Catálogo de publicaciones - libros

The concept of state vector stems from statistical physics, where it is usually used to describe activity patterns of a physical field in its manner of coarsegrain. In this paper, we propose an approach by which the state vector was applied to describe quantitatively the damage evolution of the brittle heterogeneous systems, and some interesting results are presented, i.e., prior to the macro-fracture of rock specimens and occurrence of a strong earthquake, evolutions of the four relevant scalars time series derived from the state vectors changed anomalously. As retrospective studies, some prominent large earthquakes occurred in the Chinese Mainland (e.g., the M 7.4 Haicheng earthquake on February 4, 1975, and the M 7.8 Tangshan earthquake on July 28, 1976, etc) were investigated. Results show considerable promise that the time-dependent state vectors could serve as a kind of precursor to predict earthquakes.

The general characteristics of the recent horizontal crustal movement in the Chinese Mainland and the horizontal crustal movements before the Kunlun Mountain earthquake of M8.1 on Nov. 14, 2001 and two earthquakes of M 8.0 and M 7.9 occurred in Sept. 2003 around the Chinese Mainland are analyzed with GPS data obtained in the Crustal Movement Observation Network of China (CMONOC). Relative vertical displacements observed in the last five years at fiducial stations show that there was a significant correlation between the length of day and the vertical displacements at most stations in western China.

Geological sequestration of CO (carbon dioxide) shows great potential to reduce Greenhouse gas emissions. However, CO injection into geological formations may give rise to a variety of coupled chemical and physical processes. The thermo-hydro-mechanical (THM) impact of CO injection can induce fault instability, even possibly lead to seismic activities in and around the disposal reservoir. A sequential coupling approach under some assumptions was proposed in the numerical study to investigate the THM behavior of the CO sequestration system concerning the temperature, initial geological stress, injection pressure and CO buoyancy. The fault was treated as a flexible contact model. The effects of CO injection on the mechanical behavior of the faults were investigated. The Drucker-Prager model and the cap model were used to model the constitutive relationship of formations. The numerical results show that injection pressure sensitively affects the relative slip change of the fault. At the initial stage of the sequestration process, the injection pressure plays a key role in affecting the pore pressure of the formations. However, as time continues, the influence of CO-induced buoyancy becomes obvious on the pore pressure of the formations. In general, The THM effects of CO geosequestration do not affect the mechanical stability of formations and faults.