Application of Terahertz Time-Domain Spectroscopy in Detecting Gaps with Different Widths

Abstract

The characterization of fractures is of vital importance for studies in many industries. In the present work, we used terahertz reflection measurements to identify simulated gaps of different widths that resemble fractures. The time interval between pulses (Δt) was proportional to the distance between the interfaces. In addition, fast Fourier transform (FFT) corresponding to the waveforms was also employed to distinguish the gaps. The widths in frequency were found to be inversely proportional to that of the gaps. In general, both terahertz time-domain spectroscopy (THz-TDS) and terahertz frequency-domain spectroscopy (THz-FDS) can achieve the measurement of the gaps of micro size.

Layer Caused an Anisotropic Terahertz Response of a 3D-printed Simulative Shale Core

“…Owing to the unique advantages, this technique is expected to be a "silver bullet" in various aspects of oil and gas resources, 16 especially in reservoirs and rocks. 17 At present, THz-TDS has been applied to investigating the optical properties of marble, sandstone, and limestone. 18 The dielectric properties of montmorillonite clay, 19 micaceous clay, 20 kaolinite, halloysite, 21 and clay-based polyamide nanocomposite films were measured at the THz region.…”