Raw analog signals from the receiver coils are digitized immediately within the tool. Advanced mathematical algorithms process these signals in real-time, stripping out environmental noise and borehole skin effects before sending the data to the surface. Key Benefits of the NGI Tool
: Uses multiple pads with microelectrode "buttons" to capture high-density resistivity measurements, creating a photorealistic map of the borehole wall.
A horizontal well targeting a 10-foot porous dolomite zone. Surrounding the target are dense, non-porous limestone and anhydrite.
Mapping structural geology and tracking continuous reservoir sand bodies across an entire field.
: The Ultrasonic Borehole Imager (UBI) uses sound waves to "see" the borehole wall, providing insights into fractures and stress orientation regardless of fluid type. schlumberger ngi tool
The NGI tool is a wireline logging instrument designed to measure the electrical resistivity of geological formations. Resistivity is a critical parameter because hydrocarbons (oil and gas) are highly resistive, while the saltwater found in many formations is highly conductive.
The NGI tool uses three scintillation detectors. BGO crystals are chosen for their high stopping power (efficiency) at high gamma ray energies.
: Newer services like the Quanta Geo Photorealistic Imager offer even higher borehole coverage (up to 98% in 8-inch holes) and allow for faster logging speeds up to 3,600 ft/h.
Typically featuring four or more pads, the tool ensures high circumferential coverage of the borehole. Raw analog signals from the receiver coils are
The NGI operates on the principle of . Water, oil, and gas have distinct relative permittivities (dielectric constants) at high frequencies:
, the tool enables more accurate calculations of water and hydrocarbon saturation, leading to better reserve estimates.
Implementing the NGI tool in a logging program provides operators with several distinct advantages: 1. Accurate Thin-Bed Resolution
The Schlumberger NGI tool has a wide range of applications across various drilling and exploration environments. Some of the key benefits include: A horizontal well targeting a 10-foot porous dolomite zone
While the Schlumberger NGI tool has revolutionized subsurface evaluation, there are still challenges to be addressed. Some of the key challenges include:
The NGI is designed for efficient deployment and faster logging speeds without compromising image quality. Conclusion
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