Since the early submarine diving expeditions when our scientists and engineers observed and tested gas hydrate outcrops on the deep ocean floor, we’ve participated in most of the major gas hydrate field programmes. Gas hydrates can, in some places, contribute significant ground risk to deepwater oil and gas developments. With our technical and academic partners, we have developed gas hydrate sampling tools and complete handling systems.
We have produced analytical studies and executed field programmes in order to design structure foundations and hydrocarbon production wells in locations containing massive hydrate deposits. We also support clients, governments and energy companies, which are conducting forward-looking research to secure future clean energy supplies from gas hydrates.
Our capabilities include:
- Development of new tools and systems to ground-truth gas hydrate distribution
- Design and execution of gas hydrate investigation programmes
- Development of foundation design techniques for facilities located in regions with gas hydrates
- Prospecting for conceptually producible gas hydrate resources
- Development of predictive and quantification methods
- Project management, desk top research studies, integrated studies and geohazard assessment studies
- Installation of gas hydrate production and monitoring wells
We have identified two specific target applications for our gas hydrates investigations:
Hydrates as a Geohazard
Although drilling an exploration well through zones of gas hydrates in the shallow section is not a significant risk (it can in fact keep well stability in a better condition than wells drilled without the presence of gas hydrates), the presence of gas hydrates in the shallow sediments in a conventional hydrocarbon production well can be greatly affected by long term production through those hydrate zones. This occurs primarily where warm hydrocarbons are brought up through the structural casing over time (years of production) and warm or heat-up the hydrate zones around the surface casing and conductor. This leads to dissociation of the hydrates and production of gas and water, thereby weakening the sediments that support the well casings. Fugro has modelled this occurrence and has completed several projects to investigate long term monitoring and stability of the production wells where hydrates have been encountered.
Hydrates as a Resource
More of our gas hydrate programmes have been focussed on finding and quantifying recoverable reserves of gas from hydrate formations. This process involves a “petroleum systems” approach to prospecting the best area to perform drilling, coring, pressure coring and in situ testing of hydrate formations based on exploration seismic data. We evaluate the seismic data, assess the drilling hazards and, typically through either wireline logging or logging while drilling (LWD), identify the specific coring targets. Then using various coring and pressure coring systems, we sample the hydrates and analyse the cores to evaluate prospectivity of future production sites.
There are clear benefits from a better comprehension of gas hydrate distribution - whether for facilities design or for understanding the potential for future clean energy supply.
Conventional oil and gas development:
- Acquiring adequate information for facilities design early in project cycle
- Understanding of ground risk
- Sound facilities design for the life-of-field
- Better life-of-field performance from deepwater shallow gas fields
Future energy supply:
- Identifying and quantifying producible gas hydrate deposits
- Providing key parameters for gas hydrate production
- Assessing energy security and resources for future clean energy supply