Contact Us

Schlumberger
DeepLook-CS
Crosswell Seismic Imaging
8020 Leghorn, Suite B
Houston, Texas 77040
Call Us
T: 1 713 690 5880
F: 1 713 690 5970
Get In Touch
Contact Form

Related Site

Related Content

Crosswell Seismic Imaging Operations

Data Matched To Your Operation

A Crosswell Seismic Imaging project is separated into two segments: field acquisition and data processing. Using a system refined over thousands of operations, these segments deliver the most detailed, high-resolution data matched to the information requirements of your operation.

Field Acquisition

Crosswell Seismic Imaging operations normally involve accessing two or more wells simultaneously: A downhole seismic source is lowered into the bottom of one well, and a receiver array string is lowered into the bottom of one or more adjacent wells. Very high bandwidth sound waves (typically 100 to 2000 Hz) are transmitted from the source to the receivers as the source is moved up the wellbore (Fig-1, Fig-2). The receiver array is then moved one array length up the wellbore, and the source again transmits sound waves as it travels up the wellbore (Fig-3). This process is replicated (Fig-4) until all areas of the reservoir are covered vertically, ensuring that seismic data are fully collected between the wells directly across the reservoir or other zones of interest.

Crosswell Imaging acquisition techniques are equally applicable to open holes and new field developments as well as cased holes. For maximum efficiency, field units equipped with dual acquisition computers and dedicated quality control workstations provide crews with the ability to control data quality in real time.

Reliable High Performance Source and Receiver Systems

Utilizing unique technology, our Crosswell sources are able to distribute energy over a large area in the wellbore. To ensure reliable operations under a wide variety of wellbore conditions, these sources are constructed of corrosion-resistant stainless steel and feature high temperature components. The sources are also equipped with active pressure compensation for additional reliability. The active-array receiver system incorporates a field-proven design to deliver reliable data imaging in vertical and deviated wells, as well as in open and cased holes.

Data Processing

Crosswell Seismic Imaging’s highly complex recorded data field contains in-depth information about the reservoir’s properties and structure, allowing for optimum characterization of the Crosswell space. The first processing step employs travel time inversion (Crosswell tomography) to yield a velocity map between the wells - basically, a Crosswell “sonic log” of the reservoir. This tomogram is directly referenced in depth, and is used as the base model for reflection imaging.

Subsequent processing steps include wave-field separation and mapping to produce detailed reflection images of the reservoir’s structure, similar in character to surface seismic or VSP, but at greatly increased resolution. The format of the data is industry-recognized SEGY data, allowing for easy integration into the geological model or surface seismic data of the target area.

Other information, such as shear and mechanical properties, anisotropy, and guided wave models, can also be analyzed and integrated into the overall reservoir model.