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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS011 Poster presentation 2139
The Joint Inversion Study on the Driving Forces Acting on the Block
Boundaries and Tectonic Stress Field of China Mainland and Its Adjacent
Areas
Dr. Zhixing Du
Key Laboratory of Foundational Geo-information Shandong University of Science &
Technology IASPEI
Fanlin Yang, Xiushan Lu
China situates on the southeast of Eurasian plate. It is joined with the Pacific-oceanic plate in the east
and with the Indian plate in the south. The development and interaction of three plates shape the
present tectonic framework. As one of the most drastic districts of new global tectonic change and
present tectonic motion, it is an uncommon and superior district to study the inner continent and its
marginal lithosphere and geodynamics. It plays an important role in geoscience study and is broadly
concerned by geoscience scientists. In recent decades, geoscience scientists did a lot of work in the
fields of tectonic structure, geophysical field, infrastructure, seismic activity and tectonic motion. It
established a good base for the study of driving source of tectonic motion of inner block. This paper
after expatiating the status and evolution of the inversion study on the driving forces acting on the
boundaries of China mainland and its adjacent areas and the tectonic stress field, the inversion
computation of them is made by means of the finite element of genetic method according to the
displacement observations obtained from the Crustal Movement Observation Network of China and
tectonic stress fields, and the specific implementation procedure including the selection of the
parameters, the computation conditions of model, the method of inversion, the analysis of inversion
results and their interpretation for inversion computation is given out in detail. The following conclusions
can be drawn from analyses: (1) the main driving forces that formed the displacement field in Chinese
mainland and tectonic stress field are still from the collision of Indian plate with Eurasian plate. (2)
Although the driving forces of Pacific plate and Philippine plate are smaller than that of Indian plate, yet
they are the significant factors that affect eastern China. (3) The back basin of Japan sea arc is
continuously extending possibly because of the drag to continent formed after the oceanic crust
dropped back. (4) The forces form north prevent the northern motion of China which are relatively big
resistive forces. (5) Neijiang river fracture and Xilamulun river fracture has the sign of motion, but the
exact motion mode is still uncertain.
Keywords: tectonic stress fields, crustal movement observation, joint inversion