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In this study, we analyze the regional GPS data of Crustal Movement Observation Network of China (CMONOC) observed from 2009–2013 using the BERNESE GPS software, and then the preliminary results of horizontal velocity field and strain rate field are presented, which could reflect the overall deformation features in the Chinese mainland from 2009–2013. Besides, the velocity error and the probable factors that could influence the estimate of long-term deformation are also discussed.

The subduction between Nubia and Eurasia and activities along the Red Sea, Gulf of Suez and Gulf of Aqaba may control the surface deformation in the north-eastern corner of the African continent. Using very few GPS stations in the Egyptian region, previous studies indicate northward motion of northern Nubia with respect to Eurasia of about 5 mm/yr (McClusky et al., 2000; Reilinger et al., 2006; Mahmoud et al., 2005). In order to constrain better the movement rate of northern Nubia and interaction between Nubia, Eurasia and Arabia plates, we are using for the first time 16 permanent GPS stations in combination with 47 non-permanent stations covering Egypt for the period 2006–2012. This paper extends the previous study (Saleh and Becker, 2013) by processing in addition to the Egyptian stations 86 permanent stations belonging to three different tectonic plates. This led to a considerably better coverage of the Sinai–Dead Sea region. This work intends to be the first comprehensive analysis of the permanent stations in combination with the various campaign data in selected regions of special interest in Egypt. The GPS sites show a relative motion between Nubia and Eurasia of about 6.5 ± 1 mm/yr, which increased toward the Hellenic trench, 8.2 ± 0.8 mm/yr in Sinai peninsula, 14.2 ± 1.4 mm/yr in the north of Arabian plate and 22.3 ± 0.7 mm/yr in eastern and central Turkey. The strain computation indicates high strain rates, where the deformation is strongly localized along the Dead Sea fault, and low to moderate strain rate in the Gulf of Suez and southern Sinai. [ABSTRACT FROM AUTHOR]

The dense-pack grid is commonly used to get a synoptic view of the sub-photospheric dynamics when using ring diagram analysis (Haber et al 2002). This grid is based on a fixed distribution of patches in central meridian distance (cmd) at all latitudes. A shortcoming of the dense-pack grid is that the true motion of tracked areas at slower rotating latitudes is not handled correctly. For instance, a 15° × 15° area, centered at a cmd of 0° and a latitude of 60°, that rotates only 12° in 1664 minutes (ring day), is considered tobe centered at cmd = 15° in the subsequent ring day. In order to avoid this issue, another distribution is suggested where the grid point in central meridian distance is latitude dependant (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]