First Arrival Picking of Seismic Data Based on Trace Envelope

Abstract

We introduce a new method for first arrival traveltime picking based on the maximum difference between adjacent points of the envelope (MDPE) of a seismic trace. The method starts by calculating the Hilbert transform of the seismic trace to generate the complex seismic trace, which consists of the real and imaginary parts of a seismic trace. After generating the complex seismic trace, the instantaneous amplitude or envelope is extracted and used to pick the first arrival traveltime. We test the proposed method on synthetic shot records. When we compared the automatically picked first arrival traveltimes using our proposed method versus those picked manually by an experienced processor, we found that our proposed method estimated the first arrival traveltimes with more than 88% picking accuracy (within 0.1 s of manual picks). Furthermore, we perform the same test on real shot records and the proposed method estimated the first arrival traveltimes with a picking accuracy of 85% (within 0.1 s of manual picks). Finally, we apply the proposed method on 58 traces extracted from a real 2D land seismic data set from southeast Texas on which first arrival traveltime was difficult to pick automatically. We compare our proposed method and the P-phase picker method against manual picks. Results show that the proposed method has a picking accuracy of 99%, while the P-phase picker method gives 83% picking accuracy (within 0.1 s of manual picks).

Keywords

• Complex seismic trace
• envelope
• first arrival traveltime picking
• Hilbert transform
• instantaneous amplitude