共查询到20条相似文献，搜索用时 46 毫秒
1.
Magnetic anomalies of offshore Krishna-Godavari basin,eastern continental margin of India 总被引：1，自引：0，他引：1
K. V. Swamy I. V. Radhakrishna Murthy K. S. Krishna K. S. R. Murthy A. S. Subrahmanyam M. M. Malleswara Rao 《Journal of Earth System Science》2009,118(4):405-412
The marine magnetic data acquired from offshore Krishna-Godavari (K-G) basin, eastern continental margin of India (ECMI),
brought out a prominent NE-SW trending feature, which could be explained by a buried structural high formed by volcanic activity.
The magnetic anomaly feature is also associated with a distinct negative gravity anomaly similar to the one associated with
85°E Ridge. The gravity low could be attributed to a flexure at the Moho boundary, which could in turn be filled with the
volcanic material. Inversion of the magnetic and gravity anomalies was also carried out to establish the similarity of anomalies
of the two geological features (structural high on the margin and the 85°E Ridge) and their interpretations. In both cases,
the magnetic anomalies were caused dominantly by the magnetization contrast between the volcanic material and the surrounding
oceanic crust, whereas the low gravity anomalies are by the flexures of the order of 3–4 km at Moho boundary beneath them.
The analysis suggests that both structural high present in offshore Krishna-Godavari basin and the 85°E Ridge have been emplaced
on relatively older oceanic crust by a common volcanic process, but at discrete times, and that several of the gravity lows
in the Bay of Bengal can be attributed to flexures on the Moho, each created due to the load of volcanic material. 相似文献
2.
K M SREEJITH M RADHAKRISHNA K S KRISHNA T J MAJUMDAR 《Journal of Earth System Science》2011,120(4):605-615
The 85°E Ridge extends from the Mahanadi Basin, off northeastern margin of India to the Afanasy Nikitin Seamount in the Central
Indian Basin. The ridge is associated with two contrasting gravity anomalies: negative anomaly over the north part (up to
5°N latitude), where the ridge structure is buried under thick Bengal Fan sediments and positive anomaly over the south part,
where the structure is intermittently exposed above the seafloor. Ship-borne gravity and seismic reflection data are modelled
using process oriented method and this suggest that the 85°E Ridge was emplaced on approximately 10–15 km thick elastic plate
(Te) and in an off-ridge tectonic setting. We simulated gravity anomalies for different crust-sediment structural configurations
of the ridge that were existing at three geological ages, such as Late Cretaceous, Early Miocene and Present. The study shows
that the gravity anomaly of the ridge in the north has changed through time from its inception to present. During the Late
Cretaceous the ridge was associated with a significant positive anomaly with a compensation generated by a broad flexure of
the Moho boundary. By Early Miocene the ridge was approximately covered by the post-collision sediments and led to alteration
of the initial gravity anomaly to a small positive anomaly. At present, the ridge is buried by approximately 3 km thick Bengal
Fan sediments on its crestal region and about 8 km thick pre- and post-collision sediments on the flanks. This geological
setting had changed physical properties of the sediments and led to alter the minor positive gravity anomaly of Early Miocene
to the distinct negative gravity anomaly. 相似文献
3.
4.
龙门山均衡重力异常及其对青藏高原东缘山脉地壳隆升的约束 总被引：16，自引：0，他引：16
青藏高原东缘处于不均衡状态，自西而东可分为青藏高原弱负均衡重力异常区、龙门山正均衡重力异常区和四川盆地负均衡重力异常区，表明该区的不均衡状态并未导致Airy均衡运动的产生，即龙门山没有均衡下降，而处于不断的隆升状态，显示该地区反均衡运动的构造抬升是导致龙门山隆升的主因。本次采用似三度体重力异常计算方法对该区的正均衡重力异常进行模拟和反演，研究了大尺度地貌分异与均衡重力异常分区之间的相互关系，结果表明，龙门山的下地壳顶面抬升了11．2～12．6km，造成了龙门山的正均衡异常，揭示了构造抬升和剥蚀作用在相似的时间尺度上和空间尺度上控制着龙门山地貌的形成，龙门山的表面隆升是构造隆升和剥蚀作用相叠加的产物。 相似文献
5.
奇异值分解(singular value decomposition,SVD)和二维经验模型分解(bi-dimensional empirical mode decomposition,BEMD)2种方法用于鲁西铜石金矿田的金矿化致矿重力异常提取.通过对比研究得出如下结论:①基于重力数据,由BEMD和SVD 2种方法获... 相似文献
6.
Satellite Gravity Anomalies and Their Correlation with the Major Tectonic Features in the South China Sea 总被引：4，自引：0，他引：4
The South China Sea (SCS) is a region of interaction among three major plates: the Pacific, Indo-Australian and Eurasian. The collision of the Indian subcontinent with the Eurasian plate in the northwest, back-arc spreading at the center, and subduction beneath the Philippine plate along Manila trench in the east and the collision along Palawan trough in the south have produced complex tectonic features within and along the SCS. This investigation examines the satellite-derived gravity anomalies of the SCS and compares them with major tectonic features of the area. A map of Bouguer gravity anomaly is derived in conjunction with available seafloor topography to investigate the crustal structure. The residual isostatic gravity anomaly is calculated assuming that the Cenozoic sedimentary load is isostatically compensated. The features in the gravity anomalies in general correlate remarkably well with the major geological features, including offsets in the seafloor spreading segments, major faults, basins, seamounts and other manifestations of magmatism and volcanism on the seafloor. They also correlate with the presumed location of continental-oceanic crust boundary. The region underlain by oceanic crust in the central part of the SCS is characterized by a large positive Bouguer gravity anomaly (220–330 mgal) as well as large free-air and residual isostatic anomalies. There are, however, important differences among spreading segments. For example, in terms of free-air gravity anomaly, the southwest section of mid-ocean has an approximately 50 km wide belt of gravity low superimposed on a broad high of 45 mgal running NW–SE, whereas there are no similar features in other spreading segments. There are indications that gravity anomalies may represent lateral variation in upper crustal density structure. For instance, free air and isostatic anomalies show large positive anomalies in the east of the Namconson basin, which coincide with areas of dense volcanic material known from seismic surveys. The Red River Fault system are clearly identified in the satellite gravity anomalies, including three major faults, Songchay Fault in the southwest, Songlo Fault in the Northeast and Central Fault in the center of the basin. They are elongated in NW–SE direction between 20±30'N and 17°N and reach to Vietnam Scarp Fault around 16°30'N. It is also defined that the crustal density in the south side of the Central Basin is denser than that in the north side of the Central Basin. 相似文献
7.
通过对典型活动断裂两盘重力场特征的对比与分析,发现具有大面积布各重力负异常（或相对我异常）的地块总是向赤道方向运动,而布格重力正异常（或相对正异常）的地块向极点方向运动,布格重力异常图反映了密度情况,正异常带为大密度地块,负异常带为小密度地块,从理论分析得知,地块的密度变化导致了受力条件的改变,致使地块失稳产生运动,岩浆活动是造成地块密度变化的重要因素。 相似文献
8.
甘肃白银厂铜多金属硫化物矿田是受陆缘弧环境火山机构及其同生断裂控制的典型火山岩赋矿块状硫化物矿床(VHMS)。为了进一步探讨该矿床重磁场特征及与构造和矿床的关系,通过对区内的重磁场异常数据进行位场分离、小波分析和基于张量数据的三维欧拉反褶积自动确定地质体位置和埋藏深度的定量反演计算。结果表明,研究区布格重力场具有西部高、东部低的特征,其磁场可划分为4个磁场区;局部异常按一定分布规律呈圆形或似圆形正负相间分布,不同尺度的重磁细节异常图在一定程度上反映出引起重磁异常的地质异常体具有一定的延深且分布稳定,而且这些地质异常体具有向深部复合的趋势。经位场分离后正负相间的剩余重磁异常分布范围和分布特征大致反映了白银厂奥陶纪中酸性火山岩建造构造为一个继承性的火山穹窿构造,东、西部不同的重磁异常特征说明东西部的火山喷发具有不同的基底、源区和喷发方式。发育NW向、NE向、近NS向、NEE向等4组断裂构造,近NS向断裂F3、F4、F5、F6、F7形成时间稍晚于NEE向断裂,其与NEE向断裂F1、F2共同形成了研究区棋盘网格状的构造分布特征,这两组断裂为研究区内主要的控岩、控矿断裂。火山机构的分布明显受断裂构造控制,火山口集中分布在深大断裂、大断裂或两组断裂的交汇处。矿田内各矿床及成矿有利地段均处于研究区中部低缓重磁异常场内正负磁异常变化的梯度带内。本次研究为控矿要素研究和开展找矿预测工作提供了丰富、翔实的地球物理资料。 相似文献
9.
K. Hinz H.-U. Schlüter A.C. Grant S.P. Srivastava D. Umpleby J. Woodside 《Tectonophysics》1979,59(1-4)
In 1977 the Federal Institute for Geosciences and Natural Resources, Hannover, carried out a large scale multichannel reflection seismic survey in the Labrador Sea. This survey provided an opportunity for the direct comparison of the geologic structure of the Labrador and Greenland margins. The seismic records across the Labrador Shelf show a thick, prograding sedimentary wedge consisting of several seismic sequences onlapping an acoustic basement that dips steeply seaward. The surface of the acoustic basement is irregular below the continental slope, indicating Late Cretaceous—Early Tertiary faulting. The thick sedimentary section below the slope is divided by an unconformity, tentatively identified as Late Tertiary in age, into two seismic megasequencies which can be subdivided. The acoustic basement on the Greenland side is also strongly faulted but is overlain, in the south, by a thin sedimentary section. The sediment cover thickens on the Greenland Shelf to the north as the shelf becomes wider.As with more southerly parts of the western Atlantic margin, a positive free-air anomaly (30–50 mgal) lies landward of the shelf break off Labrador and a smaller negative anomaly follows the base of the slope. Similar, but generally narrower features are observed along the Greenland margin. West of the negative anomaly off the Greenland slope a narrow band of lower amplitude positive anomalies tends to be associated with an acoustic basement high observed in the reflection profiles. A landward negative gradient in the simple Airy isostatic anomaly across this margin suggests that the ocean—continent boundary is related to this high.Detailed magnetic measurements across the northern Labrador margin show that well-developed oceanic anomalies trending north-northwest lie east of the large Labrador Shelf gravity high, beyond the 2000 m isobath. Landward of these magnetic anomalies is a quiet magnetic zone within which the linear gravity high is parallel to the shelf break and correlates with a deep, sediment-filled basin. It is inferred that oceanic-type crust or greatly-attenuated continental crust underlies this basin and that continental crust thickens markedly westward of the gravity high over a distance of about 50 km. 相似文献
10.
The nature and origin of the subsurface 85°E Ridge in the Bay of Bengal has remained enigmatic till date despite several theories proposed by earlier researchers. We reinterpreted the recently acquired high quality multichannel seismic reflection data over the northern segment of the ridge that traverses through the Mahanadi offshore, Eastern Continental Margin of India and mapped the ridge boundary and its northward continuity. The ridge is characterized by complex topography, multilayer composition, intrusive bodies and discrete nature of underlying crust. The ridge is associated with large amplitude negative magnetic and gravity anomalies. The negative gravity response across the ridge is probably due to emplacement of relatively low density material as well as ∼2–3 km flexure of the Moho. The observed broad shelf margin basin gravity anomaly in the northern Mahanadi offshore is due to the amalgamation of the 85°E Ridge material with that of continental and oceanic crust. The negative magnetic anomaly signature over the ridge indicates its evolution in the southern hemisphere when the Earth’s magnetic field was normally polarized. The presence of ∼5 s TWT thick sediments over the acoustic basement west of the ridge indicates that the underlying crust is relatively old, Early Cretaceous age.The present study indicates that the probable palaeo-location of Elan Bank is not between the Krishna–Godavari and Mahanadi offshores, but north of Mahanadi. Further, the study suggests that the northern segment of the 85°E Ridge may have emplaced along a pseudo fault during the Mid Cretaceous due to Kerguelen mantle plume activity. The shallow basement east of the ridge may have formed due to the later movement of the microcontinents Elan Bank and Southern Kerguelen Plateau along with the Antarctica plate. 相似文献
11.
庐枞火山岩盆地及其外围重、磁场特征 总被引：9，自引：5，他引：4
为探测长江中下游成矿带庐江-枞阳白垩纪火山岩盆地的深部构造和地壳结构,2007年初在庐枞火山岩盆地进行了以深反射地震剖面探测为主的,新一轮重力、磁力和大地电磁剖面测量。作者在前人研究的基础上对庐枞火山岩盆地及其外围重、磁场特征进行了研究。作者首先分析长江中下游地区重、磁场的分布特征,然后以区域重、磁场特征为背景来认识庐枞地区重、磁场的分布特征。研究各类地质体的物性参数是开展地球物理解释的前提,文中收集并分析了前人对庐枞地区的岩石物性的较为系统研究成果。为了提取重、磁异常的特征,文中对重、磁异常进行了位场转换和图像处理。利用新的深反射地震剖面探测和大地电磁剖面研究成果,采用定性和定量解释方法对庐枞地区重、磁场的分布特征进行了研究并提出新的认识。庐枞火山岩盆地深部存在隐伏的磁性强的中碱性岩类是产生区域磁异常的主要原因。庐枞火山岩盆地下部火成岩所侵入的地层向盆地东南方向延伸,盆地的西北边界向东南方向倾斜。而在罗河断裂带以西没有火成岩存在。亦即庐枞火山岩盆地是一个沿北东向罗河断裂向东发育的非对称火山盆地。另外,在庐枞火山岩盆地西部边缘罗河深部存在切穿莫霍面的断裂带沿北东向延展数十千米。 相似文献
12.
《Journal of South American Earth Sciences》1999,12(1):87-98
Flexural modeling of bending of the southern and southeastern borders of the Amazon lithospheric plate under the western border of the Goiás Massif and western Parnaı́ba basin was constrained by 1070 gravity stations between 5°–14°S and 46°–52.5°W. Topography and aeromagnetic data were also used to estimate the loads of the Araguaia thrust belt. A sequence of Bouguer gravity anomaly lows (−80 to −40 mGal) is located over the Araguaia thrust belt and Cenozoic sediments of the Ilha do Bananal basin. Bouguer anomalies over the Amazon craton, to the west of the thrust belt, are higher than −20 mGal. Towards the east, over the Goiás Massif, the São Francisco craton and the Paleozoic to Mesozoic Parnaı́ba basin, anomalies range from −70 to −20 mGal. Comparison between topography and gravity along profiles perpendicular to the cratonic borders and across the Araguaia thrust belt shows that the long-wavelength gravity anomalies are best explained by bending of the Amazon plate caused by loads such as the observed topography, the thrust-sheets of the Araguaia belt and the remnants of ancient island-arc system in the Goiás massif. The thickness of the Araguaia thrust belt together with the Cenozoic sediments was estimated using aeromagnetic data and it ranges from 6 to 8 km. This load was used to calculate the minimum effective elastic thickness Te for the Amazon plate. Te=80 km was estimated by comparing the observed Bouguer anomalies with the gravity anomalies caused by bending of the crust-mantle interface of a broken elastic plate model. These results support the proposition that the Araguaia belt formed during the collision and suture of the Amazon and the São Francisco lithospheric plates, in late Proterozoic times. 相似文献
13.
《International Geology Review》2012,54(14):1744-1762
The European Cenozoic Rift System hosts major temperature anomalies in Central Europe. In its central segment, the Upper Rhine Graben (URG), temperatures range from 75°C to nearly 150°C at a depth of 2000 m. Different hypotheses have been suggested to explain the localization of these anomalies. Our review and comprehensive interpretation of gravimetric and magnetic data, as well as neotectonic activity patterns, suggests that low-density, mostly magnetic and fractured granitic basement is systematically associated with major temperature anomalies. Further analyses provide insight into different heat transport processes contributing to the localization of these anomalies. Magnetic and gravity anomalies are known to represent lithological variations associated with the pre-Permian. We show their spatial relationship with positive temperature anomalies in the URG. Correlation between magnetics and temperature reveal a mean contribution of heat production to the temperature anomaly of about 10–15°C. A slightly higher mean value is obtained from correlation between gravity and temperature, which may be attributed to effects resulting from fracture porosity. The spatial relationship between temperature anomalies and neotectonic patterns indicates compressional shear and uplift regime for the major anomalies of the central segment of the URG. This is in agreement with different numerical models indicating free convection on fracture zones linked to faults. Our findings show that about 15–25% of the temperature anomaly can be attributed to variation in heat production. Hydrothermal circulation convection along faults, activated by the tectonic context, may explain the remaining 75–85% of the temperature anomalies. 相似文献
14.
《International Geology Review》2012,54(4):689-695
The Magnitogorsk synclinorium, a major structure of the southern Urals, has pronounced positive gravity anomalies associated with numerous greenstone intrusives. It is bounded on the west by a gravity low which corresponds with the Ural-Tau and Bashkir anticlinorium and on the east by gravity minima corresponding to the East-Uralian anticlinorium with its numerous intrusives. The relationship between gravity anomalies and major south Uralian structure indicates the effect of deeper structure conditions. Magnetic data correlates with the gravity results in that the western and eastern zones have quiescent negative magnetic fields and the Magnitogorsk synclinorium shows a strongly differentiated magnetic field. Positive magnetic anomalies are related to ultrabasic and basic intrusives, though some large magnetic maxima correspond to lower Carboniferous acidic and alkalic intrusives. Gravity and magnetic anomalies give some idea of deeper structure of the area. Copper pyrite deposits are associated with linear magnetic anomalies and associated zones of crushing. Regionally, these deposits are definitely associated with positive gravity anomaly zones. Geologic and geophysical maps are included, showing major geologic features and related magnetic and gravity anomaly zones. — C. E. Sears. 相似文献
15.
The driving force for the basin subsiding against isostatic balance in and around Lake Biwa in the Kinki district, Japan is discussed. The lake region is characterized by strong negative Bouguer anomalies, especially by a steep horizontal gradient zone of gravity anomaly running along the western margin of the lake. The large negative anomaly (>50 mgal) cannot be explained by low-density sediments beneath it. A down-warping structure extending to the Moho depth should be taken into account. This conjecture has been strongly supported by a short-period receiver function imaging, which shows a clear offset of about 8 km for the Moho discontinuity under the steep gravity gradient zone.A question arises as to what is the driving force to create such a large down-warping structure. We consider that the subduction of the shallow-dipping slab under the region (Philippine Sea Slab) may cause crustal deformation by dragging the viscous mantle downward. In order to verify this model, we simulated the induced mantle flow due to the subduction of the Philippine Sea Slab and the pressure distribution on the crust–mantle boundary. This numerical experiment showed that the induced flow makes a strong negative pressure zone under the lake region if the slab has a vertical offset along the direction of subduction. This offset of the slab is consistent with plate models deduced from hypocentral distributions and Sp phases of the deep-focus earthquakes. 相似文献
16.
利用重力梯度反演南海西南海盆深部构造 总被引：2，自引：0，他引：2
重力梯度异常反映的是重力异常的变化,其分辨率比重力异常高。重力梯度空间参量图能给出构造倾角和倾面的信息,结合重力梯度剖面和梯度空间参量图可以构建出地下构造的几何模型,进而对一些复杂构造进行解释。本文利用重力梯度异常对南海西南海盆进行了解释,得到大致以西南海盆北东向扩张轴为对称轴的穹隆状构造面。该构造面在西南海盆下6~15km处形成一个密度界面,此界面可能是西南海盆北西-南东向海底扩张期间地幔上隆所引起的。 相似文献
17.
Seismic ray direction anomalies and relative residuals of earthquakes recorded at Gauribidanur array
Slowness and azimuthal anomalies provide valuable information about lateral inhomogeneities within the crust and mantle of the earth. Over 300 earthquakes (distance range 14°–36° and azimuth 0°–360°) recorded at Gauribidanur seismic array (GBA) in southern India, were analysed using adaptive processing techniques. Slowness anomalies upto 1·3 sec/deg and azimuthal anomalies upto 8° have been observed in the present analysis. Slowness anomaly patterns for Java trench, Mid-Indian oceanic ridge earthquakes are more consistent as compared to the events originating in the Himalayan and Hindukush regions. A significant feature of the azimuthal anomaly pattern was the distinct absence of any positive anomalies from earthquakes occurring in mid-oceanic ridge. These anomalies have also been analysed as a function of epicentral distance and are mainly attributed to the transition zones occurring between 400–700 km depth ranges in the Indian upper mantle regions. Relative residuals between the stations of GBA have very little dependence on azimuth and distance. An anomalous structure beneath the array in the direction of the Java trench region (azimuth 116–126°) has been postulated on the basis of large systematic slowness vectors observed. 相似文献
18.
Detailed gravity data integrated with geological data and mining well data are analysed to constrain the shape of the Triassic evaporitic body at Jebel El Mourra (northern Tunisian Atlas) and the mechanism of its emplacement at the surface. The gravity data analysis included the construction of a gravity anomaly maps, and synthetic and forward 2.5D gravity models. The complete Bouguer and residual gravity anomaly maps indicate a positive amplitude gravity anomaly over the Triassic evaporitic outcrops and prominent NE–SW‐trending features associated with the boundary of the Triassic rocks and surrounded layers. A NW–SE‐trending gravity model that crosses the Triassic evaporitic outcrop at Jebel El Mourra shows that the positive gravity anomaly can be explained by a deep‐rooted salt diapir. Conventional models of salt dome formation suggest that they produce negative gravity anomalies; however, this study shows that this model is not universal. The studied area is an example of a diapir expressed by positive gravity anomaly and this result is supported by synthetic gravity models at different stages of salt piercing. 相似文献
19.
《China Geology》2021,4(4):553-570
The southern part of the Kyushu-Palau Ridge (KPR) is located at the conjunction of the West Philippine Basin, the Parece Vela Basin, the Palau Basin, and the Caroline Basin. This area has extremely complex structures and is critical for the research on the tectonic evolution of marginal seas in the Western Pacific Ocean. However, only few studies have been completed on the southern part, and the geophysical fields and deep structures in this part are not well understood. Given this, this study finely depicts the characteristics of the gravity and magnetic anomalies and extracts information on deep structures in the southern part of the KPR based on the gravity and magnetic data obtained from the 11th expedition of the deep-sea geological survey of the Western Pacific Ocean conducted by the Guangzhou Marine Geological Survey, China Geological Survey using the R/V Haiyangdizhi 6. Furthermore, with the data collected on the water depth, sediment thickness, and multichannel seismic transects as constraints, a 3D density model and Moho depths of the study area were obtained using 3D density inversion. The results are as follows. (1) The gravity and magnetic anomalies in the study area show distinct zoning and segmentation. In detail, the gravity and magnetic anomalies to the south of 11°N of the KPR transition from high-amplitude continuous linear positive anomalies into low-amplitude intermittent linear positive anomalies. In contrast, the gravity and magnetic anomalies to the north of 11°N of the KPR are discontinuous and show alternating positive and negative anomalies. These anomalies can be divided into four sections, of which the separation points correspond well to the locations of deep faults, thus, revealing different field-source attributes and tectonic genesis of the KPR. (2) The Moho depth in the basins in the study area is 6–12 km. The Moho depth in the southern part of KPR show segmentation. Specifically, the depth is 10–12 km to the north of 11°N, 12–14 km from 9.5°N to 11°N, 14–16 km from 8.5°N to 9.5°N, and 16–25 km in the Palau Islands. (3) The KPR is a remnant intra-oceanic arc with the oceanic-crust basement.which shows noticeably discontinuous from north to south in geological structure and is intersected by NEE-trending lithospheric-scale deep faults. With large and deep faults F3 and F1 (the Mindanao fault) as boundaries overall, the southern part of the KPR can be divided into three zones. In detail, the portion to the south of 8.5°N (F3) is a tectonically active zone, the KPR portion between 8.5°N and 11°N is a tectonically active transition zone, and the portion to the north of 11°N is a tectonically inactive zone. (4) The oceanic crust in the KPR is slightly thicker than that in the basins on both sides of the ridge, and it is inferred that the KPR formed from the thickening of the oceanic crust induced by the upwelling of deep magma in the process of rifting of remnant arcs during the Middle Oligocene. In addition, it is inferred that the thick oceanic crust under the Palau Islands is related to the constant upwelling of deep magma induced by the continuous northwestward subduction of the Caroline Plate toward the Palau Trench since the Late Oligocene. This study provides a scientific basis for systematically understanding the crustal attributes, deep structures, and evolution of the KPR.©2021 China Geology Editorial Office. 相似文献
20.
The decrease of density contrast with depth in sedimentary basins is approximated by an exponential function. The anomaly
equation, in frequency domain, of a prismatic model with an exponential density function is derived. The method has been extended
to derive the Fourier transforms of the gravity anomalies of the sedimentary basin, wherein the basin is viewed as vertical
prisms placed in juxtaposition. The gravity anomalies of the sedimentary basin are obtained by taking the inverse Fourier
transforms. Filon’s method has been extended for calculating accurate inverse Fourier transforms. The accuracy of the method
has been tested using a synthetic example. A combination of space and frequency domain methods have been developed for inversion
of gravity anomalies over the sedimentary basin. The method has been applied to interpret one synthetic profile and one field
profile over the Godavari basin. The method developed in this paper to calculate the inverse Fourier transforms yields continuous
spectrum with accurate values. The maximum depth deduced from the gravity anomalies is of the same order as the depth encountered
to the basement at the Aswaraopeta borewell. 相似文献