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1.
K.M. Storetvedt C.M. Carmichael A. Hayatsu H.C. Palmer 《Physics of the Earth and Planetary Interiors》1978,16(4):379-392
The Duncansby volcanic neck, intruding the Middle Devonian red beds of north Caithness, Scotland, has revealed two significantly different axes of magnetization, yielding pole positions at 149°E, 24°N and 126.5°E, 60°N, respectively. The first pole, which is interpreted as corresponding to the oldest magnetization, is in perfect agreement with Devonian polar estimates from west of the Great Glen Fault. It is tentatively suggested therefore that the Duncansby neck correlates with the Late Devonian volcanism in the nearby Orkney Islands though palaeomagnetism allows an upper age estimate of around Middle Carboniferous. The data support an earlier proposition of there being a palaeomagnetic discordance across the Great Glen Fault that can be interpreted in terms of a large-scale late- or post-Devonian transcurrent movement along this fracture zone. The original (? Late Devonian) magnetization has been nearly completely erased by the second phase of magnetization which, according to its pole position, most likely dates from about the Middle Jurassic. The latter magnetization is thought to be a consequence of burial, the coastal districts of Caithness having participated in the general subsidence of the North Sea area in late Palaeozoic and Mesozoic times. The burial magnetization, involving VPTRM and or TCRM processes, is considered to have been “frozen-in” as a result of uplift in connection with the well-documented mid-Jurassic tectonic phase that affected the northern North Sea basin, including the adjacent Moray Firth area. K/Ar analyses of the Duncansby intrusion give apparent ages ranging from 258 to 239 Ma. These dates, which lie between the two geological events inferred from palaeomagnetism, are not seen as true rock ages but rather as the result of a partial Ar loss during burial reheating. 相似文献
2.
The Middle to Late Cambrian loop in the North American apparent polar wander path (APWP) has been variously attributed to tectonic rotations, remagnetizations and primary magnetizations. Although no primary thermal remanent magnetizations or primary detrital remanent magnetizations have as yet been demonstrated, the temporally self-consistent nature of the loop has been used as an argument for primary magnetizations. We have studied535 ± 5Ma nepheline syenites and syenites of the McClure Mountain alkalic complex, as well as495 ± 10Ma red trachyte dikes which intruded the complex, in an effort to find a primary TRM. Because Zijderveld analysis yielded consistent results for only one trachyte dike, remagnetization great-circle analysis was employed, giving a pole for the trachyte dikes at the tip of the loop (43°N, 114°E), while the syenites and nepheline synenites gave a pole at the base of the loop (18°N, 142°E). The magnetic carrier in the trachytes is hematite which apparently formed during a pervasive hydrothermal alteration. KAr whole rock dating of the trachytes suggests a Pennsylvanian age for the alteration, and thus a late Paleozoic remagnetization of the trachytes. Thus, the low-latitude Cambrian pole is confirmed, but we find no evidence in this study to support the primary nature of the Cambrian APWP. 相似文献
3.
Hans Wensink 《Earth and Planetary Science Letters》1983,63(2):325-334
Paleomagnetic results are reported from 13 sites of red beds of Early Devonian age from Central Iran. Detailed paleomagnetic analyses were carried out. Two types of partial progressive demagnetization were applied, one using alternating magnetic fields, the other heating. These procedures resulted in the detection of the characteristic remanences with a mean direction with D = 24.2°, I = 1.3° (α95 = 10.1°). The paleomagnetic pole is located at 51.3°N, 163.7°W. If one shifts the Iranian landmass to its most likely position in the Gondwana configuration, then the position of the paleomagnetic pole coincides with the alternative polar wander path [14,15] which crossed South America in early Middle Paleozoic times. 相似文献
4.
Late Paleozoic brachiopod faunas of the South Kitakami Belt, northeast Japan, and their paleobiogeographic and tectonic implications 总被引：2，自引：0，他引：2
Abstract Late Paleozoic (Middle Devonian, Early Carboniferous and Middle Permian) brachiopod faunas of the South Kitakami Belt, northeast Japan, are closely related paleobiogeographically to those of the Xinjiang–Inner Mongolia–Jilin region, northwest–northeast China. This relationship suggests that the South Kitakami Belt was part of the trench or continental shelf bordering the northern and eastern margins of North China (Sino-Korea) during the Middle Devonian to Middle Permian times. Among the three models on the origin and tectonic development of the South Kitakami Belt, the strike–slip model is most consistent, but both the microcontinent model and the nappe model have considerable inconsistencies with the above paleobiogeographic and paleogeographic evidence. 相似文献
5.
J.D.A. Piper 《Earth and Planetary Science Letters》1979,44(2):176-192
Palaeomagnetic results from the Lower Palaeozoic inliers of northern England cover the upper part of the (Middle Ordovician) Borrowdale Volcanic Series (palaeomagnetic pole 208°E, 18°S, A95 = 9.4°), minor extrusive units relating to the Caradoc and Ashgill stages of Ordovician times, intrusive episodes of Middle Ordovician and Middle Silurian to Late Devonian age, and the Shap Granite of Devonian (393 m.y.) age (palaeomagnetic pole 313°E, 33°S, A95 = 5.6°).A complete assessment of Ordovician to Devonian palaeomagnetic data for the British region shows that the pole was nearly static relative to this region for long intervals which were separated by shifts occupying no more than a few millions of years. The mean palaeomagnetic poles are: Ordovician (6°E, 16°S), Lower Silurian (58°E, 16°N), Middle Silurian/Lower Devonian (318°E, 6°N) and Middle/Upper Devonian (338°E, 26°S); the first two shifts separating these mean poles can be explained predominantly in terms of rotational movements of the crustal plate but the last involved appreciable movement in palaeolatitude.Comparison of Lower Palaeozoic palaeomagnetic data from the British region with contemporaneous data from continental Europe/North America on the Pangaean reconstruction reveals a systematic discrepancy in palaeolatitude between the two regions prior to Middle Devonian times. This discrepancy was eliminated during a few millions of years of Lower/Middle Devonian times (ca. 395 m.y.) and can be explained in terms of ca. 3500 km of sinistral strike-slip movement close to the line of the orthotectonic Caledonides. This motion is linked both in time and place to the impingement of the Gondwanaland and Laurentian supercontinents during the Acadian orogeny; this appears to have displaced the British sub-plate until it became effectively locked between the Baltic and Laurentian regions. Although movement of the dipole field relative to the British region in Lower Palaeozoic times is now well defined, nearly one fifth of the total data show that the geomagnetic field was more complex than dipolar during this interval. Until the significance of these anomalies is fully resolved, the tectonic model derived from the palaeomagnetic data cannot be regarded as unambiguous. 相似文献
6.
In order to test two different proposals for the poorly defined African Paleozoic apparent polar wander path (APWP), a paleomagnetic study was carried out on Ordovician through Carboniferous clastic sediments from the Cape Fold belt, west of the 22nd meridian. One proposal involves a relatively simple APWP connecting the Ordovician Gondwana poles in North Africa with the Late Paleozoic poles to the east of South Africa in a more or less straight line crossing the present equator in the Devonian. The other proposal adds a loop to this path, connecting Ordovician poles in North Africa with poles to the southwest of South Africa and then returning to central Africa. This loop would occur mainly in Silurian time. New results reported herein yield paleopoles in northern and central Africa for Ordovician to lowermost Silurian and Lower to Middle Devonian formations. The best determined paleopole of our study is for the Early Ordovician Graafwater Formation and falls at 28°N, 14°E (k = 25, α95 = 8.8°, N = 28 samples). The other paleopoles are not based on sufficient numbers of samples, but can help to constrain the apparent polar wander path for Gondwana. Our results give only paleopoles well to the north of South Africa and we observe no directions within the proposed loop. Hence, if the loop is real, it must have been of relatively short duration (60–70 Ma) and be essentially of Silurian/Early Devonian age, implying very high drift velocities for Gondwana (with respect to the pole) during that interval. 相似文献
7.
Maureen B. Steiner 《Earth and Planetary Science Letters》1978,38(2):331-345
Three-quarters of the Summerville Formation and a small portion of the Curtis Formation of central Utah have been sampled at close stratigraphic spacing. The two formations constitute an intertonguing marine-marginal marine, tidal flat sequence representing middle Callovian time. The magnetic polarity sequence observed is dominantly reversed with a few relatively short normal intervals. The age of these formations corresponds to some portion of time within the Jurassic oceanic quiet zone. The fact that normal polarity was not prominent in these formations casts some doubt upon the hypothesis that a long period of normal polarity was the cause of the quiet zone. Furthermore, a literature compilation indicates that normal polarity did not dominate the Jurassic as had been thought. The pole position determined from the Middle Jurassic Summerville Formation slightly revises earlier results and suggests a tiny amount of apparent polar motion relative to North American between Late Triassic and Middle Jurassic time. 相似文献
8.
We report paleomagnetic results from oriented drill core samples collected at 10 sites (80 samples) from the Covey Hill and 19 sites (96 samples) from the overlying, fossiliferous Cha?teauguay Formations of the gently dipping Late Cambrian Potsdam Group sandstones exposed in the St. Lawrence Lowlands of Quebec. Stepwise thermal demagnetization analyses ave revealed the presence of two predominant groups of coherent magnetizations C-1 and C-2, after simple correction for bedding tilt. The C-1 group magnetization is a stable direction (D=332°, I=+18°) with unblocking temperatures (TUB) between 550 and 650°C, present in the older Covey Hill Formation; this direction is probably a chemical remanence acquired during the Covey Hill diagenesis and carried predominantly by hematite. The C-2 group magnetization (D=322°, I=+9°) is present at 13 sites of the younger Cha?teauguay Formation; this is probably carried by magnetite and represents a penecontemporaneous, depositional DRM, characterized by TUB spectra 400–550°C. We believe that C-2 is relatively younger than C-1 based on a combination of arguments such as the presence of opposite polarities, internal consistency, similarity and common occurrence of C-1 and C-2 respectively in the Covey Hill and Cha?teauguay members. The corresponding paleomagnetic poles C-1 (46°N, 149°E; dp, dm=3°, 5°) and C-2 (37°N, 156°E; dp, dm=2°, 5°) are not significantly different from most of the other Late Cambrian (Dresbachian-Franconian) poles derived from sediments exposed in the southern region (Texas) of the North American craton which are also believed to have been deposited during Croixian Sauk sea transgression similar to the Potsdam sandstones. Although adequate faunal control is lacking (in particular for the Covey Hill Formation), this comparison with the Cratonic poles suggests a Late Cambrian age to the Potsdam poles. The agreement between the results also gives the evidence for internal consistency of cratonic poles at least for Late Cambrian.The incoherent C-3 group remanence (D=250°, I=?15°) is commonly present at 7 sites in both the formations; this may not correspond to a reliable paleomagnetic signal. The other remanence C-4 (D=180°, I=+10°) is found only at 3 sites located in the uppermost stratigraphic levels of the Cha?teauguay Formation; the corresponding paleomagnetic pole (40°N, 107°E) does not differ significantly from the Ordovician and some Late Cambrian poles. The present data are insufficient to resolve a problem in apparent polar wander for Middle and Late Cambrian time posed by the existence of high-latitude poles for some strata of Middle Cambrian age and low-latitude poles for some strata of Late Cambrian age. 相似文献
9.
Karl Zagora 《Studia Geophysica et Geodaetica》1995,39(3):298-301
Summary In the Rügen area of northern Germany, Old Red Sandstones, ranging from Late Emsian to Givetian in age, unconformably overlie deformed Ordovician strata. The Middle Devonian Old Red passes conformably up into a Late Devonian carbonate facies and then into the Lower Carboniferous, apparently without a break. 相似文献
10.
Duck K. Choi 《Island Arc》2019,28(1)
The Taebaeksan Basin is located in the mid‐eastern part of the southern Korean Peninsula and tectonically belonged to the Sino‐Korean Craton (SKC). It comprises largely the lower Paleozoic Joseon Supergroup and the upper Paleozoic Pyeongan Supergroup which are separated by a disconformity representing a 140 myr?long hiatus. This paper explores the early Paleozoic paleogeographical and tectonic evolution of the Taebaeksan Basin on the basis of updated stratigraphy, trilobite faunal assemblages, and detrital zircon U–Pb ages of the Joseon Supergroup. The Joseon Supergroup is a shallow marine siliciclastic‐carbonate succession ranging in age from the Cambrian Series 2 to Middle Ordovician. The Ongnyeobong Formation is the sole Upper Ordovician volcanic succession documented in the Taebaeksan Basin. It is suggested that in the early Paleozoic the Taebaeksan Basin was a part of an epeiric sea, the Joseon Sea, in east Gondwana. The Joseon Sea was the depositional site for lower Paleozoic successions of the SKC. Early Paleozoic sedimentation in the Joseon Sea commenced during the Cambrian Stage 3 (～ 520 Ma) and ceased by the end of the Darriwilian (～ 460 Ma). In the early Paleozoic, the SKC was located at the margin of east Gondwana and was separated from the South China Craton by an oceanic basin with incipient oceanic ridges, the Helan Trough. The spreading oceanic ridges and associated transform faults possibly promoted the uplift of the Joseon Sea, which resulted in cessation of sedimentation and break‐up of the SKC from core Gondwana by the end of the Ordovician. 相似文献
11.
Bin Zhang Wen Chen JingBo Sun Shun Yu JiYuan Yin Jie Li Yan Zhang XinYu Liu Li Yang Xia Yuan 《中国科学:地球科学(英文版)》2016,59(2):349-361
The uplift and exhumation process in the Tianshan orogen since the late Paleozoic were likely related to the preservation of ore deposits. This study involved reconstructing the whole tectonic thermal history of the Ouxidaban pluton in central South Tianshan Mountains based on hornblende/plagioclase Ar-Ar and zircon/apatite(U-Th)/He methods. The thermal history and uplift process of central South Tianshan Mountains since the late Paleozoic were analyzed according to the results of previous works and cooling/exhumation rate features. The hornblende yields a plateau age of 382.6±3.6 Ma, and the plagioclase yields a weighted mean age of 265.8±4.9 Ma. The Ouxidaban pluton yields weighted mean zircon(U-Th)/He age of 185.8±4.3 Ma and apatite(U-Th)/He age of 31.1±2.9 Ma, respectively. Five stages of tectonic thermal history of South Tianshan Mountains since the late Paleozoic could be discriminated by the cooling curve and modeling simulation:(1) from the latest Silurian to Late Devonian, the average cooling rate of the Ouxidaban pluton was 7.84°C/Ma;(2) from the Late Devonian to the latest Middle Permian, the average cooling rate was about 2.07°C/Ma;(3) from the latest Middle Permian to the middle Eocene, the cooling rate decreased to about 0.68°C/Ma, suggesting that the tectonic activity was gentle at this time;(4) a sudden increase of the cooling rate(5.00°C/Ma) and the exhumation rate(0.17 mm/a), and crustal exhumation of ~1.83 km indicated that the Ouxidaban pluton would suffer a rapid uplift event during the Eocene(~46?35 Ma);(5) since the middle Eocene, the rapid uplift was sustained, and the average cooling rate since then has been 1.14°C/Ma with an exhumation rate of about 0.04 mm/a and an exhumation thickness of 1.33 km. The strong uplift since the Cenozoic would be related to a far-field effect from the Indian and Eurasian plates' collision. However, it was hysteretic that the remote effect was observed in the Tianshan orogenic belt. 相似文献
12.
E. Salmon R. Montigny J.B. Edel A. Pique R. Thuizat M. Westphal 《Earth and Planetary Science Letters》1987,81(2-3)
The plutonic intrusion known as the Msissi norite (southern Morocco), which represents the single paleomagnetic reference pole for Africa in Devonian times, has been investigated. This Msissi intrusion is in fact an alkaline gabbro, a teschenite. K/Ar dating on separate biotites yields a 140 Ma age. Paleomagnetic results reveal a large scatter of isolated directions that precludes the computation of any Late Jurassic/Early Cretaceous paleopole. All these data lead us to reject this intrusion as a reference pole for the Devonian in Africa. The paleoposition of Africa in Devonian times remains, therefore, largely unknown. 相似文献
13.
新疆准噶尔二台地区晚古生代古极点位置与塔里木、哈萨克斯坦地块同时代极点位置无显著差别。实测古纬度更接近于用哈萨克斯坦极点计算得到的预期古纬度。因此,晚古生代准噶尔地块与哈萨克斯坦地块已是统一的整体。泥盆纪准噶尔地块内的准噶尔洋盆于晚石炭世闭合于乌伦古河一带。西伯利亚板块、塔里木、哈萨克斯坦地块等组成东部劳亚大陆的块体,尽管其运动演化有所差异,但都遵循了以西伯利亚板块为主体大致相同的总的运动演化过程,即晚古生代至中生代早期,由低纬度向高纬度的NW向运动和侏罗纪以来的SEE向运动 相似文献
14.
Evolution processes of Ordovician–Devonian arc system in the South‐Kitakami Massif and its relevance to the Ordovician ophiolite pulse 
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下载免费PDF全文 Kazuhito Ozawa Hirokazu Maekawa Ken Shibata Yoshihiro Asahara Masako Yoshikawa 《Island Arc》2015,24(2):73-118
The South Kitakami Massif is one of the oldest geological domains in Japan having Silurian strata with acidic pyroclastic rocks and Ordovician–Silurian granodiorite–tonalite basement, suggesting that it was matured enough to develop acidic volcanisms in the Silurian period. On the northern and western margin of the South Kitakami Massif, an Ordovician arc ophiolite (Hayachine–Miyamori Ophiolite) and high‐pressure and low‐temperature metamorphic rocks (Motai metamorphic rocks) exhumed sometime in the Ordovician–Devonian periods are distributed. Chronological, geological, and petrochemical studies on the Hayachine–Miyamori Ophiolite, Motai metamorphic rocks, and other early Paleozoic geological units of the South Kitakami Massif are reviewed for reconstruction of the South Kitakami arc system during Ordovician to Devonian times with supplementary new data. The reconstruction suggests a change in the convergence polarity from eastward‐ to westward‐dipping subduction sometime before the Late Devonian period. The Hayachine–Miyamori Ophiolite was developed above the eastward‐dipping subduction through three distinctive stages. Two separate stages of overriding plate extension inducing decompressional melting with minor involvement of slab‐derived fluid occurred before and after a stage of melting under strong influence of slab‐derived fluids. The first overriding plate extension took place in the back‐arc side forming a back‐arc basin. The second one took place immediately before the ophiolite exhumation and near the fore‐arc region. We postulate that the second decompressional melting was triggered by slab breakoff, which was preceded by slab rollback inducing trench‐parallel wedge mantle flow and non‐steady fluid and heat transport leaving exceptionally hydrous residual mantle. The formation history of the Hayachine–Miyamori Ophiolite implies that weaker plate coupling may provide preferential conditions for exhumation of very hydrous mantle. Very hydrous peridotites involved in arc magmatism have not yet been discovered except for in the Cambrian–Ordovician periods, suggesting its implications for global geodynamics, such as the thermal state and water circulation in the mantle. 相似文献
15.
用热退磁辅以交变退磁方法对采自塔里木盆地阿克苏地区四石厂剖面47个采样点518块标本进行了逐步磁清洗和测试。由本征剩磁方向统计得到塔里木地台晚古生代的古地磁极位置(晚泥盆世φ=10.5°S、λ=151.2°E;晚石炭世φ=52.2°N、λ=179.5°E;早二叠世φ=56.5°N,λ=190.1°E)。古地磁结果表明:塔里木地台在晚古生代是北方大陆的块体之一。从晚石炭世至早二叠世塔里木地台已和北方的哈萨克斯坦板块、西伯利亚地台、俄罗斯地台等连成一片,并且从中生代以来它们之间的相对位置没有发生过大规模的变动 相似文献
16.
Sea-level changes and hydrothermal sedimentary mineralization of large-superlarge ore deposits among Sinian to Triassic in South China 总被引：2，自引：0，他引：2
Among the Sinian to Triassic strata in South China, the stratiform, quasi-stratiform and lenticular metallic deposits in association with hydrothermal sedimentation mainly occur in the four periods: (1) the Sinian Datangpo interglacial period, (2) the early period of Early Cambrian, (3) the late period of Middle Devonian to early period of Late Devonian,and (4) the late period of Early Permian. The four mineralization periods all happened around the maximum flooding period in the third-order seal-level cycle during the ascending stage in the first-order sea-level cycle. The deep seawater layer, starved and non-compensatory basin, low sedimentary rate, and low energy and anoxic environment during the maximum flooding period are very suitable for the formation and preservation of large to superlarge hydrothermal sedimentary deposits. The maximum flooding period also coincided with the intensified regional tectonism, extensive deep magmatism and hydrothermal sedimentation, which provide, for the formation of large to superlarge hydrothermal sedimentary deposits through the rapid accumulation of hydrothermal sediments, the needed dynamics, ore-forming materials and favorable passway for hydrothermal fluids to enter the basin. 相似文献
17.
Among the Sinian to Triassic strata in South China, the stratiform, quasi-stratiform and lenticular metallic deposits in association with hydrothermal sedimentation mainly occur in the four periods: (1) the Sinian Datangpo interglacial period, (2) the early period of Early Cambrian, (3) the late period of Middle Devonian to early period of Late Devonian, and (4) the late period of Early Permian. The four mineralization periods all happened around the maximum flooding period in the third-order seal-level cycle during the ascending stage in the first-order sea-level cycle. The deep seawater layer, starved and non-compensatory basin, low sedimentary rate, and low energy and anoxic environment during the maximum flooding period are very suitable for the formation and preservation of large to superlarge hydrothermal sedimentary deposits. The maximum flooding period also coincided with the intensified regional tectonism, extensive deep magmatism and hydrothermal sedimentation, which provide, for the formation of large to superlarge hydrothermal sedimentary deposits through the rapid accumulation of hydrothermal sediments, the needed dynamics, ore-forming materials and favorable passway for hydrothermal fluids to enter the basin. 相似文献
18.
Palaeomagnetism of the Msissi norite (Morocco) and the Palaeozoic reconstruction of Gondwanaland 总被引：1，自引：0，他引：1
E.A. Hailwood 《Earth and Planetary Science Letters》1974,23(3):376-386
Palaeomagnetic results are reported from eight sites in an Upper Devonian basic intrusion (the Msissi norite) in southeast Morocco. Specimens from one site are suspected of having been affected by lightning, but results from the other seven sites indicate the presence of a less-stable component, probably of viscous origin. The pole position corresponding to the stable component(0.5°S, 25°E, A95 = 16.5) is interposed between the Middle Cambrian/Ordovician pole and the Lower Carboniferous pole on the African polar wander curve. When the southern continents are reassembled on the Smith/Hallam reconstruction of Gondwanaland the new Moroccan Devoniån pole is in excellent agreement with the corresponding portion of the main Australian polar-wander curve. This places additional constraints on the possible date of fusion of the separate Southeast Australian plate with the rest of Gondwanaland, postulated recently on palaeomagnetic grounds by M.W. McElhinny and B.J.J. Embleton (1974). The combined African/Australian polar-wander curve is compared with the South American curve, and two possible interpretations of available data are discussed, one involving possible relative tectonic motion between South America and the rest of Gondwanaland during the Lower and Middle Palaeozoic, and the other, favoured here, requiring a reassessment of the ages of several South American pole determinations. 相似文献
19.
20.
LiangShu Shu Yan Wang JinGeng Sha ShaoYong Jiang JinHai Yu YanBin Wang 《中国科学D辑(英文版)》2009,52(12):1969-1978
Two types of the Jurassic basins are distinguished in SE China based on their geodynamic features: the Late Triassic-Early
Jurassic post-orogenic basins and the Middle Jurassic intra-continental extensional basins. The Lower Jurassic sequence shows
a change from coarse- to fine-grained accumulation, suggesting a gradually deepening depositional environment from river to
shore-lake and to deep-water lake. In contrast, the Middle Jurassic accumulation was changed from claystone to conglomerate
along the coastal provinces in SE China, indicative of an initial crustal uplift. The Wuyi Mountains have been a paleogeograghic
separating zone since the Middle Jurassic. The Late Jurassic strata are absent in most areas of SE China. A large-scale bimodal
intra-continental rift-type volcanism occurred during the Middle Jurassic along a 40–60 km wide and 200 km long area in western
Fujian and southern Jiangxi provinces, which is most likely the strongest volcanism in SE China since the Cambrian. The SHRIMP
zircon U-Pb analyses on the rhyolite from the Dongkeng basin in the southern Jiangxi area yield a concord U-Pb age of 160±0.5
Ma, providing an upper age limit for the bimodal volcanic eruption. The analyses of the basin features indicate a change of
the depositional environment during the interval from Middle Triassic to Late Triassic from a shallow-sea to an intra-continent
in SE China in response to the strong collision between the Yangtze and North China Blocks. Sedimentary structures record
a southward direction of Early Jurassic paleo-currents, reflecting that their source areas were to the north side. We propose
that the Wuyi region was uplifted as early as Middle Jurassic, followed by a wide E-W-trending extended depression and bimodal
volcanism in the western foot of the Wuyi Mountains. Presumably the uplift of the Wuyi domain changed the Middle Jurassic
paleogeographic outline and formed the transformational tectonic regime from compression to extension as a tectonic response
to the Pacific plate subduction. 相似文献