共查询到20条相似文献，搜索用时 46 毫秒
1.
K. Crane E. Sundvor J. -P. Foucher M. Hobart A. M. Myhre S. LeDouaran 《Marine Geophysical Researches》1988,9(2):165-194
The northern Norwegian-Greenland Sea opened up as the Knipovich Ridge propagated from the south into the ancient continental Spitsbergen Shear Zone. Heat flow data suggest that magma was first intruded at a latitude of 75° N around 60 m.y.b.p. By 40–50 m.y.b.p. oceanic crust was forming at a latitude of 78° N. At 12 m.y.b.p. the Hovgård Transform Fault was deactivated during a northwards propagation of the Knipovich Ridge. Spreading is now in its nascent stages along the Molloy Ridge within the trough of the Spitsbergen Fracture Zone. Spreading rates are slower in the north than the south. For the Knipovich Ridge at 78° N they range from 1.5–2.3 mm yr-1 on the eastern flank to 1.9–3.1 mm yr-1 on the western flank. At a latitude of 75° N spreading rates increase to 4.3–4.9 mm yr-1.Thermal profiles reveal regions of off-axial high heat flow. They are located at ages of 14 m.y. west and 13 m.y. east of the northern Knipovich Ridge, and at 36 m.y. on the eastern flank of the southern Knipovich Ridge. These may correspond to episodes of increased magmatic activity; which may be related to times of rapid north-wards rise axis propagation.The fact that the Norwegian-Greenland Sea is almost void of magnetic anomalies may be caused by the chaotic extrusion of basalts from a spreading center trapped within the confines of an ancient continental shear zone. The oblique impact of the propagating rift with the ancient shear zone may have created an unstable state of stress in the region. If so, extension took place preferentially to the northwest, while compression occurred to the southeast between the opening, leaking shear zone and the Svalbard margin. This caused faster spreading rates to the northwest than to the southeast. 相似文献
2.
The Yermak Plateau, bordering the Arctic Ocean and the Norwegian-Greenland Sea, and adjacent to the continental Svalbard Archipelago, is characterized by high heat flow relative to its surrounding region. South of and parallel to the trend of the plateau lies the formerly active-Spitsbergen Shear Zone (De Geer Zone), which is now occupied by the slowly spreading Knipovich and Molloy Ridges. An analysis of these heat flow data suggest that asymmetric spreading within the Norwegian-Greenland Sea propagated northwards along one of the faults associated with the Spitsbergen Shear Zone. The broad zone of faults, once associated with this paleo-shear zone, extends throughout Svalbard as well as on and to the west of the Knipovich Ridge. This network of faults may comprise a complex system of detachment surfaces along which magma may rise from a deep-seated source and across which simple shear extension may develop. Dike injection into the Yermak Plateau, north of the propagating ridge may have been initiated by the thermal response of the highly fractured lithosphere to this propagating asthenospheric front. We suggest that one of these faults, acting as a secondary detachment to the main fault underlying the Knipovich Ridge, may be dissecting the Yermak Plateau. Based on an analysis of the thermal data, simple shear extension may have been taking place along a broad zone of intrusion. This region has undergone and is probably still undergoing thermal rejuvenation. Multiple zones of intrusion may be a common phenomena along newly rifted continental margins especially when they have been substantially faulted prior to rifting. 相似文献
3.
Jörn Thiede Stephanie Pfirman Hans-Werner Schenke Wolfgang Reil 《Marine Geophysical Researches》1990,12(3):197-214
The sea floor of Fram Strait, the over 2500 m deep passage between the Arctic Ocean and the Norwegian-Greenland Sea, is part of a complex transform zone between the Knipovich mid-oceanic ridge of the Norwegian-Greenland Sea and the Nansen-Gakkel Ridge of the Arctic Ocean. Because linear magnetic anomalies formed by sea-floor spreading have not been found, the precise location of the boundary between the Eurasian and the North American plate is unknown in this region. Systematic surveying of Fram Strait with SEABEAM and high resolution seismic profiling began in 1984 and continued in 1985 and 1987, providing detailed morphology of the Fram Strait sea floor and permitting better definition of its morphotectonics. The 1984 survey presented in this paper provided a complete set of bathymetric data from the southernmost section of the Svalbard Transform, including the Molloy Fracture Zone, connecting the Knipovich Ridge to the Molloy Ridge; and the Molloy Deep, a nodal basin formed at the intersection of the Molloy Transform Fault and the Molloy Ridge. This nodal basin has a revised maximum depth of 5607 m water depth at 79°8.5N and 2°47E. 相似文献
4.
The rift zone??s relief, the spreading kinematics, and the experimental modeling of the Knipovich Ridge??s formation were analyzed. Its rift zone is formed in a transtension environment. Faulting is predominant in its northern part, while strike-slip is characteristic for the south. A system of short extension basins connected by deep strike-slip U-shaped troughs is observed in the south. A system of volcanic rises connected by short shallow basins is observed in the north. The rift valley is V-shaped. According to the experimental modeling data, these extension kinematics provide the formation of short extension basins connected by strike-slips and transtension faults. Their length and orientation depend on the spreading obliquity of each segment. 相似文献
5.
2D multichannel seismic data and bathymetric records from the glaciated western Svalbard margin and the rift valley region of the ultraslow, and oblique-spreading, Knipovich Ridge are in this study interpreted to infer differences in seafloor spreading mechanisms and to identify sedimentary processes. Our results show that the rift flank geometry, the rift valley elevation and the active magmatism are closely linked. The inferred magmatic segments of the Knipovich Ridge exhibit high and steep rift flanks, whereas the rift flank heights of the proposed tectonic-dominated segments are lower and less steep. In addition, we observe significant rift flank asymmetry across the rift valley which can be partly explained by subsidence due to sediment loading. The identification of a huge sedimentary wedge on the western rift flank suggests that the oldest parts of these sediments have been transported from the western Svalbard margin and across the rift valley. However, we suggest that most of these sediments are glacimarine/hemipelagic sediments which have been deposited in the time period after the rift valley flanks had developed sufficiently to cut off the direct transport routes from the western Svalbard margin. We also observe thick current depositions on the western side, suggesting a strong along-slope influence of the West Spitsbergen Current during the Plio–Pleistocene time period. 相似文献
6.
Sufyan Sub-basin is an East-West trending Sub-basin located in the northwestern part of the Muglad Basin (Sudan), in the eastern extension of the West and Central Africa Rift System (WCARS). The trend of the Sufyan Sub-basin (E-W) is different from the general trend of Muglad Basin (NW-SE) and similar to Baggara basin in the west of Sudan and other basins in east Chad. The unique E-W trend, suggests that this Sub-basin originated by a mechanism different from Muglad Basin that is considered more extensional in origin. Five regional seismic lines are included to illustrate the structural and stratigraphic variation across the Sub-basin. Fault polygons maps for six horizons, four isopach maps, five cross-sections, and two associated kinematic models are presented in this study. Sufyan Sub-basin is characterized by rhombic geometry with three boundary faults; two of those faults exhibit dextral strike slip movement, with two depocenters at the western and eastern segments of the southern fault. Structural interpretation of Sufyan Sub-basin based on 2D seismic data highlights the style of strike-slip related structure. Negative flower structures, en-echelon faults, and rhombic geometry all suggest a significant component of a pull-apart transtensional movement in Sufyan Sub-basin. Other alternative scenarios for evolutionary history and the forming mechanism were introduced such as the oblique extension model. The Sufyan Sub-basin is believed to be highly affected by the Central African Shear Zone (CASZ). In this study, several transtension and oblique rift related features interpreted from Bouguer gravity map and seismic data are briefly described and illustrated. Based on this study, the favorable areas for hydrocarbon accumulation are the areas of flower structure and the areas that near to the two depocenters that controlled by the southern boundary fault. 相似文献
7.
The right-lateral Blanco Transform Fault Zone (BTFZ) offsets the Gorda and the Juan de Fuca Ridges along a 350 km long complex zone of ridges and right-stepping depressions. The overall geometry of the BTFZ is similar to several other oceanic transform fault zones located along the East Pacific Rise (e.g., Siquieros) and to divergent wrench faults on continents; i.e., long strike-slip master faults offset by extensional basins. These depressions have formed over the past 5 Ma as the result of continual reorientation of the BTFZ in response to changes in plate motion. The central depression (Cascadia Depression) is flanked by symmetrically distributed, inward-facing back-tilted fault blocks. It is probably a short seafloor spreading center that has been operating since about 5 Ma, when a southward propagating rift failed to kill the last remnant of a ridge segment. The Gorda Depression on the eastern end of the BTFZ may have initially formed as the result of a similar occurrence involving a northward propagating rift on the Gorda ridge system. Several of the smaller basins (East Blanco, Surveyor and Gorda) morphologically appear to be oceanic analogues of continental pull-apart basins. This would imply diffuse extension rather than the discrete neovolcanic zone associated with a typical seafloor spreading center. The basins along the western half of the BTFZ have probably formed within the last few hundred thousands years, possibly as the result of a minor change in the Juan de Fuca/Pacific relative motion. 相似文献
8.
9.
On the Mid-Atlantic Ridge (MAR) from 34°–35.5° S, three ridge segments span the 108 km distance between the Meteor Fracture Zone (FZ) and the Montevideo FZ. Each of these segments is perpendicular to the adjoining transforms. Magnetic isochrons in the southern half of the region are oblique to the spreading direction and are offset from the morphological expression of the plate boundary, revealing a transition from oblique to orthogonal spreading within the last 750,000 years. Changes in orientation and cross-sectional form of the rift valley, as modified by tectonic processes, are preserved in the off-axis abyssal-hill fabric. We present a new statistical method for describing size and orientation of abyssal hills based on local slopes. For a given offset, the range of sorted slopes from the first to third quartile provides a robust estimate of topographic variability. The variability can be parametrized by azimuthal direction, plan-view aspect ratio, characteristic height and width. We resolve lineation azimuth within 6°, and characteristic height, width and aspect ratio within 20–30%, using 18 by 21 km sample boxes crossed by multiple Sea Beam swaths covering approximately 30% of the box. In the northern portion of the survey, the azimuth is mainly ridge parallel, while in the southern portion, the azimuth rotates 23° clockwise from ridge strike. Characteristic height and width are greater in the southern half than in the northern half, while aspect ratios are lower. The asymmetry of quartiles about the median slope provides evidence that inward-facing normal faults bounding the rift valley are a significant source of topography. Fabric disrupted by migration of small-offset discontinuities has higher than average characteristic height. Characteristic height and width correlate positively with residual gravity, an indicator of crustal thinning. A residual gravity low, possibly the current focus of upwelling, coincides with a newly formed spreading axis. These correlations suggest that evolution of ridge geometry can be controlled by crust and mantle thermal structure. Either variation in magma supply, resulting in changes in stress normal to the ridge axis, or a major realignment of the Montevideo Transform, temporarily resulting in increased shear stress across newly activated faults, may have been responsible for changes in orientation and morphology of the spreading center. 相似文献
10.
Ingrid Marie Hasle Amundsen Maria Blinova Berit Oline Hjelstuen Rolf Mjelde Haflidi Haflidason 《Marine Geophysical Researches》2011,32(4):441-453
The northeastern high-latitude North Atlantic is characterised by the Bellsund and Isfjorden fans on the continental slope
off west Svalbard, the asymmetrical ultraslow Knipovich spreading ridge and a 1,000 m deep rift valley. Recently collected
multichannel seismic profiles and bathymetric records now provide a more complete picture of sedimentary processes and depositional
environments within this region. Both downslope and alongslope sedimentary processes are identified in the study area. Turbidity
currents and deposition of glacigenic debris flows are the dominating downslope processes, whereas mass failures, which are
a common process on glaciated margins, appear to have been less significant. The slide debrite observed on the Bellsund Fan
is most likely related to a 2.5–1.7 Ma old failure on the northwestern Barents Sea margin. The seismic records further reveal
that alongslope current processes played a major role in shaping the sediment packages in the study area. Within the Knipovich
rift valley and at the western rift flank accumulations as thick as 950–1,000 m are deposited. We note that oceanic basement
is locally exposed within the rift valley, and that seismostratigraphic relationships indicate that fault activity along the
eastern rift flank lasted until at least as recently as 1.5 Ma. A purely hemipelagic origin of the sediments in the rift valley
and on the western rift flank is unlikely. We suggest that these sediments, partly, have been sourced from the western Svalbard—northwestern
Barents Sea margin and into the Knipovich Ridge rift valley before continuous spreading and tectonic activity caused the sediments
to be transported out of the valley and westward. 相似文献
11.
Jean-Christophe Sempéré Jian Lin Holly S. Brown Hans Schouten G. M. Purdy 《Marine Geophysical Researches》1993,15(3):153-200
Analysis of Sea Beam bathymetry along the Mid-Atlantic Ridge between 24°00 N and 30°40 N reveals the nature and scale of the segmentation of this slow-spreading center. Except for the Atlantis Transform, there are no transform offsets along this 800-km-long portion of the plate boundary. Instead, the Mid-Atlantic Ridge is offset at intervals of 10–100 km by nontransform discontinuities, usually located at local depth maxima along the rift valley. At these discontinuities, the horizontal shear between offset ridge segments is not accommodated by a narrow, sustained transform-zone. Non-transform discontinuities along the MAR can be classified according to their morphology, which is partly controlled by the distance between the offset neovolcanic zones, and their spatial and temporal stability. Some of the non-transform discontinuities are associated with off-axis basins which integrate spatially to form discordant zones on the flanks of the spreading center. These basins may be the fossil equivalents of the terminal lows which flank the neovolcanic zone at the ends of each segment. The off-axis traces, which do not lie along small circles about the pole of opening of the two plates, reflect the migration of the discontinuities along the spreading center.The spectrum of rift valley morphologies ranges from a narrow, deep, hourglass-shaped valley to a wide valley bounded by low-relief rift mountains. A simple classification of segment morphology involves two types of segments. Long and narrow segments are found preferentially on top of the long-wavelength, along-axis bathymetric high between the Kane and Atlantis Transforms. These segments are associated with circular mantle Bouguer anomalies which are consistent with focused mantle upwelling beneath the segment mid-points. Wide, U-shaped segments in cross-section are preferentially found in the deep part of the long-wavelength, along-axis depth profile. These segments do not appear to be associated with circular mantle Bouguer anomalies, indicating perhaps a more complex pattern of mantle upwelling and/or crustal structure. Thus, the long-recognized bimodal distribution of segment morphology may be associated with different patterns of mantle upwelling and/or crustal structure. We propose that the range of observed, first-order variations in segment morphology reflects differences in the flow pattern, volume and temporal continuity of magmatic upwelling at the segment scale. However, despite large first-order differences, all segments display similar intra-segment, morphotectonic variations. We postulate that the intra-segment variability represents differences in the relative importance of volcanism and tectonism along strike away from a zone of enhanced magma upwelling within each segment. The contribution of volcanism to the morphology will be more important near the shallowest portion of the rift valley within each segment, beneath which we postulate that upwelling of magma is enhanced, than beneath the ends of the segment. Conversely, the contribution of tectonic extension to the morphology will become more important toward the spreading center discontinuities. Variations in magmatic budget along the strike of a segment will result in along-axis variations in crustal structure. Segment mid-points may coincide with regions of highest melt production and thick crust, and non-transform discontinuities with regions of lowest melt production and thin crust. This hypothesis is consistent with available seismic and gravity data.The rift valley of the Mid-Atlantic Ridge is in general an asymmetric feature. Near segment mid-points, the rift valley is usually symmetric but, away from the segment mid-points, one side of the rift valley often consists of a steep, faulted slope while the other side forms a more gradual ramp. These observations suggest that half-grabens, rather than full-grabens, are the fundamental building blocks of the rift valley. They also indicate that the pattern of faulting varies along strike at the segment scale, and may be a consequence of the three-dimensional, thermo-mechanical structure of segments associated with enhanced mantle upwelling beneath their mid-points. 相似文献
12.
Simrad EM12 backscatter strength data of the Southwest Indian Ridge (SWIR), between 57°E and 70°E, are used to reveal the along-axis segmentation of this super slow-spreading ridge. The backscatter properties of different geologic domains, like bathymetric highs and oblique basins within the rift valley, are characterized using 66 small test sites. We show that backscatter strength is higher on bathymetric swells, corresponding to segment centres, and lower in deep oblique basins corresponding to axial non-transform discontinuities and fracture zones. This contrast between segment centres and discontinuities is produced by both a thicker sediment cover and less frequent volcanic eruptions at segment ends. Using the model of Mitchell (1993), sediments have been estimated to be 2 to 5 m thicker in these areas than at segment centres. The distribution of the seamounts within the rift valley is controlling the long-wavelength variations of the mean backscatter strength calculated along the axis. Lower densities of seamounts and thicker sediments are producing lower and heterogeneous reflectivity levels in the deepest part of the axial valley floor between 61°45′E and 63°45′E. We propose that cooler mantle temperatures inducing construction of fewer volcanoes occur beneath this part of the ridge. The mean backscatter strength along the SWIR axis decreases dramatically toward the Rodrigues Triple Junction suggesting that volcanic production is reduced between 68°20′E and 69°20′E and that the transition from amagmatic tectonic deformation at the triple junction to new seafloor spreading occurs between 69°20′E and 70°E. 相似文献
13.
Francis Freire Richard Gyllencreutz Rooh Ullah Jafri Martin Jakobsson 《Geo-Marine Letters》2014,34(4):315-325
The western Svalbard continental margin contains thick sediment sequences with areas known to contain gas hydrates. Together with a dynamic tectonic environment, this makes the region prone to submarine slides. This paper presents results from geophysical mapping of the deepest part of the high Arctic environment, the Molloy Hole. The mapping includes multibeam bathymetry, acoustic backscatter and sub-bottom profiling. The geophysical data reveal seabed features indicative of sediment transport and larger-scale mass wasting. The large slide scar is here referred to as the Molloy Slide. It is located adjacent to the prominent Molloy Hole and Ridge system. The slide is estimated to have transported >65 km3 of sediments over the deep axial valley of the Molloy Ridge, and further into the Molloy Hole. A unique feature of this slide is that, although its run-out distance is relatively short (<5 km), it extends over an enormous vertical depth (>2,000 m) as a result of its position in a complex bathymetric setting. The slide was most likely triggered by seismic activity caused by seafloor spreading processes along the adjacent Molloy Ridge. However, gas-hydrate destabilization may also have played a role in the ensuing slide event. 相似文献
14.
J. A. Karson P. J. Fox H. Sloan K. T. Crane W. S. F. Kidd E. Bonatti J. B. Stroup D. J. Fornari D. Elthon P. Hamlyn J. F. Casey D. G. Gallo D. Needham R. Sartori OTTER 《Marine Geophysical Researches》1984,6(2):109-141
Seven dives in the submersible ALVIN and four deep-towed (ANGUS) camera lowerings have been made at the eastern ridge-transform intersection of the Oceanographer Transform with the axis of the Mid-Atlantic Ridge. These data constrain our understanding of the processes that create and shape the distinctive morphology that is characteristic of slowly-slipping ridge-transform-ridge plate boundaries. Although the geological relationships observed in the rift valley floor in the study area are similar to those reported for the FAMOUS area, we observe a distinct change in the character of the rift valley floor with increasing proximity to the transform. Over a distance of approximately ten kilometers the volcanic constructional terrain becomes increasingly more disrupted by faulting and degraded by mass wasting. Moreover, proximal to the transform boundary, faults with orientations oblique to the trend of the rift valley are recognized. The morphology of the eastern rift valley wall is characterized by inward-facing scarps that are ridge-axis parallel, but the western rift valley wall, adjacent to the active transform zone, is characterized by a complex fault pattern defined by faults exhibiting a wide range of orientations. However, even for transform parallel faults no evidence for strike-slip displacement is observed throughout the study area and evidence for normal (dip-slip) displacement is ubiquitous. Basalts, semi-consolidated sediments (chalks, debris slide deposits) and serpentinized ultramafic rocks are recovered from localities within or proximal to the rift valley. The axis of accretion-principal transform displacement zone intersection is not clearly established, but appears to be located along the E-W trending, southern flank of the deep nodal basin that defines the intersection of the transform valley with the rift floor. 相似文献
15.
Bo Liu Sanzhong Li Suhua Jiang Yanhui Suo Lingli Guo Yongming Wang Huixuan Zhang 《Marine Geophysical Researches》2017,38(1-2):137-147
Transform faults in back-arc basins are the key to revealing the opening and development of marginal seas. The Okinawa Trough (OT) represents an incipient and active back-arc or marginal sea basin oriented in a general NE-SW direction. To determine the strikes and spatial distribution of transform faults in the OT, this paper dissects the NW- and NNE-SN-trending fault patterns on the basis of seismic profiles, gravity anomalies and region geological data. There are three main NW-trending transpressional faults in the OT, which are the seaward propagation of NW-trending faults in the East China Continent. The NNE-SN-trending faults with right-stepping distribution behave as right-lateral shearing. The strike-slip pull-apart process or transtensional faulting triggered the back-arc rifting or extension, and these faults evolved into transform faults with the emergence of oceanic crust. Thus, the transform fault patterns are inherited from pre-existing oblique transtensional faults at the offsets between rifting segments. Therefore, the OT performs the oblique spreading mechanism similar to nascent oceans such as the Red Sea and Gulf of Aden. 相似文献
16.
Petrological-geochemical data were obtained for intrusive rocks (gabbroids) recovered on the eastern flank of the Knipovich Ridge by deep-sea site 344 (DSDP, Leg 238). It was found that these rocks are similar to basalts and basaltic glasses studied in the adjacent sections of the ridge rift zone [7, 8]. This indicates that the intrusive rocks and erupted lavas are comagmatic. The gabbroids, basalts, and their quenched glasses were derived by differentiation in different-depth chambers and feeder channels. The petrochemical features of the gabbros and basalts (low Fe content, oxidized magnetic minerals) caused their weak magnetic properties. Owing to the multidirectional movements of the oceanic blocks, the bodies of the intrusive and effusive rocks their lost strict linearity and produced the mosaic anomalous magnetic field of the Knipovich Ridge. 相似文献
17.
The North Gabon coastal rift basins consist of a set of 130–150 long-segment asymmetrically tilted half grabens (Interior Basin) and 000–020 short-segment en échelon half grabens (N'Komi Basin) separated by 040–060 major transverse faults. Tectono-sedimentary analysis of field and subsurface data reveals the control exerted by extensional tectonism over continental sedimentation. During Berriasian to early Barremian times, uniform uniaxial 040–060 extension was responsible for the stretching of the brittle upper crust over a 100-km wide domain. During late Barremian–early Aptian times, the main locus of extension stepped westward resulting in severe end-rift uplift and erosion of the failed Interior and N'Komi rift basins. Early Cretaceous coastal rifts in North Gabon display a wide range of styles from oblique rifting (N'Komi Basin), normal rifting (Interior Basin) to transform rifting. The pre-existing Precambrian tectonic fabric exerts a strong control over the mode and over the 100–300 km-scale segmentation of the rifting. 相似文献
18.
GLORIA imagery of the Lau Basin north of 17°S shows several morphotectonic terrains: a basement ridge and sedimented inter-ridge area in the SE; a nascent triple junction in the NE; a deeply sedimented basinal terrain in the central area; a linear neovolcanic zone striking NNESSW in the NW; and the northern flank of a leaky transform, the Peggy Ridge. Extension is now being accommodated at two main areas of spreading, but as no site of persistent long-term backarc crustal accretion is evident in this 250-km-wide portion of the basin, we conclude that past extension was largely by formation of pull-apart basins and local magmatism. 相似文献
19.
塔斯曼海位于西南太平洋地区，处于印度-澳大利亚板块和西兰板块之间，大地构造背景复杂。该地区是全球油气资源勘探的重点海域之一，但是国内对该地区的研究相当匮乏。本文根据塔斯曼海海域的自由空气重力异常对塔斯曼海海域的构造单元进行了划分，前人关于塔斯曼海的研究主要集中在Resolution海岭北部，我们认为塔斯曼海的范围应包括Resolution海岭以南，麦夸里海岭以西，塔斯曼断裂带以东的区域（即南部次盆）。结果显示，塔斯曼海域及邻区包括3个一级构造单元:东澳大利亚陆缘、西兰板块和塔斯曼海盆，且塔斯曼海盆可进一步划分为西部次盆、东部次盆和南部次盆。本文基于塔斯曼海域90 Ma以来的洋壳年龄数据编制了构造演化图，将塔斯曼海的形成演化过程分为4个阶段:（1）中生代陆内裂谷期（90~83 Ma BP）；（2）塔斯曼海扩张阶段（83~61 Ma BP）；（3）塔斯曼海北部扩张停止阶段（61~52 Ma BP）；（4）塔斯曼海南部改造阶段（52 Ma BP至今）。 相似文献
20.
郯庐断裂带自南而北穿越渤海东部,自中生代中期至新生代中期表现裂谷发育特征。裂谷发育经历两个旋回,各旋回的裂谷发育演化、盆地分布格局,沉积相带,沉积补偿速度等均受断裂带的断裂活动的强烈控制。 相似文献