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The Qitianling granite batholith (QGB) is located in the southern Hunan Province, middle part of the Nanling Range, South China. Its total exposure area is about 520 km 2 . Based on our 25 single grain zircon U-Pb age data and 7 published data as well as the geological, petrological, and space distribution characteristics, we conclude that QGB is an Early Yanshanian (Jurassic) multi-staged composite pluton. Its formation process can be subdivided into three major stages. The first stage, emplaced at 163-160 Ma with a peak at about 161 Ma, is mainly composed of hornblende-biotite monzonitic granites and locally biotite granites, and distributed in the eastern, northern, and western peripheral parts of the pluton. The second stage, emplaced at 157-153 Ma with a peak at 157-156 Ma, is mainly composed of biotite granites and locally containing hornblende, and distributed in the middle and southeastern parts of the pluton. The third stage, emplaced at 150-146 Ma with a peak at about 149 Ma, is mainly composed of fine-grained (locally porphyritic) biotite granites, and distributed in the middle-southern part of the pluton. Each stage can be further disintegrated into several granite bodies. The first two intrusive stages comprise the major phase of QGB, and the third intrusive stage comprises the additional phase. Many second stage fine-grained granite bosses and dykes intruded into the first stage host granites with clear chilling margin-baking phenomena at their intrusive contacts. They were emplaced in the open fracture space of the earlier stage consolidated rocks. Their isotopic ages are mostly 2-6 Ma younger than their hosts. Conceivably, the time interval from magma emplacement, through cooling, crystallization, solidification, up to fracturing of the earlier stage granites cannot exceed 2-6 Ma. During the Middle-Late Jurassic in the Qitianling area and neighboring Nanling Range, the coeval granitic and basic-intermediate magmatic activities were widely developed. It indicates that the Early Yanshanian period was the culmination time of magmatic activities in this region. The Nanling Range was under a post-orogenic, intracontinental geotectonic environment with an obvious lithospheric extension and thinning. The crust-mantle interaction played an important role in formation of granitic rocks in this region.

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Comparing with traditional fixed formation for a group of dynamical systems, time-varying formation can produce the following benefits: i) covering the greater part of complex environments; ii) collision avoidance. This paper studies the time-varying formation tracking for multiple manipulator systems (MMSs) under fixed and switching directed graphs with a dynamic leader, whose acceleration cannot change too fast. An explicit mathematical formulation of time-varying formation is developed based on the related practical applications. A class of extended inverse dynamics control algorithms combining with distributed sliding-mode estimators are developed to address the aforementioned problem. By invoking finite-time stability arguments, several novel criteria (including sufficient criteria, necessary and sufficient criteria) for global finite-time stability of MMSs are established. Finally, numerical experiments are presented to verify the effectiveness of the theoretical results. (Z.-H Guan).1 required without losing system stability, which products the following benefits: i) covering the greater part of complex environments; ii) collision avoidance. However, to the authors' knowledge, the mathematical formulations of time-varying formation tracking are still not clear, which impedes the development and applications of the relative technologies.On the other hand, networked robotic systems have been broadly studied due to their various advantages, including flexibility, adaptivity, fault tolerance, redundancy, and the possibility to invoke distributed sensing and actuation [21]. Many control algorithms for global asymptotic tracking of networked robotic systems described by Euler-Lagrange systems can be found in the literature. Adaptive control approaches are proposed to address the leader-follower and leaderless coordination problems for multi-manipulator systems based on graph theory [22,23]. Distributed containment control had been developed for global asymptotic stability of Lagrangian networks under directed topologies containing a spanning tree [24]. Some distributed average tracking algorithms had been developed invoking extended PI control and applied to networked Euler-Lagrange systems [25]. The task-space tracking control problems of networked robotic systems under strongly connected graphs without task-space velocity measurements had been investigated [26]. In presence of kinematic and dynamic uncertainties, task-space synchronization had been addressed for multiple manipulators under strong connected graphs by invoking passivity control [27] and adaptive control [28]. All of the aforementioned control algorithms produce global asymptotic tracking of robotic manipulators, which implies that the system trajectories converge to the equilibrium as time goes to infinity. Finite-time stabilization of dynamical systems may give rise to fast transient and high-precision performances besides finite-time convergence to the equilibrium, and a lot of work has been done in the last several years [29]-[31].Motivated b...