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Exceptional points (EPs) in non-Hermitian systems have attracted enormous attention and spawned intriguing prospects for the manipulation of waves. Despite many efforts focusing on the exotic behaviors about EPs, there are only a few studies of phase transitions involving multiple EPs. Here, by employing staggered couplings as well as two pairs of on-site gain/loss, we propose a one-dimensional parity-time (P T)-symmetric Lieb photonic lattice and demonstrate diverse phase transitions of such a multiband structure. Owing to the non-Hermitian chiral symmetry, symmetry-protected higher-order EPs are constructed, and the system exhibits P T symmetry breaking beyond a certain threshold. More importantly, both the relative couplings and the on-site gain/loss can be flexibly reconfigured on demand, which yields the degeneracy of different bands, i.e., the emergence of multiple EPs. We also unveil that the EPs will no longer exist in the presence of a non-Hermitian diagonal disorder. In contrast, the spectrum remains symmetric and the EPs, along with the flatband, are robust against the off diagonal disorder due to the preserved non-Hermitian particle-hole symmetry. Our work not only provides a controllable platform for studying EPs but also sheds light on the exciting non-Hermitian physics based on exceptional degeneracies. [ABSTRACT FROM AUTHOR]

The fault activity, tectonic subsidence history, and geodynamics are analysed based on borehole information and seismic datasets from Liaodong Bay. The results reveal that the faults are intensely active (resulting in the faults that are characterized by more lengths and more throws) both in the northern and southern portions of the study area, while the faults are not active in the central portion of the study area during Kongdian Formation and Shahejie Formation deposition. However, the faults are generally more active in the northern portion of the study area than that in the southern portion of the study area. In contrast, the faults are intensely active in central and southern portion of the study area during Dongying Formation deposition. The numerous syn‐depositional faults, which are intensely active, result in southward movement of depositional centre. The tectonic subsidence history of wells (including well JZ‐A, well JZ‐B, well JZ‐C, well JZ‐D, well JX‐A, and well SZ‐A) in Liaodong Bay indicates that it shows obvious episodic tectonic evolution during the Palaeogene in Liaodong Bay. The episodic tectonic movement (initial rifting, rifting climax, thermal subsiding, and strike‐slip rifting) corresponds to Kongdian Formation and Shahejie Formation deposition, and Dongying Formation deposition, respectively. The spatio‐temporal variation of tectonic subsidence history is closely related to fault activity. The analysis results of balanced cross‐sections show that faults are intensely active during Dongying Formation deposition. However, a few faults are much active than that during Shahejie Formation deposition. There is a slight decrease in tectonic activity intensity during Kongdian Formation and Shahejie Formation deposition. In contrast, there is a significant decrease in tectonic activity intensity during third‐member to first‐member of Dongying Formation deposition. The tectonic activity intensity tends to cease by the end of Dongying Formation. [ABSTRACT FROM AUTHOR]

Based on seismic interpretation of 18 regional 3D high‐resolution seismic sections across Liaodong Bay, extension amounts, extension rates and extension coefficients of different seismic sections from the south to the north are calculated by employing balanced section technique. Then, spatio‐temporal distribution of extension amounts is characterized and interpreted. Finally, the analysis of genetic mechanism is conducted and analysed. The results indicate that tectonic evolution in the Paleogene of Liaodong Bay is characterized by episodic extension. Furthermore, spatio‐temporal distribution of extension amounts is relatively uneven. In terms of space, extension amounts are mainly caused by extensional displacement of main depression‐controlled boundary faults and syn‐depositional faults in the depression. In addition, extensional amounts along main depression‐controlled boundary faults are characterized by larger displacement. In terms of time, the periods for horizontal extensional movement can be divided into three stages: The Palaeocene‐Early Eocene (Kongdian Formation‐third member of Shahejie Formation), Middle‐Late Eocene‐Early Oligocene (first and second member of Shahejie Formation) and Middle‐Late Oligocene (Dongying Formation). Among them, extension during the Palaeocene‐Early Eocene occurs both in the north and south of Liaodong Bay. However, extension intensity in the north is stronger than that in the south. Extension intensity in the middle and north during Middle‐Late Eocene‐Early Oligocene obviously increases. In contrast, it is dominated by strike‐slip movement during depositional period of Dongying Formation. Therefore, extension intensity is characterized by significant inheritance. Spatial–temporal distribution of extension amounts is predominantly controlled by tectonic evolution and associated tectonic deformation. [ABSTRACT FROM AUTHOR]

We present the first a priori error analysis of a new method proposed in Cockburn & Wang (2017, Adjoint-based, superconvergent Galerkin approximations of linear functionals. J. Comput. Sci. , 73, 644–666), for computing adjoint-based, super-convergent Galerkin approximations of linear functionals. If |$J(u)$| is a smooth linear functional, where |$u$| is the solution of a steady-state diffusion problem, the standard approximation |$J(u_h)$| converges with order |$h^{2k+1}$|⁠ , where |$u_h$| is the Hybridizable Discontinuous Galerkin approximation to |$u$| with polynomials of degree |$k>0$|⁠. In contrast, numerical experiments show that the new method provides an approximation that converges with order |$h^{4k}$|⁠ , and can be computed by only using twice the computational effort needed to compute |$J(u_h)$|⁠. Here, we put these experimental results in firm mathematical ground. We also display numerical experiments devised to explore the convergence properties of the method in cases not covered by the theory, in particular, when the solution |$u$| or the functional |$J(\cdot)$| are not very smooth. We end by indicating how to extend these results to the case of general Galerkin methods. [ABSTRACT FROM AUTHOR]

The typical wells in Liaoxi Uplift were selected to conduct studies on high‐frequency sequences and their correspondences with the Milankovitch Cycles in Dongying Formation based on integrated analysis of wireline logs and sieve residue logs. The results of well JZ‐E show that 37 ultra‐short‐term cycles, 13 short‐term cycles, 8 mid‐term cycles, and 5 long‐term cycles are identified. Meanwhile, the correspondences between high‐frequency sequences and the Milankovitch Cycles in Dongying Formation were analysed based on GR curve of well JZ‐E and MATLAB procedure. The correspondences indicate that the Milankovitch Cycles are well preserved in Dongying Formation. The thickness of long‐period cycles caused by eccentricity ranges from 2.7963 to 3.9965 m. The thickness of mid‐term cycles caused by obliquity ranges from 1.5081 to 2.1126 m. The thickness of short‐period cycles caused by precessions ranges from 0.5791 to 1.1269 m. There is a good consistency between high‐frequency sequences and the Milankovitch Cycles in Dongying Formation. The mid‐term cycle, short‐term cycle, and ultra‐short‐term cycle of high‐frequency sequence correspond, respectively, to long‐period eccentricity, short‐period eccentricity, and precession cycle of the Milankovitch Cycles. Lacustrine fluctuations caused by the change in Earth's orbit play a major role in controlling high‐frequency sequences. [ABSTRACT FROM AUTHOR]

Research on the provenance of sedimentary systems is key to better understanding the sedimentary framework and improving exploration-associated decision-making and deployment. With regard to the provenance of sedimentary systems, there is still poor understanding in the initial rifting stage due to imbalanced and insufficient exploration and a common lack of seismic data, which have seriously hindered oil exploration in the Qintong Sag, Subei Basin. This study aimed at investigating the provenance in the direction of the fault-terrace zone in the southeast part of the Qintong Sag and aimed to examine whether large-scale sedimentary systems are formed by these sediment sources. Integrated analysis of heavy minerals, sandstone petrologic maturity, drilling cutting dates, 3D seismic data, and well logs was employed to identify the provenance. This study is the first time that large-scale provenance from the direction of the fault-terrace zone has been discovered in the third member of the Paleocene Funing Formation (referred to as the third Mbr of the Funing Fm in this paper) in the Subei Basin, east China. The documentation shows that sediments from the northwest Wubao Low Uplift and the southeast Taizhou Uplift can be distinguished in the Qintong Sag, with the large-scale delta system in the central and eastern part of the Qintong Sag comprising sediments from the Taizhou Uplift, improving upon previous understanding of the sedimentary framework. The deposition formed by the Taizhou Uplift provenance system was characterized by gradual weakening of the hydrodynamic forces, a decreasing sediment supply, and shrinking of the retrogradational delta depositional systems with good reservoir qualities, which are characterized by high-quality source–reservoir–cap combinations and are likely to develop into a hydrocarbon-rich belt. The discovery of the Taizhou Uplift provenance proves that there may be major provenance and large-scale sedimentary systems from the fault-terrace zone of the rift basins in the initial rifting stage. The experience of rapid retrogradation showed that these large-scale delta systems are likely to only flourish in the initial rifting stage. This study is helpful for improving the understanding of sediment provenance and the sedimentary framework of lacustrine rift basins in the initial rifting stage. [ABSTRACT FROM AUTHOR]

The solar radiation or insolation at a specific locality on the Earth's surface is determined by the distance of this point from the sun and by the angle with which the radiation hits the earth's surface. The theory that variations in the earth's orbit determine the amount of radiation and therefore the climate which is the Milankovitch Cycle. In non‐marine lacustrine rift basin, the changes of climate can be recorded by the palaeontology, and it also plays an important role in controlling lacustrine fluctuations. The lacustrine fluctuations are indicated by coastal onlap, which is the landward or lake‐ward onlap of non‐marine coastal deposits. In this paper, based on borehole data, wireline logs, seismic datasets, biostratigraphic data and palaeontology, the lacustrine fluctuation curve can be reconstructed from the onlap of lacustrine deposits in non‐marine sequences. The durations and magnitudes of these changes can be used to construct charts showing cycles of the relative rising and falling of lake level. In addition, the changes of lake level can also be reflected by the palaeontology such as pollen. The living conditions and distributions of pollen can be a good indicator for climate changes and lacustrine fluctuations in an a non‐marine setting. The calculation of the Milankovitch Cycle can be determined by the GR log in the study area which keeps a record of cycle changes. All climatic changes and lacustrine fluctuations are mainly resulted from the Milankovitch Cycles, and therefore, through the reconstruction of lacustrine fluctuations, climate changes and the Milankovitch Cycle, the correspondences among them can be clearly addressed. All the results can contribute a lot in theory research in the study area and lead to a new focus in practical hydrocarbon exploration and exploitation. [ABSTRACT FROM AUTHOR]

The sequence architecture and depositional evolution of Dongying Formation in the steep slope zone are mainly developed in response to tectonism. The comprehensive analysis of cores, wireline logs, and seismic volumes is employed to reveal the relationship among sequence architecture, depositional evolution, and tectonism. The results indicate that the whole Dongying Formation can be divided into three third‐order sequences based on regional unconformity along the basin margin and slope and its correlative conformity in the basin centre. In addition, seven fourth‐order sequences are further divided based on regression surfaces within third‐order sequences. The sequence architecture of different‐order sequences is discussed and revealed in terms of systems tracts, stratal thickness and distribution, and seismic reflections. Four genetic types of sedimentary facies including fan delta, sublacustrine fan, near‐shore subaqueous fan, and braided delta are identified according to core observations, stacking patterns of wireline logs, internal configuration, and external geometry of seismic reflections. The depositional evolution in Dongying Formation is related to tectonic intensity and tectonic evolution stage in the steep slope. The whole Dongying Formation is in the midst of a strike‐slip and rifting stage during its depositional period. When tectonic movements are intensively active, it is mainly characterized by fan delta and near‐shore subaqueous fan along the steep slopes and sublacustrine fan in the basin centre. However, the opposite case is dominated by fan delta and braided delta around and along the uplifts. In addition, the palaeogeomorphology and sediment supply also play an important role in controlling facies distributions in the steep slope zone. The subsidence rate resulted from tectonism controls the sequence architecture and depositional filling in terms of fault activities and accommodation space in the steep slope. [ABSTRACT FROM AUTHOR]

The Xiayan Rise (Junggar Basin, NW China) preserves a record of fluvial–deltaic–lacustrine, low‐accommodation deposits of the Lower Jurassic Sangonghe Formation. Sequence stratigraphy, depositional systems, and petroliferous plays are investigated with seismic sections, wireline logs, and cores. The results indicate that two third‐order sequences and eight fourth‐order sequences are recognized. The sequence architecture is controlled by episodic tectonic movement, sediment supply, and climate. In addition, several sedimentary microfacies are identified including braided delta deposits and shore‐shallow lacustrine deposits. During the depositional period of J1s22, basin tectonics result in a decrease in water depth and accommodation space. Subaqueous distributary channels are wide and flat which superimpose and connect with each other. During the depositional period of J1s21‐2, tectonic movement results in increasing water depth and accommodation space during a phase of warm and humid climate. During the depositional period of J1s21‐1, the accommodation space was limited but sediment supply continued which is easy to form forced regression. Low rates of tectonic subsidence and low accommodation space results in the distribution of isolated subaqueous distributary channels which resulted from lacustrine depth. Petroliferous plays comprising source rocks, reservoirs, and seals can be found in LST1 and LST2. [ABSTRACT FROM AUTHOR]

The southwestern slope of Lufeng Depression, which is located in the central part of Zhu I Depression is a significant geomorphic unit due to its petroliferous discoveries and tectonic evolutions since early Palaeogene. Based on the comprehensive analysis of cores, wireline logs, seismic volumes, and other related geological and geophysical information, the sequence architecture and depositional evolution was analysed, and their responses to regional tectonic processes and base‐level changes were revealed. The results indicated that two second‐order sequences and six third‐order sequences defined by different types of sequence boundaries are recognized. The second‐order and third‐order sequences were bounded by regional erosional unconformities on the depression margin or slope and unconformities in the central depression with the assist of stacking patterns of wireline logs and depositional characteristics of cores. The second‐order sequence generally consists of two regional transgressive–regressive cycles which can be further subdivided into several local sub‐cycles equivalent to corresponding third‐order sequences which can be identified from wireline logs and cores. The palaeogeomorphology resulted from compound and complex tectonic events in the early Palaeogene plays an important and main role in controlling sequence architecture. In contrast, the base‐level changes largely controls the sequence architecture in the late Palaeogene. The depositional systems within the sequence stratigraphic framework are mainly composed of braided delta deposits and shore deposits, which respectively includes braided channel, subaqueous distributary channel, lacustrine shale, beach bar, maximum flooding surface, shoreface, and foreshore. The base‐level changes, which apparently originated from tectonic uplift and subsidence and sediment supply, controlled the regional transgressions and regressions in sedimentary facies distributions. The development of subsequence (what we call it sand units or sections) from 2,980 to 2,880 in Enping Formation in the Early Palaeogene is obviously influenced by a decrease in tectonic subsidence (rifting stage) and an increase in accommodation space (base‐level rising), while the case is opposite in subsequence 2,850 of Enping Formation. However, the subsequence in Zhuhai Formation in the late Palaeogene from 2,760 to 2,600 was formed in stable tectonic settings (transition stage), and thereby, it was mainly dominated by base‐level changes which were caused by sediment supply and accommodation space changes. [ABSTRACT FROM AUTHOR]

The Zhuhai Formation in Lufeng Depression is mainly deposited during a depression stage. In this paper, we employ cores, wireline logs, and seismic reflections to reveal sequence architecture and depositional evolution in target intervals. The results indicated that one second‐order sequence and two third‐order sequences were identified and sequence stratigraphic framework was established. The second‐order sequence was developed in response to base‐level falling, while third‐order sequences were mainly formed during base‐level rising. In addition, each third‐order sequence did not change too much in thickness. Then the shore deposits (shoreface and foreshore) were delineated, and the depositional characteristics were described within the framework with the help of related data. The shoreface and foreshore deposits within the sequence stratigraphic framework varied significantly in stacking patterns of wireline logs and cores. Based on comprehensive analysis, it can be concluded that base‐level changes played an important role in controlling sequence architecture. And lacustrine fluctuations derived from accommodation space changes exerted an essential effect on depositional evolution. This study provides significant insights into revealing the sequence architecture and depositional evolution and discussing hydrocarbon potential in the transition stage in the Zhuhai Formation. [ABSTRACT FROM AUTHOR]

The seismic merging dataset, wireline logs, core photographs, thin sections, and other geological information were employed to investigate sequence architecture and reveal depositional evolution of Enping Formation in Lufeng Depression, Pearl River Mouth Basin. The results showed that one second‐order sequence and four third‐order sequences were identified based on the unconformities along basin margin/slope and correlative conformities in the basin centre. In addition, several associated sedimentary facies or microfacies (including braided channel deposits, subaqueous distributary channel deposits, beach‐bar deposits, and so on) that were recognized within sequence stratigraphic framework and depositional evolution were revealed by well tie–seismic correlations with seismic attributes extracted from the stratal slicing in terms of sand sections/units in Enping Formation. It was characterized by progradational process from seismic attributes in general that the delta deposits gradually retrograded. Through comprehensive analysis, it can be concluded that episodic tectonic movements and subsequent uplift played an important role in controlling sequence architecture. Sediment supply and lacustrine level fluctuations derived from accommodation space changes exerted an essential effect on depositional evolution. This study provides new and robust insights into understanding the sequence architecture, depositional evolution, and hydrocarbon exploration in Enping Formation. In addition to the significance for academia, study of sequence architecture and depositional evolution are of great importance for hosting potential hydrocarbon reserves, because they are frequently related to important and potential reservoirs. Consequently, investigating sequence architecture and depositional evolution are significant economically as well. [ABSTRACT FROM AUTHOR]

This research study presents the results of an integrated study employing core samples, wireline logs, and seismic dataset collected in the study area for analysing the syn‐depositional fault's control of the evolution of the axial meandering river delta‐sublacustrine fan deposits during the Ed2x depositional period. The results indicate that the delta deposits that had developed during a retrogressive period, with the characteristics of retrogressive stacking patterns, had resulted from a high subsidence rate caused by the syn‐depositional faults with large fault throw. These appeared to be characterized by strong amplitude, low frequency, and continuous seismic reflections on the seismic profiles, and high‐amplitude serrated cylinder‐shaped stacking patterns in the wireline logs, with no obvious sedimentary structures. In contrast, the delta deposits developed during a progressive period and characterized by progressive stacking patterns were determined to have resulted from a low subsidence rate caused by the syn‐depositional faults with small fault throw. They were found to be characterized by weak‐to‐medium amplitude vermicule‐shaped seismic reflections, as well as low‐amplitude bell‐shaped or funnel‐shaped stacking patterns, with soft‐sediment deformation structures. [ABSTRACT FROM AUTHOR]

Hulun Lake is located in Northeast China and is a well‐exposed modern lacustrine rift basin. In this study, recent fieldwork has demonstrated that it was mainly filled by alluvial fan and fan delta deposits along the western escarpment, which were controlled by the Eerguna Fault Zones. However, it was filled by river‐deltaic and eolian deposits along the eastern slope. The distributions of the depositional systems were found to be controlled by their positions within the basin. The western escarpment was determined to have influenced the distributions of the alluvial fan and fan delta deposits. In contrast, the river‐deltaic and eolian deposits were controlled by the sediment supply, paleogeomorphology, and wind forces. The asymmetric geometry of the basin was determined to have resulted in different facies associations. First, a region of maximum sediment thickness and high‐gradient escarpment was found to be located near a normal fault foot (Eerguna Fault). Second, a region of a shallower and low‐gradient slope was located near the margin of a river‐lake transition. The depositional characteristics obtained from the prospecting trench indicated that the coarse deposits on the western side were mainly derived from unexpected flooding, gravity, and episodic flooding in an ascending order. In contrast, the fine deposits on the eastern side were mainly sourced from a meandering river. A clear understanding of controlling factors on facies associations can potentially reveal the sedimentary process and evolution of the depositional systems, as well as provide an important methodology for the prediction of facies in other sedimentary basins with similar characteristics. [ABSTRACT FROM AUTHOR]

Large sublacustrine fan deposits have been identified within the lacustrine successions of the second member of the Palaeogene Dongying Formation in the Liaozhong Depression. In this study, by using comprehensive and detailed analyses of the borehole lithology, limited cores, wireline logs, and seismic facies, 4 types of sublacustrine fan deposits were identified and characterized. Then, an integrated depositional model was established based on the above investigations. The result indicates that the geophysical characteristics of the different sublacustrine fan deposits differed from each other, in terms of their internal configuration and external geometry of seismic reflections, and stacking patterns of wireline logs, and stratigraphic position in the vertical successions. Subsequently, the model was established according to the comprehensive analysis of the geophysical characteristics and stratigraphic position. The discussion of developing conditions and hydrocarbon discoveries within different types of sublacustrine fan deposits provided robust insights regarding how to locate and evaluate reservoirs in such deposits. Furthermore, the results of this study may potentially assist in achieving a new understanding of how to identify sublacustrine fan deposits in similar lacustrine basins and may also assist in making further decisions regarding the terms of hydrocarbon migration and accumulation. [ABSTRACT FROM AUTHOR]

This paper presents a novel, fully computable error approximation and mesh adaptation approach for functionals defined by second-order elliptic equations. The functionals are approximated by the hybridizable discontinuous Galerkin (HDG) method and the error approximation is obtained by the adjoint-based method and a local post-processing technique of the HDG method. Unlike most adjoint-based error estimations in the literature, the novelty of our method is that the error approximation is obtained without requiring an auxiliary finer mesh or higher order approximation spaces for solving the adjoint problem. This reduces the computational cost and eases the implementation of the problem. What's more, the local post-processing technique can be carried out in parallel, which speeds up the method even more. We illustrate the method with a second-order elliptic problem and we present examples of three types of functionals: volume integrals; boundary integrals and eigenvalue problems. Numerical tests with adaptive mesh refinements for non-smooth solutions are presented to show that our method is efficient and robust. • Propose a novel error approximation and mesh adaptation method for approximating functionals. • Observe the convergence rate of 2k+1 for non-smooth solutions with adaptivity in the numerical experiments. • Present the general framework of the method and give two linear and one nonlinear functional examples. [ABSTRACT FROM AUTHOR]

• Propose a high-order accurate method for approximating eigenvalues defined in terms of Galerkin approximations. • Extend a novel adjoint-based approach for non-linear functional outputs. • Uncover a possible a posteriori error estimate for output functionals. We present a new method for computing high-order accurate approximations of eigenvalues defined in terms of Galerkin approximations. We consider the eigenvalue as a non-linear functional of its corresponding eigenfunction and show how to extend the adjoint-based approach proposed in Cockburn and Wang (2017) [14] , to compute it. We illustrate the method on a second-order elliptic eigenvalue problem. Our extensive numerical results show that the approximate eigenvalues computed by our method converge with a rate of 4 k + 2 when tensor-product polynomials of degree k are used for the Galerkin approximations. In contrast, eigenvalues obtained by standard finite element methods such as the mixed method or the discontinuous Galerkin method converge with a rate at most of 2 k + 2. We present numerical results which show the performance of the method for the classic unit square and L-shaped domains, and for the quantum harmonic oscillator. We also present experiments uncovering a new adjoint-corrected approximation of the eigenvalues provided by the hybridizable discontinuous Galerkin method which converges with order 2 k + 2 , as well as results showing the possibilities and limitations of using the adjoint-correction term as an asymptotically exact a posteriori error estimate. [ABSTRACT FROM AUTHOR]

The sequence architecture and depositional evolution in Cenozoic Liaodong Bay, Bohai Bay Basin are formed mainly in response to rifting and lacustrine fluctuations which have been documented by integrated analysis of seismic reflections, well logs, lithology associations and core analysis. Four depositional-geomorphological systems are identified comprising fan delta systems, near-shore subaqueous fan systems, beach-bar systems and braided river delta systems. Three composite sequences (CS) are recognized including CS IV (S4), CS III (S3-3, S3-2, S3-1), and CS II (S2). The identification and description of sequence boundaries in different composite sequences vary from each other due to database. CS IV (S4) is difficult to identify across the whole area. CS III (S3-3, S3-2, S3-1) is bounded by regional unconformities along the slope or on the uplift and correlative conformities in the central depression. CS II (S2) is locally bounded by regional unconformities according to seismic resolution. The geomorphical processes and fault activities, during different stages of rifting, in addition to overlapping effects of lacustrine fluctuations, sediment supply and climate changes control composite sequences and depositional-geomorphological systems. Finally, fan delta systems and braided river delta systems are proposed to host petroleum reserves. • The anatomy and characters of depositional-geomorphological systems varies from each other. • Composite sequences are bounded by regional unconformities and correlative conformities. • The rifting in different stages and locations play different roles of controlling. • Controls of lacustrine fluctuation overlap with effects of sediment supply and climate. [ABSTRACT FROM AUTHOR]

The Ordos Basin, as one of the most petroliferous basins in China, hosts 12.9 billion tons of oil reserves and 15.2 trillion cubic meters of natural gas reserves. The extensive hydrocarbon exploration and production shows that the southeastern Ordos Basin contains considerable potential in the Shanxi Formation and Lower Shihezi Formation. In this study, cores, wireline logs, thin sections, and heavy minerals are employed to carry out research on classification of sequence stratigraphy, identification of sedimentary facies, reconstruction of palaeo‐geomorphology, analysis of sediment supply, palaeo‐climate, and accommodation space changes. The results indicate that palaeo‐geomorphology gradient tends to be steep, which results in increasing hydrodynamics and turns to be wide and flat which results in decreasing accommodation space. In addition, heavy mineral distribution reveals the direction of sediment supply which indicates provenance changes. The palaeo‐climate changes commonly cause differences in lithology associations, monsoon and vegetation properties. The differences in temperature and humidity result in different colours of lithology associations which indicate various sedimentary environments. The prevalence of monsoon assists in the preservation of fluvial delta by controlling lateral migration of rivers through affecting vegetation and lithology associations. The accommodation space variations control the development of fluvial delta and result in various depositional characteristics of fluvial delta. All these factors trigger the transition from meandering river delta to braided river delta. The reconstruction of the transition and analysis of controlling factors play an important role on understanding the sedimentary evolution of analogous reservoir successions. [ABSTRACT FROM AUTHOR]

Metagenomic sequencing (mNGS) is a powerful diagnostic tool to detect causative pathogens in clinical microbiological testing owing to its unbiasedness and substantially reduced costs. Rapid and accurate classification of metagenomic sequences is a critical procedure for pathogen identification in dry-lab step of mNGS test. However, clinical practices of the testing technology are hampered by the challenge of classifying sequences within a clinically relevant timeframe. Here, we present GPMeta, a novel GPU-accelerated approach to ultrarapid pathogen identification from complex mNGS data, allowing users to bypass this limitation. Using mock microbial community datasets and public real metagenomic sequencing datasets from clinical samples, we show that GPMeta has not only higher accuracy but also significantly higher speed than existing state-of-the-art tools such as Bowtie2, Bwa, Kraken2 and Centrifuge. Furthermore, GPMeta offers GPMetaC clustering algorithm, a statistical model for clustering and rescoring ambiguous alignments to improve the discrimination of highly homologous sequences from microbial genomes with average nucleotide identity >95%. GPMetaC exhibits higher precision and recall rate than others. GPMeta underlines its key role in the development of the mNGS test in infectious diseases that require rapid turnaround times. Further study will discern how to best and easily integrate GPMeta into routine clinical practices. GPMeta is freely accessible to non-commercial users at https://github.com/Bgi-LUSH/GPMeta. [ABSTRACT FROM AUTHOR]

The Tarim Basin, located in Western China, is a large sedimentary basin with a long geological evolution history stretching from the Sinian (Ediacaran) to the Neogene period. An enormous deep‐water gravity flow system, up to 3,000–5,000 m in thickness, developed during the Late Ordovician in the central and northern parts of the basin, with the great potential for forming large lithologic‐stratigraphic oil/gas traps. However, the poorly‐understood reservoir condition has caused oil/gas exploration to fall to a standstill. Based on several seismic surveys, well profiles, and outcrop data, this study focuses on sequence‐depositional systems, paleo‐geomorphology, and paleo‐geography of the Late Ordovician reservoir rocks. The goal is to probe into the relationship between different types of deep‐water gravity flow systems and the paleo‐geomorphology, taking the tectonic development into account. Three different depositional models are applied to interpret the deep‐water gravity flow systems preserved in the Upper Ordovician succession. The latter are distributed in the Tabei, Tazhong, and Tadong areas underneath the great deserts, respectively. During the Late Ordovician, the Tazhong area seemed to be a debris‐flow‐dominated setting with shallow, sandy channelized systems controlled by multiple slopes. The Tabei area was a debris‐flow‐dominated setting with few U‐shaped deep incised ditches filled with muddy debris, and the Tadong area a typical submarine turbidite‐dominated fan system in that time. These depositional models also attempt to predict the favourable reservoir sand bodies and lithologic‐stratigraphic oil/gas traps with the Upper Ordovician successions in the subsurface of the Tarim Basin. [ABSTRACT FROM AUTHOR]

In this article, the metal-insulator-metal based Fano resonance biosensors in mid-infrared are numerically investigated. The continuum states and discrete states of Fano resonances are produced by two asymmetric stubs and a symmetric ring, respectively. The quadruple Fano modes can be individually modulated for refractive index sensing in the mid-infrared spectral region (3–10 µm), which covering the characteristic infrared vibrations of specific molecular species. The maximum sensitivity and figure of merit is up to 7550 nm/RIU and 302, respectively. Moreover, the temperature sensing in ethanol and the concentration sensing in glucose solution indicate that the waveguide can not only quantify the temperature and concentration of the solution through the Fano resonance, but also characterize the chemical information of sample through the mid-infrared absorption. And the optimized MIM waveguide can effectively prevent the absorption of the aqueous solution disturbs the transmission spectrum and enhance the mid-infrared absorption of solvents. The excellent performances demonstrate the tunable multiple Fano resonance based on MIM waveguide is a promising method for biosensing in mid-infrared. [ABSTRACT FROM AUTHOR]

As one of the major exploration objects of marine deposit in Tarim basin, Silurian has been paid more attention from oil/gas exploration and geologists. However, due to the widely deposit and later erosion, it is difficult to restore the original basin. The surrounding tectonic activity and provenance systems of Silurian Tarim basin have a lot of controversy. Aid of detrital zircons U-Pb dating data obtained from well drilling of Tabei (塔北) and Tazhong (塔中) areas and Sishichang (四十场) and Xiangyangcun (向阳村) outcrop profiles, integrated with other geological and geophysical data, the tectothermal evolution and provenance nature of Silurian deposit have been revealed. Zircons U-Pb dating shows Tarim basin has experienced 5-6 significant tectothermal events: 3 500-3 000 Ma Paleo-Mesoarchean, around 2 500 and 1 800 Ma Paleoproterozoic, around 1 000 and 800 Ma Neoproterozoic, and 500-400 Ma Eopaleozoic tectothermal events. These tectothermal events reflected the evolution of Tarim microplates and Tarim basin, respectively, corresponded to the forming and spilitting process of Ur supercontinent, Kenorland, Columbia and Rodinia supercontinent. Difference between the samples of Tazhong and Tabei areas indicated that North and South Tarim microplates were different in Paleo-Mesoarchean, and later evolutions were more synchronous after Paleoproterozoic. Integrated with seismic data and outcrop interpretation, the U-Pb dating results also revealed that the surrounding tectonic activities were still very active during Silurian, and indicated different regions had different source systems. At Tadong (塔东) and Manjiaer (满加尔) depressions, major source systems came from Ordovician Altyn orogenic belts. At Tabei area and northwest of Tarim basin, major source systems came from recycling orogenic zone (the activity of South Tianshan (天山) Mountain) and Precambrian stable basement (local paleo-uplifts at north of Tabei). The Ordovician uplift and orogenic zone at the south of Tarim basin and Precambrian granite basement provided lots of source systems to Tazhong area. [ABSTRACT FROM AUTHOR]

A robust generalized analytical expression for resonance frequencies of plasmonic nanoresonators, which consists of folded rectangular structures, is proposed based on a circuit route. The formulation is rigorously derived from the lumped circuit analogue of the plasmon resonance in a rectangular metallic nanorod. Induced by the nonhomogeneous charge distributions in the plasmonic resonators of rectangular end-caps, the electromagnetic forces drive the harmonic oscillations of free electrons in the plasmonic nanoresonators, generating intrinsically nonlinear shape-dependent LC resonance responses. Even for the plasmonic nanoresonators with much larger structure sizes than the skin depths, the significant frequency deviations due to the phase-retardation behavior can still be adequately described by the generalized expression. Moreover, for a large range of plasmonic nanoresonators with various folded rectangular geometries, sizes and materials, the generalized analytical expression gives the underlining physics and provides accurate predictions, which are perfectly verified by a series of numerical simulations. Our studies not only offer quantitative insights of nearly any plasmonic nanoresonators based on folded rectangular geometries, but also reveal potential applications to design complex plasmonic systems, such as periodic arrays with embedded rectangular nanoresonators. [ABSTRACT FROM AUTHOR]