Composite Metallogenic Systems in the Weihai Area of Shandong and Evolution of Continental Dynamic Regimes

Based on 9 sheets of 1：50,000-scale regional geological survey and guided by the theory of metallogenic systems and integrated analyses of the structural and metallogenic features, this paper hereby puts forward the composite metallogenic systems of the Weihai area, Shandong Province, aiming at solving the problems on the origins and ore-controlling structures of the numerous deposits in the area. Its scientific significance is reflected in the following three aspects： （1） The basic features of the composite metallogenic systems can be recognized, which consist of two types： the Proterozoic metamorphic-hydrothermal metallogenic system and the Mesozoic magmatic-hydrothermal metallogenic system （i.e. the Indosinian-early Yanshanian contact metasomatic metallogenic series and the mid-late Yanshanian magmatic-hydrothermal metallogenic series）. The two series display arcuate and NW-right lateral arrangements and a N-S parallel zonal distribution respectively, with the corresponding mineral assemblages being Au＋Ag＋Pb＋Zn, etc.; and Cu＋Mo＋Fe, Au＋Ag＋Cu＋Pb- Zn＋Mo＋Co-Ni＋sulfides＋silicides＋K-feldspar, etc. （2） The composite metallogenic systems may be used to interpret the complicated genetic relations of the deposits. Through analyses of the relations between the three main metallogenic intervals and their corresponding source rock series （the Jingshan and Rongcheng groups; the Wendong super-unit and the early-middle Yanshanian Weideshan super-unit; and the mid-late Yanshanian Weideshan and Laoshan super-units） as well as a case study of the Fanjiabu gold deposit, we have distinguished the consanguinity between the contact metasomatic （skarn-type） metallogenic series and the magmatic-hydrothermal metallogenic series as well as the noncognate superposition between the two and the metamorphic-hydrothermal metallogenic system. （3） The composite metallogenic systems are easily related to the evolution of continental dynamic regimes. The formation of the metamorphic-hydrothermal metallogenic system has undergone transformations of three different types of tectono-dynamic regimes from extension→compression→ shearing; that of the contact metasomatic （skarn-type） metallogenic system from compression→extension→compression; and that of the magmatic-hydrothermal metallogenic system from extension →subductive compression of the Pacific Plate. The evolutions of the three types are all attributed to the opening-closing or divergence-convergence of the paleocontinent, and all their mineralization corresponds to the interval of transformation from the end of convergence to early integration of the Weihai paleocontinent. All these will benefit our deeper study of the dynamics of continental metallogenic processes.

Effective Lifetime Experimental Measurement under External Magnetic Field in Transient Dynamic State by Open Circuit Voltage Decay Method

In this work, we present an experimental transient 3-Dimensionnal study for the minority charge carriers’ effective lifetime measurement under magnetic field in transient dynamic state. The magnitude of the magnetic field B is varied from 0 mT to 0.03 mT. The method used is mainly based on the open circuit voltage decay method. The solar cell is injected by a low electrical excitation which protects against capacitance effects. Our approach is based on the open circuit voltage decay response analysis. From an experimental set-up, we get the transient voltage data on a digital scope. The data are used for plotting transient voltage decay curves. The curves obtained and analyzed are fitted in their linear zone. This zone presents an ideal decay which permits to get good values of lifetime. The slope of the linear decay is inversely proportional to effective lifetime. The results of fitting permit determinate the effective charge carriers’ lifetime directly. The results obtained are then presented and analyzed. The observations indicate that the charge carriers effective lifetime decrease when the magnetic field increases.

Mantle dynamics of the reactivating North China Craton:Constraints from the topographies of the 410-km and 660-km discontinuities

The topographies of the 410-km and 660-km discontinuities have important implications for mantle dynamics.Here we present high-resolution seismic imaging of the 410-km and 660-km discontinuities beneath the North China Craton (NCC) employing the receiver function method.Depth anomalies (deeper or shallower than the global average depths) at both discontinuities were detected by introducing a three-dimensional regional velocity model.The depressions of the 410-km discontinuity are mostly located in the eastern NCC.A local elevation of the 660-km discontinuity appeared in the northwest of the NCC and a significant depression of the 660-km discontinuity is located in the southeast of the NCC.Two dynamic mantle regimes are speculated to explain the formation of the anomalous depth zones in the NCC.One possibility is a complex mantle upwelling linked to edge-derived convection between the stagnant slab and the thick cratonic root.The other potential dynamic regime is slab stagnating,sinking,and induced upwelling at the neighboring slab front.These regimes hint that the mantle flow was possibly dominated by dynamic interactions among the subducting slab,cratonic root,and ambient mantle beneath the NCC.

Dynamical Criticality:Overview and Open Questions

Systems that exhibit complex behaviours are often found in a particular dynamical con- dition, poised between order and disorder. This observation is at the core of the so-called criticality hypothesis, which states that systems in a dynamical regime between order and disorder attain the highest level of computational capabilities and achieve an optimal trade-off between robustness and flexibility. Recent results in cellular and evolutionary biology, ueuroscience and computer science have revitalised the interest in the criticality hypothesis, emphasising its role as a viable candidate general law in adaptive complex systems. This paper provides an overview of the works on dynamical criticality that are -- To the best of our knowledge -- Particularly relevant for the criticality hypothesis. The authors review the main contributions concerning dynamics and information processing at the edge of chaos, and illustrate the main achievements in the study of critical dynamics in biological systems. Finally, the authors discuss open questions and propose an agenda for future work.

Deep advantage learning for optimal dynamic treatment regime

Recently deep learning has successfully achieved state-of-the-art performance on many difficulttasks. Deep neural networks allow for model flexibility and process features without the needof domain knowledge. Advantage learning (A-learning) is a popular method in dynamic treatment regime (DTR). It models the advantage function, which is of direct relevance to optimaltreatment decision. No assumptions on baseline function are made. However, there is a paucityof literature on deep A-learning. In this paper, we present a deep A-learning approach to estimate optimal DTR. We use an inverse probability weighting method to estimate the differencebetween potential outcomes. Parameter sharing of convolutional neural networks (CNN) greatlyreduces the amount of parameters in neural networks, which allows for high scalability. Convexified convolutional neural networks (CCNN) relax the constraints of CNN for optimisation purpose.Different architectures of CNN and CCNN are implemented for contrast function estimation.Both simulation results and application to the STAR*D (Sequenced Treatment Alternatives toRelieve Depression) trial indicate that the proposed methods outperform penalised least squareestimator.

Landmarks in the application of electrical tomography in particle science and technology

Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. The ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications. Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion.