segyio

name	segyio
description	Read, write, and manipulate SEG-Y seismic data files. Fast C library with Python bindings for trace, header, inline, and crossline access. Use when Claude needs to: (1) Read/inspect SEG-Y files, (2) Extract trace data or headers, (3) Access 3D survey data by inline/crossline, (4) Create new SEG-Y files from arrays, (5) Modify existing SEG-Y files, (6) Extract subsets of seismic data, (7) Read/write Seismic Unix format.
version	1.0.0
author	Geoscience Skills
license	MIT
tags	["Seismic","SEG-Y","Data I/O","Traces","Headers","Segyio","Inlines","Crosslines"]
dependencies	["segyio>=1.9.0","numpy"]
complements	["obspy","bruges","pyvista"]
workflow_role	data-loading

segyio - SEG-Y Seismic Data

Quick Reference

import segyio

# Read
with segyio.open('seismic.sgy', 'r') as f:
    print(f.tracecount, len(f.samples))
    trace0 = f.trace[0]              # Single trace as numpy array
    data = segyio.tools.collect(f.trace[:])  # All traces

# 3D access (specify inline/xline byte locations)
with segyio.open('seismic.sgy', 'r', iline=189, xline=193) as f:
    inline_100 = f.iline[100]        # 2D array (xlines x samples)
    cube = segyio.tools.cube(f)      # Full 3D cube

# Write
spec = segyio.spec()
spec.samples = samples
spec.tracecount = n_traces
with segyio.create('output.sgy', spec) as f:
    f.trace[0] = data

Key Access Modes

Mode	Description
f.trace[i]	Sequential trace access by index
f.header[i]	Trace header access (dict-like)
f.iline[n]	Inline slice (3D surveys)
f.xline[n]	Crossline slice (3D surveys)
f.depth_slice[n]	Horizontal time/depth slice
f.text[0]	Text header (3200 bytes)
f.bin	Binary header

Essential Operations