Hasil untuk "Dynamic and structural geology"

Diego Melgar

Tsunami hazard assessments often assume that co-seismic crustal deformation occurs instantaneously, particularly in probabilistic tsunami hazard analyses (PTHA). However, this simplification neglects the kinematics of rupture propagation, which may influence tsunami amplitudes at distant sites. Building on previous work, this study investigates the impact of rupture kinematics – specifically rupture directivity and duration – on far-field tsunami amplitudes. Using 2600 synthetic megathrust earthquake scenarios along a 1500 km segment of the Alaskan subduction zone, I model tsunami propagation with both instantaneous and time-dependent rupture assumptions. Simulations reveal that source kinematics can significantly rotate the tsunami radiation pattern and increase peak amplitudes by over 30% at far-field sites for large (Mw>9.0) events. When incorporated into a full PTHA framework, the inclusion of rupture kinematics systematically increases hazard estimates at most coastal locations. These results suggest that neglecting rupture kinematics may lead to underestimation of far-field tsunami hazard, particularly for large, unilateral ruptures. I recommend the formal inclusion of rupture kinematics in both deterministic scenario design and probabilistic hazard frameworks to better capture the full range of potential tsunami impacts.

Neil Collings, Martin R. Parker

This paper outlines a simple theoretical argument for the possibility of a quantum linear Voigt effect at low temperatures in certain media in the optical regime. An unlikely starting point for the ensuing argument arises out of a long-established hydrodynamic Lorentz field-modified classical dispersion theory whose Voigt component of the optical conductivity, when subjected to the Uncertainty Principle, results in a modified form in the quantum region. In contrast to its classical, second-order counterpart, this quantum Voigt conductivity is shown to have a (modular) linear field dependence.

Bragin, Ivan V., Chelnokov, Georgy A., Lavrushin, Vasily Yu. et al.

We present the results of a comprehensive study of high PCO2 mineral waters of Primorsky Krai, aimed at identifying their genesis and conditions of formation. For the first time, a joint analysis of the chemical and micro component composition of water, the gas phase (CO2, N2, CH4, H2, He, and Ar), and stable isotopes of oxygen and hydrogen (δ18O, δ2H) was carried out for a number of poorly studied springs, gained either during this study or previously by our group. Three genetic groups of waters were identified based on hydrogeochemical data: 1) Ca-HCO3 type waters (Bolshoy Klyuch and Fabrichny springs) formed in terrigenous strata; 2) deep silicate-type waters (Pokrovsky and Glukhovka springs) associated with interaction with crystalline basement rocks and enriched with lithium, rubidium, and barium; 3) acidic waters of the sulfide oxidation zone (Nerobinsky spring), which are indicators of ore mineralization; 4) mixed-type waters showing the features of the three types described above. Gas-geochemical studies confirmed the predominance of CO2 of mantle genesis ( >96.9 vol.%) and the redox environment. Unique anomalies were identified, such as a high methane content (up to 2.26 vol.%) in the Pokrovsky spring, indicating possible thermogenic processes. The isotopic composition of the waters (δ18O from –14.71 to –8.70 ‰, δ2H from –103.79 to –60.28 ‰) clearly indicates their meteoric origin from cold climate precipitation, while the shift relative to the global meteor line indicates intensive isotope exchange in the water rock–gas system. The results of the study are of fundamental importance for understanding the fluid dynamics of the Sikhote-Alin subsurface and can be applied for expanding the mineral resource base, developing balneology, and conducting geological prospecting in the Primorsky region.

C. E. Iles, B. H. Samset, M. T. Lund

<p>The climates of the polar and mid-latitude regions are linked through teleconnections. The regional details of these relationships, and how they may change with global warming, are however still uncertain. Using two large ensembles of coupled climate model simulations (CESM2, ACCESS-ESM1.5) and a composite analysis, we investigate the statistical relationships between sea ice variability and atmospheric circulation patterns, and how they evolve with sea ice retreat for both poles, including sensitivity to sea ice region in the Arctic. We find that relationships between sea ice amount and sea level pressure (SLP), the North Atlantic jet stream, and surface air temperature (SAT), depend on the region where sea ice varies. For instance, the North Atlantic jet resides further south when sea ice is low in the Labrador Sea, but is located further north and/or is weaker for low Okhotsk sea ice and is stronger and displaced northwards for low Chukchi-Bering sea ice. We also investigate the circulation patterns associated with changes in Antarctic sea ice. For the Arctic, circulation patterns tend to persist with global warming, until around 3 or 4 °C, when the ice edge has retreated substantially. In the Antarctic, patterns are sensitive to warming also at lower global warming levels for some seasons and variables, but are otherwise often persistent across warming levels. Lagged analysis suggests that the concurrent relationships mostly reflect the atmospheric conditions contributing to low sea ice, with weaker or altered patterns when sea ice leads. Our results emphasize the importance of regional heterogeneity, and on using large ensembles or other statistically rich datasets, for assessing the interlinkages between polar climate change and mid-latitude weather patterns, today and in a warmer climate. The overall persistence of teleconnection patterns between sea ice change and atmospheric circulation with global warming is encouraging, as it indicates that the main conclusions from current literature will be applicable also in a future, warmer world with less sea ice.</p>

Miao Zhang, Lianxing Wen

This study examines event location and source discrimination for the May 12, 2010 possible nuclear event in North Korea, using seismic data recorded in the Dongbei Broadband Seismic Network in China. Using highly similar Pg waveforms between the events, we locate the event within 2 ​km of the 2009 nuclear test site. For event classification, we first build a group of reference earthquakes and explosions through a machine-learning phase picker and an event association/location process, with open-access satellite image verification; we then classify the event based on the Pg/Lg spectral ratios and Pg waveform similarity comparisons with past nuclear tests. The event is classified as a small explosion reaffirming the findings of Zhang and Wen (2015a). Along with independent scientific evidence from radionuclide studies and infrasound signal analysis, the May 12, 2010 event can be reasonably attributed to a low-yield nuclear test. Our study shows that explosion discriminants are dependent on event magnitudes and seismic noises, and vary from station to station. Accordingly, event classification should be performed on a station-by-station basis. The approach presented here is useful for seismic monitoring of low-yield nuclear tests.

Mengjie Yang, Shenghua Cui, Tao Jiang

Earthquake-induced landslides have always been a hot research topic in the field of geosciences. However, there have been few bibliometric analyses on this topic. To systematically understand the research status, this study is based on bibliometrics and extensively uses visualization analysis techniques. It combines quantitative and qualitative methods to conduct an in-depth analysis of 5 016 papers collected from the Web of Science (www.webofscience.com). The results revealed that: ①The number of papers on earthquake-induced landslides is steadily increasing, and is expected to continue to rise. ②Countries prone to frequent earthquakes have made significant contributions to the research on earthquake-induced landslides, and the frequent and effective cooperation among these countries has had a very positive impact on promoting landslide study. ③ Research on earthquake-induced landslides is no longer limited to the field of geology, and the future direction is to integrate knowledge and technical methods from multiple disciplines. In the research methods of earthquake-induced landslides, there is a gradual shift from ''experience, theory'' to ''data-driven''. This study can provide researchers in this field with information on the core research forces, evolving hot topics, and future development trends of earthquake-induced landslides.

Franca Buelow, Jade Gibson, Nina Vargoczky et al.

Diversity of thought is vital for research, yet different knowledge systems and disciplines are often viewed as incompatible. Bioprotection Aotearoa (BA), a National Centre of Research Excellence, leads research to protect ecosystems in Aotearoa New Zealand and the Pacific from biological threats such as pathogens, pests and weeds. It centres itself around a research framework led by Indigenous values. We examine whether and how BA's placement of Indigenous knowledge at its core and its efforts to inspire trans- and interdisciplinary research promotes and sustains a pluriverse perspective. Through thematic analysis of expert interviews, we identify key factors influencing pluriversality and reflect on how these influence diversity, equity and inclusion. Interviewees outline that placing Indigenous and scientific knowledge systems on an equal footing improves diversity practices overall. Essential drivers that encourage pluralism of thought and engagement with multiple knowledges and practices are identified as: intentional community-building efforts, clear operational guidelines and deliberate alignment of research efforts towards a synergy of Indigenous knowledge with Western perspectives. Interviewees point to barriers such as time constraints, limited resources, disciplinary silos and a bias toward the status quo. Our case study highlights the importance of leadership and organizational guidance in embracing a pluriverse approach.

C. Hibert, F. Noël, F. Noël et al.

<p>Understanding the dynamics of slope instabilities is critical to mitigate the associated hazards, but their direct observation is often difficult due to their remote locations and their spontaneous nature. Seismology allows us to get unique information on these events, including on their dynamics. However, the link between the properties of these events (mass and kinematics) and the seismic signals generated is still poorly understood. We conducted a controlled rockfall experiment in the Riou Bourdoux torrent (southern French Alps) to try to better decipher those links. We deployed a dense seismic network and inferred the dynamics of the block from the reconstruction of the 3D trajectory from terrestrial and airborne high-resolution stereophotogrammetry. We propose a new approach based on machine learning to predict the mass and the velocity of each block. Our results show that we can predict those quantities with average errors of approximately 10 % for the velocity and 25 % for the mass. These accuracies are as good as or better than those obtained by other approaches, but our approach has the advantage in that it does not require the source to be localised, nor does it require a high-resolution velocity model or a strong assumption on the seismic wave attenuation model. Finally, the machine learning approach allows us to explore more widely the correlations between the features of the seismic signal generated by the rockfalls and their physical properties, and it might eventually lead to better constraints on the physical models in the future.</p>

N. Wunderling, N. Wunderling, N. Wunderling et al.

<p>Climate tipping elements are large-scale subsystems of the Earth that may transgress critical thresholds (tipping points) under ongoing global warming, with substantial impacts on the biosphere and human societies. Frequently studied examples of such tipping elements include the Greenland Ice Sheet, the Atlantic Meridional Overturning Circulation (AMOC), permafrost, monsoon systems, and the Amazon rainforest. While recent scientific efforts have improved our knowledge about individual tipping elements, the interactions between them are less well understood. Also, the potential of individual tipping events to induce additional tipping elsewhere or stabilize other tipping elements is largely unknown. Here, we map out the current state of the literature on the interactions between climate tipping elements and review the influences between them. To do so, we gathered evidence from model simulations, observations, and conceptual understanding, as well as examples of paleoclimate reconstructions where multi-component or spatially propagating transitions were potentially at play. While uncertainties are large, we find indications that many of the interactions between tipping elements are destabilizing. Therefore, we conclude that tipping elements should not only be studied in isolation, but also more emphasis has to be put on potential interactions. This means that tipping cascades cannot be ruled out on centennial to millennial timescales at global warming levels between 1.5 and 2.0 <span class="inline-formula">^∘</span>C or on shorter timescales if global warming surpassed 2.0 <span class="inline-formula">^∘</span>C. At these higher levels of global warming, tipping cascades may then include fast tipping elements such as the AMOC or the Amazon rainforest. To address crucial knowledge gaps in tipping element interactions, we propose four strategies combining observation-based approaches, Earth system modeling expertise, computational advances, and expert knowledge.</p>

Jianzhong Li, X. Tao, B. Bai et al.

Abstract By analyzing the structural background, petroleum geological conditions, and typical regional (paleo) oil and gas reservoirs in marine ultra-deep oil and gas regions in China, this paper reveals the evolution processes of the marine ultra-deep oil and gas reservoirs and the key controlling factors of accumulation. The marine ultra-deep oil and gas resources in China are buried at depth of greater than 6000 m, and are mainly distributed in the Precambrian and Lower Paleozoic strata in the Sichuan, Tarim and Ordos cratonic basins. The development of marine ultra-deep source rocks in China is controlled by cratonic rifts and cratonic depressions with the background of global supercontinent breakup-convergence cycles. The source rocks in Sichuan Basin have the most developed strata, followed by Tarim Basin, and the development strata and scale of Ordos Basin needs to be further confirmed. The marine ultra-deep reservoir in China is dominated by carbonate rocks, and the reservoir performance is controlled by high-energy sedimentary environment in the early stage, superimposed corrosion and fracture in the later stage. The regional caprocks are dominated by gypsum salt rocks, shale, and tight carbonate rock. The ultra-deep oil and gas fields in China have generally experienced two stages of oil-reservoir forming, cracking (or partial cracking) of paleo-oil reservoirs, and late finalization of cracked gas (or highly mature to over mature oil and gas). The oil and gas accumulation is controlled by static and dynamic geological elements jointly. Major hydrocarbon generation center, high quality and large-scale reservoir resulted from karstification of high energy facies belt, thick gypsum rock or shale caprock, and stable trapping and preservation conditions are the key factors for accumulation of ultra-deep oil and gas. We propose three favorable exploration directions, i.e. the areas around intracratonic rift and intracratonic depression, and craton margin.

Jinming Zhang, Xiaowei Hou, Guanqun Zhou et al.

Dong Li, Yinling Guo, S. Peng et al.

Frequency band limitation of seismic data limits the resolution of full waveform inversion (FWI) results. Additionally, the high computational cost seriously affects the practical application of FWI. To alleviate these concerns, an FWI method based on super-resolution (SR-FWI) is proposed to improve prediction efficiency and accuracy of the reservoir parameters. A channel attention mechanism is introduced for multi-frequency characteristics of the model images. A constrained residual channel attention network (CRCAN) is built for super-resolution (SR) by adding structural constraints to the loss function of a deep learning network. A total of 65,000 sets of geological models and natural images constitute the network training data, 90% of which are used for training with the rest used for testing. The iterative calculation for FWI is time-consuming, hence SR is applied to the iterative process to reduce the number of iterations and accelerate the model update. Low-resolution images along with the synthetic and field data are used for evaluation of the CRCAN and SR-FWI algorithms, respectively. The test results show that CRCAN can effectively improve the image resolution, while SR-FWI is beneficial due to its high efficiency and precision, especially in predicting the stratum edge and small-scale anomalies. Therefore, SR-FWI is a powerful means of the reservoir static and dynamic detection, and can provide high-resolution information for projects, such as resource development and CO2 storage.

A. Kozyrev, I. Semenova, S. Zhukova et al.

Large-scale mining operations over 90 years at the Khibiny apatite-nepheline deposits that are characterized with the conspicuous gravity-tectonic type of the stress-strain state have transformed the initial stress field of the rock massif, which has led to the recurrent occurrence of rockbursts. This problem retains its relevance due to constant increasing intensity of mining operations at the apatite mines during the last two decades and complicated mining, geological and geomechanical conditions. Accordingly, the dynamic rock pressure is increasing. We have retrospectively analyzed data on the manifestations of geodynamic events in the Khibiny rockburst-hazardous deposits and determined a set of factors that influence the changes in seismic behavior and localization of hazardous zones in complicated mining and engineering systems. We have systematized the data of long-term observations on dynamic rock pressure manifestations at the Khibiny apatite mines, taking into account the seismicity parameters, the scale of mine damage, the mining-induced stress fields, and geological and geomechanical features of the rock massif at specific time points. A structural scheme has been developed and ranking of factors has been carried out, considering the time of impact on the rock massif.

Miltiadis Kontogeorgos, Clemente Fuggini

The current study investigates the capacity of the proposed meta-material layout for the blast protection of above-ground steel pipes against explosions. The philosophy of the meta-material layout’s design is described adequately, and the 1D periodic structures’ theory is adopted for the analytical prediction of the layout’s band-gaps. The special characteristics of the blast loading are explained, and specific time-related parameters are calculated. The layout is tested numerically for nine explosion scenarios of various magnitude via the finite element program ABAQUS, and the CONWEP model is selected for the simulation of the explosions. The results demonstrate a significant reduction in the maximum displacements developed on the pipe’s spring line and crown within a blast loading. This study composes an extension of the author’s previous research on buried steel pipes and surface explosion, advancing now the applicability of the meta-material layouts for the cases of above-ground steel pipes towards explosions and blast hazards. The outer goal is the investigation and the further spreading of the beneficial exploitation of meta-materials concepts for the scope of the pipelines’ effective blast protection, readdressing that this way is a major hazard for this type of structure and a gap in the current literature.

Yuhang Chu, Rui Li, Xiaozhang Li

Most of the deep-water bridges in Chinese reservoirs are concentrated on rivers in the southwest region. The unique structural characteristics of arch bridges are more in line with the geological topography requirements of deep reservoir areas, making them the bridge type of choice for bridges in deep reservoir areas. While the southwest region is an earthquake-prone area, in order to study the safety of arch bridges across deep water in the reservoir area, it is necessary to analyze the effect of water under seismic behavior on the box section arch ring and explore the effect of arch inundation depth on the dynamic response of arch bridges in the reservoir area. In this study, the effect of fluid-solid coupling is considered, the modified Morison equation is used to calculate the hydrodynamic pressure, and the effect of arch bridge inundation depth on the dynamic response is analyzed based on the Midas/civil finite element model of the arch bridge in the Yunnan reservoir area. The results show that the seismic response of the arch bridge across the reservoir is greatly influenced by the submergence depth of the arch bridge due to the fluid-solid coupling effect, and the influence of the hydrodynamic pressure on the longitudinal moment (My) and transverse moment (Mz) of the arch bridge increases with the increase of the submergence depth. There is a threshold value of the submergence depth. When the submergence depth is less than the threshold, the effect of fluid-solid coupling is negligible, and when the submergence depth is greater than the threshold, the fluid-solid coupling effect is significant. The thresholds for different parts of the main arch ring are different. The most unfavorable water depth in different parts of the main arch ring is not necessarily the water depth when the arch ring is completely submerged. Based on this result, for reservoir arch bridges in high intensity areas, it is recommended that the inundation depth of arch bridges crossing deep water reservoirs should be h/f less than or equal to 5/8 f.

Haigang Qu, Dianrui Mu, Zhong Nie et al.

Numerous researchers of soil creep behavior adopt stepwise loading (SL) rather than respective loading (RL) to perform the triaxial creep tests. However, a complete continuous strain–time curve of SL needs to be converted into assumed curve clusters supposing obtained under RL before the deformation data are used to develop creep constitutive models. Classical methods realize the conversion mainly by focusing on the creep deformation parts and classifying them into linear and nonlinear compositions. Mostly, the linear parts are simply superposed while the nonlinear parts are complex to consider and so are neglected. Moreover, classical methods are not sufficiently valid to eliminate the stress history effect on the conversion. Here, a new method is proposed to achieve the conversion without neglecting the stress history effect. The method rebuilds the triaxial creep test mathematically and physically, adhering to the revising of energy. The method treats the tested deformation in its entirety, instead of distinguishing it into elastic, visco-elastic, plastic and creep (linear and nonlinear) deformation to convert respectively. The comparison among actual measured SL and RL strain–time curves and the curves converted by the new method proves the stress history effect should not be neglected. The higher the vertical load level, the larger the discrepancy between the RL and SL strain–time curve, and the disparity becomes larger with time. The new method highlights the necessity of considering the stress history effect in analysis and design for higher accuracy. The comparisons illustrate the conversion method at least produces more satisfactory results for clayey soil. Primarily examined, at the later stages of loading, the disparity in strain between the converted RL and measured RL decreases by 52.5%~53.5% compared with strain between the measured SL and measured RL.

Ortwin Renn, Richard Gloaguen, Christina Benighaus et al.

Drastic measures are required to meet the standards of the Paris Agreement and limit the increase of global average temperatures well below 2°C compared to pre-industrial levels. Mining activities are typically considered as unsustainable but, at the same time, metals such as cobalt and lithium are essential to sustain the energy transition. Several sustainability goals defined by the United Nations (UN) require large quantities of raw materials. Exploration and extractives activities are required in order to contribute to meeting sustainability standards. Future sourcing of metals will need to implement procedures that go well beyond current ecological, economic, and social requirements and practices. In this paper we assess the usual sustainability criteria and how they apply to the extractives sector. Sustainability can only be achieved if one accepts that the natural capital can be substituted by other forms of capital (so called weak concept of sustainability). Sourcing the raw materials increasingly demanded by our societies will need transparent and inclusive stakeholder participation as well as a holistic understanding of the impact of extractives activities to reach this weak sustainability status. Our analysis shows that the sustainability of mining cannot be reached without harmonized political instruments and investment policies that take the three pillars of environmental, economic, and social sustainability as a major priority.

F. Wellmann, S. Virgo, D. Escallon et al.

Augmented Reality Sandboxes are a valuable tool for science outreach and teaching due to their intuitive and haptic interaction-enhancing operation. Most of the common AR-Sandboxes are limited to the visualization of topography with contour lines and colours, as well as water simulations on the digital terrain surface. However, many geologists will intuitively want to use this system to visualize geology and literally &#8220;dig deeper&#8221;, to see how geological units change below the surface. In fact, if we consider the AR-Sandbox in its bare essential, as a 2.5-D haptic dynamic interface to a 3-D or 4-D system, then many more potential applications come to mind: from geological education and outreach, over the representation of geophysical fields, to dynamic simulations.&#160;In this contribution, we present an open-source implementation of an AR-Sandbox system with an interface in Python, which enables simple access to this tool. This implementation allows for creative and novel applications in geosciences education and outreach in general. With a link to a 3-D geomodelling system, we show how we can display geologic subsurface information such as the outcropping lithology, creating an interactive geological map for structural geology classes. The relations of subsurface structures, topography and outcrop, can be explored in a playful and comprehensible way. Additional examples are geoelectric fields and the propagation of seismic waves, as well as simulations of landslides at the surface. We further extended the functionality with an implementation of ArUco marker detection to enable interactive cross-section generation, among other examples. Many other implementations can be envisaged for the use of this system, and we look forward to creative contributions to geoscience education.

D. Kulikowski, K. Amrouch, K. Pokalai et al.

Abstract This review focuses on integrating old literature with present-day models to provide a modern summary of Australia’s largest onshore hydrocarbon province, the Cooper–Eromanga Basin, with a focus on structural geology and geophysics. A rapid rise in cutting-edge research has been facilitated by hydrocarbon companies transitioning to technically more challenging plays and feasibility studies assessing the carbon capture and storage potential of the basin. The purpose of this review is to provide researchers and new and existing operating companies with an integrated summary of recent research and the fundamentals of the structurally complex basin with the aim of ensuring that the hydrocarbon potential can be effectively explored and appropriately developed, and that the carbon capture and storage potential of the basin is appropriately evaluated. A modern tectonostratigraphic evolution model is presented alongside the stress regime, orientation and magnitude of the six events that have affected the province (N–S Carboniferous Alice Springs Orogeny; SE–NW mid-Permian event; NE–SW late Permian Daralingie event; E–W Triassic Hunter–Bowen Event; E–W Late Cretaceous event; N–S Paleogene event). Integration of complete paleo-stress tensors with geomechanical models has constrained the dynamic reactivation (shear and tensile) of faults through time and space to find that since the critical time (90 Ma), N–S- and E–W-striking high-angle (50–70°) faults were most likely facilitating hydrocarbon migration. These form the major topics of the review as they can significantly impact exploration and development success and effective carbon capture and storage. In addition, the four-dimensional distribution of natural fractures away from the wellbore, seismic time-to-depth conversion methods and accuracies, petroleum systems elements and processes, current and future exploration programs, common hydraulic fracturing and well surveillance programs, and recommendations for future research are also discussed. The methodologies, cutting-edge research and novel approaches presented here form a framework that can be applied to other hydrocarbon provinces around the world, while also providing a knowledge platform for this highly prospective hydrocarbon and potential carbon storage province. KEY POINTS Comprehensive modern literature review of the Cooper–Eromanga Basin. Integration of geophysics, geology and reservoir engineering to form a holistic synthesis of Australia’s largest onshore hydrocarbon province. Insights into the interaction between hydrocarbon migration and basin evolution.

Feiyan Li, Linjian Wang, Yingxiong Wu

Long-period structures (e.g. Isolated structures) tend to produce pseudo-resonance with low frequency components of long-period ground motions, resulting in the increase in damage. Stiffness mutation occurs due to the set-back in the upper body of the large chassis structure. In the parts with stiffness mutation, the torsion effect caused by the tower is far greater than that of the chassis itself. In this study, a total of 273 ground motions are collected and then filtered into four types, including the near-field ordinary, near-field pulse, far-field ordinary, and far-field harmonic. An 8-degree (0.2 g) fortified large chassis base-isolated structure is established. Furthermore, ETABS program software is used to conduct nonlinear time history analysis on the isolation and seismic model under bi-directional earthquake ground motions. The comparison results show that the seismic isolation effect of the base-isolated structure under long-period ground motions is worse than that associated with ordinary ground motions when the seismic response reduction rate of the large base floor significantly decreases compared with that of the tower. When the inter-story displacement angle and the displacement of isolation layer of the chassis exceeds the limit of Code for Seismic Design of Buildings (GB 50011-2010), it is recommended to adopt composite seismic isolation technology or add limit devices. Under the condition of long-period ground motions, the base-isolated structure reduces the lateral-torsional coupling effect of the large chassis structure, while the torsion response of large chassis’ top layer increases. Under long-period ground motions with the same acceleration peak, the response of the base-isolated structure increases much more than that of the seismic structure and the consideration of this impact is suggested to be added to the Code.