Localized Enhancement of Infrared Radiation Temperature of Rock Compressively Sheared to Fracturing Sliding: Features and Significance

Abstract

Previous experiments indicated that infrared radiation temperature (IRT) was applied in monitoring rock stress or rock mass fracturing, and abnormal IRT phenomena preceding rock failure or tectonic earthquakes were frequently reported. However, the characteristics of IRT changing with rock fracturing and frictional sliding are not clear, which leaves much uncertainties of location and pattern identification of stress-produced IRT. In this study, we investigated carefully the localized IRT enhancement of rock compressively sheared to fracturing and sliding (named as CSFS) with marble and granite specimens. Infrared thermogram and visible photos were synchronously observed in the process of rock CSFS experiment. We revealed that localized IRT enhancement was determined by local stress locking, sheared fracturing, and frictional sliding, and the relations between the Kcv of IRT and the shear force are almost linear in wave length 3.7–4.8 μm. In the process of rock CSFS, the detected ΔIRT which resulted from thermoelastic effect is 0.418 K, while the detected ΔIRT resulted from friction effect reaches up to 10.372 K, which is about 25 times to the former. This study is of potential values for infrared detection of rock mass failure in engineering scale and satellite remote sensing of the seismogenic process in the regional scale.

Screening and rooting the multiple anomalies of Nepal earthquake sequence in 2015 with DTS criterion and homologous LCAI-coupling physics

“…TIR radiation was observed not only on the fracturing surface (3.6-14 μm) (Wu et al, 2000(Wu et al, , 2006a(Wu et al, , 2006bLiu et al, 2004;Ma et al, 2008;Zhou et al, 2019) but also on the free end (8-12.5 μm) (Freund et al 2011) of the compressed rock using infrared imager or spectra-radiometer in laboratory, which could be attributed partly to a synergic physics (Liu et al, 2021) including the recombination of P-holes (Freund 2007). TIR anomalies Zhang et al, 2017) were the earliest to be observed by satellites (between 8-12.5 μm) before the Gorkha earthquake.…”

Scrutinizing and rooting the multiple anomalies of Nepal earthquake sequence in 2015 with the deviation–time–space criterion and homologous lithosphere–coversphere–atmosphere–ionosphere coupling physics

“…TIR radiation was observed not only on the fracturing surface (3.6-14 µm; Wu et al, 2000Wu et al, , 2006aLiu et al, 2004;Ma et al, 2008;Zhou et al, 2019) but also on the free end (8-12.5 µm;Freund, 2011) of the compressed rock using an infrared imager or spectra-radiometer in the laboratory, which could be attributed partly to a synergic physics (Liu et al, 2021) including the recombination of P-holes (Freund, 2007). TIR anomalies (Lu et al, 2016;Zhang et al, 2017) were the earliest to be observed by satellites (between 8-12.5 µm) before the Gorkha earthquake.…”

Experimental Study on Damage Properties of Granites Under Flowing Acid Solution

“…The macroscopic physical-mechanical state of granite is closely related to its own microstructure change (Zhao et al, 2017b; Dong et al, 2019;Zhou et al, 2019;Liu et al, 2021a). The test analyzed the differences in apparent morphological damage and pore structure of the samples before and after immersion treatment in acidic hydro-chemical solution with different flow rates and pH values through scanning with an electron microscope at a magnification of 500 times.…”