Page 10: of Offshore Engineer Magazine (Jul/Aug 2019)

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LEADING OFF Drilling Tech “KNOWING THE CONDITIONS

THAT LIE AHEAD IN REAL

TIME AND CONTINUOUSLY

ENABLES THE CUSTOMER

TO REDUCE DRILLING

UNCERTAINTIES.”

VERA WIBOWO,

SCHLUMBERGER

Source: Schlumberger tion while drilling. has been 160 feet along the drillstring, cessfully detecting reservoirs and salt

The tool enables the customer to make which made it possible to see 100 feet boundaries, identifying thin layers and proactive drilling decisions rather than ahead of the drill bit. avoiding drilling hazards, such as high- reacting to measurements at or behind The system uses one transmitter com- pressure formations that can lead to the bit, Wibowo says. bined with one, two or three receivers. wellbore stability issues. The tool has

She emphasizes that pre-job modeling The system applies to hole sizes ranging also been used onshore to detect a high- is crucial to understanding reservoir is- from 5 5/8 inches to 16 inches. pressure environment. sues and sensitivities to determine how With more than 100 measurements The development team – which in- far ahead the customer has the ability to available in real-time, IriSphere uses cludes a number of experts in deep direc- look. It’s also key to properly space the state-of-the-art inversion to invert for a tional resistivity – engineered the system transmitter and receivers when planning high-resolution 1D formation pro? le in in response to customer requests to be the bottom hole assembly (BHA) to ob- resistivity ahead of the bit, according to able to look ahead of the drill bit in order tain the desired sensitivity, she said. the company. to reduce drilling risks, improve ef? cien- “The further we space the transmit- In developing the tool over the course cy and place casing in speci? c locations.

ter and receivers, the further our signal of ? ve years, Schlumberger conducted “Knowing the conditions that lie propagates,” she says. more than 25 ? eld trials in Asia, Aus- ahead in real time and continuously en-

To date, she says, the largest distance tralia, Latin America, North America ables the customer to reduce drilling un- between the transmitter and receiver and Europe. These trials included suc- certainties,” Wibowo says.

10 OFFSHORE ENGINEER OEDIGITAL.COM