Rebuilding sequence numbers

Theory

A sequence number is a trace header value in seismic data that gives each trace a unique order or identity — e.g.,

• Trace number within file/line/reel
• Trace number within shot/record (ensemble)

It ensures each trace can be located, sorted, and processed correctly.

This module rebuilds SOURCE_SEQ, RECEIVER_SEQ & BIN_SEQ numbers ONLY.

Why it’s Important

• Maintains trace order and uniqueness
• Needed for sorting, stacking, binning, and QC
• Prevents confusion after merging or editing data
• Ensures software correctly interprets trace relationships

When to Rebuild

Rebuild (renumber) sequence numbers when:

• Traces are deleted, merged, or resorted
• Files are concatenated (duplicates/gaps appear)
• Format conversion breaks numbering
• Header values are corrupted or inconsistent
• You need clean, continuous, or per-ensemble numbering for processing

Input data

Input DataItem

Use trace vector on disk

this option is applicable when the input data is too big and the user used Open seismic traces/Open SEG-Y traces module. By default, FALSE (Unchecked). If TRUE(checked), provide the necessary connections/references.

Input traces data handle

connect/reference to Output trace data handle of Open seismic traces

Output traces file name

define the output trace file name.

Input trace headers

connect/reference to Output trace headers of Read seismic traces/Read SEG-Y traces or any related module.

Parameters

Header bulk size

specify total number of trace headers to read/write in a single batch as header bulk size. By default, 100000.

Settings

Auto-connection

By default, TRUE(Checked).It will automatically connects to the next module. To avoid auto-connect, the user should uncheck this option.

Number of threads

One less than total no of nodes/threads to execute a job in multi-thread mode. Limit number of threads on main machine.

Skip

By default, FALSE(Unchecked). This option helps to bypass the module from the workflow.

Output data

Output DataItem

 this sections deals with output data

Output trace headers

generates the updated output trace headers with new trace sequence numbers.

Information

There is no information available for this module so the user can ignore it.

Examples

In this example workflow, we modify the original trace header (TRACE_SEQ) for demonstrating sequence number rebuilding.

In the above workflow, we modified the trace headers by changing the existing TRACE_SEQ header for a test. QC the trace headers before and after Rebuilding sequence numbers by using QC trace geometry (CHANNEL, TRACE_SEQ).

Actions

There are no action items available for this module.

Video lesson

YouTube video lesson, click here to open [VIDEO IN PROCESS...]

Related articles

Yilmaz. O., 1987, Seismic data processing: Society of Exploration Geophysicist

* * *   If you have any questions, please send an e-mail to: support@geomage.com  * * *