INTRODUCTION
The SCAN Tool incorporates state-of-the-art wellbore acoustics theory and measurement technology to deliver highly accurate acoustic data in through-casing applications. The SCAN tool locates Water-Oil-Gas fluid contacts and corresponding saturation when combined with the MDNT (Memory Dual Neutron Tool). The acoustic-based SCAN tool is unaffected by casing hardware and has a deep depth of investigation.
The velocity of compressional and acoustic waves can be used to determine the type of saturation fluid, and is most effective in less well-consolidated formations. In these sediments, the compressional wave velocity is strongly influenced by the type of saturating fluid. The shear velocity is unaffected.
DESCRIPTION
The tool is a multi-receiver 1 11/16" acoustic tool designed to investigate through-tubing fluid contacts, by measuring P- and S-wave reflections from the fluid formation.
FEATURES
- High energy pulsed-power transmitters
- Low frequency/high energy (deeper penetration/stronger signal)
- Downhole automatic gain control
- Multiple presentation formats
| Tool Outside Diameter | 40 mm (1.6 in) |
| Length | Variable (depending on configuration) |
| Maximum Temperature | 150 °C |
| Maximum Pressure | 200 bars |
| Variable Spacing | All traces synchronously and simultaneously recorded |
| Sonic Wave Frequency | 15 - 25 kHz |
| Sonic Wave sampling rate | Configurable, 2 - 50 msecs |
| Sonic Wave Length | Configurable, up to 1024 samples per receiver |
| Dynamic range | 12 bits plus 4 bits gain (configurable) including AGC |
| Data communication | High Speed telemetry |
Modular tool allowing a configuration of up to 2 transmitters and 8 receivers:
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LOG-MEASUREMENT SPECIFICATIONS
- Minimum Borehole Diameter: 4.5 in (114 mm)
- Maximum Borehole Diameter: 21 in (533 mm)
- Recommended Logging Speed: 5 - 10 ft/min high resolution mode
- Lower Porosity Limit: 14%
- Transmitter Firing: 1 or 2 per second
- Oil-Water contact determination limits: 40 API
- Resolution: 1/8 of a wavelength
APPLICATIONS
- Through-tubing identification of Water-Oil-Gas contacts
- Lithology and Hydrocarbon typing
- Waterflood/supplemental recovery surveillance
- Volumetrics (porosity/water saturation) behind the casing
- Direct measurement of rock mechanical properties (elastic moduli/compressibilty)
- Highly accurate measurement of compressional, shear and stoneley wave velocities/travel times
RESERVOIR FLUID IDENTIFICATION
The crossplot of Vp/Vs vs Dt shear has proven to be a hydrocarbon indicator in homogeneous plastics. This technique is based on the principle that formation compressional travel times are reduced in relation to the compressible reservoir fluid saturation, while shear travel times remain generally unchanged.
View Acoustic Lithology and Porosity chart in PDF format
View Shear Wave and Porosity relation in PDF format
If you are interested in this service, please fill out our Service Request Form, and we will get back to you promptly.
