The Labrador Shelf extends from the Davis Strait in the north through the Saglek Basin and down to the Hopedale Basin in the south, along the NE margin of East Canada. The majority of wells have been drilled in the Hopedale Basin. The water depths of wells drilled to-date are typically 100-200m, with only rare wells such as Hopedale E-33 and South Labrador N-79 drilled in water depths > 500m. Mud-weights used in many of the Labrador wells are low; however, there are occurrences in wells such as Pothurst P-19 of very high kicks taken, implying under-balanced drilling and highly pressured shales at depth. These highly overpressured shales (and associated reservoirs) are likely a feature of the deep-water where they will present a drilling hazard, as in similar deep-water settings worldwide.
To-date, all drilling has been therefore on the Shelf, whereas recent shooting of seismic in offshore Labrador has suggested new interest in the deep-water. Following the announcement on September 13, 2011 to shoot large-scale multi-client 2D seismic survey of offshore Newfoundland and Labrador into the deep water, understanding the shelf-to-deep water transition becomes even more crucial. In the absence of well penetrations in the deep-water, the use of analogues becomes vital.
Subsea structures on the seabed may be impacted by free-floating or scouringicebergs. A drift-based Monte Carlo iceberg contact model was developed as partof the SIRAM (Subsea Ice Risk Assessment and Mitigation) program forcalculating iceberg impact risk for subsea structures on the northeast GrandBanks offshore Newfoundland and the Makkovik Bank on the Labrador Shelf. Themotivation for developing this model was to characterize the influence ofbathymetry (i.e., seabed orientation, ridges and basins) on iceberg interactionrates with subsea structures. Results were incorporated into a GIS-basedapplication to allow iceberg contact rates to be calculated for structures witha range of plan dimensions and elevations at various locations.
To support the renewed interest in the hydrocarbon potential of the Labrador Sea, we have completed a regional seismic interpretation and integrated this with new biostratigraphic data, based on analyses of palynomorphs from wells in the Hopedale and Saglek basins. By integrating the two data-sets, we have developed a modified model for the evolution of the Labrador Margin. Our results are summarized in a tectonostratigraphic chart, which displays new and consistent age control for the major lithostratigraphic units and relates their depositional history to tectonic forces and global sea-level. Although we have identified and dated six regional unconformities in the wells, we can recognize several others on the seismic data. The older unconformities are related to the tectonics of rifting and seafloor spreading, and may delineate the onset of different stages of the rift process. In the Paleocene-Early Eocene, another significant influence was the episodic volcanism due to the passage of the proto-Iceland hot spot to the north, and to a major change in spreading direction in the Labrador Sea. During the post-seafloor spreading stage the effects of mass wasting and slumping, and of paleoenvironmental controls on the stratigraphy were more pronounced. We discuss the petroleum potential of the Hopedale Basin in terms of the structures we see on the seismic data, and highlight the Bjarni Formation, which appears to contain the most likely source and reservoir rocks.
Twenty-four oil and/or gas discoveries have been made offshore Newfoundland and Labrador. Three of the oil discoveries have been developed and a fourth is under consideration. The focus of development activity has been on the larger oil discoveries. As production from the larger discoveries matures, facilities and other infrastructure will become available for development of the remaining smaller discoveries. Development and tie-in of smaller pools and fields provides an opportunity to utilize this spare production capacity at these fields. Currently, there are several satellite tie-in and expansion projects in progress and others are under review. Development of the discovered smaller fields will play an important part in sustaining production from offshore Newfoundland and Labrador. In addition, many of the offshore basins are under explored and represent other opportunities to supply the next round of developments.
Newfoundland and Labrador, Canada's easterly province (Fig. 1) is strategically positioned on international shipping lanes, with unique access to global petroleum markets.
The exploration drilling programs offshore Newfoundland and Labrador were at the forefront of technology evolution. Deep-water drilling records were set in 1979 with the drilling of Texaco et al Blue H-28 well in 1486 metres of water, and again in 1987 with the drilling of the Northcor et al Narwhal F-99 well in 1587 metres of water. Exploration drilling was the first major oil and gas activity to have to deal with ice management. During the exploration programs, industry developed and implemented procedures to operate in ice conditions, acquired environmental and ice data and conducted ice research, which are necessary for designing and operating production facilities. Drilling programs have utilized semi-submersibles or drill ships in most areas, largely as a measure to extend programs into the periods when ice is present. These units are capable of moving off location quickly if threatened by ice.