摘要
Now as to geodetic application,constraint conditions of no-net-rotation(NNR) has been recommended and adopted by IERS organization in defining the Earth reference system,while to geophysical application,absolute plate motion models and data relative to NNR reference datum may bring misguide to mantle convection and other research.Considering hotspot relative motion,the Medial Hotspot(MHS) reference datum has been proposed,and its constraint rule has been given.Two absolute plate motion models designated as MHS-NUVEL1A and MHS-ITRF2005 have been developed using a set of hotspot data globally distributed in conjunction with plate motion models NNR-NUVEL1A and ITRF2005VEL,respectively,which were also compared with other absolute plate motion models based on the hotspots reference frame.The net rotation of the lithosphere was discussed and compared at last.The results show that the lithosphere has a net rotation relative to the hotspots by 0.26°/Ma about a pole of 50°S,62°E with respect to the deep mantle,which is closer to that from the plate forced model in direction,faster in the rate by 10%.