Technical feasibility study of a mini vibrating source (vibro) for high resolution seismic data acquisition

• Grant number: 15/15988-7
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• Start date: June 01, 2016
• End date: February 28, 2017
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geophysics
• Principal Investigator: Nilton Silva
• Grantee: Nilton Silva
• Company: TEC3GEO - Geotecnologias Inovativas Ltda
• City: São Paulo
• Pesquisadores principais: Guilherme Do Carmo Novaes
• Associated researchers: Francisco Yukio Hiodo ; Renato Luiz Prado
• Associated research grant(s): 17/03416-4 - High resolution shallow seismic instrumental: minisource and seismograph, AP.PIPE
• Associated scholarship(s): 16/04422-5 - Technical feasibility study of a mini vibrating source (vibro) for high resolution seismic data acquisition, BP.PIPE; 16/04421-9 - Technical feasibility study of a mini vibrating source (vibro) for high resolution seismic data acquisition, BP.PIPE

Abstract

In the studies of subsurface of urban areas usually is used as shockwave source a sledgehammer or falling some heavy thing, over a metallic plate. However, there is almost no repeatability of the seismic sign generated, as in not possible to use in areas with areas with coated floor. A controlled seismic source of high frequencies has many advantages over the impulsive sources with respect to a: i) sweep - source energy distribution avoids inelastic deformations in the vicinity of the source; ii) frequency range can be controlled in order to increase the resolution, or the optimization of the depth of research; iii) portability - no restraint for use on any paved surfaces. In addition to these advantages, there is the possibility of using the seismic reflection wave S, very difficult to be undertaken properly with impulsive source. The use of S waves allows: i) better correlation of speeds with NSPT indices; ii) an increase of vertical resolution due to the speed difference between P and S waves; iii) mapping of different geotechnical saturated horizons due to the "insensitivity" of S waves and the water table and iv) in many cases, better signal to noise ratio due to higher amplitude of the S waves. So the minifont vibrating, as used in oil exploration, potentially represents an interesting alternative in seismic survey in urban areas. This proposal is in line with another project at an advanced stage of Tec3GEO, a low cost seismograph to shallow research. In its first release this digital seismograph, scheduled for 2016, will have digital scanning modules with internal geophones for each measurement point; the transmission of seismic signals will be by simple digital cable. The availability of a seismograph and a controlled seismic source to the market is a major competitive advantage. This pair, controlled and digital seismograph seismic source, represent a complete solution for shallow geological and geotechnical investigation of high resolution with the use of seismic methods. This Innovative Program representation a great opportunity to meet pent-up market demand, considering the scarcity of Technology Companies instrumental and geoenvironmental Geophysics today. However, the vibrating minisource proposed in this project feasibility studies, it is an innovation with competitive advantages, regardless of proposition of Tec3GEO seismograph. The high-resolution shallow seismic is a front of important research today in both the instrumental development (minisource) as the techniques of acquisition and seismic processing. Thus, this proposal has the scientific collaboration of Prof. Dr. Renato Luiz Prado and Prof. Dr. Francisco Yukio Hiodo, teachers of the Department of Geophysics of IAG -USP. This Department has extensive experience in the use of seismic methods and a digital reference seismograph that can be used to validate the results of the study. (AU)