Hebron-Ben Nevis oil field

Hebron Oil Field, located off the coast of Newfoundland, is the fourth field to come on to production in the Jeanne d'Arc Basin. Discovered in 1981 and put online in 2017, the Hebron field is estimated to contain over 700 million barrels of producible hydrocarbons. The field is contained within a fault-bounded Mesozoic rift basin called the Jeanne d'Arc Basin.

Location

The Hebron Oil Field is located off the coast of eastern Canada in Newfoundland in the Grand Banks. It resides 350 kilometers southeast of St. John's in the Jeanne d'Arc Basin which covers roughly 8000 square kilometers. It is part of a larger oil field structure consisting of the Hibernia, White Rose, and Terra Nova oil fields. The main oil rig sits at 92 meters of water.[1]

Tectonic overview of the Jeanne d'Arc Basin

The Hebron Oil field formed as result of the early Mesozoic break up Pangea. Prior to break up the Iberian Peninsula was connected to what is now Newfoundland. At the break up a passive rift margin formed due to the creation of the Atlantic Ocean. Three major phases of Mesozoic Rifting phases occurred that affected the formation of the Hebron Oil field and Jeanne d'Arc Basin.[2]

Stratigraphy

est oil t	94

The Hebron Oil Field was deposited from the Triassic to the Late Cretaceous. Sediments continued to be deposited after the Cretaceous to create the surface structure of the field. Five major periods of deposition are what created the field and its residing structures.[2]

Triassic to Middle Jurassic

This period begins with the Mesozoic break up of Pangea and the beginning of the basin formation in the Grand Banks of Newfoundland. In the Late Triassic sediments begin to be deposited in what is now the Jeanne d'Arc Basin during a series of Mesozoic rifting events. During the lower Jurassic period, a marine environment existed in the area allowing for the deposition of interbedded carbonates and evaporates.[2]

Oxfordian - Middle Kimmeridgian

During this upper Jurassic period, the deposition of oolitc limestones, shales and carbonated cemented sandstones were deposited in the basin. The deposition of these sandstones creates ideal seismic reflectors to aid in the understanding of formations deep within the Jeanne d'Arc Basin. In the middle Kimmeridgian the deposition of the Egret source rock occurred. This source rock is composed of marls and organic rich laminated shales. After the deposition a period of uplift and erosion occurred due to the further expansion and rifting of the Atlantic Ocean that forms an unconformity at the top of the middle Kimmeridgian deposits.[2]

Middle Kimmeridgian to Valanginian

This period began with the deposition of the Jeanne d'Arc Sandstone formation which provides a minor reservoir to the Hebron field. Sandstones were deposited from the southwest of the Grand Banks. This deposition also led to the creation of the Hibernia sandstone reservoir that is also produced in the Hebron Oil field. However, it expresses poor reservoir quality.[2]

Hauterivian to Upper Barremian

This period began with minor uplift resulting in erosion after the Hibernia sandstone was deposited. After the uplift and erosion period, overlaying sandstanes, shales and limestones were deposited into the Hebron field. Subsidence and faulting continued to occur in the basin during this time.[2]

Middle Cretaceous

The main reservoir for the Hebron Oil field was deposited. The Ben Nevis Sandstone contains roughly 80% of the producible hydrocarbons for Hebron. It was formed in a marine shore face environment and is 80 to 120 meters thick. The deep part of the Ben Nevis contains good quality sands, carbonate cemented sandstones and has good reservoir properties. It has a porosity ranging from 16% to 30% and a permeability of 360 millidarcies. The shallow section contains silty, bioturbated sands with poor reservoir quality.[1]

country	Canada
region	Jeanne d'Arc Basin
offonshore	offshore
coordinates	°N, °W
operator	ExxonMobil - 36%, Chevron Corporation - 27%, Suncor Energy - 23%, Equinor - 10%, Newfoundland and Labrador Hydro - 4%
discovery	1980
start production	2017
oil production bbl/d	250000
est oil bbl

Hebron-Ben Nevis oil field

Location

Tectonic overview of the Jeanne d'Arc Basin

Tethys phase

North Atlantic phase

Labrador phase

Stratigraphy

Triassic to Middle Jurassic

Oxfordian - Middle Kimmeridgian

Middle Kimmeridgian to Valanginian

Hauterivian to Upper Barremian

Middle Cretaceous

Reservoir and trapping characteristics

Trapping mechanism

Production history and the Hebron rig

References