Heat Flow Studies Research Articles

Thermal rectification in segmented Frenkel–Kontorova lattices with asymmetric next-nearest-neighbor interactions

In this work, we conduct an extensive study of the asymmetric heat flow, i.e. thermal rectification, present in the two-segment Frenkel Kontorova model with both nearest-neighbor (NN) and next-nearest-neighbor (NNN) interactions. We have considered systems with both high and low asymmetry and determined that, in the weak-coupling limit, thermal rectification is larger when NNN interactions are relevant. The behavior of the heat fluxes as a function of the coupling strength between the two segments is largely consistent with a well-defined rectification for larger system sizes. The local heat fluxes present a very different behavior for systems with high and low asymmetry. The results of this work may help in the design of molecular bridges, which have recently been shown to be able to function as thermal rectification devices.

Study of Heat Flow at Substrate during Sputtering of Copper-Titanium Sandwich Target.

The purpose of this work is to study the kinetics of the heat flow heating the substrate, which is generated by a two-layer sandwich magnetron target when sputtered in argon. Its novelty resides in the application of the COMSOL Multiphysics to study the kinetics of thermal processes during sputtering of a target of the new type. The analysis was performed for a sandwich target with internal copper and external titanium plates when the discharge power varied in the range of 400-1200 W. The heating of the external target plate is described by a two-dimensional homogeneous Fourier equation. The solution to the equation reveals how the kinetics of the external plate's surface temperature distribution depends on the discharge power. To study the heat flow heating the substrate, the external plate is presented in the form of an additive set of small-sized surface heat sources. Previously unknown features of the thermal process are established. It is shown that numerical modeling adequately describes the experimental results.

New heat flow data on the South Balearic margin: Evidence of regional fluid circulation system

Crustal heat loss processes in contexts other than mid-ocean ridge flanks are still poorly understood and described in the literature. In this work, we present 54 new surface heat flow measurements recorded along the South Balearic margin and across the Hannibal High area, in the Western Mediterranean Sea, away from spreading centres. The South Balearic margin is a narrow continental margin expressed on the seabed topography by the steep Emile Baudot Escarpment while the Hannibal High area, further south, is a presumed volcanic oceanic crust zone. Recent heat flow studies pointed out the presence of strong local thermal anomalies, imprinted in regional deep basin heat flow increasing from the eastern to the western Algerian basins (70–90 to 100–130 mW/m2). The new data in this study confirm local anomalies around the Emile Baudot seamounts and allow the delineation of some low and high heat zones. We show that (1) a correlation exists between the heat flow variability and the sedimentary cover thickness, and (2) the most pronounced anomaly is a low heat flow zone (30 km wide) observed in the mid-slope South Formentera basin, close to the basaltic basement of the Los Martines volcano. The correlation of heat flow with sedimentary thickness, the lateral extent of the heat flow anomalies, the flux peak magnitudes, and the co-existence of both low and high anomalies suggest the presence of an active fluid circulation system. Based on the arrangement of the anomalies in relation to the basaltic basement seamounts, we consider a syphon-type circulation system in the Formentera basin. Reduced heat flow suggests a recharge zone close to the Los Martines seamount, while local high heat flow located close to a smaller seamount could be a potential zone of fluid discharge. Although different buoyancy-driven circulations could occur in the South Balearic margin, we believe that a syphon-type hydrothermal circulation along permeable basaltic mounds and sealed basement conduits, similar to the off-axis oceanic crust, is best developed in the young marginal basin of the South Balearic margin.

A study of heat and mass transfer flow of a variable viscosity couple stress fluid between inclined plates

In this paper, the Poiseuille flow of non-isothermal couple stress fluid of Reynolds model between two heated parallel inclined plates has been studied. The strongly nonlinear coupled ordinary differential equations have been investigated using the Asymptotic Homotopy Perturbation method (AHPM) and the Optimal Homotopy Asymptotic Method with DJ Polynomials (OHAM-DJ). Employing both these techniques, the approximate solutions for velocity profile, temperature distributions, shear stress, average velocity and volumetric flow rate have been achieved. The results obtained using both these methods are in the form of infinite series, hence the results can be obtained easily. Comparison of various results, obtained through these methods, is carried out. Here, it is worth to mention that the results gained by both these approaches are in excellent resemblance. The effect of different parameters on the flow problem has been studied numerically as well as presented graphically.

Improving the heat transfer characteristics of miniature two-phase thermosyphons with nanofluids based on Ukrainian natural alumosilicates

In order to improve the heat transfer characteristics of miniature thermosyphons, a study of the processes of heat transfer by them using water and nanofluids as heat carriers was carried out. A water mixture based on nanoparticles of Ukrainian natural aluminosilicate - attapulgite with the addition of 0.1 % carbon nanotubes was used as nanofluids. The data of the study of the maximum heat flow and the minimum thermal resistance of copper thermosyphons with an internal diameter of 5 mm and a length of 700 mm are presented. Orientation of thermosyphons in space: vertical. The length of the heating zone varied from 50 mm to 200 mm, with the same amount of heat-carrier. The fill factor varied from 0.44 to 1.93. A comparison was performed of the heat transfer capabilities of thermosyphons with water and with a nanofluid with a mass concentration of 0.5 %. It has been shown that nanofluid thermosyphons transmit 53 % more heat flow compared to water, and thermal resistances are reduced by 25 %. The influence of the concentration of nanoparticles on the heat transfer characteristics of thermosyphons is shown. Nanofluids with concentrations (0.1 %, 0.5 %, 0.7 %) showed the same level of thermal resistances, with an increase in maximum heat flows compared to distilled water. Thus, when compared with the lowest concentration (0.1 %), the use of 0.5 % nanofluid gives an advantage of up to 40 %, and 0.7 % – an advantage of up to 51 %. This is explained by the appearance of a specific porous structure of anisometric nanoparticles on the heating surface, which contributes to the appearance of additional centers of vaporization during boiling and improves the heat transfer characteristics of thermosyphons. Thus, the use of such thermosyphons with nanofluids when cooling elements of electronic equipment could improve their functional characteristics

Heat and mass transfer effects on fluid past an exponentially accelerated vertical plate due to time‐fractional MHD‐free convection

AbstractThis article focuses on the study of heat and mass transfer (HMT) fluid flow over an exponentially accelerated vertical plate, which is subjected to an applied magnetic field and viscous dissipation. The research has applications in various manufacturing processes such as wire/fiber drawing, hot rolling, continuous casting, and hot extrusion, where heat transfer to the ambient medium and the hot moving material are of utmost importance. The findings could also be relevant to aerospace engineering applications. The study investigates the time‐fractional natural convection phenomenon and utilizes conservation laws to derive the flow guiding equations, which are then made nondimensional. Finite difference discretization is utilized to solve the dimensionless equations implicitly. Then the flow simulation results such as concentration, temperature, and velocity profiles are discussed based on the variation in parameters such as Prandtl number (), thermal/mass Grashof number (), Eckert number (), magnetic parameter (), time‐fractional order (), and Schmidt number . Also, the HMT rate is depicted using the Nusselt number and skin friction plots. It is noted that HMT increases when increases and decreases. The change in time‐fractional order affects the velocity profiles adjacent to the wall and is more significant in the case of lower values of the Prandtl number.

Predicting Marine In Situ Heat Flow Using a Geospatial Machine Learning Conformal Prediction

AbstractHeat flow measurements over the past decades have drastically increased in number. However, even with vast increases in measurements, large geospatial gaps exist, most notably across Earth's oceans. As marine heat flow data acquisition can be tedious, time consuming, and ultimately expensive, new methods have arisen in an attempt to quantify heat flow across the seafloor using empirical proxies. The goal herein is to obtain a high quality, fully data‐driven, global estimate of marine in situ heat flow with calculated uncertainty. We present a heat flow analysis for Earth's marine environment using a geospatial machine learning algorithm (MLA) utilizing 33,746 heat flow measurements from the International Heat Flow Commission's most recent Global Heat Flow Database. The mean heat flow for the observational data set is 95.83 mWm−2 with a spatially averaged heat loss of 40.7 TW. We use a random forest regression MLA combined with a conformal prediction to predict in situ heat flow and its associated uncertainty for marine environments at a 100 km2 global resolution. Ten‐fold cross‐validation yields an R2 value of 0.4, indicating predictive skill. Geospatial prediction results in a global marine surface weighted in situ heat flow average of 69.67 ± 20.01 mWm−2 with a corresponding heat loss of 29.59 ± 5.78 TW. Additionally, parametric isolation is calculated to highlight areas where additional heat flow measurements would be beneficial to directly improve the overall prediction. The resultant in situ heat flow and parametric isolation maps serve as a tool to further heat flow studies within the community.

Heat Transfer and Flow Study in a Pipe with Ring-Type Inserts: Experiment Study

Heat Transfer and Flow Study in a Pipe with Ring-Type Inserts: Experiment Study

MATHEMATICAL STUDY OF BLOOD CIRCULATION AND BIO-CHEMICAL REACTION BASED HEAT DISTRIBUTION PROBLEM IN HUMAN DERMAL REGION

In this paper we study heat distribution in outer parts of human body incorporating effect of blood circulation and metabolic activities. We solve the bio heat equation of skin for steady state case using Whittaker function and Conuent Hypergeometric function. Some parameters are taken variable. A general model has been modified and solved mathematically for comparative study of heat flow in human skin. The structure of human skin is taken as heterogeneous medium and attempt has been made to solve it by analytic methods. Numerical computation has been carried out for various values of parameters.

Heat flow in the Main Karoo Basin, South Africa

Abstract The Main Karoo Basin, and its Late Carboniferous to Early Jurassic stratified fill, the Karoo Supergroup, is the largest geological entity in South Africa and one of the economically most strategic because of its coal resources and potential shale gas resources. It also has a potential future in renewable energy in the form of geothermal energy. Although the basin has not received sufficient dedicated attention from a thermal perspective, numerous heat flow studies have resulted in the gradual accumulation of a substantial data base of the thermal conductivity of the constituent rocks, geothermal gradients and heat flow data. The main purpose of this paper is to collate this information, as well as new observations and thus generate a reference for future geothermal investigations. Approximately 900 conductivity measurements have resulted in well-established average conductivities for most stratified rock types, which vary by an order of magnitude from less than 0.3 W m-1 K-1 for coal to more than 5.0 W m-1 K-1 for sandstone. The maximum recorded temperature in the deepest parts of the basin (greater than 5 km) is 160°C and the overall average thermal gradient is approximately 29 K/km, which is greater than most other geological environments in southern Africa. The heat flow at 74 localities varies in the range 41 to 83 mW m-2 and the average for the central and southern parts of the basin is 62 ± 11 mW m-2 (34 values); this is approximately equal to the average heat flow for the mid-Proterozoic Namaqua tectonic province that underlies the southern half of the basin. The heat flow decreases to less than 50 mW m-2 in the northern and north-western parts of the basin, which values are typical of the underlying Archaean Kaapvaal Craton. Simple models illustrate the application of the heat flow and thermal conductivity data for calculating crustal temperature in the Karoo Basin.

Lithospheric S-velocity structure of the on-shore Potiguar Basin, NE Brazil: High heat-flow in an aborted rift

The lithospheric structure of the on-shore Potiguar Basin has been investigated through velocity-depth profiles developed from the joint inversion of receiver functions and surface-wave dispersion at 16 seismic stations in and around the basin. The Potiguar Basin is an aborted rift basin that formed during the opening of the South Atlantic Ocean in the Lower Cretaceous, and is characterized by an unusual surface heat-flow with values as high as 101 mW/m2. Our results reveal: (i) A relatively thin crust of ∼30 km below the on-shore Potiguar Basin and a relatively thicker crust of ∼32 km around the basin; (ii) the existence of an anomalous uppermost mantle of ∼4.3 km/s at 30–40 km depth under most seismic stations; and (iii) the presence of a negative velocity gradient centered at ∼125 km depth, which probably represents a shallow Lithosphere Asthenosphere Boundary (LAB). We argue that the anomalous uppermost mantle is associated with magmatic intrusions just below the Moho, deeper than previously postulated from independent heat-flow studies, and that those intrusions result from heating by an active, hot sublithospheric mantle under the basin that keeps the lithosphere thin. We further argue that heating from the magmatic intrusions, along with direct heating from the sublithospheric mantle, may explain the unusually elevated heat flow observed at the surface.

Natural convection flow on a bent wavy vertical enclosure filled with power-law nanofluid simulated by Element Free Galerkin method

The present paper contains a study of heat transfer and flow of a power-law nanofluid in bent vertical wavy walls enclosure. The system of governing equations has been solved by mesh free method (EFGM) with a parallel scheme. The results are found in terms of heat transfer rate at the hot wall, isotherms and streamlines under the influence of Aspect ratio, Rayleigh number, Prandtl number, power-law index and wave amplitude. It is observed that the average Nusselt number improves with enhancing the Prandtl number, Rayleigh number and aspect ratio but it decrements with enhancing the power-law index and surface waviness. A parallel implementation scheme gives better efficiency as compared to the sequential scheme. Such problems have direct application in electronic devices, food processing industries, and biomedical applications.

The Numerical Simulation and Experimental Study of Heat Flow in Seabed Sediments Based on COMSOL

In situ electrothermal conduction heating technology refers to the setting up of a heat source directly within the sediments, using the heat conductivity of the sediments and the heat radiation of the heat source for heat transfer to achieve the in situ heating of the sediments. The in situ electrothermal conduction heating of sediments has the disadvantage of the heating equipment being easily damaged and difficult to operate, and requires the equipment to be able to withstand seawater pressure and marine corrosion. In this paper, based on the combination of numerical simulations (using COMSOL Multiphysics software) and approximate in situ electrothermal conduction heating experiments, the temperature field and other factors of sediments heated by in situ conductive heating (in a specific area) were studied to determine a numerical model for sediment heat flow in a specific area under different pressures and initial temperatures, and the correctness of the numerical model was further verified by comparative experiments. The results of this study have important implications for future studies on the actual thermal properties of sediments and even heat transfer mechanisms during gas hydrate extraction.

Study of entropy generation and heat flow through a microtube induced by the membrane-based thermofluidics systems

A mathematical model to study the thermally fully developed pressure-driven flow of Newtonian fluid in a finite length vertical microtube with a spatial–temporal dependent membrane contraction, is presented. Here, pressure is generated by the membrane propagation and is further regulated by buoyancy forces. Besides, the energy equation refers to the movement of thermal energy between two walls of the microtube. This model examines the kinematics of membrane, flow and pumping characteristics, wall shear stress, Grashof number (Buoyancy force) effects, Nusselt number, isotherms, and entropy generation in the membrane based thermofluidics system. The dimensional analysis followed by the lubrication approach (since radius of the microtube is substantially less than its length) has been utilized to derive the analytical solutions which are further simulated by using the Matlab code for the graphical illustrations. The velocity fields under the effects of thermal properties and membrane kinematics are computed and noted that magnitude to axial velocity increases by 44.8% via the Grashof number in the range 0 to 4. Further, it is observed that the convective heat flow ( N u > 1 ) is performing in the range [ − 0 . 2 , 0 . 2 ] due to the rhythmic membrane kinematics. Another side, the membrane shape parameter is a major concern for the entropy generation. Such types of analysis and membrane based thermofluidics could be applicable to control the heat transfer rate and energy in various thermal treatments of biomedical sciences and engineering, and also help to design the thermo-pneumatic micropump. • A mathematical model for heat transfer in membrane based microtube is presented. • The membrane pumping mechanism is highly motivated by insect’s respiratory system. • The direct heat source increases the temperature elevation up to 49% in microtube. • Entropy can be controlled by relative temperature and membrane shape in the system. • The findings of the present model are useful in various thermal treatments.

Deep crustal structure and compositions for tectonic and geodynamic implications of the Dharwar Craton (Southern India) inferred from 3-C wide-angle seismic data

The 3-C deep seismic study with integrated interpretation of Bouguer gravity, heat flow, geological and geochronological studies along the Perur-Chikmagalur profile of the Dharwar Craton reveals important crustal elements with compositional distinctions of different geological structures such as horst and grabens , major shear zones like BSZ, CSZ, prominent batholiths as CG , granitic and gneissic complexes, presence of LVL, plutons , magmatic intrusives, thick underplating in WDC and significant Moho upwarping towards EDC due to plume head and komatiite magmatism . • Crustal V P and V S models are derived using 3-C seismic data of the Dharwar Craton. • Rock compositions are constrained by V P / V S , Poisson’s ratio, density and heat-flow. • Imaged a major suture zone CSZ dividing EDC and WDC blocks of the Dharwar Craton. • The LVL forms a detachment zone sandwiching the supracrustals and Archean gneisses. • Moho upwarping and underplating justify plume-arc settings for the Dharwar Craton. The Dharwar Craton of southern India is an important stable cratonic province of the world with complex geology and tectonic settings. Extensive studies provide insights of crustal velocity structure for the tectonic and geodynamic evolution of this Archean craton. This region has experienced several tectonically disturbed zones like Chitradurga Shear Zone (CSZ), Bababudan Shear Zone (BSZ) and Closepet Granites (CG). We have developed a comprehensive geologically plausible tectonic model using both P- and S-wave velocity structures to image major structural elements like shear zones and decipher the compositional distinctions of different rock assemblages of Western Dharwar Craton (WDC) and Eastern Dharwar Craton (EDC) part using 3-C wide-angle seismic data acquired along the 200-km long Perur-Chikmagalur deep seismic profile. The tectonic model show large compositional changes of subsurface rocks with anomalous high V P , V S , V P / V S , Poisson’s ratio ( σ ) and density ( ρ ) forming a major tectonic divide or suture zone called CSZ between EDC and WDC blocks. Significant crustal thinning (37–41 km) is observed due to Moho upwarping towards the Neo-Archean EDC block mainly composed of felsic granites and granodiorites. The WDC block show relatively thick crust (48–50 km) due to mafic underplating and mantle plume activity below CSZ forming Meso-Archean greenschist-facies-gneisses with dominant mafic/ultra-mafic compositions. Hence, crustal velocity, density, heat-flow, geology and geochronology studies support a plume-arc model with evidence of thick magmatic underplating of the lower-crust, complex subduction and development of highly strained shear zones like CSZ as suture juxtaposing EDC and WDC blocks.

Evaluation of Thermal anomaly Preceding Northern Red Sea Earthquake, the 16th June 2020

On the 16th June, 2020, a moderate earthquake (Mw = 5.2) hit the Northern Red Sea region, Egypt, that was felt throughout the Hurghada and Sharm El-Sheikh cities and the surrounding areas without any damages. The thermal anomaly before the earthquakes was widely studied with satellite data, such as NOAA/AVHRR and MODIS. The case study aims to monitor and demonstrate the possibility of any variation of the thermal anomaly of sea surface temperature (SST) before and after the 16th June 2020 earthquake and to correlate the results with the previous heat flow study (deep thermal action). The Daytime/Nighttime (SST) data are retrieved from the OBPG serves as a Distributed Active Archive Center (OB. DAAC). The outputs indicated a thermal anomaly on the June 12th, 2020 a few days before the earthquake, covered a large area around the epicenter 60 km impact area, and reached a high value on the 15th June 2020, one day before the earthquake. For the deep thermal action of the entire crust, the earthquake frequency distributions presumed from the reviewed catalogue indicated that the peak of the seismicity is concentrated close to the center of the rift axis in the Northern Red Sea. The heat flow measurements are increased toward the center of the Red Sea rift and decreased toward both sides, generating some partial melt of the rocks and producing crustal subsidence at the center of the Red Sea rift. These results are compatible with the pattern of the seismic activity and heat flow effect around the epicenter. It could be considered as a short-term precursor of the earthquake.

Heat Flow and Thermal Source of the Xi’an Depression, Weihe Basin, Central China

The Xi’an Depression of the Weihe Basin, located in the transition zone where the North China, Qinling and Yangtze plates collide with each other, is an important area of geothermal energy utilization in China. Studies of heat flow and thermal sources are of great significance to the exploration and development of geothermal resources in this area. In this paper, six temperature logs boreholes, and 14 thermal conductivity samples have been used to study the geothermal gradient and terrestrial heat flow in the area. The results show that the geothermal gradients of Xi’an Depression range from 20.8 C/km to 49.1 C/km, with an average of 31.7 ± 5.0 C/km. The calculated heat flow is 59.4–88.6 mW/m2, and the average value is 71.0 ± 6.3 mW/m2, which indicates a high thermal background in the area. The high anomalous zones are near the Lintong-Chang’an Fault zone in the southeast, the Weihe Fault in the north, and the Fenghe Fault in the central Xi’an Depression. These deep and large faults not only control the formation of the Xi’an Depression but also provide an important channel for the circulation of groundwater and affect the characteristics of the shallow geothermal distribution. The temperature of the Moho in the Xi’an Depression ranges from 600 to 700°C, and the thermal lithosphere thickness is about 90–100 km. The characteristics of lithospheric thermal structure in Xi’an Depression indicate that the higher thermal background in the study area is related to lithospheric extension and thinning and asthenosphere thermal material upwelling.

Heat Flow Studies in India: An Update

Abstract The geothermal study in India was initiated in 1962 and in the last six decades it grew in concurrence with the international programmes of geothermal study on several fronts, such as, characterizing heat flow for the major geological units; measuring the thermal conductivity of crustal rocks at ambient and elevated temperatures; arriving at the best mathematical model of thermal conductivity from modal mineralogy; calculating radiogenic heat production for the major rock formations; modeling crustal and sub-crustal thermal structure for the stable regions; calculating mantle temperature constrained with seismic velocities and mantle xenoliths; assessing geothermal energy potential regions and using geothermal observations to estimate past climate changes. Systematic heat flow, thermal conductivity, heat production, and thermal modelling carried out during this period of time led to the refinement of classical thermal models of the continental crust, i.e., from linear-step-exponential heat production model based on linear relationship, to realistic heat production models based on regional geology and regional crustal structure from geophysical studies. In many cases, such studies have also helped in the exploration of geothermal energy potential regions, geo-engineering works and deciphering past climate changes. Future research goals include to study (i) crustal and upper mantle thermal structure in the unexplored geological provinces, active tectonic zones, sedimentary basins, and hot spring areas of the Indian sub-continent, (ii) thermal structure in the adjoining oceanic regions, occurrence of potential geothermal energy resources, (iii) thermal properties of rocks at elevated temperature and their implications in refining lithospheric thermal model, (iv) linkage between geothermal and meteorological records for past climate change.

Numerical study on Alpha Magnetic Spectrometer thermal response under adjustment process of International Space Station flying attitude with the key angle variable

The thermal environment of the Alpha Magnetic Spectrometer installed on the International Space Station was found to be affected by its attitude adjustment causing temperature anomalies. In previous studies, the abnormal temperature responses and the corresponding control measures were studied systematically, but the influence of the attitude adjustment process with the key angle variable was not considered adequately. Here we report a numerical study of the exterior heat flow and temperature responses of the Alpha Magnetic Spectrometer during the attitude adjustment process of the International Space Station, along with the thermal control effect on temperature anomalies caused by the key angle variable that determines the flight attitude. As results, the change process of the key angle variable determining the flight attitude may cause a maximum exterior heat flow difference of 479.28 W/m2 and a temperature difference of 46.03 °C, respectively, and even inducing temperature anomalies occurring in a time range from 4619 s to 37641 s. The existing temperature control measure that rotates the International Space Station starboard radiator exhibits different effects with the variation of the angle variable. Among them, 67.6% of the temperature anomaly cases can be suppressed, suggesting the possibility of further thermal control in orbit.

Estimating the effective elastic thickness of the Arctic lithosphere using the wavelet coherence method: Tectonic implications

Currently, knowledge of structure and tectonic evolution of the Arctic lithosphere remains limited. The effective elastic thickness of the lithosphere (Te) is a parameter that describes the lithospheric integrated strength and reflects its thermal and rheological properties, which helps to reveal intraplate tectonic process. In this study, we present a high-resolution Te model in the Arctic region (north of 67°N), which is highly heterogeneous and strongly correlated with various regional tectonic elements. To verify the recovered Te, its pattern is compared to those obtained in previous studies that used different methods and to available heat flow measurements and seismic velocity model and shows good agreement. High Te values are found in the Greenland shield, North American craton and Siberian craton, which are compatible with results from previous studies of high seismic velocity and low heat flow, suggesting that cold, thick lithosphere remains tectonically undisturbed. Low Te values occur in the Amerasia Basin, Baffin Bay, Eurasia Basin and North Atlantic Ocean where young oceanic lithosphere is created. Moreover, the areas affected by regional volcanism in the Siberian Traps and HALIP are dominated by reductions in Te, which we attribute to thermal rejuvenation triggered by the intrusion of magma. Weak lithosphere also dominates in tectonically active orogens as well, including the Alaska-Chukotka, Novaya Zemlya and Caledonides, and is related to the stress released during collisional deformation. We find that a few deep sedimentary basins are characterized by intermediate Te, which implies mechanical support of the surface sediment loads in a non-isostatic state. Our new Te model provides potentially significant insights into various tectonic and geodynamic problems of the Arctic lithosphere.