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• A generalized integer linear programming model of the PMU placement is proposed. • Topology changes are considered to guarantee the observability with multiple topologies. • The effects of existing measurements and their relevance are covered. Distribution networks usually have a meshed structure but are operated radially to improve the operating efficiency and ensure the power supply under an emergency situation. It is of great significance to guarantee the observability of the entire system under the topology changes in operation. This paper proposes an optimal placement method of phasor measurement unit (PMU) for distribution networks. A generalized binary integer linear programming (ILP) model for PMU placement is proposed. The changes in topology are considered to guarantee the observability under any possible operation mode. The existence of zero injection nodes (ZINs), the existing measurements, and their relevance are also covered in the proposed method to reduce the installed PMU number. The objective of the ILP problem is weighted by the degree of the corresponding node to obtain a scheme with higher measurement redundancy. The correctness and effectiveness of the proposed method are verified via case studies on the IEEE 33-node test feeder, PG&E 69-node test feeder, and a medium voltage distribution network in Southern China. [ABSTRACT FROM AUTHOR]

• A novel PMU-based equivalent model for voltage sensitivity estimation is proposed. • The simplified observable network is obtained with PMUs configured arbitrarily. • Multitime slots of PMU measurements are used to estimate equivalent parameters. • A robust method is exploited to handle the noise and bad data in measurements. The access and application of phasor measurement units (PMUs) in distribution networks highly improve the system observability and further enhance the performance of operation control and energy management. A novel PMU-based estimation method of voltage-to-power sensitivity via network equivalent is proposed for distribution systems. An equivalent model is introduced to simplify the PMU-unobservable parts of the distribution network. The equivalent parameters are estimated with the PMU measurements on both sides. The original PMU-unobservable distribution network is simplified into a completely observable network with an arbitrary configuration of PMUs. The maximum correntropy Kalman filter (MCKF) is exploited in parameter estimation to handle the noise and bad data within the PMU measurements. The voltage-to-power sensitivity of the simplified system is then calculated according to the estimation of the equivalent network parameters. Case studies on the IEEE 33-node and the PG&E 69-node test feeders verify the correctness and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Highlights • An analytical framework for quantifying the flexibility of ADNs was proposed. • Flexibility of network transmission was analysed with the limits of physical network. • The benefits of controllable resources for flexibility improvement were explored. Abstract With the integration of high shares of distributed generators (DGs), it is increasingly difficult to cope with the various uncertainties and puts forward higher requirements for the operational flexibility in active distribution networks (ADNs). Controllability of ADNs has been significantly improved by the application of energy storage and power electronic devices. However, due to the difficulties in effective coordination of various controllable resources, the controllability cannot be fully translated into the system flexibility. In this paper, an analytical framework for quantifying the flexibility of ADNs is proposed, including the quantification of node flexibility, the matching of system flexibility, and the flexibility of network transmission. The proposed framework provides a novel perspective of flexibility to reinterpret operation issues of distribution networks. As the power imbalance and voltage deviation are even more severe caused by the high shares of DG integration, the indexes of flexibility from magnitude, frequency and intensity dimensions are deteriorated in ADNs operation. Through the spatial and temporal regulation of power flow, various controllable devices, such as soft open points (SOPs) and energy storage system (ESS), can effectively mitigate the power imbalance and voltage deviation to improve the indexes of system flexibility. Thus, under the unified analytical framework, the potential benefits of system controllability are fully utilized to provide effective countermeasures for the flexible operation of ADNs. Finally, case studies are performed on the modified IEEE 33-node system to quantify the operational flexibility of ADNs and verify the flexibility enhancement brought by controllable resources. [ABSTRACT FROM AUTHOR]

Abstract Potential flow (PF) model exhibits some advantages to simulate granular flow in industrial packed beds such as an iron-making blast furnace. To change the status of solving PF equations in the flowing zone, based on the difference analysis between PF and actual flow, the components of granular flow resistance were confirmed, and a novel potential flow (NPF) model for the flow of packed particles was established. The obvious difference from the PF model is that the NPF model can simultaneously predict the stagnant zone and the distribution of velocities in the flowing zone. The stagnant zone or the flowing zone calculated with NPF model under certain boundary conditions is only determined by a dimensionless parameter group R ⁎ . R ⁎ has a clear physical meaning, so it's easy to decide the effect on the distribution of stagnant zone and granular flow velocities. Furthermore, NPF model was validated by experimental data obtained with a two-dimensional flat-bottomed packed bed with centric discharge. Predicted results respectively by PF and NPF models were also compared. Graphical abstract Unlabelled Image Highlights • Novel potential flow model for granular flow in packed bed was put forward. • The model results are only decided by a dimensionless group at certain conditions. • The stagnant zone and the flowing zone could be simultaneously predicted. • Predicted results accord quite well with the experimental results. [ABSTRACT FROM AUTHOR]

Highlights • A day-ahead scheduling strategy is proposed with detailed device modeling. • The effects of multiple thermal storage devices on flexibility are fully utilized. • The unit commitment constraints in practical operation are well considered. • The optimal scheduling model is transformed into a MILP formulation by linearization. Abstract The operation of community integrated energy systems (CIESs) is challenging because it is necessary to couple energy production, conversion and consumption on the end-user side. Multiple energy demands need to be fed simultaneously with the goal of economy and reliability. This paper formulates the optimal scheduling problem based on a real community integrated energy system in China. The system has multiple chillers (i.e. three ground source heat pumps, two conventional water-cooled chillers and two double-duty chillers) and two types of thermal storage devices (i.e. two cold water tanks and an ice-storage tank). Based on detailed device modeling, a community integrated energy system operation strategy considering unit commitment is proposed, and then is transformed into a mixed-integer linear programming model by linearization of nonlinear items. Case studies are conducted based on the data for a typical day in summer. The results show that the proposed strategy can utilize the flexibility of the energy storage devices and realize an economic and reliable operation of the community integrated energy system by coordinating various energy devices. The strategy can also reduce the startup/shutdown frequency of chillers significantly. [ABSTRACT FROM AUTHOR]

Highlights • A distributed network loss optimization approach is present to increase energy utilization. • A fully distributed voltage control method is proposed. • A topology simplification method with DPMU data at controllable DGs/loads is proposed. • The coordinated control system is based on incomplete measurements. Abstract This paper explores a distributed coordinated control algorithm for active distribution networks (ADNs) based on measurements of distribution phasor measurement units (DPMUs) that are only installed at a portion of network nodes. First of all, a network topology simplification method is proposed to deal with the lack of impedance and power information in ADNs. Specifically, sub-networks with unknown impedance and power information are transformed to simplified networks with known equivalent parameters that are derived from the measurements of DPMUs at the sub-network boundaries. After that, a fully distributed control strategy utilizing a multiple agent system (MAS) is employed to control voltage during voltage excursions in ADNs, and to optimize network losses if no voltage excursions occur. MAS achieves global voltage control through distributed decision-making according to the voltage-power sensitivities that are calculated by each agent based on local and neighbourhood measurements. MAS balances reactive power locally to reduce network active power losses. The convergence of the proposed distributed voltage control method is proved. Finally, the feasibility and effectiveness of the proposed method has been demonstrated on a modified IEEE 33-bus system. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The real-time simulation framework for active distribution networks was built. • A multirate simulation method was proposed with high-accuracy and stability. • The detailed hardware design of the real-time simulator was presented. Abstract Real-time simulation of large-scale active distribution networks exhibiting a wide range of time-scales puts forward higher requirements for simulation accuracy and efficiency. This paper presents an extendable method and design for the real-time simulation of active distribution networks utilising high-performance hardware field programmable gate arrays. In the aspect of numerical algorithm, a high-accuracy and stable multirate simulation algorithm is proposed. The entire active distribution network is decoupled into different subsystems by their inherent time-scales and distinct time steps are used to solve the subsystems. Then root-matching method is adopted to form the exponential difference equations that represent the behaviours of the electric distribution network being modelled, which eliminates the truncation errors and thus provides a highly accurate time-domain solution. To handle the interface between the subsystems, a multirate interfacing method is proposed. The hardware design of the multirate interfaces is presented as well. With the multirate algorithm, a fully functional extendable real-time simulator based on field programmable gate arrays is designed and implemented. Two modified IEEE 33-node systems with photovoltaics and energy storage are simulated on the 4-field-programmable-gate-arrays-based real-time simulator. Simulation results are compared with the commercial simulation tool PSCAD/EMTDC to validate the correctness and effectiveness of the proposed method and design. [ABSTRACT FROM AUTHOR]

Highlights • A centralized parameter tuning model of local control curves was proposed for DGs. • The potential benefits of DG inverters were explored to realize voltage control. • A mixed-integer second-order cone programming (MISOCP) model was formulated. Abstract The increasing penetration of distributed generators (DGs) exacerbates the risk of voltage violations in active distribution networks (ADNs). The var capacity provided by DG inverters is a potential solution for voltage regulation. The conventional centralized control strategies limited by computation and communication burdens are difficult to meet the requirement of rapid voltage control. However, the local control strategies based on real-time measurements have a fast response to the frequent fluctuations of DG outputs. The performance of these local controllers depends on the tuning of the control parameters. This paper proposes a centralized-based method to determine the local voltage control strategies for DGs. A centralized parameter tuning model of control curves is built, in which Q - V and P curt - V curves of DG inverters are mathematically formulated based on piecewise linearization. The original mixed-integer nonlinear programming (MINLP) model is converted into an effectively solved mixed-integer second-order cone programming (MISOCP) model using convex relaxation. The potential benefits of DG inverters are explored to regulate both reactive and curtailed active power, based on local voltage measurements. Case studies on a modified PG&E 69-node distribution system are carried out to verify the effectiveness of the proposed method. Results show that power losses of ADNs are significantly reduced and voltage profiles are also improved. [ABSTRACT FROM AUTHOR]

There is an increasing awareness of resilience for active distribution networks (ADNs) as extreme fault conditions pose threats to the reliable operation of power supply. Islanding operation of ADNs with distributed generators (DGs) and energy storage system (ESS) can significantly serve the critical electricity demands and improve the power supply reliability. Considering the characteristics of DG, ESS and load, a time-series islanding partition model of ADNs is established based on soft open point (SOP). The proposed model exploits the benefits of operational flexibility provided by SOP to improve the level of load recovery. It further takes into account the coordination of the control strategies among regulation devices as well as the failure duration in island partition, while satisfying a variety of operational constraints. Specifically, a mixed-integer nonlinear programming (MINLP) is employed to solve the proposed model effectively. Finally, case studies on IEEE 33-node and IEEE 123-node test feeders verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

With the integration of high shares of distributed generators (DGs), both volatile DGs and demand-side resources make it increasingly difficult to cope with the various uncertainties and put forward a higher requirement for the operational flexibility in active distribution networks (ADNs). The highly integrated distribution-level power electronic devices represented by soft open point (SOP) significantly benefit the operation of ADNs. Due to the accurate and rapid power flow control provided by SOP, various flexible resources can be coordinated in the spatial and temporal aspects, which effectively increases the DG penetration of ADNs. In this paper, the multi-dimensional characteristics of distribution system flexibility are analysed and the maximum DG hosting capacity is adopted as the index to evaluate the flexibility brought by SOP. The flexibility evaluation model is further proposed to quantify the benefits of SOP-based flexible resources, such as conventional SOP, multi-terminal SOP and SOP with energy storage. Then, the original non-convex nonlinear model is converted into an effectively solved second-order cone programming (SOCP) model using convex relaxation. To tighten the deviation of convex relaxation to the predefined accuracy, a difference-of-convex programming (DCP)-based approach is developed to solve the proposed model. Finally, case studies are performed on the modified IEEE 33-node system to verify the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

With the increasing penetration of renewables, microgrid integration has been considered as one of the most promising approaches to enhance the utilizations of various types of energy resources in smart distribution systems. In the near future, with the higher levels of intermittent renewables are envisaged, the distribution network operators will face significant challenges to the control and operation of distribution networks dispersedly. Consequently, the development of effective and motivating ancillary service schemes in a decentralized way for executing real-time control and reducing calculation and communication burden is still in its infancy and needs to be researched. To address this issue, this paper explores an optimal voltage regulation method with the participants of multi-microgrids based on multiple agent systems. Without an arbitration agent, peer agents in the multiple agent system calculate voltage sensitivities by local and neighbourhood measurements only. In this paper, a bi-level game model is proposed for voltage control process. In the upper-level, the distribution network operator searches the reasonable incentive mechanism based on the Stackelberg game. In the lower-level, microgrids make voltage control strategies autonomously based on a static game among microgrids. In the proposed method, microgrids participate in voltage control in distribution networks as ancillary service providers while maximizing their own profits. Meanwhile, the distribution network operator reduces the infrastructure reinforcement and avoids unnecessary renewable energy curtailment. Finally, the feasibility and effectiveness of the proposed method has been demonstrated on a modified IEEE 33-bus system. [ABSTRACT FROM AUTHOR]

The integration of distributed generators (DGs) exacerbates the feeder power flow fluctuation and load unbalanced condition in active distribution networks (ADNs). The unbalanced feeder load causes inefficient use of network assets and network congestion during system operation. The flexible interconnection based on the multi-terminal soft open point (SOP) significantly benefits the operation of ADNs. The multi-terminal SOP, which is a controllable power electronic device installed to replace the normally open point, provides accurate active and reactive power flow control to enable the flexible connection of feeders. An enhanced SOCP-based method for feeder load balancing using the multi-terminal SOP is proposed in this paper. By regulating the operation of the multi-terminal SOP, the proposed method can mitigate the unbalanced condition of feeder load and simultaneously reduce the power losses of ADNs. Then, the original non-convex model is converted into a second-order cone programming (SOCP) model using convex relaxation. To tighten the SOCP relaxation and improve the computation efficiency, an enhanced SOCP-based approach is developed to solve the proposed model. Finally, case studies are performed on the modified IEEE 33-node system to verify the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Soft open points (SOPs) are power electronic devices installed to replace normally open points in active electrical distribution systems. SOPs can provide active/reactive power flow control and voltage regulation under normal operating conditions as well as fast fault isolation and supply restoration under abnormal conditions. The application of SOPs can improve the controllability of distribution systems, thus further enhances the economy, flexibility and reliability of the grid. In this paper, considering the long-term operation characteristics of distributed generation, a mixed integer non-linear optimization problem is formulated to optimally determine the siting and sizing of SOPs based on the typical operation scenarios generated by Wasserstein distance. It is then transformed to and solved as a mixed integer second-order programming model. Finally, case studies on the IEEE 33-node system and Taiwan Power Company distribution system are used to verify the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

A novel two-level scheduling method was proposed in this paper, which helps an aggregator optimally schedule its flexible thermostatically controlled loads with renewable energy to arbitrage in the intraday electricity market. The proposed method maximizes the economic benefits of all the prosumers in the aggregation, and naturally helps balance intra-hour differences between supply and demand of the bulk power systems because the prices of the intraday electricity market reflects the need of the bulk power systems. In the proposed two-level scheduling, the upper level is a model predictive control optimization, of which the objective function is to minimize the sum of energy and capacity cost of imbalances and the constraints are thermal constraints based on a proposed energy-balanced model, while the lower level adopts the typical temperature priority list (TPL) control. Simulation results verified the validity of the proposed method and evaluated the effects of important influencing factors. In the base case, 41.64% imbalance cost was saved compared to the reference TPL-based control. Moreover, three further conclusions were drawn: (a) the proposed method mainly saves the imbalance cost by reducing imbalance peak, thus being suitable for places with high capacity price for imbalances; (b) parameter heterogeneity affects the performance of the proposed method, and average value method performs well only with low heterogeneity; (c) the performance of the proposed method worsens with the increase of forecast uncertainty, but keeps better than that of typical TPL-based control unless the forecast uncertainty gets very strong. [ABSTRACT FROM AUTHOR]

A large body of evidence suggests that there were extensive coastal mountains along the East Asian margin during the Late Cretaceous. However, current knowledge of the paleo-mountains — the period, range, and elevation — is limited. Therefore, direct paleoaltimetry is needed to validate and evaluate the paleo-mountains in East Asia. Our study area is Jiaolai Basin, which is located at the East Asian continental margin. We estimate the paleoelevation of Jiaolai Basin during the Late Cretaceous using carbonate clumped isotope paleothermometry. After correcting for seasonal preference, latitudinal difference, and secular climate change, we conclude that the paleoelevation of Jiaolai Basin was almost certainly ≥2.0 km at ∼80 Ma. Combined with the evidence from stratigraphy, paleogeography, and paleoclimatology, our results suggest that the existence of coastal mountains along East Asia during the Late Cretaceous is likely and the model of Okhotomorsk–East Asia collision is preferred. [ABSTRACT FROM AUTHOR]

Several flow zones exist in an ironmaking blast furnace, including the plug flow zone at the upper part, a stagnant zone in the central bottom and a funnel flow zone near the outlet. The prediction of the stagnant zone has remained a difficulty for years, and various approaches have been attempted in the past. In this article, a new approach based on novel potential flow model was employed to predict the profile of the stagnant zone and the plug flow and funnel flow zones. The results were verified by the experimental observations in literature. The effect of the material flow resistance in the model on the stagnant and flowing zones was investigated, and the results were also compared with the traditional potential flow model. It is demonstrated that the novel potential flow model has the advantage in predicting the stagnant and flowing zones simultaneously without a need to implement extra complicated correlations. [Display omitted] • An approach to numerically predict deadman in blast furnace is proposed. • Deadman changes with ratio of potential flow and piping flow resistances. • Predicted results accord fairly well with reality. • Material resistance surely exists within deadman in blast furnace. [ABSTRACT FROM AUTHOR]

This paper proposes a robust scheduling strategy to manage a building energy system with solar power generation system, multi-chiller system and ice thermal energy storage under prediction uncertainty. The strategy employs a two-stage adjustable robust formulation to minimize the system operation cost, wherein a parameter is introduced to adjust the level of conservatism of the robust solution against the modeled uncertainty. Then a column and constraint generation algorithm with modified initialization strategy is adopted to solve this optimization model along with mixed-integer linear programming. Further, we evaluate the performance of the proposed strategy by hourly simulating the system operation of a practical project with Monte Carlo simulation. Numerical results show that the robust scheduling with a proper parameter can be superior to the deterministic strategy in all the studied cases. Additionally, the proposed strategy has similar results with the model-based predictive control strategy while the former only needs to be implemented once. Even in the highest load case, the relative deviation between the two strategies is less than 2%. [ABSTRACT FROM AUTHOR]

An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT_Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. [ABSTRACT FROM AUTHOR]

In deep time, climates are mainly classified by climatically sensitive deposits, paleontological evidences, and modeling. However, they only have limited applicability in deep time studies. Here, we propose a new paleoclimate classification based on the widely used Köppen climate classification. The proposed new classification is simple and quantitative, but bridges the gap between modern and deep time climate studies. The new classification is closely related to but differs from that of Köppen by changing some limits. A world map using the new classification shows the same patterns as the world map of the Köppen climate classification. Using the new classification, we are able to solve a long-standing problem about the climates of East Asia during the Eocene. We found that East Asia shared the same climate type (Ca: Subtropical) at all studied locations, supporting the hypothesis of monsoon or monsoon-like climate that prevailed there during the Eocene. [ABSTRACT FROM AUTHOR]

In this paper, a robust approach is developed to tackle the uncertainty of PV power output for load scheduling of smart homes integrated with household PV system. Specifically, a robust formulation is proposed and further transformed to an equivalent quadratic programming problem. Day-ahead load schedules with different robustness can be generated by solving the proposed robust formulation with different predefined parameters. The validity and advantage of the proposed approach has been verified by simulation results. Also, the effects of feed-in tariff and PV output have been evaluated. [ABSTRACT FROM AUTHOR]

The Tertiary lacustrine Niubao Formation is well exposed in the middle-western part of the Lunpola Basin, central Tibetan Plateau, where crude oil was once discovered during drilling campaigns. Sedimentological, organic petrographic and geochemical work was performed on the upper and middle members of this formation in order to investigate its hydrocarbon source rock potential. Sedimentological analyses indicate that both members were deposited in relatively deep lake conditions away from the influence of big stream system, with the upper Niubao Formation (UNF) having higher sand content. The two members contain abundant high-quality Type I kerogen derived mainly from plankton, algae, and bacteria. Compared with samples of the middle Niubao Formation (MNF), UNF samples also contain more Type II and Type III kerogens of terrestrial origin. Biomarkers of source rock extracts suggest that a long-standing anoxic, stratified, and saline ancient lake occupid the basin during deposition of the two members, which was conducive to the preservation of organic matter. However, higher gammacerane content and the presence of β-carotane in MNF samples imply a more saline lake condition. Rock-Eval T max and biomarker parameters reveal marginal maturity and immaturity for samples from MNF and UNF, respectively. Therefore, MNF has better source rocks of higher maturity might be the main hydrocarbon generating member of the basin; similar diagnostic biomarkers and biomarker parameters reported in the crude oil also imply its affiliation with the source rocks of MNF. [ABSTRACT FROM AUTHOR]

The Namling–Oiyug basin is the only Cenozoic lake basin that has hydrocarbon potential in southern Tibet, China. Coal was once exploited in the basin from the early Miocene Mangxiang Formation, which also hosts oil-prone source rock layers. Herein, a combined investigation of sedimentological features and organic geochemistry is performed on a measured outcrop section of the Mangxiang Formation to study the lake-basin types as well as the depositional history of aquatic and terrestrial organic matter (OM). There are two periods in the lake basin evolution history: the balanced-fill and overfilled stages. In the balanced-fill basin stage, oil-prone laminated shale was deposited in a relatively deep lake environment, with total organic carbon (TOC) contents around 5 wt.%, and HI values up to 316 mg HC/g TOC, indicating hydrogen-poor Type II kerogen with transition to Type III kerogen. Comparison between maceral composition and geochemical properties suggests that the relative low HI values are results of thermal maturity. The high value of the gammacerane index indicates water stratification of the lake. In this stage, water and sediment input approximately equaled potential accommodation, the lake was relatively stable and hosted large amounts of lacustrine algae, and accumulated OM with low terrestrial input in an anoxic environment. After the onset of the thrusting, the potential accommodation was decreased, large volumes of clastic sediments also drained into the lake from the surrounding area, resulting in an overfilled lake basin. During this stage, peat was deposited in freshwater environment, with > 30 wt.% TOC, low HI, and Type III OM. The high Pr/Ph (> 3) implies oxic conditions. [ABSTRACT FROM AUTHOR]

This paper proposes an accurate dense output formula for exponential integrators. The computation of matrix exponential function is a vital step in implementing exponential integrators. By scrutinizing the computational process of matrix exponentials using the scaling and squaring method, valuable intermediate results in this process are identified and then used to establish a dense output formula. Efficient computation of dense outputs by the proposed formula enables time integration methods to set their simulation step sizes more flexibly. The efficacy of the proposed formula is verified through numerical examples from the power engineering field. [ABSTRACT FROM AUTHOR]

Long-standing problems in the geological evolution of the Tibetan–Himalayan orogen include where the India–Asia convergence was accommodated and how the plateau grew. To clarify these problems, we review the deformations and their role in the plateau's growth. Our results show that ~ 1630 km of shortening occurred across the Tibetan–Himalayan orogen since ~ 55 Ma, with more than ~ 1400 km accommodated by large-scale thrust belts. These thrust belts display an outward expansion from central Tibet and couple with the surficial uplift. The development of the Tibetan plateau involved three significant steps: Primitive plateau (~ 90–55 Ma), Proto-plateau (~ 55–40 Ma), and Neoteric plateau (~ 40–0 Ma). Several processes have collaborated to produce the Proto-plateau, including the pre-existing Primitive plateau, the India–Asia collision, and subductions of Greater India and Songpan–Ganzi beneath the Lhasa–Qiangtang terrane. Since ~ 40 Ma, the Proto-plateau, which was dominated by a topographic gradient, lower crustal flow and continuous India–Asia convergence, experienced three periods of rapid outward growth (~ 40–23, ~ 23–10, and ~ 10–0 Ma) in general. The N–S trending rifts were caused by the eastward growth of the plateau dominated by thrusting and crust flow in central Tibet, while they were the results of intense N–S shortening in Himalaya. [ABSTRACT FROM AUTHOR]

The history of volcanic activity of the Gangdese arc in southern Tibet during the Cretaceous remains poorly known due to the intense erosion of the arc. Here we present zircon U–Pb ages, trace element and Hf isotopic data of tuffs and volcanic conglomerates from the Chongdoi and the Ngamring Formation in the Xigaze forearc basin. Three tuff samples from the Chongdoi Formation yield zircon U–Pb ages around 112 Ma. Such ages could be taken as their depositional ages, indicating that detrital clasts of the Chongdoi Formation were deposited at that time. One andesitic conglomerate sample from the Ngamring Formation was dated at ca. 105 Ma, the other rhyolitic conglomerate sample and one tuff sample were dated to be ca. 95 Ma and 91 Ma, respectively, suggesting that this formation was formed during the late Albian–late Turonian. All zircons illustrate I-type granitoid characteristics and possess low Ti-in-zircon temperatures (< 800 °C). Zircon ε Hf (t) values of tuffs from the Chongdoi Formation define two groups: (1) the first group of 117–110 Ma displays large positive ε Hf (t) values (+ 12.1 to + 17.1), larger than those of the tuff from the Ngamring Formation (+ 6.0 to + 10.2); (2) the second group of 119–111 Ma yields negative to small positive ε Hf (t) values (− 4.5 to + 1.1). All above observations indicate that their host rocks were derived from the juvenile materials with significant input of fluids. Combined with extant data, the first group and the tuff, volcanic conglomerates from the Ngamring Formation are mostly likely derived from the eroded Cretaceous volcanic rocks in the Gangdese arc, while the second group is likely sourced from the late Early Cretaceous volcanic rocks in the central Lhasa terrane. Our data confirm the presence of Cretaceous volcanism in the Gangdese arc, suggesting that the Neo-Tethyan Ocean lithosphere was most likely subducted northerly in a normal angle rather than in a manner of low-angle subduction. [ABSTRACT FROM AUTHOR]

Abstract: The surface uplift history of the Tibetan Plateau (TP) offers a key testing ground for evaluating models of collisional tectonics and holds important implications for processes ranging from global cooling to the onset of the Asian monsoon. Various models have been proposed to reveal the surface uplift history of the TP, but controversies remain. We evaluate these models using data from sedimentology and stratigraphy, structural geology, magmatism, exhumation, and paleoaltimetry studies. Structural analyses indicate that thrust belts, which spread from the central TP outward toward its surrounding margins, accommodated most of the India–Asia convergence, and facilitated crustal shortening and thickening in the central TP. Eocene adakitic rocks located in the Qiangtang and the Lhasa blocks likely were generated by partial melting of an eclogitic source. Paleogene (50–30Ma) potassic rocks only occur in the Qiangtang block, whereas Late Oligocene–Late Miocene (26–8Ma) potassic rocks occur both in the Qiangtang and Lhasa blocks. Low-temperature thermochronologic ages in the central TP are older than 40–35Ma, whereas those in the margins are younger than 20Ma (mostly Late Miocene, and Pliocene/Pleistocene in age). Independent paleoaltimetry estimates suggest that the Lhasa and Qiangtang terranes attained their current elevations during the Eocene, most likely due to the initial collision between India and Lhasa, whereas the Hoh Xil basin area to the north and Himalayas to the south were still low, even below sea level in the latter case. We argue for an inside-out growth pattern for the Tibetan Plateau. The TP grew southward and northward from a nucleus of high topography and is likely to continue expanding along the Mazar Tagh fault to the northwest, the Kuantai Shan-Hei Shan-Longshou Shan to the northeast, the Longquan Shan to the east and the Shillong plateau to the south if the northward force of India would not diminished. [Copyright &y& Elsevier]

Abstract: Cretaceous climate data of the long-lived Cretaceous Songliao Basin (SB) in eastern Asia is correlated and compared with the Western Interior Seaway (WIS) on the northern American plate, in order to understand better the dynamics of the Earth's past ‘greenhouse’ climates. Nearly continuous Late Cretaceous terrestrial deposition in the Songliao Basin is represented by two cores totaling 2431m in length. The Turonian–Maastrichtian age of the section is based on integrated stratigraphy, and is comparable in age with Upper Cretaceous strata in the WIS. Being consistent with global trends, the dynamic Late Cretaceous climates of both the SB and WIS gradually cooled from the warmest Albian–Cenomanian time to the end of the Maastrichtian with several intervening warm periods as did the global climate. However regional differences existed, the Songliao Basin climate was humid to semi-humid, warm temperate–subtropical and the Western Interior Seaway was in the humid, warm temperate zone and experienced only moderate climatic changes. The shifts of oxygen isotope data in the Songliao Basin were frequent and abrupt, whereas WIS records more gradual change affected mainly by fresh-water runoff mixing with southern Tethyan and northern Arctic waters. Sedimentary cycles of eccentricity, obliquity and precession bands are recorded in both the SB and WIS basins. The sedimentary cycles in the WIS and SB are interpreted to be related to variations of the wet/dry runoff cycles, which indicate that orbital forcing played an important role in global climate change in Late Cretaceous. The most favorable condition for organic carbon burial in both the SB and WIS basin was bottom water anoxia regardless of the cause of the anoxia. But the organic carbon burial rate was usually much higher in the Songliao Lake than in the WI epeiric sea suggesting that giant lakes may serve as important sinks of atmospheric CO2. In both basins organic-rich deposits formed during a rise in water level and incursion of saline waters. The integration of paleoclimate data from Cretaceous marine deposits and terrestrial sedimentary record will promote our understanding of the Cretaceous ‘greenhouse’ climate change and may provide insights for a future greenhouse world. [Copyright &y& Elsevier]

Abstract: Clay mineralogy of a 60m thick section of the middle Mingshui Formation (upper Campanian to lower Maastrichtian) from the SKIn borehole (Songliao Basin in NE China) has been studied to assess the palaeoclimate and provenance. The sedimentary succession is composed of shore to shallow lacustrine mudstones and siltstones in the lower part, and meandering fluvial sandstone–mudstone sequences in the upper part. The clay mineral assemblage is characterized by the predominance of smectitic minerals, with some exceptions of illite-rich layers, and trace amounts of kaolinite and chlorite. The high smectite content (>90% on average) in lacustrine sediments could source from erosion of smetitic soils and volcanic materials in source areas. The Lesser Xing'an–Zhangguangcai Range was the potential provenance area for the sediments, with volcanic activity occurring at ~70Ma, when the temperate semi-humid palaeoclimate was favorable for the clay formation. Smectite presented in meandering fluvial sandstones is of early diagenetic origin, formed by hydrolysis and alteration of primary minerals after deposition. Illite in overbank deposits is interpreted as a result of erosion of granitic rocks and sorting in sedimentation processes. The clay mineralogy of the studied strata contains information on palaeoclimate and provenance, although early diagenetic processes may have influenced the mineralogical composition in some intervals of sandstones. [Copyright &y& Elsevier]

Abstract: In order to define the provenance change across the nonconformable boundary between the second and the third members of the Upper Cretaceous Nenjiang Formation (Campanian) in the north-central area of the Songliao Basin, two sandstone samples above (sample a-1 from the fourth member of the Nenjiang) and below (sample z-1 from the first member of the Yaojia Formation) the nonconformity were collected from core holes. U–Pb dating was performed on detrital zircons separated from the three sandstone samples. Detrital zircons from sample a-1 have dominant age populations of 100–110Ma, 190–220Ma, and ~1800Ma, and sample z-1 has dominant ages of 130–150Ma and ~350Ma. This paper demonstrates that the provenance of the fourth member of the Nenjiang Formation is significantly different from the first member of the Coniacian Yaojia Formation. The provenance above the nonconformity became much more complex and the eastern source increased significantly, while the western source sharply declined. The main source areas of the fourth member of the Nenjiang Formation are mainly the Zhangguangcai Range, the eastern Lesser Xiang'an Range and the southeast of Songliao Basin. The dominant provenance of the first member of the Yaojia Formation is the northern, the central and the southern Great Xing'an Range. According to the depositional ages and combining the latest seismic stratigraphic profiles in the Songliao Basin, the tectonic inversion of the eastern Songliao Basin began between 73Ma and 87Ma, which differs from the previous age of 73Ma. [Copyright &y& Elsevier]

Abstract: As a paradigm of greenhouse climate in Earth's history, the Cretaceous provides significant rock records of global climate changes under conditions of greenhouse climate. The Songliao Basin, among the longest duration (85–90m.y.) of continental sedimentary basins, provides an excellent opportunity to recover a nearly complete Cretaceous terrestrial sedimentary record. Extensive lake deposits, ten-kilometers deep and covering an area of 260,000km2 of the Songliao Basin, provide unique, detailed records that can be tied to the global stratigraphic time scale, thereby improving our understanding of the continental paleoclimate and ecological system. The two coreholes at SKIs and SKIn sites were drilled into this basin and completed with a total length of 2485.89m of recovered core that spanned the complete middle-to-Upper Cretaceous strata in the basin. The unique geological setting of long-term continuous subsidence within the largest Cretaceous landmass in the world — makes the Cretaceous Songliao Basin of northeastern China an ideal place to study Cretaceous climate change on the continent. This paper reviews the literature on the paleogeography and paleoclimate of the northern East Asia and the Songliao Basin during the Cretaceous. Based on the climatologically sensitive deposits, oxygen isotope studies, and paleontology, the climate during the Cretaceous in the Songliao Basin was temperate and humid with relatively abundant rainfall. During the period, significant changes – four cooling, three warming, and three semiarid events – are generally consistent with the oxygen isotope data from East Asia, and the four cooling events, in Berriasian–Valanginian, Aptian–Albian, early Santonian, and Campanian–Maastrichtian, may be related to potential glaciations in Cretaceous. [Copyright &y& Elsevier]

Abstract: The Continental Scientific Drilling Project at the Cretaceous-age Songliao Basin is a drilling initiative under the framework of the International Continental Scientific Drilling Program, to recover a nearly complete Cretaceous terrestrial sedimentary record in the Songliao Basin, northeastern China. The recovered cores will provide unique opportunities for the geosciences community to advance the understanding of climate change in the Cretaceous greenhouse world, and provide a documentation of geological events relevant to the carbon cycle during this time period. This drilling project will address significant geological questions, such as the identification of important stratigraphic boundaries and the marine-terrestrial correlations of stratigraphy, the reasons for the biotic response to the terrestrial environmental changes, the terrestrial response to the Cretaceous oceanic anoxic events, the formation of terrestrial petroleum source rocks, and the mechanisms for the Cretaceous magnetic Normal Superchron (CNS). In the first stage of this drilling project, the SKI drilling, rock cores of 2485.89m in total length were recovered and the recovery ratio reached 96.46%. A series of drilling and coring technologies including regular, confined, directional, and sealed coring, were utilized to ensure a higher recovery ratio for the core, and will be described at the end of this paper. Well loggings were conducted right after coring. Core handling and storage were arranged in such a way that the scientific research was conducted on half of each core, whereas the other half of each core was preserved for long-term storage. The upcoming second stage, the SKII drilling, will combine with data from the existing SKI to provide complete high-resolution climate records of the terrestrial environment for the whole Cretaceous time period. [Copyright &y& Elsevier]

Abstract: The Cretaceous Xigaze ophiolite is best exposed at the central Yarlung Zangbo Suture Zone (YZSZ, Tibet) which also includes the Gangdese arc and the Xigaze forearc basin. This study reports new geochronological and geochemical data for this ophiolite to revisit its geodynamic and petrogenetic evolution. The Xigaze peridotites have low CaO and Al2O3 contents and U-shaped Rare Earth Element (REE) patterns, suggesting that they are residues after moderate to high degrees of partial melting and were modified by infiltration of Light Rare Earth Element (LREE)-enriched boninitic melts. The Xigaze crustal rocks belong to two groups: Mid-Ocean Ridge Basalt (MORB)-like rocks and boninitic rocks showing a uniform LREE depletion and flat to LREE enrichment on chondrite-normalized patterns, respectively. Geochemically, both groups show the influence of subducting oceanic slab-derived fluids. LA-ICPMS zircon U–Pb and Lu–Hf analyses from dolerite and quartz diorite dikes, which intruded into the mantle peridotite, and dolerite sheeted sills show that they were generated between 127 and 124Ma. The zircons possess positive εHf(t) values ranging from +7.5 to +17.3. Taking into account the geological and geochronological characteristics of the central-western YZSZ, we propose that ophiolites in this region formed in a forearc spreading setting through rapid slab rollback during subduction initiation between 130 and 120Ma. Following this stage of spreading, the forearc was stabilized and the zone of melting migrated beneath the Gangdese arc producing the voluminous Late Cretaceous granitoids displaying depleted mantle-type Hf isotopic compositions. Our model provides a new explanation for the generation and evolution of forearc-type ophiolites. [Copyright &y& Elsevier]

Abstract: To understand the magmatic and tectonic events in the Eastern Kunlun Range, we conducted systematic zircon U–Pb geochronology, and paired zircon (ZHe) and apatite (AHe) (U–Th)/He themchronology investigations in the central and eastern segments of this range. Zircon U–Pb ages show two-stage magmatic events of Late Silurian and latest Permian–Early Jurassic. ZHe and AHe ages and multi-system thermochronometers reveal multi-stage rapid cooling events. From a combination of these data with previously published geochronological and thermochronological ages, and regional geological setting, we confirm several important Phanerozoic tectono-magmatic events in this region. Whereas the Silurian granites might be related to a small paleo-ocean subduction and subsequent collision, the latest Permian–Early Triassic granitoids were produced by northward subduction of the Songpan–Ganzi Paleo-Tethyan ocean. The Late Triassic–earliest Jurassic granitoids and Late Triassic–Early Jurassic exhumation are interpreted as response to the collision between Kunlun–Qaidam and Qiangtang. Samples close to the Kunlun Fault show rapid Late Oligocene–Early Miocene exhumation (1.3–1.6km/Ma), whereas those from the northern part of central segment display extremely low exhumation rates (0.02–0.05km/Ma). This heterogeneous denudation during 30–20Ma between northern and southern part of the central segment requires that crustal thickening was completed by lower-crustal underthrusting with little exhumation or crustal thickening in pre-Cenozoic times. The activity of the Kunlun Fault and associated normal faulting component were probably responsible for this stage of rapid exhumation in the southern part. The complex tectono-magmatic evolution of the Eastern Kunlun Range is controlled by pre-Cenozoic paleo-ocean subductions and subsequent continent collisions and Paleogene India–Asia collision. [Copyright &y& Elsevier]

Abstract: With the various detail pricing schemes designed by utilities and the development of the smart grid technologies, consumers are motivated and enabled to schedule their home appliances to save energy, reduce cost and help grid operation. This paper presents a novel Traversal-and-Pruning (TP) algorithm which schedules thermostatically controlled household loads to meet an optimization objective considering both payment and comfort settings. The novel TP algorithm is robust and a flexible method is developed to balance the optimality and speed of the algorithm. Simulation results show that an improved load schedule is obtained by the novel TP algorithm compared to an existing algorithm. [Copyright &y& Elsevier]

Highlights: [•] We analysed the biomarker and hydrocarbon potential of samples in the Lunpola Basin. [•] Quantity, quality and maturity of organic matter were determined. [•] The study indicated that paleoclimate during sample deposition was probably cool and arid. [ABSTRACT FROM AUTHOR]

Abstract: The northern dimension of Greater India, defined as the continental part of India from which the Himalayan fold–thrust belt was derived, is difficult to determine due to major tectonic deformations of the Himalaya during the Tertiary caused by the India–Eurasian collision. Paleomagnetic data from the Tethyan Himalaya can potentially help determine this dimension. However, the tectonic deformations also led to widespread remagnetization of rocks there and thus previously published paleomagnetic poles from the lower Mesozoic Himalayan rocks may not accurately reflect their original paleomagnetic directions. To better understand the Triassic history of India in a Gondwana configuration, we report new paleomagnetic data (after tilt correction D =345.5°, I =−43.0°, α95 =12.0°, k =17.3, N =10 sites and the corresponding paleopole at 34.5°N, 282.2°E with A95 =11.7°) of Triassic limestone and sandstone from the Tulong Group in the Tethyan Himalaya. The primary features of the magnetization are supported by the positive fold test. Our new Triassic paleomagnetic pole overlaps with 230–250Ma poles from India, suggesting the close affinity between the Tethyan Himalaya and cratonic India since the Triassic. Assuming that the Tethyan Himalaya was a part of the Great India since Triassic, the differences between the Tethyan Himalaya paleolatitude obtained by this study and those previously reported for the cratonic India imply ∼1300km dimension of the Tethyan Himalaya has been absorbed after the Eurasia–India collision. [Copyright &y& Elsevier]

Abstract: Despite more than 30 years’ studies in the Yarlung Zangbo Suture Zone (YZSZ), southern Tibet is still a region of discovery and the geological evolution of the Neo-Tethys here remains controversial. In this paper we present the new field observation, petrography, zircon U–Pb dating and geochemistry of the Zhongba mafic rocks in the western segment of the YZSZ. Zircon U–Pb analyses from a diabase using SIMS (Secondary Ion Mass Spectrometry) yielded a concordant age of 125.7±0.9Ma. All the Zhongba mafic rocks exhibit LREE enrichment (LaN/YbN =4.7–15.8) without Eu anomalies (δEu=0.97–1.01). Their Primitive-Mantle-normalized trace element patterns are similar to those of the average OIB and Hawaii alkaline basalts, as well as other OIB-type rocks already reported in the central-western YZSZ. These observations lead us to suggest the existence of a series of seamounts within the Neo-Tethys during the Early Cretaceous. These OIB-type rocks could be originated from (1) hotspot mantle; (2) near-ridge seamounts by melting-induced mixing of two distinct mantle sources; (3) late-stage magmatism fed by melts that originated from an asthenospheric window due to slab delamination. Combining literature data from the entire YZSZ, which include studies of the MORB- and IAB-type rocks and mantle peridotites, we prefer the third explanation that the OIB-type rocks represent a late-stage magmatic activity above an intra-oceanic supra-subduction zone within the Neo-Tethys. [Copyright &y& Elsevier]

Abstract: Understanding why continental deformation departs from the theory of plate tectonics requires a detailed knowledge of three-dimensional structures at a lithospheric scale. In Tibet, the end-member models of continental deformation make distinctively different predictions on strain distribution and contrasting structural geometry as a function of depth. Specifically, the thin-viscous-sheet model predicts vertically coherent deformation while channel-flow and continental-subduction models predict the presence of sub-horizontal detachment zones within or at the base of the Tibetan crust during the Cenozoic deformation. To differentiate the above models, we conducted a high-resolution seismic-reflection survey across the active left-slip Kunlun fault and its nearby contractional structures. The results of this work show that the actively deforming middle Tibetan crust is dominated by discrete sub-horizontal simple-shear zones that terminate the sub-vertical, left-slip Kunlun fault above and mantle-cutting thrusts below. The flat shear zones appear to act as roof and floor thrusts of large duplex structures that transfer shortening strain from locally deformed and coupled lower crust and mantle lithosphere below to the high-strain domains of the upper crust above. The middle-crustal strain-transfer model proposed here implies that the weak Tibetan middle crust may not be active everywhere during the Indo-Asian collision. It also predicts that the kinematics of the activated portions of the middle crust, whether being deformed by simple shear or channel-flow deformation, may vary from place to place, depending strongly on the lateral variation of mechanical strength at different depths of the lithosphere. Our approach of establishing the kinematics of middle-crust deformation departs significantly from the early work that emphasizes exclusively the role of vertically varying rheology in controlling the mode of continental deformation. [Copyright &y& Elsevier]

Abstract: The Zhuonai Lake and Lunpori oil shale, located in the central Tibetan Plateau, were deposited in a Tertiary lacustrine environment in the Hoh Xil and Lunpola Basins, respectively. A combined investigation of sedimentary, organic geochemistry, and organic carbon isotope was performed to define source rock potential, the palaeoenvironment, and source of the organic matter. Three types of facies sequences are developed in the Zhuonai Lake section and oil shale mainly occurs in the oil shale-marl sequence. The oil shale-silty claystone and oil shale-marl facies sequences are developed in the Lunpori section. Both oil shales are finely stratified especially for the Lunpori oil shale with thickness of the laminae about 10μm which contains abundant pyrite crystals and fossilized fish bones. Both the Zhuonai Lake and Lunpori oil shale contain high values of total organic matter (TOC), S2, and hydrogen index (HI), indicating the oil shales have good oil source rock potential. Tmax values show an immature stage of organic matter for the Zhuonai Lake oil shale and thermally marginally mature for the Lunpori oil shale because of difference in their burial history. Lunpori oil shale shows the characteristics of amorphous organic matter (AOM) dominance, odd-over-even predominance, maximum n-alkanes peak at nC25 or nC23, higher proportion of C29 sterane, light δ13Corg values (−30.0‰ to −27.4‰), high concentrations of phytane (Pr/Ph ratio ranging from 0.02 to 0.18), high values of gammacerane index (up to 25.26), and presence of β-carotane, which are consistent with a reducing, stratified, and hypersaline palaeo-lake with main contribution of algae and bacteria to the organic matter (OM). Oil shale samples from the lower and upper part of the Zhuonai Lake section are characterized by low H/C ratios and high O/C ratios, amorphous humic OM and vitrinite dominance, odd-over-even predominance with long-chain n-alkanes dominance, heavy organic carbon isotope, and C29 >C27 sterane distribution, in agreement with a main contribution of land plant. The heavy organic carbon isotope suggests the expanding of C4 land plant during the early Miocene. While the most samples show characteristics of AOM dominance, maximum peak at nC29 or nC31, and high C27 sterane concentration, consistent with a main contribution from algae to the OM. The Pr/Ph ratio cannot be applied as a measure for redox conditions in the section because of maturity effects. Biomarker analysis indicates that the salinity during the deposition of the Zhuonai Lake oil shale was not enhanced. The Oligocene Lunpori oil shale and the Early Miocene Zhuonai Lake oil shale recorded the variation of palaeolimnological water chemistry. The development history of the palaeo-lakes from the Oligocene saline to the Early Miocene fresh water reflects the variation of palaeoclimate from dry to humid in the central Tibetan Plateau. [Copyright &y& Elsevier]

Abstract: Oceanic Anoxic Events (OAEs) represent brief periods of burial of large amounts of organic carbon in the oceans during Cretaceous time. Burial of organic carbon, which preferentially sequestered isotopically lighter carbon during OAEs, resulted in positive δ13C excursions of 2–3‰ recognizable in global ocean. These deposits are typically dark–grey to black shales, considered to be the result of interaction between extreme warm climate, ocean circulation, high bioproductivity and organic carbon preservation. Less interest has been given to periods between OAEs, when oxic deep sea deposits such as red marls and red shales were deposited during mid- and Late Cretaceous. The latter deposits are associated with very low content of organic carbon and oxic depositional environments which dominated western Tethys in post Turonian time, up to the early Eocene. Feedbacks among geochemical cycles in response to decreasing global temperatures, increasing deep ocean circulation forced by high-latitude deep water formation along the Antarctic margin, and widening and deepening of the interconnections between the oceanic basins may have been responsible for the major paleoceanographic change from deposition of organic carbon-rich black shales during mid-Cretaceous, to world-wide deposition of Cretaceous Oceanic Red Beds (CORBs) in the Late Cretaceous. The presence of CORBs sandwiched between mid-Cretaceous OAEs may reflect major climate and paleoceanographic changes. In a contrast to extremely warm climates during the OAEs, the CORBs suggest cold periods, and therefore oscillating climate shifts, that have seldom been considered during modeling of Cretaceous greenhouse climate and global carbon cycling. [Copyright &y& Elsevier]

Abstract: The Gyangze basin, located in southern Tibet, is one of the representative areas for Cretaceous Oceanic Red Beds (CORBs). We investigated and inter-correlated several new CORB outcrops in the western and southeastern part of the Gyangze area in addition to the previously described Chuangde section. The CORBs in the Gyangze basin mainly consist of shales, thin-bedded marls, re-sedimented limestones and clasts supported conglomerates-breccias. Planktonic foraminifers in the carbonate rocks within CORBs belong to the Globotruncana ventricosa and Globotruncanita calcarata zones, indicative of middle Campanian age. The facies assemblages in the different sections indicate that the depositional environments of CORBs range from outer base-of-slope apron to basin zones. Within carbonates, we observed microfacies types characteristic of basin, open deep shelf margin or toe-of-slope environments. Gravity transport resulted from the steepening of the sea floor in the Gyangze basin owing to subduction during the Campanian. Relatively oxic bottom water conditions prevailed below the toe-of-slope environment in the Gyangze basin during CORB deposition. However, the presence of gray clasts within a multicoloured matrix suggests less oxic conditions at shallower water depths within the basin. [Copyright &y& Elsevier]

Abstract: A proper evaluation on the power supply capability of urban distribution system is of much social and economical significance. In competitive marketing environment, to satisfy the sustainable growth of distribution loads, electric utilities must judge whether the return of power supply capability is sustainable and valued against the certain amount of investment. Therefore, to make up the insufficiency of traditional methods referring from the concept of total transfer capability (TTC) of transmission system, this paper proposes a straightforward method to evaluate the power supply capability (PSC) of distribution system, which is based on N −1 contingency analysis of interconnected main-transformers. Firstly, a series of interconnected main-transformer groups are drawn from the main-transformers’ interconnection analysis after the topological simplification of distribution system. Secondly, the maximum average loadability of each main-transformer is concluded through the N −1 contingency analysis of every interconnected group. Finally, based on a comprehensive analysis of all the interconnected groups’ results, the maximum permissible loadability of each main-transformer can be obtained, thus the PSC of the entire distribution system can be calculated. Through the application in a distribution system of Shanghai, China, the effectiveness and the accuracy of the method are demonstrated. The application results suggest that, the method presented in this paper is a simple and practical tool to evaluate the PSC of a distribution system, which needs only one calculation with constraints according to the N −1 guideline. Moreover, the interconnection weak-points and the interconnection bottlenecks of the distribution system can be identified easily with this approach, thus providing effective references for urban distribution network planning and the following project investment decisions. [ABSTRACT FROM AUTHOR]

Abstract: Parkinson’s disease (PD) is hallmarked by the abnormal intracellular inclusions (Lewy bodies or LBs) in dopaminergic cells. Amyloidogenic protein α-synuclein (α-syn) and iron (including both Fe(III) and Fe(II)) are both found to be present in LBs. The interaction between iron and α-syn might have important biological relevance to PD etiology. Previously, a moderate binding affinity between α-syn and Fe(II) (5.8×103 M−1) has been measured, but studies on the binding between α-syn and Fe(III) have not been reported. In this work, electrospray mass spectrometry (ES-MS), cyclic voltammetry (CV), and fluorescence spectroscopy were used to study the binding between α-syn and Fe(II) and the redox property of the resultant α-syn–Fe(II) complex. The complex is of a 1:1 stoichiometry and can be readily oxidized electrochemically and chemically (by O2) to the putative α-syn–Fe(III) complex, with H2O2 as a co-product. The reduction potential was estimated to be 0.025V vs. Ag/AgCl, which represents a shift by −0.550V vs. the standard reduction potential of the free Fe(III)/Fe(II) couple. Such a shift allows a binding constant between α-syn and Fe(III), 1.2×1013 M−1, to be deduced. Despite the relatively high binding affinity, α-syn–Fe(III) generated from the oxidation of α-syn–Fe(II) still dissociates due to the stronger tendency of Fe(III) to hydrolyze to Fe(OH)3 and/or ferrihydrite gel. The roles of α-syn and its interaction with Fe(III) and/or Fe(II) are discussed in the context of oxidative stress, metal-catalyzed α-syn aggregation, and iron transfer processes. [Copyright &y& Elsevier]

Abstract: The northeast of the Qinghai-Tibet Plateau, from the Hoh Xil Basin to the Hexi Corridor Basin, demonstrates a basin-ridge geomorphy that is the result of the long-term uplift of the Qinghai-Tibet Plateau. The geological evolution of the Qinghai-Tibet Plateau is recorded in its associated basins. From the Cenozoic sedimentary filling pattern in the Hoh Xil, Qaidam and Jiuquan Basins, we find that the evolution of these basins is similar: they began as strike-slip basins, evolved into foreland basins, and then to intermontane basins. Foreland basins are the direct result of orogenic activity in the northeast of Qinghai-Tibet Plateau, and can be documented to have formed over the following time periods: 49–23 Ma for the Hoh Xil foreland basin, 46–2.45 Ma for the Qaidam foreland basin, and 29.5–0 Ma for the Jiuquan foreland basin. This northward migration in the timing of foreland basin development suggests that the northeastern part of Tibet grew at least in part by accretion of Cenozoic sedimentary basins to its northern margin. [Copyright &y& Elsevier]

The Hoh Xil Basin is the largest Cenozoic sedimentary basin in the hinterland of the Tibetan Plateau. Tertiary sedimentary strata 5.8 km thick, comprising the Fenghuoshan, Yaxicuo and Wudaoliang groups, provide compelling evidence concerning the crustal shortening, erosion and peneplanation of the northern Tibetan Plateau. The basal Fenghuoshan and overlying Yaxicuo groups span the Eocene-Early Oligocene stratigraphically, and have been dated by magnetostratigraphy as 56–30 Ma old. Both groups are composed of terrigenous rocks. Provenance analysis of sandstones and conglomerates demonstrates that Permian and Triassic strata in the Tanggula Orogenic Zone in the south were the source for the Fenghuoshan Group. In contrast, the Carboniferous–Triassic strata in the Tanggula, Bairizhajia, and Heishishan-Gaoshan orogenic zones in the north, were the source for the Yaxicuo Group.During the Late Oligocene, northern Tibet underwent strong north–south crustal shortening (∼43%) and thickening. Extensive erosion, which occurred over the entire plateau surface near the end of the Oligocene, resulted in development of a peneplain surface. The latter is overlain by the Early Miocene Wudaoliang Group, composed of fresh water limestones. These are exposed both on summit surfaces, as well as on the valley floors, showing that a phase of differential uplift occurred after the deposition of the Wudaoliang Group. This post-Miocene differential uplift was due to regional extension, in a region of overall shortening. Even though we have not succeeded in obtaining conclusive data about the exact timing of phases of rapid uplift of the Tibetan Plateau, it is most likely that the major phase of uplift occurred during the Late Oligocene. [Copyright &y& Elsevier]

Pearl River Delta (PRD) region of South China is abundant of geothermal water resources. However, the development and utilization level of geothermal resources in this region is relatively low, due in part to the lack of fundamental geochemical research. To access water-rock interaction processes of the PRD geothermal system, we analyzed the geochemistry of geothermal waters by combining trace elements (B, Sr, and Br) and isotopes (δ11B and 87Sr/86Sr) with conventional tracers (major elements) that had been reported. The Cl/Br ratios (from 31 to 639) confirm the multi-source salinity of marine origin, precipitation, and a minor dissolution of halite. Major ions chemistry highlights the influence of ions exchange, the dissolution of carbonate, silicate, and sulphate minerals as well as the contribution of seawater. The Cl/B ratios (61 to 22,583) suggest interactions with carbonate rock and felsic rock, input of seawater, and groundwater mixing. Boron isotopic compositions (δ11B) range between −9.22 and +39.78 ‰. Sr contents and 87Sr/86Sr ratios are more homogeneous, falling between 0.06 and 32.26 mg/L and between 0.71239 and 0.72121, respectively. The B and Sr isotopic signatures show that three processes contribute to geochemistry of geothermal waters: 1) water/rock interaction involving marine carbonate rock, evaporite, and granitoid or/and gneiss, 2) seawater intrusion, and 3) shallow groundwater mixing. Major-trace element chemistry and these isotope systematics on their own indicates essential information on the aspects of fluid origin or water-rock interaction processes, and however provide a more comprehensive understanding of the geothermal system in the PRD region, South China. • This study presents the first detailed B Sr isotope systematics in the PRD region. • Rock and mixing with groundwater and seawater control geochemistry of hot water. • Evaporation and pollution affect geochemistry of the PRD geothermal water. [ABSTRACT FROM AUTHOR]

[Display omitted] • The parent rocks of detrital spinels in the Upper Triassic sandstones of the Songpan-Ganzi Terrane are ophiolites and stratiform intrusions. • These detrital spinels were mainly recycled from the Lower-Middle Triassic strata of the West Qinling Terrane. • The eastern Paleo-Tethys ocean basin was closed before the Carnian stage. The Late Triassic evolution of the Songpan-Ganzi Terrane in the eastern Tibetan Plateau is crucial for understanding the closure of the eastern Paleo-Tethys Ocean. However, the strong thickening and deformation of sedimentary cover make the Songpan-Ganzi geological records complicated and even obscured, impeding the reconstruction of regional tectonic evolution. In this study, we provide new geochemical data of detrital spinels from the Upper Triassic strata in the eastern Songpan-Ganzi Terrane to reveal the provenance and the regional tectonic events involved in the eastern Paleo-Tethyan closure. Results show that detrital spinels from the Upper Triassic Xinduqiao, Zhuwo, and Zagunao formations have variable concentrations of Cr 2 O 3 (24.36–68.56 wt%), Al 2 O 3 (0.13–39.17 wt%), MgO (0.20–21.25 wt%), FeOT (11.15–48.49 wt%), and TiO 2 (0.00–4.66 wt%). They are geochemically similar to spinels from both ophiolites and stratiform intrusions, and affinitive to the counterparts from island-arc, supra-subduction zone, or mid-ocean ridge settings. Based on comparison with the spinel compositions from adjacent tectonic zones and in combination with previously published evidence from paleogeography, paleocurrent orientation, and geochronology, we propose the detrital spinels from the Upper Triassic sequence in the eastern Songpan-Ganzi Terrane were mainly recycled from the Lower–Middle Triassic strata in the West Qinling Terrane, with minor concentrations derived from the A'nyemaqen ophiolites. This provenance inference presents a new insight into the closure time of the eastern Paleo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]