified based on the probability and magnitude of geohazard activation and the impact upon field infrastructure. Cost modelling enables assessment of the cost of various different risk mitigation scenarios. Based on these results the location and design of the field infrastructure is optimised.
- Geohazard Risk Assessment – We undertake regional and site assessments which describe the seabed and sub-seabed conditions for any offshore development or an exploration or appraisal well. We also perform interpretation and analysis of acoustic and seismic datasets, and identify and assess geohazards that affect a development, drilling operations and rig integrity. Whether data have been collected in a purpose designed site survey, or existing exploration 3D seismic is used, we provide the highest quality geohazard assessment in any water depth.
- Risk Mitigation Studies and Remedial Works – The first step is a desk study where we prepare a data acquisition specification to define the scope and specification for post-event survey. We then perform post-event laboratory testing and interpretation of the available data; using the interpreted engineering parameters a site-specific analysis of the geological processes resulting from the regional activity is performed. Next we identify and assess the likely impacts of the event on the facilities and quantify the risks and finally we provide advice on remedial actions required to rectify immediate issues and mitigate against future potential risks.