The Arctic region holds vast natural resources. In its Circum-Arctic Resource Appraisal (CARA), the U.S. Geological Survey estimated that 90 billion barrels of oil, 1,669 trillion cubic feet of natural gas, and 44 billion barrels of recoverable natural gas liquids may exist in 33 Arctic provinces, of which approximately 84% is offshore.
While the federal government recently announced plans to lease three Alaskan oil reserves by 2022, it is far from certain that drilling will ever happen at these sites. Oil prices remain low, and no one knows whether prices will increase enough to make exploration economically worthwhile. Furthermore, arctic oil exploration is extremely risky. Sea ice is present for more than half the year, hindering transport of equipment, supplies, and personnel to and from the site. Offshore drilling is also more complex and expensive than land operations, and especially so for drilling in extremely deep water, which is where most of the arctic oil is likely to be. On land, warming conditions create unstable conditions. (Read Unconventional Oil Exploration, Part 2: The Arctic Frontier.)
The major risk factor for oil and gas exploration and production (E&P) in the arctic, and anywhere else, is failing to find the most productive deposits. Oil companies typically employ petroleum geologists to determine where the most productive drilling spots will be, but even a small mistake in calculations can mean millions in lost revenue.
Geologists need efficient, streamlined technologies to pinpoint the most productive strata and avoid drilling in the wrong spot. The key to identifying the best drilling targets is to conduct sample analyses of drill cuttings, outcrops, piston-core sediment, and oil and gas cores. These sample types provide valuable information about the mineral composition of the deposit and whether or not it has properties favorable to oil and gas production. The data produced by this sample chemical analysis serves five critical functions in E&P:
Inferring Mineralogy: Bulk chemical analysis is used to infer the mineralogy of the rock.
Inferring Lithology (Mud Logging): The elemental composition and ratios of light elements found in the analysis is used to determine whether you’re drilling through limestone, dolomite, sandstone, siltstone, or shale. (Read The Key to Successful Mud Logging, Part 1)
Chemostratigraphy: The study of the variation of chemistry within sedimentary sequences. Key chemostratigraphic markers can be used to steer the well bore in real time or confirm the well bore path.
Reservoir Characterization: Various physical characteristics of the reservoir (such as porosity, permeability, and fracture population can be inferred from chemical composition.
Oil and Gas Productivity: A determination of whether or not the strata will produce oil and gas
Quickly gaining an understanding of these qualities is critical to making decisions about whether to stop or continue drilling, where to focus on the grid, and when to take a proper sample for laboratory analysis. Portable x-ray fluorescence (XRF) analyzers are a valuable way to accomplish successful oil and gas E&P. Portable XRF analyzers provide rapid, real-time, on-site chemical analysis so that immediate decisions can be made to optimize production or operations. XRF instruments are not used to directly analyze hydrocarbon fluids, but they can analyze major and trace elements of host rocks, which can help determine the hydrocarbon potential of the strata.