Free Online Synthetic Seismogram Studio: Logs to Ricker Wiggles
Paste your log as one line per point: depth in meters, P velocity in m/s, density in g/cc. Each line marks the top of a layer.
Why synthetics matter
A synthetic seismogram is the handshake between the well and the seismic section: it takes what the borehole measured, velocity and density against depth, and predicts what the seismic survey should have recorded at that spot. When the synthetic wiggles line up with the real traces, you know which reflection is which formation, and every horizon you pick afterward inherits that confidence. This studio performs the whole classical chain: impedance from velocity times density, reflection coefficients at every layer boundary, conversion from depth to two way time, and convolution with a Ricker wavelet at the frequency you choose.
Using the studio
Each line of input marks the top of a layer with its P velocity and density. The tool computes the impedance ladder, places a reflectivity spike at each interface in two way time, and convolves. Slide the wavelet frequency and watch resolution change live: at 30 hertz the demo layers stand apart cleanly, drop toward 10 and the reflections begin to merge, exactly the tuning behavior the quarter wavelength rule predicts. Positive reflections kick to the right, the normal polarity convention.
Reading the panels
The impedance panel shows the ladder the earth presents to the wavefront: each step is a potential reflector, and the size of the step controls the strength of the reflection. The reflectivity panel is the earth stripped of the wavelet, the ideal spike series that deconvolution chases. The synthetic panel is what a noise free survey would see. Comparing the three teaches the core lesson of reflection seismology: the section is not the geology, it is the geology convolved with a wavelet, and thin beds live or die by frequency.
Where the numbers come from
With logs from a LAS file, run them through the LAS viewer next door to check quality first, then paste depth, velocity, and density columns here. Velocities from a checkshot or the velocity converter work as well. The demo layers are the same subsurface used by the seismic wave simulator, so you can watch the wavefield version and the convolution version of the same earth side by side.
Related Calculators and Reference
- LAS File Viewer: inspect the logs before you tie them.
- Seismic Wave Simulator: the same layers as propagating physics.
- The Ricker Wavelet: the pulse doing the convolving.
- Reflection Coefficient: the equation at every interface.
- SEG Wiki: the deep end of synthetic seismogram theory.