Structural and Morphologic Study of Shatsky Rise Oceanic
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Hikurangi Plateau: Crustal Structure, Rifted Formation, and Gondwana Subduction History
Article Geochemistry 3 Volume 9, Number 7 Geophysics 3 July 2008 Q07004, doi:10.1029/2007GC001855 GeosystemsG G ISSN: 1525-2027 AN ELECTRONIC JOURNAL OF THE EARTH SCIENCES Published by AGU and the Geochemical Society Click Here for Full Article Hikurangi Plateau: Crustal structure, rifted formation, and Gondwana subduction history Bryan Davy Institute of Geological and Nuclear Sciences, P.O. Box 30368, Lower Hutt, New Zealand ([email protected]) Kaj Hoernle IFM-GEOMAR, Wischhofstraße 1-3, D-24148 Kiel, Germany Reinhard Werner Tethys Geoconsulting GmbH, Wischhofstraße 1-3, D-24148 Kiel, Germany [1] Seismic reflection profiles across the Hikurangi Plateau Large Igneous Province and adjacent margins reveal the faulted volcanic basement and overlying Mesozoic-Cenozoic sedimentary units as well as the structure of the paleoconvergent Gondwana margin at the southern plateau limit. The Hikurangi Plateau crust can be traced 50–100 km southward beneath the Chatham Rise where subduction cessation timing and geometry are interpreted to be variable along the margin. A model fit of the Hikurangi Plateau back against the Manihiki Plateau aligns the Manihiki Scarp with the eastern margin of the Rekohu Embayment. Extensional and rotated block faults which formed during the breakup of the combined Manihiki- Hikurangi plateau are interpreted in seismic sections of the Hikurangi Plateau basement. Guyots and ridge- like seamounts which are widely scattered across the Hikurangi Plateau are interpreted to have formed at 99–89 Ma immediately following Hikurangi Plateau jamming of the Gondwana convergent margin at 100 Ma. Volcanism from this period cannot be separately resolved in the seismic reflection data from basement volcanism; hence seamount formation during Manihiki-Hikurangi Plateau emplacement and breakup (125–120 Ma) cannot be ruled out. -
Playing Jigsaw with Large Igneous Provinces a Plate Tectonic
PUBLICATIONS Geochemistry, Geophysics, Geosystems RESEARCH ARTICLE Playing jigsaw with Large Igneous Provinces—A plate tectonic 10.1002/2015GC006036 reconstruction of Ontong Java Nui, West Pacific Key Points: Katharina Hochmuth1, Karsten Gohl1, and Gabriele Uenzelmann-Neben1 New plate kinematic reconstruction of the western Pacific during the 1Alfred-Wegener-Institut Helmholtz-Zentrum fur€ Polar- und Meeresforschung, Bremerhaven, Germany Cretaceous Detailed breakup scenario of the ‘‘Super’’-Large Igneous Province Abstract The three largest Large Igneous Provinces (LIP) of the western Pacific—Ontong Java, Manihiki, Ontong Java Nui Ontong Java Nui ‘‘Super’’-Large and Hikurangi Plateaus—were emplaced during the Cretaceous Normal Superchron and show strong simi- Igneous Province as result of larities in their geochemistry and petrology. The plate tectonic relationship between those LIPs, herein plume-ridge interaction referred to as Ontong Java Nui, is uncertain, but a joined emplacement was proposed by Taylor (2006). Since this hypothesis is still highly debated and struggles to explain features such as the strong differences Correspondence to: in crustal thickness between the different plateaus, we revisited the joined emplacement of Ontong Java K. Hochmuth, [email protected] Nui in light of new data from the Manihiki Plateau. By evaluating seismic refraction/wide-angle reflection data along with seismic reflection records of the margins of the proposed ‘‘Super’’-LIP, a detailed scenario Citation: for the emplacement and the initial phase of breakup has been developed. The LIP is a result of an interac- Hochmuth, K., K. Gohl, and tion of the arriving plume head with the Phoenix-Pacific spreading ridge in the Early Cretaceous. The G. -
Massive Basalt Flows on the Southern Flank of Tamu Massif, Shatsky Rise: a Reappraisal of ODP Site 1213 Basement Units1 A.A.P
Sager, W.W., Sano, T., Geldmacher, J., and the Expedition 324 Scientists Proceedings of the Integrated Ocean Drilling Program, Volume 324 Massive basalt flows on the southern flank of Tamu Massif, Shatsky Rise: a reappraisal of ODP Site 1213 basement units1 A.A.P. Koppers,2 T. Sano, 3 J.H. Natland,3 M. Widdowson,3 R. Almeev,3 A.R. Greene,3 D.T. Murphy,3 A. Delacour,3 M. Miyoshi,3 K. Shimizu,3 S. Li,3 N. Hirano,3 J. Geldmacher,3 and the Expedition 324 Scientists3 Chapter contents Abstract Abstract . 1 Drilling during Ocean Drilling Program Leg 198 at Site 1213 re- covered three massive basalt units (8–15 m thick) from the south- Introduction . 1 ern flank of Tamu Massif at Shatsky Rise. Originally, these igneous Volcanology and igneous petrology of Site 1213. 2 units were interpreted to represent three diabase sills. During In- Interpretation and conclusions. 5 tegrated Ocean Drilling Program Expedition 324, this core was re- Acknowledgments. 6 described leading to the new conclusion that these diabase units References . 6 represent three submarine massive basalt flows. These massive Figures . 8 submarine flows were probably emplaced as inflated compound Table . 20 sheet flows during eruptions similar to those in large oceanic pla- teaus and continental flood basalts. Introduction The main objective of Integrated Ocean Drilling Program (IODP) Expedition 324 was to test competing mantle plume and plate tectonic models for ocean plateau formation at Shatsky Rise (Fig. F1). In these tests, determining the timing, duration, and source of volcanism at Shatsky Rise is of pivotal importance to under- stand the origin of this oceanic plateau. -
1. Shatsky Rise: Seismic Stratigraphy and Sedimentary Record of Pacific Paleoceanography Since the Early Cretaceous1
Natland, J.H., Storms, M.A., et al., 1993 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 132 1. SHATSKY RISE: SEISMIC STRATIGRAPHY AND SEDIMENTARY RECORD OF PACIFIC PALEOCEANOGRAPHY SINCE THE EARLY CRETACEOUS1 William V. Sliter2 and Glenn R. Brown3 ABSTRACT Shatsky Rise consists of three highs arranged in a linear trend more than 1300 km long. Shatsky Plateau, the southernmost and largest of three highs is represented by an exposed basement high of presumed Late Jurassic age flanked by a sedimentary sequence of at least Cretaceous and Cenozoic age that reaches a maximum thickness of more than 1100 m. Drilling on Shatsky Rise is restricted to eight DSDP and ODP sites on the southern plateau that partially penetrated the sedimentary sequence. Leg 132 seismic profiles and previous seismic records from Shatsky Plateau reveal a five-part seismic section that is correlated with the drilling record and used to interpret the sedimentary history of the rise. The seismic sequence documents the transit of Shatsky Plateau beneath the equatorial divergence in the Late Cretaceous by horizontal plate motion from an original location in the Southern Hemisphere. Unconformities and lithologic changes bounding several of the seismic units are correlated with pale- oceanographic changes that resulted in erosional events near the Barremian/Aptian, Cenomanian/Turonian, and Paleogene/Neo- gene boundaries. INTRODUCTION Plateau, is the largest with a length of about 700 km and a width of about 300 km. All previous DSDP and ODP drill sites are located on Shatsky Rise, the second largest oceanic plateau in the Pacific the southern plateau (Fig. -
Scientists Confirm Existence of Largest Single Volcano on Earth (Update) 5 September 2013
Scientists confirm existence of largest single volcano on Earth (Update) 5 September 2013 Tamu Massif did indeed erupt from a single source near the center. "Tamu Massif is the biggest single shield volcano ever discovered on Earth," Sager said. "There may be larger volcanoes, because there are bigger igneous features out there such as the Ontong Java Plateau, but we don't know if these features are one volcano or complexes of volcanoes." MCS re?ection Line A–B, across the axis of Tamu Massif. Credit: Nature A University of Houston (UH) professor led a team of scientists to uncover the largest single volcano yet documented on Earth. Covering an area roughly equivalent to the British Isles or the state of New Mexico, this volcano, dubbed the Tamu Massif, is nearly as big as the giant volcanoes of Mars, placing it among the largest in the Solar System. William Sager, a professor in the Department of Earth and Atmospheric Sciences at UH, first began studying the volcano about 20 years ago at Texas A&M's College of Geosciences. Sager and his team's findings appear in the Sept. 8 issue of Nature Geoscience, the monthly multi-disciplinary journal reflecting disciplines within the geosciences. Located about 1,000 miles east of Japan, Tamu Massif is the largest feature of Shatsky Rise, an underwater mountain range formed 130 to 145 million years ago by the eruption of several underwater volcanoes. Until now, it was unclear whether Tamu Massif was a single volcano, or a IODP technician Margaret Hastedt labels pieces of core composite of many eruption points. -
Subsidence and Growth of Pacific Cretaceous Plateaus
ELSEVIER Earth and Planetary Science Letters 161 (1998) 85±100 Subsidence and growth of Paci®c Cretaceous plateaus Garrett Ito a,Ł, Peter D. Clift b a School of Ocean and Earth Science and Technology, POST 713, University of Hawaii at Manoa, Honolulu, HI 96822, USA b Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA Received 10 November 1997; revised version received 11 May 1998; accepted 4 June 1998 Abstract The Ontong Java, Manihiki, and Shatsky oceanic plateaus are among the Earth's largest igneous provinces and are commonly believed to have erupted rapidly during the surfacing of giant heads of initiating mantle plumes. We investigate this hypothesis by using sediment descriptions of Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) drill cores to constrain plateau subsidence histories which re¯ect mantle thermal and crustal accretionary processes. We ®nd that total plateau subsidence is comparable to that expected of normal sea¯oor but less than predictions of thermal models of hotspot-affected lithosphere. If crustal emplacement was rapid, then uncertainties in paleo-water depths allow for the anomalous subsidence predicted for plumes with only moderate temperature anomalies and volumes, comparable to the sources of modern-day hotspots such as Hawaii and Iceland. Rapid emplacement over a plume head of high temperature and volume, however, is dif®cult to reconcile with the subsidence reconstructions. An alternative possibility that reconciles low subsidence over a high-temperature, high-volume plume source is a scenario in which plateau subsidence is the superposition of (1) subsidence due to the cooling of the plume source, and (2) uplift due to prolonged crustal growth in the form of magmatic underplating. -
3.16 Oceanic Plateaus A.C.Kerr Cardiffuniversity,Wales,UK
3.16 Oceanic Plateaus A.C.Kerr CardiffUniversity,Wales,UK 3.16.1 INTRODUCTION 537 3.16.2 FORMATION OF OCEANIC PLATEAUS 539 3.16.3 PRESERVATIONOFOCEANIC PLATEAUS 540 3.16.4GEOCHEMISTRY OF CRETACEOUSOCEANICPLATEAUS 540 3.16.4.1 GeneralChemicalCharacteristics 540 3.16.4.2 MantlePlumeSource Regions ofOceanic Plateaus 541 3.16.4.3 Caribbean–ColombianOceanic Plateau(, 90 Ma) 544 3.16.4.4OntongJavaPlateau(, 122 and , 90 Ma) 548 3.16.5THE INFLUENCE OF CONTINENTALCRUST ON OCEANIC PLATEAUS 549 3.16.5.1 The NorthAtlantic Igneous Province ( , 60 Ma to Present Day) 549 3.16.5.2 The KerguelenIgneous Province ( , 133 Ma to Present Day) 550 3.16.6 IDENTIFICATION OF OCEANIC PLATEAUS IN THE GEOLOGICAL RECORD 551 3.16.6.1 Diagnostic FeaturesofOceanic Plateaus 552 3.16.6.2 Mafic Triassic Accreted Terranesinthe NorthAmericanCordillera 553 3.16.6.3 Carboniferous to CretaceousAccreted Oceanic Plateaus inJapan 554 3.16.7 PRECAMBRIAN OCEANICPLATEAUS 556 3.16.8ENVIRONMENTAL IMPACT OF OCEANICPLATEAU FORMATION557 3.16.8.1 Cenomanian–TuronianBoundary (CTB)Extinction Event 558 3.16.8.2 LinksbetweenCTB Oceanic PlateauVolcanism andEnvironmentalPerturbation 558 3.16.9 CONCLUDING STATEMENTS 560 REFERENCES 561 3.16.1 INTRODUCTION knowledge ofthe oceanbasins hasimproved over the last 25years,many moreoceanic plateaus Although the existence oflarge continentalflood havebeenidentified (Figure1).Coffinand basalt provinceshasbeenknownfor some Eldholm (1992) introduced the term “large igneous considerabletime, e.g.,Holmes(1918),the provinces” (LIPs) asageneric term encompassing recognition thatsimilarfloodbasalt provinces oceanic plateaus,continentalfloodbasalt alsoexist belowthe oceans isrelatively recent. In provinces,andthoseprovinceswhich form at the early 1970s increasingamounts ofevidence the continent–oceanboundary (volcanic rifted fromseismic reflection andrefraction studies margins). -
(2020) Pūhāhonu: Earth's Biggest and Hottest Shield Volcano. Earth And
Earth and Planetary Science Letters 542 (2020) 116296 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Puh¯ ahonu:¯ Earth’s biggest and hottest shield volcano ∗ Michael O. Garcia a, , Jonathan P. Tree a, Paul Wessel a, John R. Smith b a Department of Earth Sciences, University of Hawai‘i at Manoa,¯ Honolulu, HI 96822, USA b Department of Oceanography, University of Hawai‘i at Manoa,¯ Honolulu, HI 96822, USA a r t i c l e i n f o a b s t r a c t Article history: New bathymetric and gravity mapping, refined volume calculations and petrologic analyses show that Received 22 November 2019 the Hawaiian volcano Puh¯ ahonu¯ is the largest and hottest shield volcano on Earth. This ∼12.5-14.1 Ma Received in revised form 5 April 2020 volcano in the northwest Hawaiian Ridge (NWHR) is twice the size of Mauna Loa volcano (148 ± 29 vs. Accepted 18 April 2020 3 3 74.0 × 10 km ), which was assumed to be not only the largest Hawaiian volcano but also the largest Available online xxxx known shield volcano. We considered four testable mechanisms to increase magma production, including Editor: R. Dasgupta 1) thinner lithosphere, 2) slower propagation rate, 3) more fertile source, and 4) hotter mantle. The first Keywords: three of these have been ruled out. The lithosphere was old (∼88 Myrs) when Puh¯ ahonu¯ was formed, Hawaii and thus, too thick and cold to allow for greater extents of partial melting. The propagation rate was volume relatively fast when it erupted (87 km/Myr), so this is another unlikely reason. -
S41598-020-76691-1 1 Vol.:(0123456789)
www.nature.com/scientificreports OPEN Rifting of the oceanic Azores Plateau with episodic volcanic activity B. Storch1*, K. M. Haase1, R. H. W. Romer1, C. Beier1,2 & A. A. P. Koppers3 Extension of the Azores Plateau along the Terceira Rift exposes a lava sequence on the steep northern fank of the Hirondelle Basin. Unlike typical tholeiitic basalts of oceanic plateaus, the 1.2 km vertical submarine stratigraphic profle reveals two successive compositionally distinct basanitic to alkali basaltic eruptive units. The lower unit is volumetrically more extensive with ~ 1060 m of the crustal profle forming between ~ 2.02 and ~ 1.66 Ma, followed by a second unit erupting the uppermost ~ 30 m of lavas in ~ 100 kyrs. The age of ~ 1.56 Ma of the youngest in-situ sample at the top of the profle implies that the 35 km-wide Hirondelle Basin opened after this time along normal faults. This rifting phase was followed by alkaline volcanism at D. João de Castro seamount in the basin center indicating episodic volcanic activity along the Terceira Rift. The mantle source compositions of the two lava units change towards less radiogenic Nd, Hf, and Pb isotope ratios. A change to less SiO2-undersaturated magmas may indicate increasing degrees of partial melting beneath D. João de Castro seamount, possibly caused by lithospheric thinning within the past 1.5 million years. Our results suggest that rifting of oceanic lithosphere alternates between magmatically and tectonically dominated phases. Oceanic plateaus with a crustal thickness to 30 km cover large areas in the oceans and these bathymetric swells afect oceanic currents and marine life 1,2. -
Active Continental Margin
Encyclopedia of Marine Geosciences DOI 10.1007/978-94-007-6644-0_102-2 # Springer Science+Business Media Dordrecht 2014 Active Continental Margin Serge Lallemand* Géosciences Montpellier, University of Montpellier, Montpellier, France Synonyms Convergent boundary; Convergent margin; Destructive margin; Ocean-continent subduction; Oceanic subduction zone; Subduction zone Definition An active continental margin refers to the submerged edge of a continent overriding an oceanic lithosphere at a convergent plate boundary by opposition with a passive continental margin which is the remaining scar at the edge of a continent following continental break-up. The term “active” stresses the importance of the tectonic activity (seismicity, volcanism, mountain building) associated with plate convergence along that boundary. Today, people typically refer to a “subduction zone” rather than an “active margin.” Generalities Active continental margins, i.e., when an oceanic plate subducts beneath a continent, represent about two-thirds of the modern convergent margins. Their cumulated length has been estimated to 45,000 km (Lallemand et al., 2005). Most of them are located in the circum-Pacific (Japan, Kurils, Aleutians, and North, Middle, and South America), Southeast Asia (Ryukyus, Philippines, New Guinea), Indian Ocean (Java, Sumatra, Andaman, Makran), Mediterranean region (Aegea, Cala- bria), or Antilles. They are generally “active” over tens (Tonga, Mariana) or hundreds (Japan, South America) of millions of years. This longevity has consequences on their internal structure, especially in terms of continental growth by tectonic accretion of oceanic terranes, or by arc magmatism, but also sometimes in terms of continental consumption by tectonic erosion. Morphology A continental margin generally extends from the coast down to the abyssal plain (see Fig. -
Geochemistry and Age of Shatsky, Hess, and Ojin Rise Seamounts: Implications for a Connection Between the Shatsky and Hess Rises
Accepted Manuscript Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications for a connection between the Shatsky and Hess Rises Maria Luisa G. Tejada, Jörg Geldmacher, Folkmar Hauff, Daniel Heaton, Anthony A.P. Koppers, Dieter Garbe-Schönberg, Kaj Hoernle, Ken Heydolph, William W. Sager PII: S0016-7037(16)30165-X DOI: http://dx.doi.org/10.1016/j.gca.2016.04.006 Reference: GCA 9701 To appear in: Geochimica et Cosmochimica Acta Received Date: 4 September 2015 Accepted Date: 1 April 2016 Please cite this article as: Tejada, M.L.G., Geldmacher, J., Hauff, F., Heaton, D., Koppers, A.A.P., Garbe- Schönberg, D., Hoernle, K., Heydolph, K., Sager, W.W., Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications for a connection between the Shatsky and Hess Rises, Geochimica et Cosmochimica Acta (2016), doi: http://dx.doi.org/10.1016/j.gca.2016.04.006 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 1 Geochemistry and Age of Shatsky, Hess, and Ojin Rise seamounts: Implications 2 for a connection between the Shatsky and Hess Rises 3 Maria Luisa G. Tejada a,b*, Jörg Geldmacher c, Folkmar Hauff c, Daniel Heaton d, Anthony A. -
Connecting the Deep Earth and the Atmosphere
In Mantle Convection and Surface Expression (Cottaar, S. et al., eds.) AGU Monograph 2020 (in press) Connecting the Deep Earth and the Atmosphere Trond H. Torsvik1,2, Henrik H. Svensen1, Bernhard Steinberger3,1, Dana L. Royer4, Dougal A. Jerram1,5,6, Morgan T. Jones1 & Mathew Domeier1 1Centre for Earth Evolution and Dynamics (CEED), University of Oslo, 0315 Oslo, Norway; 2School of Geosciences, University of Witwatersrand, Johannesburg 2050, South Africa; 3Helmholtz Centre Potsdam, GFZ, Telegrafenberg, 14473 Potsdam, Germany; 4Department of Earth and Environmental Sciences, Wesleyan University, Middletown, Connecticut 06459, USA; 5DougalEARTH Ltd.1, Solihull, UK; 6Visiting Fellow, Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia. Abstract Most hotspots, kimberlites, and large igneous provinces (LIPs) are sourced by plumes that rise from the margins of two large low shear-wave velocity provinces in the lowermost mantle. These thermochemical provinces have likely been quasi-stable for hundreds of millions, perhaps billions of years, and plume heads rise through the mantle in about 30 Myr or less. LIPs provide a direct link between the deep Earth and the atmosphere but environmental consequences depend on both their volumes and the composition of the crustal rocks they are emplaced through. LIP activity can alter the plate tectonic setting by creating and modifying plate boundaries and hence changing the paleogeography and its long-term forcing on climate. Extensive blankets of LIP-lava on the Earth’s surface can also enhance silicate weathering and potentially lead to CO2 drawdown (cooling), but we find no clear relationship between LIPs and post-emplacement variation in atmospheric CO2 proxies on very long (>10 Myrs) time- scales.