Some Mass Migration Underground Found in Beijing Area

Abstract

The relationship between the change of a local gravity field and the mass migration underground is discussed by means of using a point-source disturbed body as a substitute for the mass migration underground. Some significant local gravity field changes in Beijing area have been found, from which the three parameters of the disturbed bodies, location, depth and mass, have been derived successfully from the observations of a gravimetric network. In order to determine the depth of a body, a new approach is suggested in which the gravity change difference is used instead of the gravity change itself. The mass of a disturbing body has been estimated properly. Astronomical PZT is suggested for this kind of survey. The results provide us a picture of the underground mass migration with which the gravity changes on the ground surface may be interpreted in a better way. This additional information may be useful in seismological studies.

A new method of measuring gravitational acceleration in an undergraduate laboratory program

“…Zheng et al found that the timing of the two pair local gravity field change (LGFC) can be attributed to two earthquakes in the Beijing region and a related underground mass migration of up to 20 km. The left two images are the local gravity field change (LGFC) before the earthquake near Beijing in 1998, and the right two images are the ones after the earthquake [11]. about 10 m s , 7 2 -which is two orders of magnitude smaller that what can be measured with the experiment presented here in its current setup.…”

“…It is interesting to see whether our experiment, if repeated in an undergraduate experimental program year after year, can reflect changes in gravity triggered by external local events. Zheng et al [11] discussed the relationship between the change of a local gravity field and the underground mass migration in the Beijing area by means of using a point-source disturbed body as a substitute for the mass migration underground ( figure 7). Zheng et al found that the timing of the two pair local gravity field change (LGFC) can be attributed to two earthquakes in the Beijing region and a related underground mass migration of up to 20 km.…”

An empirical study of public spiritedness among university students

“…The cultivation of public spirit needs to be gradually trained in specific situations, and become a natural way of thinking, attitude and even behaviour through long-term accumulation. [4] More importantly, it mobilises the intrinsic motivation of students to nurture themselves [5] . Therefore, it can be said that the pedagogy of participatory experiential learning is highly compatible with the shaping of public spirit.…”