地震發生時，所產生的能量與預期所要釋放出的能量低，因而，有自然學家推論地震發生時，滑動層中應存在單層的奈米級顆。而奈米級顆粒的存在，能使地震發生時所磨擦的能量減少。而本篇論文，發現到在921地震的滑動層中的確存在奈米級的顆粒，而奈米級的顆粒的最多的分佈範圍在10nm~40nm之間。另外，在X-光的繞射分析中，發現在滑動層中和滑動層的外圍的稜鐵礦(FeCO3)的強烈變化。在滑動層中，稜鐵礦在滑動層中，稜鐵礦幾乎消失不見，而碳酸鈣在地震的過程中，並沒太大變化，所以，推論在地震發生時滑動層當時的溫度介於兩者熔解溫度之間(580℃~894℃)。 Atomic force microscopy (AFM) and General Structure Analysis System (GSAS) program have been used to investigate the nanometric characteristics of the fault gouge in the 223.45 m cores of Chi-Chi earthquake. Nano grains were revealed in the slip zone, with a mean diameter is ~20nm, while only μm grains were found outside the slip zone. X-ray diffraction patterns were refined following the Reiveld refinement method and reveal three main structural phases, namely quartz (hexagonal P6222 symmetry of SiO2), siderite (R-3CH symmetry of FeCO3), and calcite (R –3cRS symmetry of CaCO3), respectively. Among them, FeCO3 shows a rapidly percentage reduction from being at 35% to at 4 % as the specimen were taken from depths of 223.37 m (outside of the fault gouge) to 224.45 m (the fault gouge), while the composition of CaCO3 remains essentially unchanged. This founding can be used as an indicator for the temperature of the slip zone during the earthquake.
