An automatic horizon picker, a window extractor and a node finder for the CREWES MATLAB Library
Christopher B. Harrison
This paper covers three new programs created by Christopher Harrison for the CREWES MATLAB library. The first program is a first generation automatic horizon and event picker named PICKSLE. This program uses a windowed section on a single trace and cross correlates this area either across an entire section of data or a specified section as selected by a user. PICKSLE allows the developer or user to have control over various aspects of the cross correlation scanning process, from the percent at which the cross correlation will be checked and kept, to visualization of the programs scanning process. Depending on the parameters initially chosen by a developer or user, PICKSLE will either be slow and reasonably accurate, or fast and quite possibly inaccurate. This program is still under development, but is usable in its present configuration.
The last two smaller programs were specifically developed for use with PICKSLE, but as development progressed it became apparent that their potential could benefit other programs. The first of these smaller programs can be used in conjunction with other developments requiring a user to create their own windowed area on a single trace of data. The program is called WINEXTRACTOR and visualizes a single trace, an initial adjustable point of clicking, and two adjustable windowed areas. These attributes, along with several other predefined or user-selected arguments allow for user to adjust a precise window area on an input trace.
The final program covered in this paper is utilized by both the above programs in restricting either clicking or point movement on an input traces. The program's name is NODEFIND, and isolates points on an input trace as chosen by a user. The choices for isolation are peaks, troughs, and zero crossing points.