Tech Transfer Track

Clamping Down on Oilfield Theft

Recent years have seen the resurgence of oilfield theft. Although field activity is not at a peak, excesses of used equipment of the late 1990s are gone. On the service end, contractors are making used equipment last longer. Net effect is that demand for "used” and often misappropriated equipment is high.

Thieves generally fall into three categories—petty thiefs, random thiefs or organized thiefs. Petty thiefs steal small items for a variety of reasons. Random thieves seize opportunities to steal equipment for end users in return for cash. Organized thieves have a network of vendors that can move equipment around the country quickly. Fences are usually used equipment dealers.

The most important solution is to communicate well and quickly with each other. Establish a network for reporting theft. Contact local law enforcement and industry theft protection services like Tool Branding Service and know reporting procedures and requirements. Know your suppliers and purchase only from reputable dealers. Inventory assets and keep track of them. Establish a unique coding system that allows positive identification. Cooperation among contractors and producers is essential.

Excerpted from "Plague of the Industry—Oilfield Theft"by Brad Roberts, Tool Branding Service (phone 505-393-1452), Hobbs, New Mexico in Well Servicing, September/October 2002, p. 44-45.

Independent Validation of Reservoir Geometry Using Surface Pressure Measurement

A wave mechanics approach to pressure transient analysis, based on a radial element capillary wave model, can be employed to produce 2-D images of reservoir boundaries. This approach can be used to independently corroborate seismically- or geologically-derived images of reservoir shape at relatively low cost using surface pressure measurements. A "blind" test for a gas well resulted in a reservoir image closely matching seismic interpretation.

Wave mechanics modeling provides a more complex model of the reservoir than the diffusivity model of conventional pressure transient analysis. Imagining the reservoir as a complex network of capillary stream tubes allows one to process discontinuities in pressure data more directly, rather than smoothing them to fit a simpler model. In a bounded reservoir, slope changes can be identified for each boundary with each related by distance from the well and shape. In the referenced gas well example, reservoir volume and shape were consistent with operator's geological/seismic mapping and with reserve calculations by an independent
engineer.

The accuracy of porosity, fluid mobility, pay count, water saturation, compressibility and the downhole pressure conversion all influence the deviation of results from true reservoir shape. Map accuracy is highly dependent on accuracy of the bottomhole pressure data. Pay count and petrophysical parameters must be "on the mark" for the approach to work. The key to surface pressure measurement is transducer quality and the technology level of the algorithm used to convert surface data to downhole conditions. Technology advances make surface measurement increasingly possible.

Excerpted from "Surface Measurement Aids Imaging,"by Fred Goldsberry et.al. in Hart's E&P, November 2002, p. 58-60.

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Produced Water Databases

A Produced Water Database has been provisionally released online by George Breit and Chris Skinner of the United States Geological Survey. This database is a revision of a database originally compiled at DOE's Fossil Energy Research Center in Bartlesville, OK. USGS modified the database by removing redundancies, verifying internal consistency, and adding information to the fields that describe the location, geologic setting, sample type and major ion chemical composition. Access the USGS database at http://energy.cr.usgs.gov/prov/prodwat/index.htm/.

Producers should also watch for a "New Mexico Water And Information Data System: A Produced Water Quality and Infrastructure GIS Database" being developed by the Petroleum Recovery Research Center (PRRC) at New Mexico Tech within its DOE PUMP II project (http://www.fossil.energy.gov/techline/tl_pump2_sel.shtml). PRRC will design a website that includes comprehensive oil field and ground water information databases. Included in this website will be risk assessment tools to identify the seriousness of a produced water spill and offer suggested corrosion mitigation strategies. This consolidated information system will save countless administrative hours required to research the nature and components of produced water in the region. It will also assist oilfield operators in anticipating and planning corrosion management strategies.

Contact Martha Cather, martha@prrc.nmt.edu, for more information about status of database development.

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Table of Contents	Vol. 8, No.4 4th Quarter 2002