Large Number Of Faults Research Articles

აჭარა-გურიის გეოლოგიური აგებულება მიღებული მაღლივი-კოსმოსური მასალების დეშიფრირებით

The geological structure of the Adjara-Guria region is defined by the fault zones of the orthgonal-diagonal system, which are the constituent parts (segments) of the transregional lineaments, and are well interpreted on high-space images.The block structure of the regionis determined by fault zones. Nine tectonic blocks of different configurations and geological structures are separated. There are deciphered 11 and 12 km wide tectonic zones with meridian direction, compiled,replaced by a large number of faults and related dykes. The gold occurencesin the region are associated with meridian structures, that’s why the identified tectonic zones are promising spaces for gold.

Effects of differential tectonic activities on overpressure evolution in the deep-water area of the Qiongdongnan Basin: implications for gas hydrate accumulation

The lack of data on the complex tectonics of the Qiongdongnan Basin has thus far restricted our understanding of the overpressure, deep hydrocarbon and shallow gas hydrate distribution. We therefore combined integrated seismic, well and borehole test data with basin models to clarify the relationship between tectonic activity and overpressure evolution, as well as the potential effects of the subsurface pressure on gas hydrate accumulation. The results show differences in tectonic activity and pressure characteristics between the eastern and western basins. Large numbers of faults and magmatic intrusions have developed in the post-rift layer of the eastern basin (the Baodao to Changchang sub-basins) since the Late Miocene ( c. 10.5 Ma), although they seldom formed in the western basin (the Lengdong to Lingshui sub-basins). Correspondingly, the eastern basin was characterized by lower overpressures (up to 40 MPa) and the western basin displayed higher overpressures (up to 110 MPa). The results indicate that tectonic activity since c. 10.5 Ma caused the relief of overpressure in the eastern basin. In stark contrast, the overpressure in the western basin increased significantly due to the lack of structural conduits and rapid sedimentation of the thick Pliocene and Quaternary deposits. Numerical models reveal that the faults and gas chimneys associated with the intrusions constituted shallow plumbing systems through which deep natural gas was able to migrate upwards. The formation of gas hydrates relied on the migration of deep gas to the hydrate stability zone below the seafloor. The relatively lower overpressured zones due to pressure relief in the eastern basin are therefore considered the next areas potentially favourable for the formation of gas hydrates. Thematic collection: This article is part of the Emerging knowledge on the tectonics of the South China Sea collection available at: https://www.lyellcollection.org/topic/collections/south-china-sea

Fault resilience in network of energy harvesters

Energy harvesters (EH) that scavenge energy from ambient environment are gaining popularity and are used for powering low demand devices on account of their low power outputs. Enhancement of the power is achieved through an array or network of identical EH. The focus of this study is on investigating how the network topology affects the harvesting efficiency per EH, using complex network theory. The studies are presented with respect to vibration induced EH, specifically, the commonly used network of coupled pendulums oscillating in a magnetic field, with the pendulum supports being subjected to vibrations. Questions on the EH efficiency are investigated with respect to the number of EH in the network, its topology and the effects of faults which lead to loss of regularity. Additionally, the effects of parametric random variabilities in the individual EH are investigated with respect to the harvesting efficiency. This study shows that EH efficiency is best for regular networks, can be enhanced by increasing connectivity but up to a limit and is resilient against few local faults. The performance drops with larger number of faults or due to parametric uncertainties. The findings of this study are expected to be of use in design and maintenance of EH networks.

Improving the reliability in bio-nanosensor modules using hardware redundancy techniques

A nano-robot is a controlled robotic system at the nanoscale. Nowadays, nanorobotics has become of particular interest in medicine and pharmacy. The accurate diagnosis of the diseases as well as their rapid treatment will make everyone surprised and will significantly reduce the associated risks. The modeling of reliability in biosensors is studied for the first time in this paper. The use of practical hardware redundancy has turned into the most cost-effective to improve the reliability of a system. Additionally, the Markov model is used to design fault-tolerant systems in nanotechnology. The proposed method is compared with some existing methods, such as triple modular redundancy and non-fault-tolerant systems; it is shown that using this method, a larger number of faults between 3-5 can be tolerated. Using the proposed method, the number of modules can be increased to nine. However, a larger number than 9 MR is not recommended because of an increased delay and requiring more hardware. As the scale of components used in digital systems has gotten smaller, the use of hardware redundancy has become cost-effective. But there is a trade-off between the amount of used hardware and fault tolerance, which can also be investigated.

Water Projects in Ethiopia and their Implications for the Future of the Nile Water

Ethiopia is well known as the “East Africa water tower.” Water flows from it in all directions, north and west to the Nile River (Sudan and Egypt), And south to Lake Turkana (Kenya), Shabelle and Juba (Somalia). To the east, Lake Assal (Djibouti), Mountainous nature, and complex terrain dominate Ethiopia. Rainwater and its run-off mountain slopes and hills are the source of surface water for most Ethiopian lands. This paper discusses Ethiopia’s water situation, as the primary source country, which contributes about 85% of the Nile’s water, and discusses Ethiopia’s possibility to establish great dams. And the most important geological reasons behind the failure of many water projects in Ethiopia, whether on a large or small scale. Including the temporal and spatial diversity of rainfall, the high evaporation rate (87%), the different terrain, the severity of the slopes, the spread of weak basaltic volcanic rocks and fractured limestone, and a large number of faults and faults as a result of the seismic activity associated with the African trench, as well as the increase of the Ethiopian plateau. Alluvial sedimentation that negatively affects the storage capacity of dams.It also aims to assess the impact of existing or under-construction water projects on the water share of Egypt and Sudan and to identify future water projects in Ethiopia by analyzing previous data, reports, and scientific research, and finally finding ways to get out of the current crisis between countries The source on one side and the downstream countries (Egypt and Sudan) on the other side.

Influence of Multi-Period Tectonic Movement and Faults on Shale Gas Enrichment in Luzhou Area of Sichuan Basin, China

The Luzhou area in the southern Sichuan Basin has experienced multiple tectonic movements, forming a complex fault system; the activity has an important impact on the enrichment of shale gas in this area. In order to reveal the influence of the fracture system on the differential enrichment of shale gas, this paper takes the southern Sichuan Basin as the research object. The structural evolution process and fracture development characteristics of the different tectonic units in Luzhou area of southern Sichuan were characterized by conducting a seismic profile analysis, structural recovery using a back-stripping method, and core hand specimen description. We clarified the control effect of the structural deformation and fracture on the differential enrichment of shale gas, and we established a differential enrichment model of shale gas in the Luzhou area. The results show that: (1) The Luzhou area has undergone the transformation of a multi-stage tectonic movement. There are many sets of detachment structures in the longitudinal direction, and the plane structural form is a thin-skin fold-thrust belt composed of wide and narrow anticlines in the north–south direction. (2) The faults in the study area are affected by the Himalayan tectonic movement. The high-angle reverse faults are developed, and the number of large faults is small. The second and third faults are mainly developed. The second faults are only developed at the high position of the structure, which has a significantly destructive effect on shale gas reservoirs, while the third and fourth faults have no significant destructive effect on shale gas reservoirs. (3) In the study area, the types of cracks are categorized into transformational shear cracks, bed-parallel shear cracks, intraformational open cracks, lamellation cracks, shrinkage cracks, and abnormal high-pressure cracks. The thickness of the shale rock mechanical layer, brittle mineral content, and organic matter content jointly control the crack development degree in the shale of the Wufeng–Longmaxi Formation. (4) The uplift erosion, structural deformation, and fracture development caused by the structural evolution have affected the preservation of shale gas, resulting in the differential enrichment of shale gas reservoirs in the region. Based on the enrichment factors of shale gas, we established a differential enrichment model of shale gas in typical structural units and optimized the favorable enrichment areas, which are important contributions for guiding shale gas exploration and development in the Sichuan Basin.

Influence of a Dominant Fault on the Deformation and Failure Mode of Anti-dip Layered Rock Slopes

Toppling is a kind of failure mode that commonly exists in anti-dip rock slopes. Toppling deformation has a great influence on the stability of rock slopes, which often leads to geological disasters such as sliding and collapse of anti-dip slopes. However, a large number of faults and other structural planes will be produced in many rock slopes due to the action of geological structure movement. In the investigation, it is found that there are not only toppling deformation, but also faults and other geological structures in the toppling deformation rock slope. Previous studies have calculated the depth of toppling deformation, which is considered from the development characteristics of toppling deformation itself. In this paper, based on the field investigation of the anti-dip rock slope with bedding faults, the relationship between the depth of toppling deformation and the location of faults is analyzed by three-dimensional discrete element method. When the dominant structural plane and toppling fracture surface exist at the same time, the main factors affecting the failure of the reverse dip rock slope can be obtained by determining the different depths of the two planes. The final failure depth and failure mode of the toppling deformation in an anti-dip rock slope with a dominant structural plane can be preliminarily determined.

Fault Tolerant Control Based SFO-Intelligent PID: Application on SynRM for Flywheel Energy Storage Systems -Part I

Reliability, safety, and fault-tolerant control (FTC) for power systems are substantially raised in several industrial applications. It is critical to correctly diagnosis the faults occurring in a drive system to avoid harmful accidents and to ensure continuity of operation. It is necessary to design proper control techniques to recover the faulty system’s performance/functionality to its nominal level. This research work divided into two parts a design scheme of intelligent fault-tolerant control based artificial intelligence techniques (AI) is described and implemented integrates common knowledge acquisition methods with techniques developed in the fields of model-based diagnosis (MBD) to reach the so-called towards intelligent fault tolerant control to provide reliability and maintain the stability of the system in desired performance automatically; This paper presents the first part of this scheme proposes stator-flux oriented (SFO) control with GA-tuned proportional-integral-derivative (PID) controller. The principle is to set the q axis component of stator current invariant during healthy and faulty operating mode. The overall development scheme is summarized and an example illustrates features of the methods performed on a 1.0kW SynRM drive. Results presented have shown that the FT controller scheme developed is potentially capable of dealing with a larger number of faults and can successfully keep a good dynamic performance during faulty mode.

Multiple-Searching Genetic Algorithm for Whole Test Suites

A test suite is a set of test cases that evaluate the quality of software. The aim of whole test suite generation is to create test cases with the highest coverage scores possible. This study investigated the efficiency of a multiple-searching genetic algorithm (MSGA) for whole test suite generation. In previous works, the MSGA has been effectively used in multicast routing of a network system and in the generation of test cases on individual coverage criteria for small- to medium-sized programs. The performance of the algorithms varies depending on the problem instances. In this experiment were generated whole test suites for complex programs. The MSGA was expanded in the EvoSuite test generation tool and compared with the available algorithms on EvoSuite in terms of the number of test cases, the number of statements, mutation score, and coverage score. All algorithms were evaluated on 14 problem instances with different corpus to satisfy multiple coverage criteria. The problem instances were Java open-source projects. Findings demonstrate that the MSGA generated test cases reached greater coverage scores and detected a larger number of faults in the test class when compared with the others.

Pyrolytic data verification in potential assessment and catagenetic transformation of the Proterozoic low-carbon formations of Eastern Siberia

The ancient Precambrian formations of Eastern Siberia include oil and gas source rock (SR) interlayers, but in most cases, they can’t be classified as high-carbon ones, because the actual organic carbon content in these strata is low and rarely exceeds 10%. This point effect the approach to the available geochemical data interpretation and the method of quality samples selection. The aim of the work was to determine methods for pyrolytic data verification and the oil and gas Lower Vendian SR quality assess, that based on the results of geochemical researches. It was identified, that before SR catagenetic transformation analyzation by the Tmax parameter and determining the OM type, samples with a low generation potential or with the migrated bitumen presence should be excluded from the consideration. The presence of secondary epigenetic bitumen also indicates the active HC fluids migration within the basin. After data verification, the SR properties were assessed. So lower Vendian SRs have OM with a satisfactory and high generation potential, second type and low maturity in most cases. The oil and gas window zones are located within large depressions and troughs. In addition, the local heating was noted in zones with a large number of faults, where the heating was conducted due to the intrusions introduction and the hydrothermal fluids action.

Seismic characteristics of polygonal fault systems in the Great South Basin, New Zealand

Abstract A well-developed multi-tier polygonal fault system is located in the Great South Basin offshore New Zealand’s South Island. The system has been characterised using a high-quality three-dimensional seismic survey tied to available exploration boreholes using regional two-dimensional seismic data. In this study area, two polygonal fault intervals are identified and analysed, Tier 1 and Tier 2. Tier 1 coincides with the Tucker Cove Formation (Late Eocene) with small polygonal faults. Tier 2 is restricted to the Paleocene-to-Late Eocene interval with a great number of large faults. In map view, polygonal fault cells are outlined by a series of conjugate pairs of normal faults. The polygonal faults are demonstrated to be controlled by depositional facies, specifically offshore bathyal deposits characterised by fine-grained clays, marls and muds. Fault throw analysis is used to understand the propagation history of the polygonal faults in this area. Tier 1 and Tier 2 initiate at about Late Eocene and Early Eocene, respectively, based on their maximum fault throws. A set of three-dimensional fault throw images within Tier 2 shows that maximum fault throws of the inner polygonal fault cell occurs at the same age, while the outer polygonal fault cell exhibits maximum fault throws at shallower levels of different ages. The polygonal fault systems are believed to be related to the dewatering of sedimentary formation during the diagenesis process. Interpretation of the polygonal fault in this area is useful in assessing the migration pathway and seal ability of the Eocene mudstone sequence in the Great South Basin.

Geological modeling of thin and poor reservoir based on well seismic multi-disciplinary

The reservoir physical properties of Tai X block are poor and the major development are thin and poor layers. The average porosity is 18.9% and the air permeability is 22.3×10−3μm2, the Tai X block is a low-permeability reservoir. The block has the characteristics of large area, large number of faults, dense distribution of small faults and complex intersection conditions. It is difficult to obtain a high accurate geological model by using only logging data or seismic data, resulting in inaccurate stratiraphic interpretation results. Therefore, the joint well-seismic technique is used to combine logging data with seismic data to achieve the purpose of accurately identifying faults and establishing complete reservoir structure, and successfully deployed a horizontal well across the fault.

Research on Production Vehicle Evaluation Method of China VI OBD for Light-Duty Vehicles

With the gradual tightening of light-duty vehicle emission regulations, the fault diagnosis function of the on-board diagnostic (OBD) system is constantly improving and the monitoring items are also increasing. The production vehicle evaluation (PVE) test problem of latest OBD certification in the China VI emission regulations for light vehicles is studied. Firstly, the working principle and development process of OBD system is introduced. Secondly, the PVE testing regulations and testing process of OBD system is analyzed. It covers standardized verification (J1), monitoring requirement verification (J2) and in-use monitoring performance verification (J3). Finally, in order to improve the efficiency of PVE testing for such a large number of faults, a faults classification method based on fault type and function is proposed. OBD faults can be simplified into the six categories, which include circuit fault, tool performance fault, hardware performance fault, bus communication fault and exemption test fault. The simulation method of corresponding fault is introduced and analyzed as well.

Target Faults for Test Compaction Based on Multicycle Tests

The use of multicycle tests, with several functional capture cycles between scan operations, contributes significantly to the ability to compact a test set. Multicycle tests have the added benefit that they can contribute to the detection of defects with complex behaviors that are not detected by single-cycle or two-cycle tests. To ensure that this benefit is materialized when test compaction is applied to transition faults, this article suggests to incorporate into the test compaction procedure an additional fault model whose fault coverage increases when multicycle tests are used. To ensure that the computational complexity of test compaction is not increased by a fault model with a large number of faults, or faults with complex behaviors, the added fault model is required to have the same characteristics as the transition fault model. A type of transition fault called unspecified transition fault satisfies these requirements. The article describes a test compaction procedure for transition faults that incorporates unspecified transition faults, and presents experimental results for benchmark circuits to demonstrate the levels of test compaction and fault coverage that can be achieved.

A Simple and Fast Solution for Fault Simulation Using Approximate Parallel Critical Path Tracing

Due to the growing complexity of today’s digital circuits, the speed of fault simulation has become increasingly important. Although critical path tracing (CPT) is faster than conventional methods, it is not fast enough for fault simulation of complex circuits with a large number of faults and tests. Exact stem analysis is the most important obstacle in accelerating the CPT method. The simplification of stem analysis eliminates time-consuming computations and makes the CPT method more parallelizable. An approximate and bit-parallel CPT algorithm is proposed for ultrafast fault simulation for both stuck-at-fault (SAF) and transition delay fault (TDF) models. Time linearity, speedup, and accuracy of the proposed algorithm are examined and evaluated using ISCAS85, ISCAS89, and ITC99 benchmark circuits. In order to assess the accuracy, the false-positive and false-negative detection of faults are counted for each benchmark circuit. The experimental results reveal considerable speedup as well as acceptable accuracy of the proposed approach in comparison with the traditional methods and commercial fault simulators.

Fault Awareness for Memory BIST Architecture Shaped by Multidimensional Prediction Mechanism

This paper introduces a novel solution for building fault aware memory built-in self-test infrastructure based on rules of fault periodicity and regularity in memories and test algorithms. These periodicity and regularity rules are described via special internal structures named fault periodicity table (FPT) and test algorithm template (TAT). Three dimensions of evolution are considered as inputs for forming the mentioned structures: memory cells, multidimensional memory circuits, and memory systems for systems-on-chip where memories are distributed in different subchips. Each column of FPT corresponds to a fault nature which can be associated with a variety of different test mechanisms while each row of FPT corresponds to a fault family determined by the complexity of fault sensitization. FPT allows considering any large number of faults in one table while TAT allows constructing test algorithms without using test algorithm generation tools. Experimental results of the solution applied to both Planar-based (90/65/45/28 nm) and FinFET-based (16/10/7 nm) memory technologies are adduced also in this paper.

HYDROGEOCHEMICAL CONDITIONS OF THE MESOZOIC HYDROGEOLOGICAL BASIN IN THE TERRITORY OF THE YARUDEY OIL AND GAS CONDENSATE FIELD

Hydrogeochemical conditions of the Yarudey oil and gas condensate field are largely determined by its position within the elysion lithostatic water pressure system and the presence of a large number of faults in the base plate. In the article we explore the main features of the Neocomian and the Jurassic hydrogeological complexes of the field. Underground waters of the Mesozoic hydrogeological basin are characterized by chloride sodium ion-salt composition. They belong to the hydrocarbonate sodium type according to V. A. Sulin’s classification, mineralization is 7,0 g/l in the Neocomian complex and is 11,1 g/l in the Jurassic complex. The existence of complex hydrogeochemical conditions is confirmed by the nature of the change in the genetic sodiumchlorine coefficient (up to 1,4) and boron-bromine coefficients (up to 0,49).

Computing Fault-Containment Times of Self-Stabilizing Algorithms Using Lumped Markov Chains

The analysis of self-stabilizing algorithms is often limited to the worst case stabilization time starting from an arbitrary state, i.e., a state resulting from a sequence of faults. Considering the fact that these algorithms are intended to provide fault tolerance in the long run, this is not the most relevant metric. A common situation is that a running system is an a legitimate state when hit by a single fault. This event has a much higher probability than multiple concurrent faults. Therefore, the worst case time to recover from a single fault is more relevant than the recovery time from a large number of faults. This paper presents techniques to derive upper bounds for the mean time to recover from a single fault for self-stabilizing algorithms based on Markov chains in combination with lumping. To illustrate the applicability of the techniques they are applied to a new self-stabilizing coloring algorithm.

Genetic mechanisms of coalbed methane in typical districts from Huaibei Coalfield, Eastern China

ABSTRACTTaking insight into genetic mechanisms of coalbed methane (CBM) can provide an effective approach for evaluating the value of CBM resources. In this study, the geo-temperature and the thermal subsidence history were used to investigate the effect of the present geothermal field characteristic on the genetic mechanisms of CBM at the Huaibei Coalfield. The results showed that the Permian coal strata in the study areas had a relatively low geo-temperature (< 50°C), high vitrinite reflectance (Ro,max; 0.75%-1.2%) and a coal rank typical of intermediate-high metamorphic bituminous. Comprehensive analyses of the characteristics of the present geothermal field indicate that the CBM at the Huaibei Coalfield are dominated by secondary biogenic gases. Furthermore, the genetic mechanism towards CBM was further proposed based on the tectonic evolution history: (1) Tectonic thrusting contributed to Ro,max values ranging from 0.5% to 3.0%, with maximum geo-temperatures of 140–180°C, which resulted in the generation of thermogenic CBM. (2) An extensional regime contributed to gradual uplift of the Permian coal-bearing strata, with the gradual escape of CBM at burial depths greater than 700m. (3) A large number of faults and hydrodynamic environments greatly promoted the microbial degradation of the early thermogenic gases, resulting in generation of secondary biogenic gases.

The diagenetic and tectonic significance of hydrocarbon accumulation in the southern Junggar Basin, NW China

The Jurassic petroleum system plays an increasingly important role in petroleum explorations in the southern Junggar Basin. To assess the hydrocarbon distribution and the accumulation history of the Jurassic reservoirs in this area, we carried out reservoir petrographic, fluorescence spectroscopic, and fluid inclusion petrographic analyses on the core and cutting samples from the QQ‐2 well in the Qigu Anticline. The oil accumulation has the partiality for high‐quality sandstone reservoirs that have the high porosity and permeability with values of 14–18% and (1–450) × 10−2 μm2, respectively, in the Middle Jurassic Toutunhe Formation (J2t) reservoirs. The pores are big with average diameters of 60–100 μm, and the pore throats are wide with values of 3.45–6.92 μm in the oil reservoirs. The intergranular pores survive thanks to the poor compaction and the poor cementation, and the dissolved and mould pores develop attributed to the strong dissolution in the oil reservoirs. Two episodes of oil charging and one episode of gas invasion were identified in the Middle Jurassic reservoirs in the southern Junggar Basin. The low‐maturity paleo‐oil charged the sandstone reservoirs at about 35 Ma when the paleo‐traps took shape during the Cretaceous–Eocene. A large number of faults and anticlinal traps was developed in the southern Junggar Basin at about 7 Ma, caused by the reactivation of the Tianshan Mountains in the late Cenozoic. Simultaneously, the leakage of the paleo‐oil, the accumulation of late oil, and the gas invasion all took place. Fault activities led to the leakage of paleo‐oil and helped the oil and gas accumulate in the Middle Jurassic reservoirs in the anticlinal trap shaping at about 7–8 Ma in the southern Junggar Basin.