Analysis of crooked-line 2D seismic reflection data recorded in areas with complex surface and subsurface conditionsIonelia Panea 1 3 Delia Bugheanu 2
1 Faculty of Geology and Geophysics, University of Bucharest, 6 Traian Vuia Street, Bucharest 020956, Romania.
2 Faculty of Environment, University of Leeds, Leeds, LS2 9JT, UK.
3 Corresponding author. Email: firstname.lastname@example.org
Exploration Geophysics 48(4) 493-503 https://doi.org/10.1071/EG15107
Submitted: 15 October 2015 Accepted: 4 August 2016 Published: 1 September 2016
We analysed a crooked-line two-dimensional (2D) seismic reflection dataset recorded in the northern part of the Eastern Pannonian Basin using a different processing flow than the one typically used in hydrocarbon exploration studies, with the purpose of obtaining high-resolution images for the depth interval of interest. The data acquisition was done using irregular spacing between receivers and sources due to the rough topography and complicated geological structure. As an effect of data acquisition, the midpoints were spread over an area with a width of ~900 m on the central part of the seismic profile. A significant number of field records contained noisy first arrivals on the offset interval used in the computation of static corrections. We defined two types of geometry: one for a 2D crooked-line and another for a pseudo-3D survey; then, we used the same processes and parameters during processing. For the noisy field records, we used refraction interferometry (RI) by cross-correlation and convolution to enhance the first arrivals and to better control picking of the first-arrival traveltimes. We show that the continuity of the supervirtual first arrivals depends on the number of records, with noisy and clear first arrivals used as input to RI. Comparing the pre- and post-stack data, represented by filtered common-depth-point (CDP) gathers and time sections, respectively, we notice that the use of pseudo-three-dimensional (3D) geometry helps us to improve the signal-to-noise ratio (SNR) of pre- and post-stack data, and to image the main geological marker reflections in the investigated area.
Key words: head waves, processing, seismic reflection, statics.
ReferencesBharadwaj, P., Schuster, G., Mallinson, I., and Dai, W., 2012, Theory of supervirtual refraction interferometry: Geophysical Journal International, 188, 263–273
| Theory of supervirtual refraction interferometry:CrossRef |
Gierse, G., Trappe, H., Pruessman, J., Eisenberg-Klein, G., Lynch, J., and Clark, D., 2009, Enhanced velocity analysis, binning, gap infill, and imaging of sparse 2D/3D seismic data by CRS techniques: Houston, Texas: 79th Annual International Meeting, SEG, Expanded Abstracts, 3279–3283.
Hall, K. W., Lu, H., and Stewart, R. R., 2007, Crooked-line seismic data processing at Castle Mountain: CREWES Research Report, 19, 1–8.
Mikesell, D., van Wijk, K., Calvert, A., and Hancy, M., 2009, The virtual refraction: useful spurious energy in seismic interferometry: Geophysics, 74, A13–A17
| The virtual refraction: useful spurious energy in seismic interferometry:CrossRef |
Nedimović, M. R., and West, G. F., 2003, Crooked-line 2D seismic reflection imaging in crystalline terrains: part 1, data processing: Geophysics, 68, 274–285
| Crooked-line 2D seismic reflection imaging in crystalline terrains: part 1, data processing:CrossRef |
Panea, I., Stephenson, R., Knapp, C., Mocanu, V., Drijkoningen, G., Matenco, L., Knapp, J., and Prodehl, K., 2005, Near-vertical seismic reflection image using a novel acquisition technique across the Vrancea Zone and Focsani Basin, south-eastern Carpathians (Romania): Tectonophysics, 410, 293–309
| Near-vertical seismic reflection image using a novel acquisition technique across the Vrancea Zone and Focsani Basin, south-eastern Carpathians (Romania):CrossRef |