Subsurface temperature maps in French sedimentary basins: new data compilation and interpolation

2010 ◽  
Vol 181 (4) ◽  
pp. 377-390 ◽  
Author(s):  
Damien Bonté ◽  
Laurent Guillou-Frottier ◽  
Cynthia Garibaldi ◽  
Bernard Bourgine ◽  
Simon Lopez ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Surface Temperature ◽  
Cross Sections ◽  
Large Scale ◽  
Thermal Structure ◽  
Three Dimensional ◽  
Sedimentary Basins ◽  
Local Character ◽  
Data Compilation ◽  
Temperature Maps

Abstract Assessment of the underground geothermal potential requires the knowledge of deep temperatures (1–5 km). Here, we present new temperature maps obtained from oil boreholes in the French sedimentary basins. Because of their origin, the data need to be corrected, and their local character necessitates spatial interpolation. Previous maps were obtained in the 1970s using empirical corrections and manual interpolation. In this study, we update the number of measurements by using values collected during the last thirty years, correct the temperatures for transient perturbations and carry out statistical analyses before modelling the 3D distribution of temperatures. This dataset provides 977 temperatures corrected for transient perturbations in 593 boreholes located in the French sedimentary basins. An average temperature gradient of 30.6°C/km is obtained for a representative surface temperature of 10°C. When surface temperature is not accounted for, deep measurements are best fitted with a temperature gradient of 25.7°C/km. We perform a geostatistical analysis on a residual temperature dataset (using a drift of 25.7°C/km) to constrain the 3D interpolation kriging procedure with horizontal and vertical models of variograms. The interpolated residual temperatures are added to the country-scale averaged drift in order to get a three dimensional thermal structure of the French sedimentary basins. The 3D thermal block enables us to extract isothermal surfaces and 2D sections (iso-depth maps and iso-longitude cross-sections). A number of anomalies with a limited depth and spatial extension have been identified, from shallow in the Rhine graben and Aquitanian basin, to deep in the Provence basin. Some of these anomalies (Paris basin, Alsace, south of the Provence basin) may be partly related to thick insulating sediments, while for some others (southwestern Aquitanian basin, part of the Provence basin) large-scale fluid circulation may explain superimposed cold and warm anomalies.

scholarly journals Changing available energy for extratropical cyclones and associated convection in Northern Hemisphere summer

2019 ◽  
Vol 116 (10) ◽  
pp. 4105-4110 ◽  
Author(s):  
Charles G. Gertler ◽  
Paul A. O’Gorman
Keyword(s):  
Temperature Gradient ◽  
Surface Temperature ◽  
Northern Hemisphere ◽  
Large Scale ◽  
Thermal Structure ◽  
Extratropical Cyclone ◽  
Extratropical Cyclones ◽  
Cyclone Activity ◽  
Available Energy ◽  
The Mean

The circulation of the Northern Hemisphere extratropical troposphere has changed over recent decades, with marked decreases in extratropical cyclone activity and eddy kinetic energy (EKE) in summer and increases in the fraction of precipitation that is convective in all seasons. Decreasing EKE in summer is partly explained by a weakening meridional temperature gradient, but changes in vertical temperature gradients and increasing moisture also affect the mean available potential energy (MAPE), which is the energetic reservoir from which extratropical cyclones draw. Furthermore, the relation of changes in mean thermal structure and moisture to changes in convection associated with extratropical cyclones is poorly understood. Here we calculate trends in MAPE for the Northern extratropics in summer over the years 1979–2017, and we decompose MAPE into both convective and nonconvective components. Nonconvective MAPE decreased over this period, consistent with decreases in EKE and extratropical cyclone activity, but convective MAPE increased, implying an increase in the energy available to convection. Calculations with idealized atmospheres indicate that nonconvective and convective MAPE both increase with increasing mean surface temperature and decrease with decreasing meridional surface temperature gradient, but convective MAPE is relatively more sensitive to the increase in mean surface temperature. These results connect changes in the atmospheric mean state with changes in both large-scale and convective circulations, and they suggest that extratropical cyclones can weaken even as their associated convection becomes more energetic.

scholarly journals Stereological Estimation of Orientation Distribution of Generalized Cylinders from a Unique 2D Slice

2013 ◽  
Vol 19 (6) ◽  
pp. 1678-1687 ◽  
Author(s):  
Jean-Pierre Da Costa ◽  
Stefan Oprean ◽  
Pierre Baylou ◽  
Christian Germain
Keyword(s):  
Cross Sections ◽  
Composite Structures ◽  
Large Scale ◽  
Fibrous Composite ◽  
Three Dimensional ◽  
Synthetic Data ◽  
Inequality Constraints ◽  
Orientation Distribution ◽  
Industrial Applications ◽  
Cost Constraints

AbstractThough three-dimensional (3D) imaging gives deep insight into the inner structure of complex materials, the stereological analysis of 2D snapshots of material sections is still necessary for large-scale industrial applications for reasons related to time and cost constraints. In this paper, we propose an original framework to estimate the orientation distribution of generalized cylindrical structures from a single 2D section. Contrary to existing approaches, knowledge of the cylinder cross-section shape is not necessary. The only requirement is to know the area distribution of the cross-sections. The approach relies on minimization of a least squares criterion under linear equality and inequality constraints that can be solved with standard optimization solvers. It is evaluated on synthetic data, including simulated images, and is applied to experimental microscopy images of fibrous composite structures. The results show the relevance and capabilities of the approach though some limitations have been identified regarding sensitivity to deviations from the assumed model.

scholarly journals Performance Assessment of Reference Modelling Methods for Defect Evaluation in Asphalt Concrete

Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8190
Author(s):  
Pauli Putkiranta ◽  
Matti Kurkela ◽  
Matias Ingman ◽  
Aino Keitaanniemi ◽  
Aimad El Issaoui ◽  
...  
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Laser Scanning ◽  
Large Scale ◽  
Three Dimensional ◽  
Qualitative Assessment ◽  
Three Dimensional Mapping ◽  
Road Surfaces ◽  
Three Dimensional Measurement ◽  
Mobile Methods

The deterioration of road conditions and increasing repair deficits pose challenges for the maintenance of reliable road infrastructure, and thus threaten, for example, safety and the fluent flow of traffic. Improved and more efficient procedures for maintenance are required, and these require improved knowledge of road conditions, i.e., improved data. Three-dimensional mapping presents possibilities for large-scale collection of data on road surfaces and automatic evaluation of maintenance needs. However, the development and, specifically, evaluation of large-scale mobile methods requires reliable references. To evaluate possibilities for close-range, static, high-resolution, three-dimensional measurement of road surfaces for reference use, three measurement methods and five instrumentations are investigated: terrestrial laser scanning (TLS, Leica RTC360), photogrammetry using high-resolution professional-grade cameras (Nikon D800 and D810E), photogrammetry using an industrial camera (FLIR Grasshopper GS3-U3-120S6C-C), and structured-light handheld scanners Artec Leo and Faro Freestyle. High-resolution photogrammetry is established as reference based on laboratory measurements and point density. The instrumentations are compared against one another using cross-sections, point–point distances, and ability to obtain key metrics of defects, and a qualitative assessment of the processing procedures for each is carried out. It is found that photogrammetric models provide the highest resolutions (10–50 million points per m2) and photogrammetric and TLS approaches perform robustly in precision with consistent sub-millimeter offsets relative to one another, while handheld scanners perform relatively inconsistently. A discussion on the practical implications of using each of the examined instrumentations is presented.

Local Character Tensors for 3D Registration Method on Free-View Datasets

2007 ◽  
Vol 11 (7) ◽  
pp. 848-857
Author(s):  
Jingjing Wang ◽  
◽  
Fangyan Dong ◽  
Yutaka Hatakeyama ◽  
Hajime Nobuhara ◽  
...  
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Geometric Object ◽  
Computational Time ◽  
Object Model ◽  
3D Registration ◽  
Registration Method ◽  
Local Character ◽  
Optimal Segmentation ◽  
Matching Probability

A local character tensor is proposed for the automatic three-dimensional (3D) pair-wise registration based on free-view 3D datasets. In the proposed method, there are two characters, i.e., the optimal segmentation to realize the automatic processing and local character tensor to improve the matching probability. It is applied for solving the mismatching problem and large-scale 3D datasets, using non-structured datasets are tested in a PC with Intel Pentium M 1.50 GHz and 1.0 GB memory. Pair-wised experimental results show the proposed method increases average 12.6% matching probability and decreases average 18.9 seconds computational time compared to the conventional local character based registration method. This registration method can be further applied to 3D reconstruction from navigation, model based object recognition to accurate 3D geometric object model application.

scholarly journals UAV-BASED PHOTOGRAMMETRY FOR ARCHAEOLOGICAL HERITAGE SITE SURVEY AND 3D MODELING OF THE SARDUS PATER TEMPLE (ITALY)

2019 ◽  
Vol XLII-2/W17 ◽  
pp. 45-51
Author(s):  
V. Bagnolo ◽  
N. Paba
Keyword(s):  
Cross Sections ◽  
Large Scale ◽  
Three Dimensional ◽  
High Standard ◽  
3D Models ◽  
Strong Increase ◽  
Active Sensors ◽  
Archaeological Heritage ◽  
Heritage Site ◽  
Effective Visualization

Abstract. Despite the high standard guaranteed by 3D scanning technology, image based modeling establishes the most widely used technique for surface reconstruction, being a cheaper and more portable approach. The strong increase in the use of Unmanned Aerial Vehicles (UAVs), is increasingly affirming and consolidating over the years. Being more cheap and portable than the active sensors approach, the combination of photogrammetry and drones is widely used for different applications both for large scale mapping and for documentation of architecture and archaeological heritage. UAV based photogrammetry allows for rapid accurate mapping and three-dimensional modelling. Over the last two decades, the study of archaeological sites have benefited from the constant evolution of sensor-based surveying techniques, finding effective application for purely visualization purposes or for the extraction of metric data. The Punic-Roman temple "Sardus Pater Babai" in southern Sardinia (Italy), has been the subject of a massive anastylosis. The close-range photogrammetry technique, exploiting the images produced by a UAV consumer and the GNSS system data, has allowed the creation of metrically correct 2D and 3D models useful also for an effective visualization of the information. A series of ortho-images has been extracted in order to represent plan, elevations and cross-sections of the monument.

Coherent changes in large-scale thermal structure and baroclinic life cycle of synoptic eddies in the Northern Hemisphere under global warming

2020 ◽  
Author(s):  
Pei-Chun Hsu ◽  
Huang-Hsiung Hsu
Keyword(s):  
Global Warming ◽  
Life Cycle ◽  
Temperature Gradient ◽  
Northern Hemisphere ◽  
Large Scale ◽  
Thermal Structure ◽  
Mean Flow ◽  
Upper Troposphere ◽  
The Past ◽  
Synoptic Eddies

<p><strong>There is a growing concern that human-induced climate change has been affecting weather systems. However, robust observational evidences that confirm the links between global warming and synoptic phenomena at the global scale are lacking. Here we reveal robust covarying signals between poleward temperature gradient and baroclinic life cycle of synoptic (1-10 days) eddies under global warming. We note that the changes in temperature structure in Northern Hemisphere winter and summer in the past decades are different. In boreal winter, the tropospheric warming has been larger in tropical upper troposphere and around 30°N than for the midlatitude (30-60°N). This inhomogeneous warming resulted in the enhancement of poleward temperature gradient in the subtropical upper troposphere and in the lower midlatitude (30-45°N). We observed correlated increasing trends in the entire baroclinic life cycle of synoptic eddies</strong><strong> — </strong><strong>including eddy fluxes of heat and momentum, and zonal mean jet</strong><strong> — </strong><strong>associated with steepened poleward temperature gradients in these regions in the winter Northern Hemisphere over the past four decades. By contrast, in the summer Northern Hemisphere, the overall tropospheric warming over the mid- to high-latitude land areas has been accompanied by weakly reduced synoptic eddy activities and zonal mean flow. Our findings suggest that if greenhouse gas–induced warming continue to change the atmospheric thermal structure as projected in a warming climate, extratropical synoptic disturbances and large-scale circulations may change accordingly. </strong></p>

scholarly journals Application of GO Management in Bistatic RCS Computation Using the Vector Parabolic Equation Method

2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
X. J. Zhong ◽  
T. J. Cui ◽  
J. F. Zhang ◽  
W. M. Yu
Keyword(s):  
Parabolic Equation ◽  
Cross Sections ◽  
Large Scale ◽  
Three Dimensional ◽  
Original Method ◽  
Good Choice ◽  
Bistatic Radar ◽  
Large Scale Problems ◽  
Radar Cross Sections ◽  
Resultant Matrix

The parabolic equation (PE) method is a good choice in solving large-scale problems, but the resultant matrix is usually ill conditioned. In this letter, we introduce the geometric optics (GO) management in the calculation of bistatic radar cross sections using three-dimensional vector PE method. This method manages the object surface by GO, and hence the ill-conditioned problem can be avoided. Examples are given using the presented method, original method, and the method of moments. Results show the validity and stability of the presented method.

scholarly journals Three-dimensional thermal structure of subduction zones: effects of obliquity and curvature

2012 ◽  
Vol 4 (2) ◽  
pp. 919-941 ◽  
Author(s):  
A. K. Bengtson ◽  
P. E. van Keken
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Subduction Zones ◽  
Mantle Wedge ◽  
Thermal Structure ◽  
Critical Role ◽  
Three Dimensional ◽  
Arc Volcanism ◽  
Oblique Subduction ◽  
Dehydration Reactions

Abstract. Quantifying the precise thermal structure of subduction zones is essential for understanding the nature of metamorphic dehydration reactions, arc volcanism, and intermediate depth seismicity. High resolution two-dimensional (2-D) models have shown that the rheology of the mantle wedge plays a critical role and establishes strong temperature gradients in the slab. The influence of three-dimensional (3-D) subduction zone geometry on thermal structure is however not yet well characterized. A common assumption for 2-D models is that the cross-section is taken normal to the strike of the trench with a corresponding velocity reduction in the case of oblique subduction, rather than taken parallel to velocity. A comparison between a full 3-D Cartesian model with oblique subduction and selected 2-D cross-sections demonstrates that the trench-normal cross-section provides a better reproduction of the slab thermal structure than the velocity-parallel cross-section. An exception is found in the case of strongly curved subduction, such as in the Marianas, where strong 3-D flow in the mantle wedge is generated. In this case it is shown that the full 3-D model should be evaluated for an accurate prediction of the slab thermal structure.

Analytical, Numerical, and Experimental Investigation of the Flow Structure in a Flooded Ball Bearing

1996 ◽  
Vol 118 (4) ◽  
pp. 865-871 ◽  
Author(s):  
Daniel H. Fruman ◽  
Ibtissem Benmansour ◽  
Che´rif Nouar ◽  
Thierry Bidot ◽  
Jean-Marc Vanel
Keyword(s):  
Analytical Model ◽  
Cross Sections ◽  
Large Scale ◽  
Ball Bearing ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Magnitude Estimate ◽  
Scale Model ◽  
Turbulent Regime ◽  
Dimensional Flow

Using an order of magnitude estimate of the leading terms in the equations of motion, the three-dimensional flow in a flooded ball bearing is reduced to the investigation of two-dimensional flow problems in a series of bearing cross sections. Combining, through appropriate compatibility conditions, the individual analytical solutions for the spaces confined between the cage and the inner wall of the rings, the halls and the rings and the balls and the cage’s holes, a very simple analytical model is derived. It allows the computation, in the laminar regime, of the flow rate, the pressure drop, and the velocity profile in different cross sections of the confined spaces. The results of the analytical model are confirmed by those obtained using a CFD code and extended to the turbulent regime. The analytical and numerical results are compared to those obtained from flow visualizations and velocity measurements conducted in a specially designed large scale model of a ball bearing. The agreement is very satisfactory.

scholarly journals Large-scale ice-sheet modelling as a means of dating deep ice cores in Greenland

1997 ◽  
Vol 43 (144) ◽  
pp. 307-310 ◽  
Author(s):  
Ralf Greve
Keyword(s):  
Surface Temperature ◽  
Large Scale ◽  
Piecewise Linear ◽  
Three Dimensional ◽  
Ice Sheet ◽  
Greenland Ice Sheet ◽  
Ice Cores ◽  
Temperature History ◽  
Geothermal Heat ◽  
Annual Layer

Abstract The three-dimensional ice-sheet model SICOPOLIS is used to simulate the dynamic/thermody namic behaviour of the entire Greenland ice sheet from 250 000 a BP until today. External forcing consists of a surface-temperature history constructed from δ18O data of the GRIP core, a snowfall history coupled linearly to that of the surface temperature, a piecewise linear sea-level scenario and a constant geothermal heat flux. The simulated Greenland ice sheet is investigated in the vicinity of Summit, the position where the maximum elevation is taken, and where the two drill sites GRIP and GISP2 are situated 28km apart from each other. In this region, the agreement between modelled and observed topography and ice temperature turns out to be very good. Computed age-depth profiles for GRIP and GISP2 are presented, which can he used to complete the dating of these cores in the deeper regions where annual-layer counting is not possible. However, artificial diffusion influences the computed ages in a near-basal boundary layer of approximately 15% of the ice thickness, so that the age at the bottom of the cores cannot be predicted yet.

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