A time-line to the Mallik 2002 gas hydrate production research project: towards new understanding the role of natural gas hydrates in climate change and as a possible new source of world energy

Introduction

Working in Canada's far north in the winter presents unique logistical challenges. It is cold, the days are very short, and there may not be roads to where you want to go. Assembling all the equipment and personnel for a drilling and scientific program the size of Mallik 2002 requires considerable planning and coordination. This part of the web site is designed to give you a feeling for the complexity of the project; the tightly linked sequence of events, where each event is dependent on the success of the previous event, is required to ensure the success of this ambitious program. The dates given are approximate.

Mobilization of Supplies Equipment to the North (July, August, September 2001)

The cheapest way to get something as heavy as a drill rig and drilling gear to the north is by truck or by barge. Beginning in July, the drill rig was trucked from south of Edmonton to Inuvik. In July and August 25 trucks, loaded with drilling gear (casing, drill stems, drill mud, pumps, fuel, mud logging equipment, etc.) and camp and construction equipment were moved by truck from Edmonton and Calgary to Hay River in the Northwest Territories. From Hay River these materials, weighing close to 760 tons, were barged to Inuvik. From there the rig and the equipment were taken by barge to the Taglu staging site, which is as close as barges can get to the proposed drilling site on the shore of the Beaufort Sea. This intermediate way-station is necessary because the shoreline approach at the drill site is too shallow to accommodate heavily loaded barges. All the equipment and supplies, including the trucks required to move equipment to the drill site, were off-loaded and stored at the Taglu staging site, waiting for freeze-up and the building of an ice road into the Mallik drilling site. The picture shows all of this equipment stored at the Taglu staging site.

Ice Roads - Public and Private (mid-November to end of December, 2001)

In the winter, a public 150-km "ice road" is constructed and maintained by the Government of the Northwest Territories to connect the communities of Inuvik and Tuktoyaktuk. Snow is cleared from the ice to a width of 75 m and an excellent, although slippery, road surface is the result. This road carries private, commercial and recreational traffic between these two northern communities. This road passes within some 40 km of Mallik, so a privately-constructed road must be built from the government road to the drill site (see map).

Contractors have been hired by the Mallik 2002 team to construct this latter road. It was built in two stages; first, the northern portion, linking the Taglu staging site with the drill site, and then the southern portion, from Taglu to ice roads built by other petroleum exploration companies and on to the government Inuvik-Tuktoyaktuk road. Construction of the ice roads cannot begin until ice thicknesses on the Mackenzie River are sufficient to support the weight of specially equipped pick-up trucks, used to flood the ice with water to reinforce the roadway. Over a one month period, snow is plowed and trucks flood the ice to thicken it. Ultimately, a thickness of about one metre is required to support the heavy drilling equipment moving to the Mallik site. In order to begin drilling on schedule, the construction of the ice road to the drill site began by mid-November.

Camp and Drill Rig Set-up (early December)

As soon as the ice road between Taglu and the drill site was completed, all the gear (drill rig, equipment and camp accommodation modules) was moved, by truck, to the Mallik drill site and "unpacked". The camp was built, and the rig assembled in a week of feverish activity.

One Drill Rig, Three Holes, in 52 Days (mid December, 2001 to early February, 2002)

Three holes are planned for this program - two observation wells, flanking the main test well, with all three planned to go to a depth of 1200 m. Each well drilled must be equipped with blow out preventors. Permafrost (frozen ground) is over 600 m thick at this location, and the drill mud must be cooled in order to minimize thawing of the permafrost zone, and minimize dissociation of the gas hydrate lying some 200-m below the permafrost. Gas hydrates dissociate into water and methane gas when warmed or when the confining pressure is decreased.

The "spud" dates (the date drilling is to begin) are as follows: 1st observation well - December 25, 2001; 2nd observation well - January 8, 2002; main well - January 23, 2002. Until late January, the drill site is relatively deserted - the focus is on drilling. However, the first scientific observations to be made will be temperature surveys done in the two observation wells, and sampling and analysis of gases returned in the drill mud.

Coring (Early to mid-February, 2002)

For geologists, this is the most anticipated part of the program - in large part because it is not possible to predict how much core will be recovered. The plan is to retrieve at least 200 m of core, including all the gas hydrate-rich intervals. However, there are often complications encountered in the drilling process and some intervals cannot be retrieved.

The appearance of the first recovered length of drill core from the main well will launch the scientific crew into high gear. At the rig, the core will be quickly sub-sampled, with the gas content of some samples analyzed immediately and other samples preserved in liquid nitrogen or pressurized vessels for later analyses. Facilities at the drill rig are limited, so the core will be transported over the ice road to the Inuvik Research Centre (IRC). Once there, the core will be split in half lengthwise into a working half and an archival half. The core will be photographed, and described in detail for its sedimentological history. Measurements of physical properties such as porosity and permeability, thermal conductivity, magnetic susceptibility, natural gamma-ray emission and acoustic wave velocity will be made. Further sub-sampling of the core will be undertaken and samples shipped to researchers in highly-specialized laboratories around the world for further studies such as gas molecular chemistry and physics, organic and inorganic geochemistry including isoptopic studies, and microbiology. The archival half of the core will be transported south for storage by the GSC in its facility in Sidney B.C. By late February, most of the scientists at the IRC will have packed up and gone home.

Down-hole Geophysics (mid- February, 2002)

After the drilling and coring is completed, one of the observation wells and the main test well will be logged (measured) using a suite of geophysical sensors which measure electrical, magnetic, thermal and acoustic properties of the geological formations. Two seismic techniques will be used to create a three dimensional image of the gas hydrate interval. Vertical seismic profiles (VSP) will be measured in each observation well. Acoustic sources (vibrators) at the surface will transmit a signal at a variety of distances from the well-head that will be detected by sensitive receivers deployed in a string down the well. Also, a cross-well tomography experiment (XWT) will be undertaken before and during the gas hydrate production test on the well. An acoustic source in one observation well will create acoustic waves that pass through the production zone and are detected by receivers in the second observation well. This experiment will permit the observation of changes induced by the production testing in the hydrate horizons.

Production Testing (mid- to end of February, 2002)

When the drilling and coring are complete, a gas production test will be run in the main well. A ten metre interval, saturated in gas hydrates, will be isolated in the well and hot water will be piped down to that interval, to melt the ice-like gas hydrates. The water and dissociated gases will be pumped back to the surface where the gas will be separated from the water, measured, and analyzed. Research groups in the United States and Japan have been working for months modeling the anticipated response of the hydrate layer to fluids of various temperatures in an effort to maximize the gas recovery rates given the brief test interval. The goal of the production test is to determine how best to recover methane from gas hydrates and if gas hydrates can be recovered in sufficient quantities to be tapped as an economically viable energy source in the future. In common with other hydrocarbon exploration wells, the production test and results are confidential to the well partners funding the Mallik project.

Demobilization from the Site (early March)

By mid-March, temperatures in the Mackenzie Delta will start to creep up, so it is imperative that the rig and camp be packed up quickly, while the ice roads are still safe. Everything will be trucked out by the ice road to Inuvik. Some of the specialized equipment needs to be returned to Alberta at the end of the project. There is the possibility of load restrictions in the Yukon and northern British Columbia during the spring. A late demobilization could trap the drill rig and heavy equipment in Inuvik until load restrictions are lifted, resulting in expensive standby charges. Closing up the site will involve capping and sealing the wells, and removal of all evidence of the program, all according the government regulations as outlined in the permits obtained for the Mallik project.

Site visit (summer 2002)

During the summer of 2002 the drill site will be inspected to ensure that all debris is removed from the site. This visit will also provide an opportunity to download temperature data from instruments left in the 3 wells.

Scientific Results (fall 2002 - December 2004)

Over 100 researchers worldwide will be working on samples and geophysical data from the Mallik 2002. In order for them to have adequate time to fully work up their results and prepare scientific publications, there is a two year period of confidentiality, following completion of the drilling portion of the program. The results will be presented in a special session at a scientific conference in the spring of 2004 and published as a compendium of papers in a special volume. A companion CD-ROM with all the scientific data and background information will also be produced (December 2004).

While the time line ends here, the research on gas hydrates will not end here. The results from the Mallik 2002 program will provide insight into the technical challenges facing the development of natural gas hydrates as a world energy supply and on our understanding of the role of gas hydrates in global climate change. But, like any scientific investigation, the work is likely to pose more questions than it answers.