Igneous series in island arcs: The northeastern Caribbean compared with worldwide island-arc assemblages

1980 ◽  
Vol 43 (2) ◽  
pp. 347-382 ◽  
Author(s):  
T. W. Donnelly ◽  
J. J. W. Rogers
Keyword(s):  
2009 ◽  
Vol 4 ◽  
pp. 273-288 ◽  
Author(s):  
S. D. Sokolov ◽  
G. Ye. Bondarenko ◽  
A. K. Khudoley ◽  
O. L. Morozov ◽  
M. V. Luchitskaya ◽  
...  

Abstract. A long tectonic zone composed of Upper Jurassic to Lower Cretaceous volcanic and sedimentary rocks is recognized along the Asian continent margin from the Mongol-Okhotsk fold and thrust belt on the south to the Chukotka Peninsula on the north. This belt represents the Uda-Murgal arc, which was developed along the convergent margin between Northeast Asia and Northwest Meso-Pacific. Several segments are identified in this arc based upon the volcanic and sedimentary rock assemblages, their respective compositions and basement structures. The southern and central parts of the Uda-Murgal arc were a continental margin belt with heterogeneous basement represented by metamorphic rocks of the Siberian craton, the Verkhoyansk terrigenous complex of Siberian passive margin and the Koni-Taigonos Late Paleozoic to Early Mesozoic island arc with accreted oceanic terranes. At the present day latitude of the Pekulney and Chukotka segments there was an ensimatic island arc with relicts of the South Anyui oceanic basin in a backarc basin. Accretionary prisms of the Uda-Murgal arc and accreted terranes contain fragments of Permian, Triassic to Jurassic and Jurassic to Cretaceous (Tithonian–Valanginian) oceanic crust and Jurassic ensimatic island arcs. Paleomagnetic and faunal data show significant displacement of these oceanic complexes and the terranes of the Taigonos Peninsula were originally parts of the Izanagi oceanic plate.


2004 ◽  
Vol 175 (5) ◽  
pp. 443-460 ◽  
Author(s):  
Rodolfo A. Tamayo* ◽  
René C. Maury* ◽  
Graciano P. Yumul ◽  
Mireille Polvé ◽  
Joseph Cotten ◽  
...  

Abstract The basement complexes of the Philippine archipelago include at least 20 ophiolites and ophiolitic complexes. These complexes are characterised by volcanic sequences displaying geochemical compositions similar to those observed in MORB, transitional MORB-island arc tholeiites and arc volcanic rocks originating from modern Pacific-type oceans, back-arc basins and island arcs. Ocean island basalt-like rocks are rarely encountered in the volcanic sequences. The gabbros from the ophiolites contain clinopyroxenes and plagioclases showing a wide range of XMg and An values, respectively. Some of these gabbros exhibit mineral chemistries suggesting their derivation from basaltic liquids formed from mantle sources that underwent either high degrees of partial melting or several partial melting episodes. Moreover, some of the gabbros display a crystallization sequence where orthopyroxene and clinopyroxene appeared before plagioclase. The major element compositions of coexisting orthopyroxenes and olivines from the mantle peridotites are consistent with low to high degrees of partial melting. Accessory spinels in these peridotites display a wide range of XCr values as well with some of them above the empirical upper limit of 0.6 often observed in most modern mid-oceanic ridge (MOR) mantle rocks. Co-existing olivines and spinels from the peridotites also exhibit compositions suggesting that they lastly equilibrated under oxidizing mantle conditions. The juxtaposition of volcanic rocks showing affinities with modern MOR and island arc environments suggests that most of the volcanic sequences in Philippine ophiolites formed in subduction-related geodynamic settings. Similarly, their associated gabbros and peridotites display mineralogical characteristics and mineral chemistries consistent with their derivation from modern supra-subduction zone-like environments. Alternatively, these rocks could have, in part, evolved in a supra-subduction zone even though they originated from a MOR-like setting. A simplified scenario regarding the early geodynamic evolution of the Philippines is proposed on the basis of the geochemical signatures of the ophiolites, their ages of formation and the ages and origins of the oceanic basins actually bounding the archipelago, including basins presumed to be now totally consumed. This scenario envisages the early development of the archipelago to be largely dominated by the opening and closing of oceanic basins. Fragments of these basins provided the substratum on top of which the Cretaceous to Recent volcanic arcs of the Philippines were emplaced.


1999 ◽  
Vol 36 (2) ◽  
pp. 209-225 ◽  
Author(s):  
Ralf O Maxeiner ◽  
Tom II Sibbald ◽  
William L Slimmon ◽  
Larry M Heaman ◽  
Brian R Watters

This paper describes the geology, geochemistry, and age of two amphibolite facies volcano-plutonic assemblages in the southern Hanson Lake Block and southeastern Glennie Domain of the Paleoproterozoic Trans-Hudson Orogen of east-central Saskatchewan. The Hanson Lake assemblage comprises a mixed suite of subaqueous to subaerial dacitic to rhyolitic (ca. 1875 Ma) and intercalated minor mafic volcanic rocks, overlain by greywackes. Similarly with modern oceanic island arcs, the Hanson Lake assemblage shows evolution from primitive arc tholeiites to evolved calc-alkaline arc rocks. It is intruded by younger subvolcanic alkaline porphyries (ca. 1861 Ma), synvolcanic granitic plutons (ca. 1873 Ma), and the younger Hanson Lake Pluton (ca. 1844 Ma). Rocks of the Northern Lights assemblage are stratigraphically equivalent to the lower portion of the Hanson Lake assemblage and comprise tholeiitic arc pillowed mafic flows and felsic to intermediate volcaniclastic rocks and greywackes, which can be traced as far west as Wapawekka Lake in the south-central part of the Glennie Domain. The Hanson Lake volcanic belt, comprising the Northern Lights and Hanson Lake assemblages, shows strong lithological, geochemical, and geochronological similarities to lithotectonic assemblages of the Flin Flon Domain (Amisk Collage), suggesting that all of these areas may have been part of a more or less continuous island arc complex, extending from Snow Lake to Flin Flon, across the Sturgeon-Weir shear zone into the Hanson Lake Block and across the Tabbernor fault zone into the Glennie Domain.


2021 ◽  
Author(s):  
Jarosław Majka ◽  
Karolina Kośmińska ◽  
Jakub Bazarnik ◽  
William C. McClelland

<p>We report on U-Pb zircon dating and bulk rock geochemistry results of intermediate to felsic rocks of the Thores Suite of the Pearya Terrane, northern Ellesmere Island (Arctic Canada).  Our new results together with the previously published data show that the Thores Suite was formed in the Early Ordovician (c. 490-470 Ma) as a part of an island arc. Some of the dated samples revealed common xenocrystic zircon. The latter yielded ages ranging between c. 2690 Ma and c. 520 Ma. The obtained ages of xenocrystic zircon are interpreted to be typical of Laurentia. We propose that the youngest obtained cluster of ages c. 580-570 Ma expresses a component typical for the Timanide Orogen, which is conventionally tied to Baltica. The newdataset sheds light on the history and understanding of the Thores Suite, which used to be explained as an effect of the M’Clintock orogenesis. The latter event was commonly presented as foreign to the major Caledonian orogenesis sensu stricto. In our view, the Thores Suite represents an island arc, which was formed on a fragment of continental crust dismembered during Iapetus opening. Importantly, the age of the Thores island arc is coeval with other island arcs and high pressure metamorphic units of the Scandinavian and Svalbard Caledonides. Thus, it is likely that the Thores volcanic island arc was a part of the larger arc system operating within northern Iapetus. The juxtaposition of the Thores arc with the other successions of the Pearya Terrane is ascribed to a major sinistral strike-slip escape fault-system developed along the northeastern margins of Baltica and Laurentia, broadly concurrent with the main Scandian collision between the two aforementioned continents. This crustal scale fault structure enabled the juxtaposition of numerous crustal blocks of different Precambrian ancestry that can be found in various regions of the current High Arctic, including Svalbard, Greenland and Ellesmere Island.</p><p>This research was supported by the National Science Centre (Poland) project no. 2015/17B/ST10/03114 and the internal AGH-UST funding to J. Majka, the internal grant of the Polish Geological Institute - NRI no. 62.9012.2014.00.0 to J. Bazarnik and the National Science Foundation (USA) grant EAR1650022 to J. Gilotti and W. McClelland.</p>


1973 ◽  
Vol 13 (1) ◽  
pp. 19
Author(s):  
Richard W. Murphy

Modern bathymetric, geophysical, and volcanic studies have revealed a remarkably consistent principal profile for island arcs of the Western Pacific. Examination of surface geology, however, suggests great diversity in the geological development of island arcs. Three island arc complexes show the diversity well: Japan, the Philippines, and the Northern Moluccas.Although Japan appears to have been an island arc in roughly its present configuration only since Early Miocene time, the surface geology indicates that Japan has formed part of the continental margin of Asia at least since Permian and probably Devonian time. Subduction polarity, as displayed in paired metamorphic belts; juxtaposition of continental rise prisms with contemporaneous oceanic suites; and overall tectonic fabric strongly supports belief in the existence of the Pacific Ocean since the Devonian. Hokkaido is a reversed island arc segment which together with Sakhalin is probably a relatively recent addition to the northeast Asian continental perimeter.The Philippines were formed by the Late Oligocene coalescence of at least four island arc-subduction zone complexes into a single archipelagic basin which has remained more or less coherent throughout Neogene time. Although the oldest Philippine fossils are Permian, the island arcs probably did not start to form until Late Cretaceous time. Neogene volcanism, intrusion and sedimentation are thought to be creating a new small continent out of materials that were originally entirely oceanic.Island arc systems flanking the Molucca Sea were born in Late Cretaceous time and now appear to be in a stage of coalescence similar to that of the Philippines in Late Oligocene time. The convergence of two west-dipping and one east-dipping Benioff zones, the existence of a very large negative isostatic gravity anomaly, the outcrop of fossil subduction zones and the existence of short topographic trench segments indicate an active, youthful region of crustal construction.


2021 ◽  
Author(s):  
Pengde Liu ◽  
Xijun Liu ◽  
Zhiguo Zhang ◽  
Yujia Song ◽  
Yao Xiao ◽  
...  

<p>    The subduction and closure of the Paleo-Asia Ocean generated the Central Asian Orogenic Belt (CAOB), which extends from the Urals in the west through Kazakhstan, northwestern China, Mongolia, and northeastern China to the Russian Far East. It is generally accepted that the CAOB comprises a complicated and varied collage of terranes, including island arcs, ophiolites, accretionary prisms, seamounts, and microcontinents. The CAOB is the world’s largest accretionary orogen and is also considered a type area for studying Phanerozoic continental growth. The accretionary processes of the orogen might have resulted from either the progressive duplication of a single and long-lived island-arc system or the collision of several island arcs and micro-continents, similar to the complex archipelago systems in the modern southwestern Pacific. West Junggar is located in a key area of the CAOB, has been a focus of studies of the tectonic evolution and crustal growth of the orogenic belt. West Junggar has been considered by some geologists as a paleo-Asian intra-oceanic subduction system, whereas others have variously argued that West Junggar was formed by single subduction, arc–arc collision, or ridge subduction, or by post-collisional processes after the early Carboniferous. An understanding of the Carboniferous tec-tonic setting is critical for determining the evolution of West Junggar. A series of early Carboniferous volcanic and intrusive rocks occur in the southern West Junggar. Our new zircon U–Pb geochronological data reveal that diorite intruded at 334.1 ± 1.1 Ma, and that basaltic andesite was erupted at 334.3 ± 3.7 Ma. These intrusive and volcanic rocks are calc-alkaline, display moderate MgO (1.62–4.18 wt.%) contents and Mg# values (40–59), low Cr (14.5–47.2 ppm) and Ni (7.5–34.6 ppm) contents, and are characterized by enrichment in light rare-earth elements and large-ion lithophile elements and depletion in heavy rare-earth elements and high-field-strength elements, meaning that they belong to typical subduction-zone island-arc magma. The rocks show low initial <sup>87</sup>Sr/<sup>86</sup>Sr ratios (0.703649 to 0.705008), positive Ɛ<sub>Nd(t) </sub>values (+4.8 to +6.2, mean +5.4), and young T<sub>DM</sub> Nd model ages ranging from 1016 to 616 Ma, indicating a magmatic origin from depleted mantle involving partial melting of 10%–25% garnet and spinel lherzolite. Combining our results with those of previous studies, we suggest that these rocks formed as a result of northwestward subduction of the Paleo-Asian Junggar oceanic plate, which caused partial melting of sub-arc mantle. We conclude that intra-oceanic arc magmatism was extensive in southern Paleo-Asian Ocean during the early Carboniferous.</p><p>This study was financially supported by the National Natural Science Foundation of China (41772059) and the CAS “Light of West China” Program (2018-XBYJRC-003).</p>


Geology ◽  
2007 ◽  
Vol 35 (8) ◽  
pp. 683 ◽  
Author(s):  
Carlos J. Garrido ◽  
Jean-Louis Bodinier ◽  
Bruno Dhuime ◽  
Delphine Bosch ◽  
Ingrid Chanefo ◽  
...  

Author(s):  
J. B. Whalen ◽  
K. L. Currie ◽  
O. van Breemen

ABSTRACTThe Topsails igneous terrane of western Newfoundland contains several intrusive and volcanic suites underlain and separated by screens of older intrusive rocks. The heterogeneous Hungry Mountain complex yielded U-Pb zircon upper and lower intercept ages of 2090 ± 75 Ma and 467 ± 8 Ma, demonstrating a significant inherited component of Aphebian age, while an adjacent suite of relatively massive granodioritic to granitic rocks yielded a slightly discordant U-Pb zircon age of 460 ± 10 Ma. The 438 ± 8 Ma age of the Rainy Lake complex, a suite of island arc type intrusive rocks, suggests it forms part of a Silurian magmatic episode, which also included Springdale Group bimodal volcanics (429 ± 4 Ma), and peralkaline granite and subvolcanic porphyries which intrude the Springdale Group (429 ± 3 Ma and 427 ±3 Ma, respectively). Most igneous units contain a slight component of inherited zircon, but initial 87Sr/86Sr ratios (average 0·704) are similar to calculated ‘Bulk Earth’ values at this time.Available data suggest that the Topsails terrane formed an oceanic tract with active volcanic island arcs when obduction commenced in early Ordovician time. The subsequent magmatic history, including the major but short-lived early Silurian magmatism, can be directly or indirectly related to obduction processes, including over-riding of the Topsails terrane by ophiolitic allochthons. There is no evidence of any Acadian (Devonian) igneous activity in the Topsails terrane.


The oceanic island arcs should represent the least complicated type of subduction related magmatism. Theoretically they represent an environment in which contamination by continental crustal materials does not occur. Basaltic lavas from most island arc systems have Sr, Nd and Pb isotope characteristics that do not deviate substantially from the normal arrays of mantle derived magmas. However, their distinctive trace element geochemistry requires a distinctive mantle source composition which is most readily achieved by metasomatism of the lherzolite of the mantle wedge by fluids ascending from the upper surface of the subducted slab. Such fluids may be variably enriched in 87 S r/ 86 Sr, in which case they will induce deviations from the Nd-Sr mantle array. In marked contrast, a range of basic to intermediate lavas from the Sunda-Banda arc of Indonesia and the Lesser Antilles island arc have a significant continental fingerprint to their isotopic compositions and show marked deviations from the Sr-Nd and Pb isotope mantle arrays. These data could be explained by the involvement of a terrigenous sedimentary component in the genesis of the slab derived fluids. However, they could equally reflect high level contamination of the ascending magmas by sediments in situ at the base of the island arc crust.


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