What Is 3D Seismic Interpretation?

In the seismic interpretation system, the process of displaying and displaying three-dimensional graphics and images of seismic data with motion and realism. 3D visualization is an evolving 3D graphics calculation, processing and display technology. Based on perspective principles, it makes full use of processing methods such as color, transparency, lighting, shadows, animation, rotation, etc. Data such as geology and geology have become a colorful three-dimensional world on the screen, which can intuitively, quickly and realistically show the structure and sedimentary characteristics of the three-dimensional space, and provide a new environment for the interpretation of seismic data. Not only has it created conditions for interpreters to easily observe and understand underground geological structures, but it has also promoted the progress of human-machine interactive interpretation of seismic data. The three-dimensional visualization techniques often used in human-computer interaction interpretation of seismic data are: animation display, combined display, color display, transparency adjustment display and engraving display. ^[1]

Due to the development of fast-screen-elimination technology and the increase of computer memory, the past flat animation display has developed into the current three-dimensional animation display. The three-dimensional cursor control can be used to flexibly perform animation display on three planes separately, which lays the foundation for fast and dynamic viewing of the data volume in any direction (longitudinal line profile, horizontal line profile, time slice).

Three-dimensional visualization technology makes the display of various forms of data faster and easier. Today's combined displays can be summarized into four scenarios:

(1) A combined display within a data body, including vertical surveys of special surveys (such as parallel surveys, radial surveys, and fan surveys), and connection displays (such as any flexed vertical profile, cylindrical vertical profile, grid profile, Chair-shaped display and grid-shaped display connected to sections and slices), docking display (such as box display and corner display), data volume cutting display (such as rectangular body cutting, drawer cutting, curved surface cutting, block cutting, oblique cutting );

(2) Combination display of multiple attribute data bodies, including superimposition (overlap) display of two attribute bodies, mosaic display of 2 to 3 attribute bodies, and fusion display of multiple attribute bodies;

(3) Combined display of multiple types of data, including combined display of seismic, drilling, logging, geological and geographic information, combined display of various sections, planes, and three-dimensional maps;

(4) Multiplexed area data combination display, including 2D and 3D multiple work area or 3D multiple work area combined display.

Color has always played a very important role in the visualization of seismic data. Based on the principles of RGB (red, green, and blue) and HSV (chroma, saturation, and darkness), a variety of colors can be generated with a computer. The appropriate variable density or gradient color scale is configured in 256 commonly used colors, and the necessary linear or non-linear adjustments are made, which can highlight the characteristics of the data and facilitate the understanding of underground geological laws. Real-time, convenient and flexible adjustment, deletion, saving and recall of the colors in the color scale can make the color display play a better effect in the interpretation of seismic data.

The transparency of data processing has the ability to see through the data. By properly adjusting the transparency curve and color scale to process the seismic data, not only the perspective effect is improved, but also the depth of field is increased. Highlight the geological features of three-dimensional space.

Part of the data body of interest is stripped from the big data body (parent) to form a single target data body (usually called the child in software), which is recorded in a file and displayed. Commonly used engraving methods are horizontal engraving, layer engraving, and layer engraving along two levels. The key of engraving display technology is the thickness, color selection and transparency adjustment of sculpting body.

Three-dimensional visualization of seismic data has been fully applied in seismic data interpretation. Based on this, virtual reality visualization and 3D visualization technology for seismic data processing and interpretation on a PC cluster are being developed. ^[2]