阿尔金断裂晚新生代左旋走滑位错的地质新证据

通过对沿阿尔金断裂中段 (位于东经 88°至 92°)发育的晚第三纪走滑盆地沉积历史和走滑变形过程的野外观测以及对第四纪索尔库里盆地形成和演化过程的沉积环境复原的分析 ,提出了阿尔金断裂中段晚新生代左旋走滑位错的地质新证据。研究表明 ,晚第三纪走滑盆地经历了中新世晚期至上新世早期斜张走滑拉分和上新世晚期以来左旋错动的演化过程 ,沉积体沿断裂的错位分布特征指示至少发生了 80 km的左旋走滑位错。发育于阿尔金山链内部的索尔库里盆地起源于晚第三纪早期强烈的侵蚀作用 ,成为柴达木盆地快速沉积的主要物源区。该侵蚀盆地于中晚更新世闭合并演化成一个独立的沉积盆地。通过侵蚀盆地外流通道的复原指示阿尔金断裂自晚第三纪以来累积了 80～ 1 0 0 km的左旋位错。在此基础上 ,结合穿越断裂构造的 级区域水系形成的洪积裙宽度和主干河道沿断裂迹线的拐折长度 ,探讨了阿尔金断裂晚新生代左旋走滑位错量沿走向分布的特征 ,估算了左旋走滑速率     

Latest Miocene and Pleistocene ages of faulting, determined by 40Ar/39Ar single-crystal dating of airfall tuff and silicic extrusives of the Erciyes Basin, central Turkey: evidence for intraplate deformation related to the tectonic escape of Anatolia

The Ericiyes Basin is a trans‐tensional basin situated 20 km north of the regional Ecemi? Fault Zone. Recently it has been hypothesized that faulting within the Erciyes Basin links with the Ecemi? Fault Zone further south as part of a regional Central Anatolian Fault Zone. New ⁴⁰Ar/³⁹Ar dating of volcanic and volcaniclastic rocks adjacent to faults, both along the margins and in the centre of the Erciyes Basin, constrains the timing of basin inception and later faulting. Extensional faulting occurred along the eastern and western margins of the basin during the Early Messinian (latest Miocene). Sinistral and minor normal faulting were active along the axis of the basin during the early Pleistocene. These fault timings are similar to those inferred for the Ecemi? Fault Zone further south, and support the hypothesis that faulting within the Erciyes Basin and the Ecemi? Fault Zone are indeed linked.     

合肥盆地中新生代构造演化

综合地质、物探及钻井等资料,通过对合肥盆地的构造演化分析,认为合肥盆地是大别造山带和郯庐断裂带共同作用产生的中新生代残留盆地。受两大构造体系的共同作用,合肥盆地在印支期形成了盆地的基底,中新生代的演化大体可划分为以下5个时期：J1～J2坳陷盆地发育期;J3再生前陆盆地发育期;K1走滑盆地发育期;K2—E断陷盆地发育期;N—Q盆地消亡期。其中,在盆地发育早期受大别造山带影响较大,郯庐断裂作用较小;在盆地发育的中后期,郯庐断裂的影响逐渐成为主导因素。     

The role of thrust ramp reactivation in pull-apart mechanism of the Erzincan basin,North Anatolian Fault Zone,Turkey

The new field data obtained from the southwestern margin of the Erzincan pull-apart basin located on the eastern segment of North Anatolian Fault Zone indicate that the opening of the basin is not only controlled by pull-apart mechanism but also by a lateral ramp structure associated with SSE-NNW Late Miocene thrusting along the Sivas Basin. The fault bordering the southwestern margin of the basin is the lateral part of the Karada thrust that is the roof thrust of the Sivas fold-thrust system, rather than a segment of the North Anatolian Fault Zone. The Erzincan basin was nucleated as a lateral ramp basin during the Pliocene on the lateral ramp-related folds and expanded by the pull-apart opening mechanism between two segments of the North Anatolian Fault Zone. The WSW-ENE pull-apart opening of the basin was recorded by the Pliocene lacustrine-fluvial sediments and Quaternary volcanics as listric normal faulting.     

Miocene formations and NE-trending right-lateral strike–slip tectonism in Thrace,northwest Turkey: geodynamic implications

In the Thrace Peninsula, Neogene units were deposited in two areas, the Enez Basin in the south and the Thrace Basin in the north. In the southwesternmost part of the peninsula, upper lower–lower upper Miocene continental to shallow marine clastics of the Enez Formation formed under the influence of the Aegean extensional regime. During the last stage of the transpressional activity of the NW-trending right-lateral strike–slip Balkan–Thrace Fault, which had controlled the initial early middle Eocene deposition in the Thrace Basin, a mountainous region extending from Bulgaria eastwards to the northern Thrace Peninsula of Turkey developed. A river system carried erosional clasts of the metamorphic basement southwards into the limnic depositional areas of the Thrace Basin during middle Miocene time. Deposition of fluvial, lacustrine, and terrestrial strata of the Ergene Formation, which conformably and transitionally overlie the Enez Formation, began in the late middle Miocene in the southwest part and in the late Miocene in the north‐northeast part of the basin. Activity along the NE-trending right-lateral strike–slip faults (the Xanthi–Thrace Fault Zone) extending from northeast Greece northeastwards through the Thrace Peninsula of Turkey to the southern shelf of the western Black Sea Basin began during the middle Miocene in the northern Aegean, at the beginning of the late Miocene in the southwest part, and at the end of the late Miocene in the northeast part of the Thrace region. Although the Neogene deposits in the Thrace Basin were evaluated as the products of a northerly fault, our data indicate that the NW-trending northerly fault zone became effective only during the initial stage of the basin development. The later stage deposition in the basin was controlled by the NE-trending Xanthi–Thrace Fault Zone, and the deposits of this basin progressively evolved north/northeastwards during the late Miocene. During the late early Miocene–late Miocene interval, extension within the Thrace region was part of the more regional Aegean extensional realm, but from latest Miocene time, it has been largely decoupled from the Aegean extensional realm to the south.     

Evolution of the Taupo-Hikurangi subduction system

The present day Taupo-Hikurangi subduction system is a southward extension of the Tonga-Kermadec Arc system into a sediment-rich continental margin environment. It consists of a shallow structural trench (the Hikurangi Trough), a 150 km wide, imbricate thrust controlled accretionary borderland (the continental slope, shelf, and coastal hills of eastern North Island), a frontal ridge (the main “greywacke” ranges of North Island), and a volcanic arc and marginal basin (the Taupo Volcanic Zone).Structural elements become progressively more elevated and subduction more oblique towards the south. The whole NNE-trending system is truncated at a largely strike-slip, transform boundary that extends along the southwestern part of the Hikurangi Trough and the Hope fault of South Island to the main Alpine Fault.The volcanic arc is 200–270 km from the structural trench and comprises a NNE trending chain of andesite-dacite volcanoes extending along the eastern side of the Taupo Volcanic Zone. Most of the andesites are olivine-bearing and have been erupted within the last 50,000 years.It is suggested the Taupo-Hikurangi margin has evolved by rotation of accretionary elements, from an original NW-trending subduction system north of New Zealand. The older elements of the prism were associated with subduction of a re-entrant of the Pacific Plate (and perhaps the South Fiji Basin) in Mid Tertiary times. They subsequently became separated from their NW-trending volcanic arc by dextral strike-slip movement along curved faults east of the main “greywacke” ranges. During the Plio-Pleistocene, oblique subduction and accretion intensified as the Taupo-Hikurangi margin rotated into line with the NNE-trending Kermadec system and a marginal basin was developed along a similar trend to form the Taupo Volcanic Zone. Within the last 50,000 years olivine-bearing andesite volcanism has commenced along the eastern side of the Taupo Volcanic Zone.     

Tectonic segmentation of the Burmese-Indonesian arc

Several lines of evidences, which include change in trend and offset in arcs, bathymetry and sedimentation, faulting in the region, change in composition and trend of the line of volcanoes, spatial distribution of earthquakes and change in dip of the Benioff zone, suggest a tectonic segmentation of the Burmese-Indonesian Arc. Two transverse boundary zones, viz., the North Andaman Boundary Zone and the Sunda Boundary Zone separating segments of the arc are identified. Larger than usual thickness of the oceanic crust beneath the Ninetyeast Ridge reduces the average density of the lithosphere carrying the ridge. The buoyancy effect caused by the reduced average density inhibits the subduction of an approximately triangular shaped lithosphere between the Burmese-Indonesian Arc and the Ninetyeast Ridge, which in turn causes tectonic segmentation along the arc. The model predicts and some available focal mechanism solutions confirm left lateral northeast faulting within the Sunda Boundary Zone.     

Palaeostress analysis of the northern Nijar and southern Vera basins: constraints for the Neogene displacement history of major strike-slip faults in the Betic Cordilleras, SE Spain

This paper presents the results of a detailed structural analysis of the northern Nijar and southern Vera basins with special emphasis on the evolution of the regional stress field and the associated timing of movement of the Serrata, Gafarillos and Palomares strike-slip fault zones. These major fault zones control the Neogene deformation of the SE Internal Betic Cordilleras in Spain. Detailed stress analysis on Neogene sediments of the Vera and Nijar basins shows a strike-slip regime with NW–SE-oriented subhorizontal maximum principal stress (σ₁) during Tortonian and earliest Messinian times. Under the influence of this stress field, dextral displacement along the N090E-trending Gafarillos fault zone resulted in deformation of the sediments of the southern Sorbas and northeastern Nijar basins. During the early Messinian a clock-wise rotation of the stress field occurred. Stress analysis in rocks with late–early Messinian up to Quaternary ages in the Nijar and Vera basins indicates a strike-slip regime with N–S-oriented subhorizontal maximum principal stress (σ₁). Under the influence of this stress field the main activity along the N010E-striking Palomares strike-slip fault zone took place, resulting in deformation of the Neogene sediments of the southeastern Vera basin and culminating in a maximum sinistral displacement of more than 20 km. At the same time the stress field was not suitably oriented to exert a large shear component on the Gafarillos fault zone, which activity ended after the earliest Messinian. Fault and outcrop patterns of syntectonic Neogene sediments in the Vera basin show that displacement along the Palomares fault zone decreased at the end of the Middle Miocene although minor displacement phases may still have occurred during the Late Miocene and possibly even Pliocene. From the Middle Miocene onward, deformation in the Nijar basin was controlled by sinistral displacement along the N040E-trending Serrata strike-slip fault zone.     

A model of the Cenozoic evolution of northern New Zealand and adjacent areas of the southwest Pacific

New information from the southwest Pacific indicates that earlier attempts at formulating the evolution of the area assuming a single Upper Cenozoic magmatic arc are untenable. It now appears that there were two arcs during the Miocene and Pliocene, a western Northland/Three Kings Rise arc, and an eastern Tonga-Lau/Kermadec-Colville arc. Both appear to have developed above west-dipping subduction zones. It is suggested that the Norfolk- and Reinga basins formed as back-arc basins to the western arc, and that eastern North Island lay adjacent to Northland and formed the accretionary prism to that arc. Upper Cenozoic evolution of the region involved the simultaneous opening of the Norfolk/Reinga basins, consumption of the western portion of the Oligocene South Fiji Basin by subduction beneath the western arc, and eastwards movement of New Zealand/Three Kings Rise towards the Tonga/Kermadec arc. When the Kermadec and Hikurangi trenches came into line late in the Pliocene, the Tonga/Kermadec arc was able to propagate rapidly southwards into North Island; simultaneously the western arc became extinct, and the tectonic tempo and strike-slip faulting accelerated markedly throughout New Zealand. Eastern North Island was moved dextrally an uncertain distance relative to the western North Island, and rotated 25°–30° clockwise. This accounts for the paradox of a 22-m.y. old accretionary margin lying adjacent to a 2-m.y. old arc (Taupo Volcanic Zone) at the present day.     

胶莱盆地构造演化规律

胶莱盆地是中生代走滑拉分盆地，其形成与发育受到沂沭断裂和五莲—即墨—牟平断裂的控制。从晚侏罗世—晚白垩世经历了莱阳期、青山期和王氏期的盆地发展阶段。构造活动使不同时期的盆地格局发生改变，不同阶段盆地的次级构造单元也随之变化。不同阶段次级构造单元的形成与演变反映了构造活动对盆地发育的控制作用，表现在各单元之间沉积相发生突变。扬子板块与华北板块的碰撞，控制郯庐断裂带(沂沭断裂带)和五莲—即墨—牟平断裂的运动方向和强度，进而控制胶莱盆地的形成与发育。同时盆地发育也受到太平洋板块的影响与控制。     

马站盆地成因与晚白垩世郯庐断裂带的活动性

通过对郯庐断裂带内马站盆地中沉积岩相和同沉积构造分布特征的详细研究及盆地内凝灰岩夹层中的锆石裂变径迹年龄测定和盆内化石的研究,认为该盆地是一个形成于晚白垩世并与郯庐断裂带活动有关的走滑盆地。该盆地的形成表明郯庐断裂带,至少是其一部分,在晚白垩世时期仍存在明显的走滑活动。      

Detailed fault structure of the Tarutung Pull-Apart Basin in Sumatra,Indonesia, derived from local earthquake data

The Tarutung Basin is located at a right step-over in the northern central segment of the dextral strike-slip Sumatran Fault System (SFS). Details of the fault structure along the Tarutung Basin are derived from the relocations of seismicity as well as from focal mechanism and structural geology. The seismicity distribution derived by a 3D inversion for hypocenter relocation is clustered according to a fault-like seismicity distribution. The seismicity is relocated with a double-difference technique (HYPODD) involving the waveform cross-correlations. We used 46,904 and 3191 arrival differences obtained from catalogue data and cross-correlation analysis, respectively. Focal mechanisms of events were analyzed by applying a grid search method (HASH code). Although there is no significant shift of the hypocenters (10.8 m in average) and centroids (167 m in average), the application of the double difference relocation sharpens the earthquake distribution. The earthquake lineation reflects the fault system, the extensional duplex fault system, and the negative flower structure within the Tarutung Basin. The focal mechanisms of events at the edge of the basin are dominantly of strike-slip type representing the dextral strike-slip Sumatran Fault System. The almost north–south striking normal fault events along extensional zones beneath the basin correlate with the maximum principal stress direction which is the direction of the Indo-Australian plate motion. The extensional zones form an en-echelon pattern indicated by the presence of strike-slip faults striking NE–SW to NW–SE events. The detailed characteristics of the fault system derived from the seismological study are also corroborated by structural geology at the surface.     

康西瓦断裂带晚新生代构造地貌特征及其构造意义

文章详细调查了康西瓦断裂带发育的断层崖、断层陡坎、地震破裂带、错断山脊、拉分盆地、挤压脊、偏心洪积扇、错断水系等新构造运动形迹,这些新构造运动形迹表明了康西瓦断裂带在晚新生代以来发生了强烈的左旋走滑运动,并兼有正滑运动分量。数字地形高程模型(DEM)分析表明康西瓦断裂西端终止于塔什库尔干谷地东部的瓦恰河谷内,东端与著名的阿尔金断裂带相连。如果以喀拉喀什河和玉龙喀什河为参照系,康西瓦断裂晚新生代以来的左旋走滑累积位移量可达 80～85km,根据断裂带 8～12mm/a的长期走滑速率,推测康西瓦断裂带新生代以来的左旋走滑运动开始于约10Ma。结合我们获得的断裂带两侧岩浆岩的年龄,表明康西瓦断裂带左旋走滑运动的开始时代为晚中新世,现今康西瓦地区的构造地貌格局很可能是中新世晚期以来强烈的左旋走滑运动形成的。     

Devonian-Cretaceous repeated subsidence and uplift along the Teisseyre-Tornquist zone in SE Poland — Insight from seismic data interpretation

The Teisseyre-Tornquist Zone that separates the East European Craton from the Palaeozoic Platform forms one of the most fundamental lithospheric boundaries in Europe. Devonian to Cretaceous-Paleogene evolution of the SE segment of this zone was analyzed using high-quality seismic reflection data that provided detailed information regarding entire Palaeozoic and Mesozoic sedimentary cover, with particular focus on problems of Late Carboniferous and Late Cretaceous-Paleogene basin inversion and uplift. Two previously proposed models of development and inversion of the Devonian-Carboniferous Lublin Basin seem to only partly explain configuration of this sedimentary basin. A new model includes Late Devonian-Early Carboniferous reverse faulting within the cratonic area NE from the Kock fault zone, possibly first far-field effect of the Variscan orogeny. This was followed by Late Carboniferous inversion of the Lublin Basin. Inversion tectonics was associated with strike-slip movements along the Ursynów-Kazimierz fault zone, and thrusting along the Kock fault zone possibly triggered by deeper strike-slip movements. Late Carboniferous inversion-related deformations along the NE boundary of the Lublin Basin were associated with some degree of ductile (quasi-diapiric) deformation facilitated by thick series of Silurian shales. During Mesozoic extension and development of the Mid-Polish Trough major fault zones within the Lublin Basin remained mostly inactive, and subsidence centre moved to the SW, towards the Nowe Miasto-Zawichost fault zone and further to the SW into the present-day Holy Cross Mts. area. Late Cretaceous-Paleogene inversion of the Mid-Polish Trough and formation of the Mid-Polish Swell was associated with reactivation of inherited deeper fault zones, and included also some strike-slip faulting. The study area provides well-documented example of the foreland plate within which repeated basin inversion related to compressive/transpressive deformations was triggered by active orogenic processes at the plate margin (i.e. Variscan or Carpathian orogeny) and involved important strike-slip reactivation of crustal scale inherited fault zones belonging to the Teisseyre-Tornquist Zone.     

Using gemorphological markers to discriminate Neogene tectonic activity in the Precordillera of North Chilean forearc (24–25°S)

We study the Neogene tectonic activity in a sector of the Precordillera in the Andean forearc analysing aerial photographs, satellite images and fieldwork data. The interpretation of alluvial landforms, drainage organisation and evolution of intermittent river networks affecting post-Lower Miocene deposits allow us to recognize low intensity tectonic processes controlling the landscape evolution. All these geomorphological markers indicate no strike-slip offsets, but repeated and small tectonic pulses that reactivate previous structures originated under a transpressive context. The observed deformation pattern is the consequence of E–W orthogonal compression resulting in limited shortening, related to the accommodation of deformation in the Chilean forearc of the Neogene uplift of the Altiplano-Puna.     

琉球岛弧区弧前盆地新生代层序地层特征及沉积演化SCIEI北大核心CSCD

琉球弧前盆地位于菲律宾海板块北部与欧亚板块汇聚部位,发育于琉球海沟北部增生楔与琉球岛弧之间,是典型“沟-弧-盆”体系的组成单元。现利用多道地震资料,首次建立琉球弧前盆地的层序地层格架,分析其新生代层序地层特征,阐明弧前盆地沉积充填演化过程,并探讨各盆地主要物源。通过地震剖面解释分析,表明:①始新世为岛弧变质基底沉积期,晚渐新世晚期-早中新世阶段发育残余伸展盆地基底沉积,属于浅海环境,主要受岩浆活动影响,发育火山碎屑岩相;②中中新世-第四纪时期是弧前盆地的主体沉积期,盆地从半深海沉积环境向深海环境过渡,发育典型深海沉积相,局部为火山碎屑岩相;中中新世时北部的南琉球群岛是弧前盆地主要物源区;晚中新世至第四纪时期,台湾岛东北部陆区成为对该弧前盆地贡献最大的物源区,而南琉球群岛的物源供给量降为次要地位。该研究结果是对琉球岛弧及周缘构造控盆作用研究的拓展,并对台湾岛陆地与东部海域“源-汇”系统研究有重要的指导意义。     

Fault-block structure and state of stress in the Earth’s crust of the Gusinoozersky Basin and the adjacent territory,western Transbaikal region

The geological structure and tectonophysics of the Gusinoozersky Basin—a tectonotype of Mesozoic depressions in the western Transbaikal region—is discussed. New maps of the fault-block structure and state of stress in the Earth’s crust of the studied territory are presented. It is established that the Gusinoozersky Basin was formed in a transtensional regime with the leading role of extension oriented in the NW-SE direction. The transtensional conditions were caused by paths of regional tension stresses oriented obliquely to the axial line of the basin, which created a relatively small right-lateral strike-slip component of separation (in comparison with normal faulting) along the NE-trending master tectonic lines. The widespread shear stress tensors of the second order with respect to extension are related to inhomogeneities in the Earth’s crust, including those that are arising during displacement of blocks along normal faults. Folding at the basin-range boundary was brought about by gravity effects of normal faulting. The faults and blocks in the Gusinoozersky Basin remained active in the Neogene and Quaternary; however, it is suggested that their reactivation was a response to tectonic processes that occurred in the adjacent Baikal Rift Zone rather than to the effect of a local mantle source.     

A map-view restoration of the Alpine-Carpathian-Dinaridic system for the Early Miocene

A map-view palinspastic restoration of tectonic units in the Alps, Carpathians and Dinarides reveals the plate tectonic configuration before the onset of Miocene to recent deformations. Estimates of shortening and extension from the entire orogenic system allow for a semi-quantitative restoration of translations and rotations of tectonic units during the last 20 Ma. Our restoration yielded the following results: (1) The Balaton Fault and its eastern extension along the northern margin of the Mid-Hungarian Fault Zone align with the Periadriatic Fault, a geometry that allows for the eastward lateral extrusion of the Alpine-Carpathian-Pannonian (ALCAPA) Mega-Unit. The Mid-Hungarian Fault Zone accommodated simultaneous strike-perpendicular shortening and strike-slip movements, concomitant with strike-parallel extension. (2) The Mid-Hungarian Fault Zone is also the locus of a former plate boundary transforming opposed subduction polarities between Alps (including Western Carpathians) and Dinarides. (3) The ALCAPA Mega-Unit was affected by 290 km extension and fits into an area W of present-day Budapest in its restored position, while the Tisza-Dacia Mega-Unit was affected by up to 180 km extension during its emplacement into the Carpathian embayment. (4) The external Dinarides experienced Neogene shortening of over 200 km in the south, contemporaneous with dextral wrench movements in the internal Dinarides and the easterly adjacent Carpatho-Balkan orogen. (5) N–S convergence between the European and Adriatic plates amounts to some 200 km at a longitude of 14° E, in line with post-20 Ma subduction of Adriatic lithosphere underneath the Eastern Alps, corroborating the discussion of results based on high-resolution teleseismic tomography.The displacement of the Adriatic Plate indenter led to a change in subduction polarity along a transect through the easternmost Alps and to substantial Neogene shortening in the eastern Southern Alps and external Dinarides. While we confirm that slab-pull and rollback of oceanic lithosphere subducted beneath the Carpathians triggered back-arc extension in the Pannonian Basin and much of the concomitant folding and thrusting in the Carpathians, we propose that the rotational displacement of this indenter provided a second important driving force for the severe Neogene modifications of the Alpine-Carpathian-Dinaridic orogenic system.     

Tectonics and sedimentation in the Fohnsdorf-Seckau Basin (Miocene, Austria): from a pull-apart basin to a half-graben

The Miocene intramontane Fohnsdorf-Seckau Basin is situated at the junction of the sinistral Mur-Mürz-fault system and the dextral Pöls-Lavanttal fault system. The basin comprises a 2,400-m-thick coal-bearing fluviodeltaic-lacustrine succession (Lower to Middle Miocene, Upper Karpatian?/Lower Badenian) which is overlain by a 1,000-m-thick alluvio-deltaic conglomeratic succession (Apfelberg Formation, ?Middle/Upper Badenian) in the south. A three-stage model for the basin evolution has been reconstructed from structural analysis and basin fill geometries. During a first pull-apart phase, subsidence occurred along ENE-trending, sinistral strike-slip faults of the Mur-Mürz fault system and NE-SW to N-S-trending normal faults, forming a composite pull-apart basin between overstepping en-echelon strike-slip faults. The Seckau and Fohnsdorf sub-basins are considered as two adjacent pull-aparts which merged into one basin. During the second phase, N-S to NNW-SSE extension and normal faulting along the southern basin margin fault formed a half-graben, filled by wedge-shaped alluvial strata (Apfelberg Formation). During the third phase, after the end of basin sedimentation, the dextral Pöls-Lavanttal fault system reshaped the western basin margin into a positive flower structure.