<strong>AAPG</strong> EXPLORER ‘Crackle Frac’ some chalk Rockies’ Niobrara Play Expanding By LOUISE S. DURHAM, EXPLORER Correspondent Gas was hot. Now it’s not. Whiplash, anyone? Owing to the past couple <strong>of</strong> years when highly productive shale gas plays have sprouted like weeds in myriad locales in the United States, essentially in sync with cratering demand, oil is king – for now. Given the current oil-gas price differential hovering around 15:1 or more, it comes as no surprise that a number <strong>of</strong> E&P folks, principally independents, are moving at near warp speed to stake their claim in oil plays, particularly oil shales and those rich in NGLs. Meanwhile, some <strong>of</strong> the Big Guys, e.g., ExxonMobil, BP, Total and others, have bought into the shale gas plays via joint ventures and acquisitions, with the long term in mind. In addition to these deals, some <strong>of</strong> the independents’ positions in shale gas have begun to pay <strong>of</strong>f, so these trailblazers in commercial shale gas have cash on hand to dig into something currently more lucrative. This is good news for the Rocky Mountain region, which has been pummeled by low prices and sinking demand for natural gas. There’s oil in them thar’ hills. For example, operators have been working diligently the past couple <strong>of</strong> years to successfully wrest oil from the high pr<strong>of</strong>ile Upper Devonian-Lower Mississippian Bakken shale play in Montana and North Dakota. According to a U.S. Geological Survey assessment, the Bakken harbors an estimated 3.65 billion barrels <strong>of</strong> undiscovered, technically recoverable oil, 1.85 Tcf <strong>of</strong> associated/dissolved natural gas and 148 mbo <strong>of</strong> natural gas liquids. Early attempts to produce the Bakken economically were an exercise in frustration for the operators, and it was usually looked on as a bailout zone. <strong>AAPG</strong> member and 2006 <strong>Explorer</strong> <strong>of</strong> the Year Dick Findley is credited with cracking the 10 JUNE <strong>2010</strong> WWW.<strong>AAPG</strong>.ORG Photos courtesy <strong>of</strong> Randy Ray Niobrara Formation-Fort Hayes member: Vertical fractures in thick bedded limestones, east dipping outcrop, north <strong>of</strong> Boulder, Colo., along the Colorado Front Range. code for the Bakken in 1995, ultimately leading to development <strong>of</strong> the giant Elm Coulee Field in the Bakken in eastern Montana. Today, the prolific Bakken has some respectable competition. For example, the underlying Three Forks formation – which now is considered to be separate from the Bakken – reportedly may contain as much recoverable oil as the Bakken, which has more oil overall. The North Dakota Department <strong>of</strong> Mineral Resources has released more conservative numbers than the USGS estimate. It reportedly credits the Bakken with a mere two billion barrels recoverable, but also forecasts two billion as well for the Three Forks, which contains about one-eighth the total oil <strong>of</strong> the Bakken. Niobrara Potential Higher up the geologic section in the Cretaceous, there’s apparently a mother lode just waiting to be seriously exploited. “When you ask what’s happening in the Rockies, the answer is oil shale plays,” said Denver-based <strong>AAPG</strong> member Randy Ray, “and the hot topic is the Niobrara. “The Niobrara is part <strong>of</strong> the Cretaceous seaway that covered the whole middle <strong>of</strong> the U.S,” Ray noted. “We’ve had cycle after cycle <strong>of</strong> exploration for Niobrara fractures, mainly oil but some gas where it’s buried deeper. See Rockies, page 24
<strong>AAPG</strong> EXPLORER WWW.<strong>AAPG</strong>.ORG JUNE <strong>2010</strong> 11