Search

For the first time, a qualitative and quantitative analysis of the geomagnetic field and oil and gas capacity was performed for the territory of the Carpathian region, which made it possible to reveal the connection of hydrocarbon deposits with the magnetization of the Earth’s crust at the regional and local levels and the features of the deep structure of the Earth’s crust according to seismic data. The regularity of the distribution of oil and gas deposits of the Carpathian oil and gas-bearing region revealed by geomagnetic criteria is confirmed by their connection with regional and local anomalies of the gravity field and heat flow density. According to the analysis of the regional geomagnetic field and magnetic models along the PANCAKE and RomUkrSeis geotraverses, gas fields are located above the magnetic blocks of the middle and lower parts of the Earth’s crust or in their marginal parts, and oil fields are located above practically non-magnetic deep blocks. Under the thrust part of the Carpathian arc, the regional features of the Earth’s crust structures are clearly manifested, namely, starting from the longitude of the city of Rakhiv, the submeridional direction of extension of regional anomalies of magnetic, gravity, and thermal fields and their horizontal gradient zones prevails. The oil and gas potential of the region is in good agreement with this — the gas fields are timed to the minimum values of the regional horizontal gradient of the regional magnetic field, to the increased gradient of Bouguet anomalies, as well as to the minimum values of the horizontal gradient of heat flow density anomalies. In local geophysical fields, gas fields are gravitating: to weakly negative magnetic anomalies and their gradient zones; to negative anomalies of the gravitational field predominantly; to positive anomalies of heat flow density in the northwest, within the area of Trans-European suture zone (without the middle of the Krakovets fault), and negative anomalies in the Carpathian trough. Oil and oil condensate deposits are correlated with a band of positive magnetic field anomalies, negative gravity field anomalies, and increased heat flux density values. The main deep faults of the Carpathian region and the marginal part of the Platform in the first approximation can be considered Velikomostivsko-Chernivetsky, which characterizes the change in the character of magnetic and gravity fields and heat flow density, Rava-Rusky, which reflects the zone of articulation of the Eastern and Western European platforms, Pre-Carpathian — the border of the Pre-Carpathian trough and the Folded Carpathians on the Earth’s surface (as well as the boundary of the Archaean(?)-Paleoproterozoic and Meso-Neoproterozoic crust according to the modern international chronostratigraphic scale), as well as the Transcarpathian fault. On the basis of magnetic and seismic data, the hypothetical depth position of these faults and the possible connection with them of hydrocarbon flows into the upper part of the Earth’s crust are proposed. Therefore, the geomagnetic criteria of the oil and gas bearing capacity of the Earth’s crust of the Carpathian region are agreed based on the results of the study of the gravity field and heat flow density anomalies, which makes it possible to predict the spread of oil and oil condensate and gas and gas condensate deposits according to the regional and local features of these fields in a first approximation., Уперше для території Карпатського регіону виконано якісний та кількісний аналіз геомагнітного поля і нафтогазоносності, який дав змогу виявити зв’язок родовищ вуглеводнів з намагніченістю земної кори на регіональному та локальному рівнях та особливостями глибинної будови земної кори за сейсмічними даними. Виявлена за геомагнітними критеріями закономірність поширення нафтових і газових родовищ Карпатської нафтогазоносносної області підтверджується їх зв’язком з регіональними та локальними аномаліями гравітаційного поля та густини теплового потоку. Згідно з аналізом регіонального геомагнітного поля та магнітних моделей уздовж геотраверсів PANCAKE та RomUkrSеis, газові родовища розташовуються над магнітни-ми блоками середньої та нижньої частин земної кори або в їх крайових частинах, а нафтові — над практично немагнітними глибинними блоками. Під насувною частиною Карпатської дуги чітко проявляються регіональні особливості структур земної кори, а саме починаючи з довготи м. Рахів переважає субмеридіональний напрямок простягання регіональних аномалій магнітного, гравітаційного та теплового полів і зон їх горизонтального градієнта. З цим добре узгоджується нафтогазоносність регіону — газові родовища приурочені до мінімальних величин горизонтального градієнта регіонального магнітного поля, підвищеного градієнта аномалій Буге, а також мінімальних значень горизонтального градієнта аномалій густини теплового потоку. В локальних геофізичних полях газові родовища тяжіють: до слабонегативних магнітних аномалій та їх градієнтних зон; переважно до негативних аномалій гравітаційного поля; позитивних аномалій густини теплового потоку на північному заході, в області Трансєвропейської шовної зони (безпосередньо Краковецького розлому), та негативних аномалій у Передкарпатському прогині. Нафтові та нафтоконденсатні родовища корелюють зі смугою позитивних аномалій магнітного поля, негативних аномалій гравітаційного поля та підвищених значень густини теплового потоку.Основними глибинними розломами Карпатського регіону та крайової частини платформи у першому наближенні можна вважати Великомостівсько-Чернівецький, який характеризує зміну характеру магнітного і гравітаційного полів та густини теплового потоку, Рава-Руський, що відображає зону зчленування Східно- та Західноєвропейської платформ, Передкарпатський — границю Передкарпатського прогину та Складчастих Карпат на земній поверхні (а також границю архей(?)-палеопротерозойської та мезо-неопротерозойської кори згідно із сучасною міжнародною хро-ностратиграфічною шкалою [Gradstein, Ogg, 2020]), а також Закарпатський розлом. На підставі магнітних і сейсмічних даних запропоновано гіпотетичне глибинне положення цих розломів та можливий зв’язок з ними потоків вуглеводнів у верхню частину земної кори. Отже, геомагнітні критерії нафтогазоносності земної кори Карпатського регіону узгоджуються з результатами дослідження гравітаційного поля та аномалій густини теплового потоку, що дає змогу прогнозувати у першому наближенні поширення нафтових і нафтоконденсатних та газових і газоконденсатних родовищ за особливостями регіональних та локальних полів.

This article deals with dynamic models for three-phase bearingless flux-switching permanent-magnet (FSPM) linear machines. This machine type can be used to build a magnetically levitating long-range linear drive system, whose rail does not need any active materials apart from iron. A dynamic machine model is developed by means of equivalent magnetic models, taking into account air-gap variation and magnetic saturation. The effects of these phenomena are analyzed using finite-element method (FEM) simulations of a test machine. The parameters of the proposed model can be identified using the FEM or measured data. The model can be applied to real-time control and time-domain simulations. The model is validated by means of experiments.

This paper proposes a space-vector dynamic model of the Synchronous Reluctance Motor (SynRM) including both self-saturation, cross-saturation effects, and iron losses expressed in state form, where the magnetizing current has been selected as a state variable. The proposed dynamic model is based on an original function between the stator flux and the magnetizing current components, improving a previously developed magnetic model. Additionally, the proposed model includes, besides the magnetic saturation, also iron losses. The proposed model requires 11 coefficients, among which 6 describe the self-saturation on both axes and 5 describe the cross-saturation. Starting from the definition of a proper co-energy variation function, both the static and dynamic inductances expressions have been analytically developed, so that the reciprocity condition for the cross-saturation is satisfied. This paper presents also a technique for the estimation of the parameters of the magnetic model and also the resistance describing the iron losses. This technique is based on the minimization of a suitably defined error function which includes the difference between the measured and estimated fluxes. The proposed parameter estimation technique has been tested in both numerical simulation and experimentally on a suitably developed test set-up and the proposed model has been thus validated experimentally

Исследуется проблема выбора параметра регуляризации при решении структурной обратной задачи магнитометрии для слоистой модели с помощью метода локальных поправок. Показано, что итоговое решение слабо зависит от значения параметра регуляризации., We study the problem of choosing the regularization parameter when solving the inverse problem of magnetometry for a layered model using the local corrections method. It is shown that the final solution weakly depends on the choice of the regularization parameter., Уральский геофизический вестник, Выпуск 3 (45) 2021, Pages 19-25

This study proposes an innovative compact design of a magnetically-driven capsule robot, which embeds an internal permanent magnet (IPM) with a cut-off cylindrical shape, to increase the effectiveness of the internal space distribution. After identifying the second central moment as the evaluation parameter of the efficient distribution of the capsule robot’s internal space, three different IPM configurations were compared. Then, the analytical magnetic forces and torques model of the cut-off cylinder-shaped design has been reported and validated by comparison of the analytical model, developed in MATLAB, with the model developed in COMSOL Multiphysics. The comparative results show that the cut-off cylinder-shaped magnet design guarantees a more efficient distribution of the internal space in all analysed cases, and the total mean error of the cut-off cylinder-shaped analytical magnetic model is less than 10%. In conclusion, the cut-off cylinder-shaped magnet compact design increases the efficiency of the distribution of the capsule internal space and the proposed model guarantees sufficient precision and great flexibility to justify its use.

International audience; This paper presents a noval 18 poles /16 slots Axial Flux Permanent Magnet-Assisted Synchronous Reluctance Motor (AF-PMASynRM) with non-overlapping concentrated winding. At first, the torque ripple and iron losses are analyzed using 3D Finite Element Analysis (3D-FEA). Then, a comparison between 3D-FEA and 2D-FEA based on flux and iron losses is established. In this paper, we propose to design the motor for high torque low speed application using a multiobjective optimization. In this kind of iterative procedure, the use of Finite Element is generally time consuming. Thus, we propose a 2D analytical saturated model that considers the local saturation near the iron bridges and the slot tangential leakage flux. The magnetic model is coupled with an electrical model that computes the power factor and the voltage at the motor terminals. A loss model is also developed to calculate the copper and the iron losses. The proposed analytical model is 5 times faster than the 2D- FEA. The optimal axial structure is compared to a previously optimized radial motor in order to evaluate the design benefits of axial flux machines.

For practical applications, we propose a technology for searching ordered sets of feasible solutions of the inverse magneto-prospecting problem. It is oriented towards using the elements of the guarantee approach, which is realized due to the construction and analysis of fairly broad communities of approximately equivalent solutions. One of the possible variants of this approach is considered, based on the idea of constructing the graphic structure of the target functional involved in the algorithms for automated selection. The necessary information is represented in the form of maps of the projection of the graphic structure. A technique for constructing such maps has been developed. The features of their application for organizing a purposeful search for the set of admissible solutions of the inverse problem are considered. An example of a multivariate approach for interpreting anomaly observations is given.

The article analyzes the pattern of displaying of the geological structure of the Eastern Azov region in a magnetic field. The anomalous magnetic field is separated on regional and residual components. The quantitative analysis of the anomalous magnetic field and their components to allocate magnetic-lineaments for the study area was done. Geochemical properties of the dyke rocks and their relation to the magnetization are given. It is demonstrated, the result of magnetic modeling of the Maloyanisolsky and of the Kamennomogilsky dyke swarms of Eastern Azov area.

On the base of analysis and generalization of total available geological-geophysical information accumulated during forty years passed a complex of geophysical models of the earth’s crust has been obtained, which gives up-to-date idea on deep structure of the central part of the Karelian craton. The plotted seismic 3D density and magnetic models define more exactly our notions on stratification of the earth’s crust, the behavior of geophysical boundaries including the crust-mantle one. Complex interpretation of potential fields based on seismic model of the earth’s crust of the region taking into account petro-physical and geological data, made possible to estimate special features of layered-blocky structure of the region and of structural correlation of sub-longitudinal suture (the fragment of Ladoga-Pechenga zone of multiple activization) in tectonic division and its relation to deep magnetic sources.

In this thesis, we present development of the first magnetic model of the main Proton Synchrotron magnets. The operation of the machine and conducting research on increasing its performance require a significant amount of the magnetic field data for the optics modelling. For magnets of the Proton Synchrotron, such amount of data cannot be provided by the magnetic measurements, therefore, we have to rely on magnetic models. We have developed the model based on the numerical analysis of the magnetic field in the magnet and performed the validation with the use of the available magnetic measurements data. The results of the 2D quasi-static analysis were used to decompose the multipolar contributions of different magnet circuits on different levels fo the iron core magnetization within the whole range of the PS operation energies. Established formulas of every circuit contributions take into account the global magnetization of the yoke and its saturation as well as a local magnetization changes caused by contributions of other circuits. The 3D numerical analysis was setup to study the influence of the magnet stray field and gaps between the magnet blocks on the integrated multipolar field. Its results were used to derive appropriate model corrections of the integrated multipolar field with respect to the field in the reference cross-section and to approximate the effective magnetic lengths of the auxiliary circuits of the PS magnet. In order to perform a non-linear chromaticity analysis and to take the full advantage of the developed model, we have modified the existing optics model of the PS lattice. We have integrated magnetic model into the optics calculation with two simulation adjustment methods, which optimize the main coil current in similar way as it is done for the real magnets and adjust four free parameters to match the measured parameters of the initial working point. We have successfully validated the combined magnetic and optics models for various beam momentum levels and magnet powering conditions. With the use of the new magnetic model, for the first time in the history of the PS we are able to predict a higher-order chromaticity function for any energy. Base on the optics modelling results, we have derived working point transfer matrices for the non-linear chromaticity, which allow to predict a set of powering current offsets required to apply foreseen working point adjustment. We were also able to model an offset of the measured transfer matrices due to a change of the radial position chosen for the beam production.

This work deals with the sizing of synchronous machines for hybrid vehicle applications. The use of the machine in the hybrid vehicle is characterized by high power consumption during a short time. This work proposes a strategy for minimizing the volume of the actuator by taking into account the real limits of temperature during the operating cycle. The sizing strategy is composed of two steps. The first step is the sizing optimization of the actuator with the operating point of the cycle. In this step we allow high level of flux density and the level of current density in the conductors exceeds the usual level for the continuous operating of the machine. These two parameters can reduce significantly the volume of the machine. However in this step, the temperatures are node checked. The second step checks the temperatures in the machine by simulating the entire cycle. So suitable models for optimization tools are carried out and are a compromise between the time computing and the required accuracy. Consequently, a magnetic model taking account of the cross saturation in the machine by using the nodal network method has been carried out ; efficient iron losses model in the flux weakening operation has been carried out and thermal model using too the nodal network method has been carried out. The thermal model is the main point for the sizing strategy so, a particular attention is needed. This model takes account of the flux directions in 3d and provides a good estimation of the temperatures in the actuator particularly in the heat zones as the slots and the end-windings. These results are checked by experimental tests realized in IFPEn on a special machine where thermocouples are implanted inside. We validated the thermal behavior in temperatures stabilized operation and in transitory temperatures operation. Next, these models have been implemented in multi-physics modeling for the optimization tool and for simulation tool. A study case has been introduced for a Kangoo hybrid vehicle where the electrical machine has to operate on each operating points of the Artemis cycle. With the results of the sizing strategy, we can conclude that for a working on cycle, le external volume of the magnetic parts of the machine can be reduce of 40 % compared with a sizing established by the usual rules in stabilized temperature operation. Furthermore, le volume reduction of the iron in the machine induces a reduction of the iron losses and we can conclude that the mean efficiency during the cycle stays good., Les travaux de recherche présentés dans ce document portent sur le dimensionnement de machines synchrones pour des applications de véhicules hybrides. L'utilisation de la machine électrique au sein du véhicule hybride est caractérisée par des appels de puissance de courtes durées. Cette thèse propose donc une stratégie de dimensionnement permettant de minimiser considérablement le volume de l'actionneur par la prise en compte des limites thermiques réelles lors du cycle de conduite. La stratégie de dimensionnement est composée de deux étapes. La première étape est l'optimisation du dimensionnement de l'actionneur à partir des points de fonctionnement du cycle. Nous autorisons des niveaux d'induction dans le fer élevés et des niveaux de densité de courant dans les conducteurs dépassant les niveaux habituellement autorisés pour un fonctionnement en régime permanent thermique. Ces deux points ont un impact réel sur le volume de la machine. Cela-dit, à ce stade, la thermique de la machine n'est prise en compte qu'indirectement en fixant une densité de courant dans les conducteurs. La seconde étape permet alors de vérifier la thermique par une simulation sur cycle pour ensuite réajuster si besoin la densité de courant et reprendre la première étape d'optimisation de la machine. Des modèles adaptés au processus d'optimisation ont alors été mis en place et offrent un bon compromis entre le temps de calcul et la précision requise. Par conséquent, un modèle magnétique prenant en compte la saturation croisée dans la machine utilisant la méthode nodale a été développé ; un modèle permettant une meilleure prise en compte des pertes fer notamment dans le zone de défluxage a également été développé ainsi qu'un modèle thermique en transitoire utilisant également la méthode nodale. Le modèle thermique étant la clé de la stratégie de dimensionnement, une grande attention y a été portée. Ce modèle permet de prendre en compte la direction des flux dans les trois dimensions et fournit de bonnes estimations des températures dans la machine notamment aux endroits les plus chauds comme les encoches et les têtes de bobines. Ces résultats ont été corroborés par des essais expérimentaux réalisés dans les bancs IFPEN sur une machine spécialement instrumentée en thermocouples. Cela a permis de valider le comportement thermique en régime permanent thermique et en régime transitoire thermique. Ces modèles ont ensuite été implantés dans une modélisation multi-physique pour l'outil d'optimisation et pour l'outil de simulation. Une étude de cas a été présentée pour un véhicule hybride Kangoo où la machine doit pouvoir assurer son fonctionnement pour un cycle Artémis urbain. Les résultats de la stratégie de dimensionnement permettent alors de conclure que sur cycle, le volume extérieur des parties actives de la machine électrique peut-être réduit de 40 % par rapport à un dimensionnement établi par les règles de l'art en régime permanent. De plus, la réduction du volume de fer dans la machine induit également une réduction des pertes fer ce qui nous permet de conclure que, toujours sur cycle, son rendement moyen reste élevé.

En la Islas Grande de Tierra del Fuego y Navarino, afloran los plutones Kranck, Jeujepen, Moat, Ushuaia, Trapecio, Santa Rosa y Castores. Todos estos plutones, seencuentran emplazados en corteza superior, con indicadores composicionalescaracterísticos de zonas de subducción. Utilizando datos aeromagnéticos disponiblesjunto a datos adquiridos de magnetismo terrestre y marino, se ha obtenido un mapacompleto de anomalías magnéticas para toda la zona de estudio. A partir de estainformación se ha realizado el modelado magnético 3D de los intrusivos estudiados,tomando en consideración los datos de topografía, el valor de susceptibilidad magnéticade cada intrusivo y la roca de caja, el campo magnético regional, el campo magnéticoremanente y las principales estructuras locales y regionales. Los resultados alcanzadosson presentados en bloques diagramas que integran los modelos obtenidos junto a lainformación geológica de superficie. Con carácter complementario se han realizadomuestreos piloto de anisotropía de susceptibilidad magnética, que indican la naturalezadominantemente ferromagnética de los intrusivos estudiados, con magnetita comoportador principal de la susceptibilidad. Para cada plutón se ha determinado la geometría, tamaño, volúmenes totales. Seobservaron dos modas en relación al tamaño de los plutones, un tamaño pequeño delorden de 1-10 km3 y otros de mayor tamaño del orden de 100 km3. La forma de losplutones pequeños es más laminar que las de los de mayores volúmenes. Se adquirieron 4 nuevos polos paleomagnéticos en 3 de los plutones estudiados (plutones Kranck, Santa Rosa y Castores) que abonan la hipótesis de que los Andes Fueguinos constituyen un arco primario, curvado en el Cretácico Medio-Superior, duranteel cierre de la Cuenca Marginal Rocas Verdes, a partir de un paleomargen curvopreexistente. Los valores del ángulo de inclinación (AI) de estos polos, permiten aportarinformación complementaria a la observada para las estructuras compresivas a nivelregional. En este sentido los AI de los plutones Jeujepen y Kranck del área norteestudiada, son mayores a los 30º, mientras que para los plutones del canal Beagle en elárea sur, se encuentran entre los 5 y 10º. Los primeros se encuentran afectados porestructuras compresivas, mientras que los del área sur, no están afectados por este tipode estructuras. Palabras claves: Tierra del Fuego, Plutones, Anomalías magnéticas, Modeladomagnético, Paleomagnetismo. In the islands of Tierra del Fuego and Navarino, outcrop the Kranck, JeuJepen, Moat, Ushuaia, Trapecio, Santa Rosa and Castores plutons. All these plutons are emplaced inthe upper crust and have characteristic compositional indicators of subduction zones. Using aeromagnetic available data along with land and marine magnetic data acquired, acomplete map of magnetic anomalies for the entire study area has been obtained. Fromthis information a 3D magnetic modeling of the studied intrusive has been made, takinginto consideration the topography data, the magnetic susceptibility values of eachintrusive and country rock, the regional magnetic field, the remanent magnetic field andthe major regional and local structures. The results obtained are presented in blockdiagrams that integrate the models obtained together with surface geological information. A complementary pilot sampling of anisotropy magnetic susceptibility has been done andindicate the ferromagnetic dominant nature of the intrusive with magnetite as the maincarrier of susceptibility. For each pluton the geometry, size, a total volumes has been determined. Two modeswere observed in relation to the plutons size, a small size of the range of 1-10 km3 andlarger ones of about 100 km3. The shape of the smaller plutons is more laminar than thelarger ones. Four new paleomagnetic poles acquired in three of the studied plutons (Kranck, Santa Rosa and Castore) support the hypothesis that he Fuegian Andes are a primary arc, bentin the Middle-Upper Cretaceous, during the closure of the marginal basin Rocas Verdes,from a preexisting curved paleomargin. The values of the inclination angle (AI) of thesepoles, provide additional information for the regional compressive structures. In this sensethe AI of the plutons Kranck and Jeujepen of the northern area, are greater than 30 °,while for the plutons of the Beagle Channel on the south, are between 5 and 10 º. Theformer are affected by compressive structures, while the southern area are not affected bythis type of structures. Keywords: Tierra del Fuego, Plutons, Magnetic Anomaly; Magnetic model, Paleomagnetism Fil: Peroni, Javier Ignacio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Inductors are used in analog circuits, power supplies, tube light circuits, also in electrical transmission systems, where they decrease influence of lightning strikes, switching and fault currents, etc. The simplest division of inductor type is on air core and iron core inductors. The latter ones are particularly difficult to model because of the ferromagnetic material nonlinearity. For modeling of electrical devices usually lumped and distributed parameter models are used. The main aim of this research is to provide a well working dynamic model of an iron core inductor, which includes magnetically nonlinear properties of iron core. The base of this study is a simple magnetically linear dynamic model which is further developed to two different types of magnetically nonlinear dynamic models. Both nonlinear dynamic models have been developed via mathematical derivation of equation which describes electrical subsystem of an iron core inductor. Benefit of the developed magnetically nonlinear dynamic model is capability for analysis of transient phenomena in inductors (inrush current).

The oceanic nature of the crust in northern Colombia (underlying the Lower Magdalena Basins) has been postulated by different authors as a northern extension of the Cretaceous, mafic and ultramafic rocks accreted to the western margin of northwest Colombia (in the Western Cordillera and Baudo range). Localized, small outcrops of oceanic affinity rocks seem to support this hypothesis. However, geophysical data do not support this northern extension, but clearly mark the boundary between the collisional Panamá terrane with northern South America and the over thrusting of the latter on top of the obliquely convergent Caribbean plate. We produced maps to basement and Moho topography by integrated modeling of gravity, magnetics, seismic reflection surveys and well data from northwest Colombia and the southwestern Caribbean. In areas with good seismic coverage, the basement under the Lower Magdalena Basins (LMB) is represented by a clear reflector. In areas where seismic data shows poor imaging or is absent, we use a back stripping methodology to model first the sedimentary section, with known densities, composition and geometry controlled by oil wells and high quality seismic data, and then the deeper section. 2,5D gravity and magnetics modeling results in an initial Moho that can be extended to the entire region based on the control of available seismic refraction points. This controlled Moho provides the basis for basement modeling for the whole area and this sequence is iterated for several sections across the region. Our results indicate that the crust under northern Colombia is continental to thinned continental (transitional) in nature, with densities between 2,6 and 2,7 g/cm3. Our model also requires a dense wedge of sediments (density 2,5 g/cm3) at the base of the modern fold belt, which may represent a fossil sedimentary wedge attached to the continental margin. This wedge may have served as a backstop for the modern fold belt. The gravity modeling does not require oceanic crust to form the basement in the Sinú and San Jacinto fold belts as previously suggested. Discrete layers and thin slivers of oceanic sediments and basement could have been scrapped off the incoming plate and thrusted into an accretionary mélange, and eventually exposed at the surface, as seen in the Mulatos, Chalan and Cansona locations. The shape of the continental wedge / oceanic crust boundary resembles that of a very low angle/flat subduction zone (ß angle between 2º to 3º), and is interpreted here as a low angle over thrusting of northern South America riding in a highly oblique direction over the underlying Caribbean plate. The map to basement depth obtained during this study forms the basis for basin analysis, oil maturation and evolutionary studies of the region. As an example, we apply our map to a flexural analysis of the LMB. La naturaleza oceánica de la corteza en el norte de Colombia (subyaciendo las cuencas del Valle Inferior del Magdalena) ha sido postulada por varios autores como una extensión al norte de las rocas Cretácicas, máficas y ultra máficas adosadas al margen Occidental del Nor Oeste de Colombia (en la Cordilleras Occidental y la Serranía del Baudó). Pequeños afloramientos, localizados, de rocas de afinidad oceánica aparentemente confirman esta hipótesis. Sin embargo, los datos geofísicos parecen no soportar esta extensión hacia el Norte, sino que claramente marcan el limite entre el terreno colisional de Panamá con el Norte de Sur América y los sobre cabalgamientos de esta ultima por encima de la placa oblicuamente convergente del Caribe. Hemos obtenido mapas del basamento y el Moho mediante el modelamiento integrado de gravimetría, magnetometria, sísmica de reflexión y datos de pozo del Norte de Colombia y el Sur Oeste del Caribe. En donde existe sísmica de reflexión la respuesta del basamento es muy clara. En áreas en donde los datos sísmicos son inexistentes o presentan pobre resolución, utilizamos una técnica de reconstrucción para modelar primero la sección sedimentaria, cuyas densidades, composición y geometría son conocidas, y se encuentra controlada por datos de pozos petroleros y sísmica de alta resolución. El modelamiento gravimetrico y magnetometrico en 2,5 D resulta en un Moho inicial que puede ser extendido a toda el área gracias al control de los puntos de sísmica de refracción disponibles. Este Moho controlado provee las bases para el modelamiento del basamento en toda el área de estudio, y esta secuencia es iterada para distintas secciones a través del área de estudio. Nuestros resultados indican que la corteza bajo el Norte de Colombia es de naturaleza continental a transicional (continental adelgazada). Nuestro modelo también requiere de una cuña densa de sedimentos (densidad de 2,5 g/cm3) a la base del cinturón deformado moderno, el cual podría representar una cuña sedimentaria fosilizada adosada al margen continental. Esta cuña puede haber servido de bloque rígido (backstop) para el cinturón deformado. El modelamiento gravimetrico no requiere que una corteza oceánica forme el basamento en los cinturones plegados de Sinú y San Jacinto como se ha sugerido previamente. Capas aisladas y tajadas delgadas de sedimentos oceánicos pudieron haber sido rasgadas de la placa entrante y cabalgadas dentro de una melange acrecionaria, y eventualmente expuesta en superficie. La forma de la cuña continental / limite de la corteza oceánica se asemeja a una zona de subducción de bajo ángulo o plana (ángulo ß entre 2º a 3º), y se interpreta aquí como un sobre corrimiento de bajo ángulo del norte de Sur América cabalgando en una dirección altamente oblicua sobre la placa Caribe subyacente. El mapa de basamento en profundidad obtenido durante nuestro estudio forma las bases para estudios de análisis de cuencas, maduración de hidrocarburos y estudios de evolución en la región. A manera de ejemplo, hemos aplicado dicho mapa al análisis flexural del LMB.