Multi-component digital-based seismic landstreamer and boat-towed radio-magnetotelluric acquisition systems for improved subsurface characterization in the urban environment

摘要

It is estimated that urban life will be the norm for around 60% of the world's population by 2040, leading to a more centralized distribution of people and making the city as the main place of residence (Whiteley, 2009). This population centralization inherently implies rapidly expanding cities and imposes the need for more infrastructure within, around and between the present city boundaries. However, infrastructure projects nowadays have to follow strict civil engineering standards that require detailed knowledge of subsurface conditions during different stages of the construction processes. Since direct methods conventionally used for site characterization (e.g., drilling and/or core testing) are still relatively expensive the focus in the last two decades has been on non-invasive, geophysical methods. However, geophysical site characterization in urban areas is not an easy task owing to numerous challenges and various types of noise sources. Challenges such as electric/electromagnetic (EM) noise, pipelines and other subsurface objects (sometimes even unknown or undocumented), the inability to properly couple sensors because of pavement, traffic noises and limited space are common in urban environment. Since geophysical surveys need to be done with the least amount of disturbances to the environment, residents and traffic, new geophysical techniques for fast, non-invasive and high-resolution site characterization are needed.