In four short years, the Clearwater cold flow heavy oil play at Marten Hills and Nipisi has gone from interesting land sales to producing over 14,000 bopd. Over 6 mmbo have been produced to mid-July 2019. The main players are Spur and Deltastream, with Highwood, Cenovus and CNRL also active (map). A timeline shows the interplay of drilling activity and land sales, while a graph shows that oil rates went from almost zero in late 2016 to over 14,000 bopd in mid-2019. The potential size ofthe prize is substantial. For example, in the six townships at the heart of Spur’s and Deltastream’s development at Marten Hills (T73–75, R24–26W4), Canadian Discovery conservatively calculates a resource of 4.96 billion barrels ofoil-in-place assuming average reservoir parameters of 12m net pay, 22% porosityand 40% water saturation.
The play is expanding just north of the main fairway (Spur and Turnstone), and also much further afield to the southeast at Canal (Deltastream), at Jarvie, which is outside the map area (Spur and others), and to the northwest at Gift (Summerland), Golden (Spur and Baytex) and Cadotte (Spur). The play shows no sign of abating as land continues to be posted along trend.
The key to unlocking the play is the volume of reservoir that operators have been able to access usingmulti-laterals (currently four to eight) produced through one production string without having to use costly hydraulic fracturing technologies or secondary thermal technologies (SAGD, CSS, etc.). With the multiple legs, the relatively high permeability (1–900 mD) Clearwater reservoir is capable of producing economic volumes of 14–24° API gravity oil on primary production. Wells cost from $1.24MM to $1.7MM for an array of multi-laterals that will produce from one production string (Highwood, 2019).
Through the years, multiple wells penetrated the Clearwater on their way to deeper targets. Though mud logs indicated that hydrocarbons were present, a combination of low oil prices and high gas prices caused the pay to be overlooked. In addition, the Clearwater reservoirs are feldspathic litharenites with a high kaolinite content—a lithology that dampens or inhibits open hole wireline log responses (Innes, 2018). In other words, the pay is hard to see!
The Clearwater play has kicked off similar developments. Spur’s project at Jarvie and West Lake’s project at Swimming are using unstimulated open hole multi-laterals to produce stratigraphically equivalent sands. No doubt, other developments will follow!
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