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The Milton property is located on the western edge of the well-established Viking Formation hydrocarbon fairway in SW Saskatchewan (the Kindersley-Dodsland Trend - Map 2). The Kindersley-Dodsland Viking reservoirs discovered in the 1950’s were initially exploited with vertical development drilling, downspacing and waterflood implementation. In the late nineties technological advances in horizontal drilling and multi stage frac completions introduced a secondary development strategy onto the trend whereby formerly tight, non-productive Viking facies could be developed for Viking oil reserves. The Kindersley-Dodsland Viking OOIP based on conventional development was originally estimated at 3.0 billion barrels (478 million m3). To date, these legacy Viking pools have produced 296 million barrels (47.1 million m3) for a recovery factor of about 10%. From 2003 to present, the development of the unconventional component of the Viking play resulted in an increase to recoverable reserves of approximately 82 million barrels (13 million m3) or 38% over the fairway. The majority of this increase can be attributed to horizontal drilling and multi-stage frac completions in shaly, tighter, Viking rock.


The Viking Formation in the Milton area consists of a 9.0 to 12.0 metre upper, silty-sandstone member overlying a 2.0 to 4.0 metre thick basal conglomerate lag. Based on core, the tighter upper unit ranges from 14 to 20% porosity and 5 to 60 Md permeability. The lower conglomerate unit averages about 24% porosity with permeabilties reaching 1500 Md.  Completion attempts to date have focussed on the conglomerate lag and in spite of very favourable reservoir properties the zone appears prone to premature high water cut (Fig. 2).

Figure 2

The Milton property is offset by significant Viking horizontal development to the south by Novus Energy Inc. (Yangchang Petroleum International Limited) in the Marengo Area, to the east by Whitecap Resources Inc. in the Whiteside Viking pool and to the northwest by Penn West Petroleum Ltd. in the Esther Area on the Alberta side. These operators have had success in accessing the in place oil reserves contained in the unconventional, silty-sand, Viking rocks.

The target Viking horizon at Milton ranges in depth from 725 metres to 750 metres. The average gravity of the oil is 32 API. Most offsetting operators have completed the Viking using monobore completion techniques.

Initial Petro One vertical development targeted the Viking Basal Conglomerate lag
recognized in the Area. Vertical wells targeted the conglomerate in areas where it was occupying a north-south trending Viking low (MAP 3 and 4). The recognition of structurally lower conglomerate reservoirs led to the development of oil prone Viking on company lands as opposed to gas prone Viking strata located to the west on structurally higher Viking. The initial Petro One Viking horizontal development well (6-22-30-27W3M) attempted to avoid premature water with a well path outside the recognized Viking lag fairway. While encountering oil saturated tight Viking, the well has yet to perform up to type curve. It is possible that a properly placed well path in the upper Viking zone within the Viking lag fairway would access tight Viking oil reserves while having the added advantage of accessing the pressure support from the lag. Petro One recognized this possibility as it had surveyed 6 additional horizontal development wells shortly before the Gold strike merger.

Conglomerate Lag and
Viking Regional Trough

Map 4
Viking Structural Trough