Journal articles: 'Sea-floor spreading'

1

Dutch, Steven I. "An Advanced Sea-Floor Spreading Model." Journal of Geological Education 34, no. 1 (January 1986): 18–20. http://dx.doi.org/10.5408/0022-1368-34.1.18.

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2

Mutter, J. C. "Seismic Imaging of Sea-Floor Spreading." Science 258, no. 5087 (November 27, 1992): 1442–43. http://dx.doi.org/10.1126/science.258.5087.1442.

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Almalki, Khalid A., Peter G. Betts, and Laurent Ailleres. "Episodic sea-floor spreading in the Southern Red Sea." Tectonophysics 617 (March 2014): 140–49. http://dx.doi.org/10.1016/j.tecto.2014.01.030.

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4

Roest, W. R., and S. P. Srivastava. "Sea-floor spreading in the Labrador Sea: A new reconstruction." Geology 17, no. 11 (1989): 1000. http://dx.doi.org/10.1130/0091-7613(1989)017<1000:sfsitl>2.3.co;2.

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AGER, D. V. "Why do we call it ‘sea floor spreading’?" Geology Today 8, no. 4 (July 1992): 127. http://dx.doi.org/10.1111/j.1365-2451.1992.tb00384.x.

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6

Tolstoy, M., J. P. Cowen, E. T. Baker, D. J. Fornari, K. H. Rubin, T. M. Shank, F. Waldhauser, et al. "A Sea-Floor Spreading Event Captured by Seismometers." Science 314, no. 5807 (November 23, 2006): 1920–22. http://dx.doi.org/10.1126/science.1133950.

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7

TAMAKI, Kensaku. "Progress of the study of the sea-floor spreading." Journal of Geography (Chigaku Zasshi) 98, no. 3 (1989): 193–202. http://dx.doi.org/10.5026/jgeography.98.3_193.

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8

Müller, R. Dietmar, Walter R. Roest, and Jean-Yves Royer. "Asymmetric sea-floor spreading caused by ridge–plume interactions." Nature 396, no. 6710 (December 1998): 455–59. http://dx.doi.org/10.1038/24850.

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9

Taylor, Brian, Kirsten Zellmer, Fernando Martinez, and Andrew Goodliffe. "Sea-floor spreading in the Lau back-arc basin." Earth and Planetary Science Letters 144, no. 1-2 (October 1996): 35–40. http://dx.doi.org/10.1016/0012-821x(96)00148-3.

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10

Picard, M. Dane. "Harry Hammond Hess and the Theory of Sea-Floor Spreading." Journal of Geological Education 37, no. 5 (November 1989): 346–49. http://dx.doi.org/10.5408/0022-1368-37.5.346.

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11

Katz, Richard F., Rolf Ragnarsson, and Eberhard Bodenschatz. "Tectonic microplates in a wax model of sea-floor spreading." New Journal of Physics 7 (February 2, 2005): 37. http://dx.doi.org/10.1088/1367-2630/7/1/037.

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12

Kikawa, E., and K. Ozawa. "Contribution of Oceanic Gabbros to Sea-Floor Spreading Magnetic Anomalies." Science 258, no. 5083 (October 30, 1992): 796–99. http://dx.doi.org/10.1126/science.258.5083.796.

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13

Kawahata, Hodaka, and Toshio Furuta. "Sub-sea-floor hydrothermal alteration in the Galápagos Spreading Center." Chemical Geology 49, no. 1-3 (June 1985): 259–74. http://dx.doi.org/10.1016/0009-2541(85)90160-3.

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14

Tunnicliffe, Verena, and C. Mary R. Fowler. "Influence of sea-floor spreading on the global hydrothermal vent fauna." Nature 379, no. 6565 (February 1996): 531–33. http://dx.doi.org/10.1038/379531a0.

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15

Makris, J., and A. Ginzburg. "The Afar Depression: transition between continental rifting and sea-floor spreading." Tectonophysics 141, no. 1-3 (September 1987): 199–214. http://dx.doi.org/10.1016/0040-1951(87)90186-7.

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16

Taylor, Brian, Andrew Goodliffe, Fernando Martinez, and Richard Hey. "Continental rifting and initial sea-floor spreading in the Woodlark basin." Nature 374, no. 6522 (April 1995): 534–37. http://dx.doi.org/10.1038/374534a0.

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17

Metzger, Ellen P. "Building a Topographic Model Submarine Mountains A Model of Sea Floor Spreading." Paleontological Society Papers 2 (October 1996): 69–99. http://dx.doi.org/10.1017/s108933260000317x.

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The Activities that follow are from The Best of BAESI, a collection of 19 hand-on lessons modeled by teacher-participants in the Bay Area Earth Science Institute. BAESI was founded in 1990 at San Jose University. A non-profit organization supported by the National Science Foundation, San Jose State University, and a consortium of government, corporate, and academic partners, BAESI is built on the following observations:

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18

Baksi, Ajoy K. "Concordant sea-floor spreading rates obtained from geochronology, astrochronology and space geodesy." Geophysical Research Letters 21, no. 2 (January 15, 1994): 133–36. http://dx.doi.org/10.1029/93gl03534.

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19

Todorovska, Maria I., and Mihailo D. Trifunac. "Generation of tsunamis by a slowly spreading uplift of the sea floor." Soil Dynamics and Earthquake Engineering 21, no. 2 (February 2001): 151–67. http://dx.doi.org/10.1016/s0267-7261(00)00096-8.

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20

Schroetter, Jean-Michel, Philippe Pagé, Jean H. Bédard, Alain Tremblay, and Valérie Bécu. "Forearc extension and sea-floor spreading in the Thetford Mines Ophiolite Complex." Geological Society, London, Special Publications 218, no. 1 (2003): 231–51. http://dx.doi.org/10.1144/gsl.sp.2003.218.01.13.

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21

Miles, Peter R., and Walter R. Roest. "Earliest sea-floor spreading magnetic anomalies in the north Arabian Sea and the ocean-continent transition." Geophysical Journal International 115, no. 3 (December 1993): 1025–31. http://dx.doi.org/10.1111/j.1365-246x.1993.tb01507.x.

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Nelson, Gareth. "A Decade of Challenge the Future of Biogeography." Earth Sciences History 4, no. 2 (January 1, 1985): 187–96. http://dx.doi.org/10.17704/eshi.4.2.c347xp1671w4m0n0.

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According to Croizat's global synthesis, the main biogeographic patterns include trans-Atlantic, trans-Pacific, trans-Indoceanic, Boreal, and Austral. Geological and geophysical theories vary, but agree that sea-floor spreading in the Pacific is different in its effect from that in other ocean basins. The difference allows for radial expansion of the basin and not merely east-west displacement of continental areas. Biogeographic data suggest that bipolar (boreal + austral) distributions are to be reckoned among the results of sea-floor spreading in the Pacific. Data from one group of inshore fishes (family Engraulidae) exemplify this notion and add, as terminal parts of the differentiation of the Pacific Basin, trans-Panama marine vicariance and a collateral occurrence in freshwater of tropical South America. These findings corroborate Croizat's synthesis. They suggest that the critical evaluation of that synthesis will be the main task of biogeography over the next decade. They indicate that within the area of systematics, evaluation will require a cladistic approach and the elimination of paraphyletic groups from classification.

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23

Heller, Paul L., Don L. Anderson, and Charles L. Angevine. "Is the middle Cretaceous pulse of rapid sea-floor spreading real or necessary?" Geology 24, no. 6 (1996): 491. http://dx.doi.org/10.1130/0091-7613(1996)024<0491:itmcpo>2.3.co;2.

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24

Bernoulli, Daniel, and Hugh C. Jenkyns. "Ophiolites in ocean–continent transitions: From the Steinmann Trinity to sea-floor spreading." Comptes Rendus Geoscience 341, no. 5 (May 2009): 363–81. http://dx.doi.org/10.1016/j.crte.2008.09.009.

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25

Farrar, Edward, and John M. Dixon. "Ridge subduction: kinematics and implications for the nature of mantle upwelling." Canadian Journal of Earth Sciences 30, no. 5 (May 1, 1993): 893–907. http://dx.doi.org/10.1139/e93-074.

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Ridge subduction follows the approach of an oceanic spreading centre towards a trench and subduction of the leading oceanic plate beneath the overriding plate. There are four possible kinematic scenarios: (1) welding of the trailing and overriding plates (e.g., Aluk–Antarctic Ridge beneath Antarctica); (2) slower subduction of the trailing plate (e.g., Nazca–Antarctic Ridge beneath Chile and Pacific–Izanagi Ridge beneath Japan); (3) transform motion between the trailing and overriding plates (e.g., San Andreas Transform); or (4) divergence between the overriding and trailing plates (e.g., Pacific – North America). In case 4, the divergence may be accommodated in two ways: the overriding plate may be stretched (e.g., Basin and Range Province extension, which has brought the continental margin into collinearity (and, therefore, transform motion) with the Pacific – North America relative motion); or divergence may occur at the continental margin and be manifest as a change in rate and direction of sea-floor spreading because the pair of spreading plates changes (e.g., from Pacific–Farallon to Pacific – North America), spawning a secondary spreading centre (i.e., Gorda – Juan de Fuca – Explorer ridge system) that migrates away from the overriding plate.Mantle upwelling associated with sea-floor spreading ridges is widely regarded as a passive consequence, rather than an active cause, of plate divergence. Geological and geophysical phenomena attendant to ridge–trench interaction suggest that regardless of the kinematic relations among the three plates, a thermal anomaly formerly associated with the ridge migrates beneath the overriding plate. The persistence of this thermal anomaly demonstrates that active mantle upwelling may continue for tens of millions of years after ridge subduction. Thus, regardless of whether the mantle upwelling was active or passive at its origin, it becomes active if the spreading continues for sufficient time and, thus, must contribute to the driving mechanism of plate tectonics.

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Swedan, N. H. "Energy of plate tectonics calculation and projection." Solid Earth Discussions 5, no. 1 (February 14, 2013): 135–61. http://dx.doi.org/10.5194/sed-5-135-2013.

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Abstract. Mathematics and observations suggest that the energy of the geological activities resulting from plate tectonics is equal to the latent heat of melting, calculated at mantle's pressure, of the new ocean crust created at midocean ridges following sea floor spreading. This energy varies with the temperature of ocean floor, which is correlated with surface temperature. The objective of this manuscript is to calculate the force that drives plate tectonics, estimate the energy released, verify the calculations based on experiments and observations, and project the increase of geological activities with surface temperature rise caused by climate change.

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Jakobsson, Martin, Matt O'Regan, Carl-Magnus Mörth, Christian Stranne, Elizabeth Weidner, Jim Hansson, Richard Gyllencreutz, et al. "Potential links between Baltic Sea submarine terraces and groundwater seeping." Earth Surface Dynamics 8, no. 1 (January 3, 2020): 1–15. http://dx.doi.org/10.5194/esurf-8-1-2020.

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Abstract. Submarine groundwater discharge (SGD) influences ocean chemistry, circulation, and the spreading of nutrients and pollutants; it also shapes sea floor morphology. In the Baltic Sea, SGD was linked to the development of terraces and semicircular depressions mapped in an area of the southern Stockholm archipelago, Sweden, in the 1990s. We mapped additional parts of the Stockholm archipelago, areas in Blekinge, southern Sweden, and southern Finland using high-resolution multibeam sonars and sub-bottom profilers to investigate if the sea floor morphological features discovered in the 1990s are widespread and to further address the hypothesis linking their formation to SGD. Sediment coring and sea floor photography conducted with a remotely operated vehicle (ROV) and divers add additional information to the geophysical mapping results. We find that terraces, with general bathymetric expressions of about 1 m and lateral extents of sometimes >100 m, are widespread in the surveyed areas of the Baltic Sea and are consistently formed in glacial clay. Semicircular depressions, however, are only found in a limited part of a surveyed area east of the island of Askö, southern Stockholm archipelago. While submarine terraces can be produced by several processes, we interpret our results to be in support of the basic hypothesis of terrace formation initially proposed in the 1990s; i.e. groundwater flows through siltier, more permeable layers in glacial clay to discharge at the sea floor, leading to the formation of a sharp terrace when the clay layers above seepage zones are undermined enough to collapse. By linking the terraces to a specific geologic setting, our study further refines the formation hypothesis and thereby forms the foundation for a future assessment of SGD in the Baltic Sea that may use marine geological mapping as a starting point. We propose that SGD through the submarine sea floor terraces is plausible and could be intermittent and linked to periods of higher groundwater levels, implying that to quantify the contribution of freshwater to the Baltic Sea through this potential mechanism, more complex hydrogeological studies are required.

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Grushevskaya, O. V., A. V. Soloviev, E. A. Vasilyeva, E. P. Petrushina, I. V. Aksenov, A. R. Yusupova, S. V. Shimanskiy, and I. N. Peshkova. "Tectonics of the Continental Barents Sea Shelf (Russia): Formation Stages of Basement and Sedimentary Cover." Геотектоника, no. 6 (November 1, 2023): 43–77. http://dx.doi.org/10.31857/s0016853x23060048.

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Based on the results of field complex geophysical studies in the northwestern part of the Russian sector of the Barents Sea shelf, as well as on the processing and comprehensive interpretation of new and retrospective geophysical materials in the volume of 25 500 linear kilometers and deep well drilling data in the section of the Barents Sea sedimentary cover identified regional tectonostratigraphic units: (i) Paleozoic complex (between reflecting horizons VI(PR? ) and I2(P‒T)); (ii) the Triassic complex (between reflecting horizons I2(P‒T) and B(T‒J)); (iii) the Jurassic complex (between reflecting horizons B(T‒J) and V′(J3‒K1)); (iv) the Cretaceous‒Cenozoic complex (between reflecting V′(J3‒K1) and the Barents sea floor). According to the structural analysis’ results, three structural floors are established: the lower structural floor, which includes Riphean terrigenous-affusive sediments and Lower Paleozoic‒Lower Permian terrigenous-carbonate sediments; the middle structural floor is formed mainly by carbonate sediments of Upper Devonian‒Lower Permian; the upper structural floor combines terrigenous sediments of Lower and Upper Permian, Mesozoic and Cenozoic sediments. The authors present a new tectonic model of the Barents Sea region, including elements of all structural floors with subfloors. In accordance with the tectonic zoning, paleostructural and paleotectonic analyses, the article outlines the main stages of the Barents Sea shelf development: stage of the Late Proterozoic compression and Early-Middle Paleozoic continental rifting (I), Late Paleozoic stabilization stage (II), Early Mesozoic tectogenesis stage (III), Middle Mesozoic thermal subsidence stage (IV), Late Jurassic stabilization stage (V), Cretaceous sagging stage (VI) and the final stage as a Cenozoic uplift over a large part of the Barents Sea shelf (VII). In the northwestern part of the Russian sector of the Barents Sea shelf, synchronous dipping of the sedimentary cover basement took place, associated with spreading and formation of the Arctic Ocean.

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Hancock, J. M., and P. F. Rawson. "Cretaceous." Geological Society, London, Memoirs 13, no. 1 (1992): 131–39. http://dx.doi.org/10.1144/gsl.mem.1992.013.01.13.

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AbstractEarly CretaceousThe Cretaceous Period lasted for about 70 million years. During this time there was a major change in the sedimentary history of the area as tectonism died down and deposition started of an extensive blanket of coccolith ooze: the Chalk. The change took place mainly over a brief interval across the Albian/Cenomanian (Lower/Upper Cretaceous) boundary, at about 95 Ma. Until that time crustal extension along the Arctic-North Atlantic megarifts continued to influence the tectonic evolution of northwest Europe (Ziegler 1982, 1988). This tensional régime caused rifting and block faulting, particularly across the Jurassic-Cretaceous boundary (Late Cimmerian movements) and in the mid Aptian (Austrian phase). During the latter phase, sea-floor spreading commenced in the Biscay and central Rockall Rifts. The northern part of the Rockall Rift began to widen too, possibly by crustal stretching rather than sea-floor spreading (Ziegler 1988, p. 75). During the Albian the regional pattern began to change and by the beginning of the Cenomanian rifting had effectively ceased away from the Rockall/Faeroe area.Most of the Jurassic sedimentary basins continued as depositional areas during the Early Cretaceous, but the more extensive preservation of Lower Cretaceous sediments provides firmer constraints on some of the geographical reconstructions. The marked sea-level fall across the Jurassic-Cretaceous boundary isolated the more southerly basins as areas of non-marine sedimentation, and it was not until the beginning of the Aptian that they became substantially marine.The extent of emergence of highs in the North Sea area is difficult to assess, especially where

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Goričan, Špela, Josip Halamić, Tonći Grgasović, and Tea Kolar-Jurkovšek. "Stratigraphic evolution of Triassic arc-backarc system in northwestern Croatia." Bulletin de la Société Géologique de France 176, no. 1 (January 1, 2005): 3–22. http://dx.doi.org/10.2113/176.1.3.

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Abstract Middle Triassic arc-related extensional tectonics in the western Tethys generated a complex pattern of intra-and backarc basins. We studied volcano-sedimentary successions of subsided continental-margin blocks (Mts. Žumberak and Ivanščica) and of dismembered incomplete ophiolite sequences interpreted as remnants of a backarc basin (Mts. Medvednica and Kalnik) in northwestern Croatia. We dated the successions with radiolarians, conodonts, foraminifers, algae, and sponges. The continental margin experienced a phase of accelerated subsidence in the late Anisian that was approximately coincident with the onset of intermediate and acidic volcanism; pelagic sediments with volcaniclastics accumulated atop subsided carbonate platforms. These relatively shallow basins were later infilled completely by prograding platforms in the late Ladinian-Carnian. In the backarc basin, sea-floor spreading initiated near the Anisian-Ladinian boundary and continued into the late Carnian. Pillow basalts were erupted and interlayered with radiolarian cherts and shales. The studied area was a part of a larger Triassic arc-backarc system preserved in the southern Alps, Alpine-Carpathian Belt, Dinarides, and Hellenides. Volcano-sedimentary successions of Mts. Medvednica and Kalnik are relics of the Meliata-Maliak backarc basin. In comparison to other previously dated oceanic remnants of this system, the longest continuous sea-floor spreading is now documented in one restricted tectonic unit.

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Carbotte, S. M., J. M. Dixon, E. Farrar, E. E. Davis, and R. P. Riddihough. "Geological and geophysical characteristics of the Tuzo Wilson Seamounts: implications for plate geometry in the vicinity of the Pacific – North America – Explorer triple junction." Canadian Journal of Earth Sciences 26, no. 11 (November 1, 1989): 2365–84. http://dx.doi.org/10.1139/e89-202.

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SeaMARC II imagery, SEABEAM bathymetry, seismic reflection profiles, and gravity and magnetic data are used to establish the tectonic significance of the Tuzo Wilson Seamounts, two submarine volcanic edifices located southwest of the southern end of the Queen Charlotte transform fault. SeaMARC II imagery reveals a parallel transform fault, an extension of the Revere–Dellwood Fault, bordering the southwest end of the Dell wood Knolls and terminating at the southwest end of the Tuzo Wilson Seamounts. This transform-fault system links spreading at the north end of Explorer Ridge to extension at the Tuzo Wilson Seamounts. An inactive continuation of this transform 50 km to the northwest of Tuzo Wilson Seamounts is inferred from seismic profiles. Between Dellwood Knolls and Tuzo Wilson Seamounts, this transform fault has offset Pleistocene (ca. 10 000 a) sea-bed features in a right-lateral sense by 250 m and has offset part of the Dellwood Knolls volcanic edifice by 6–8 km. Numerous normal faults at the Tuzo Wilson Seamounts and Dellwood Knolls are roughly orthogonal to the Queen Charlotte and Revere–Dellwood transforms and indicate rifting in an extensional jog between the transforms. Seismic profiles reveal sediments and basement back-tilted northwest and southeast away from the Tuzo Wilson Seamounts, also consistent with extension. Acoustic imagery indicates that the Tuzo Wilson Seamounts are surrounded by basalt flows that are largely free of sediment cover and thus postdate recent rapid sedimentation (< 10 000 a). In contrast, few of the flows around Dellwood Knolls are free of sediment. Basalts from the Tuzo Wilson Seamounts have high magnetizations (average 35 A/m) and are free of manganese encrustation. Tuzo Wilson Seamounts have a + 1000 nT magnetic anomaly, which can be modelled with normal, high-intensity (up to 40 A/m) magnetization and with geometry and depth matching the topography of the seamounts and surficial basalt flows. Their small, positive free-air gravity is largely accounted for by their topography; no appreciable local density contrast exists below the surrounding sea floor.The Tuzo Wilson Seamounts and Dellwood Knolls are separate sites of sea-floor spreading, although the partition of spreading between them is indeterminate. The 50 km inactive continuation of the Revere–Dellwood transform requires that a total of at least 100 km of sea floor has been created at the Tuzo Wilson and Dellwood spreading centres, probably within the last 2.5 Ma. The sea floor between the Tuzo Wilson Seamounts and Dellwood Knolls either is a separate microplate or is under going distributed strain. The triple junction of the Pacific, North America, and Explorer plates is not a discrete point; rather it occupies the strained and seismically active region between the northern Explorer Ridge and the Tuzo Wilson Seamounts.

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Thiede, J., A. Altenbach, U. Bleil, R. Botz, P. Mudie, S. Pfirman, and E. Sundvor. "Properties and history of the central eastern Arctic sea floor." Polar Record 26, no. 156 (January 1990): 1–6. http://dx.doi.org/10.1017/s0032247400022695.

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ABSTRACTThe deep eastern Arctic basin between the Lomonosov Ridge and the Eurasian continental margin differs from other ocean basins in the very slow spreading of its floor and unusual depositional environment under perennial sea-ice cover. The recent expedition ARK IV/3 of RV Polar stern for the first time made geoscientific investigations from the northern margin of the Barents Sea north to the Nansen-Gakkel Ridge. Much deeper than most other mid-ocean ridges, this ridge is poorly-surveyed, but has a central valley which in places is deeper than 5.5 km, 1–1.5 km below the basin floors on either side. Heat flow in the central part of the valley is very rapid; both basement rocks and overlying sediments showed unexpectedly the influence of intense and long-term hydrothermal activity. The sediments on the northern and southern flanks of the ridge are slightly calcareous pelagic mud layers alternating with carbonate-free horizons, where up to 40% of the sedimentary section is soft mud clasts. Similar mud aggregates were observed on the surface of the multi-year sea ice, appearing to represent a special type of sediment transport by sea ice in the Transpolar Drift. In contrast to the western Arctic, Fram Strait and the Norwegian-Greenland Sea, gravel is rarely found in sediment cores. Recovered cores indicate that icebergs and sea ice carrying coarse sediment seldom rafted detritus to the study area during the last approximately 300,000 years.

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Davis, E. E., and R. G. Currie. "Geophysical observations of the northern Juan de Fuca Ridge system: lessons in sea-floor spreading." Canadian Journal of Earth Sciences 30, no. 2 (February 1, 1993): 278–300. http://dx.doi.org/10.1139/e93-023.

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By virtue of its proximity to the coastline of North America and to numerous oceanographic institutions, the Juan de Fuca Ridge has been the focus of a large number of marine geological, geochemical, and geophysical investigations. Systematic studies began in the early 1960's with the geophysical survey of A. D. Raff and R. G. Mason, which provided much of the foundation for the development of the extraordinarily successful paradigms of sea-floor spreading and plate tectonics. Subsequent systematic and detailed studies of the plates and plate boundaries of the area by investigators from many academic, industrial, and government agencies, including the Geological Survey of Canada, have provided the basis for much of the fundamental understanding we now have of global plate motions and the processes that are involved in the creation of new oceanic crust at sea-floor spreading centres. Much of the success of these studies can be attributed to the geological diversity found along the Juan de Fuca Ridge. Clear examples are present of "normal" volcanically robust ridge segments, deep extensional rift valleys, stable and evolving transform faults, nontransform ridge offsets, propagating rifts, and off-axis seamount chains. Much has been learned about the nature of hydrothermal circulation through intensive studies of the many active hydrothermal systems and mature hydrothermal deposits that occur in both unsedimented and sedimented environments along the ridge. Better understanding of the way that oceanic crust chemically and physically "ages" is emerging from studies on the ridge and ridge flank. A clear history of the evolution of the ridge and of plate motions is provided by the magnetic anomalies mapped over the ridge and adjacent plates. From this history, lessons have been learned about the causes and consequences of plate motions, fragmentation, and internal deformation. Some of the success of these studies can be attributed to the rapidly evolving geophysical tools which provide ever increasing efficiency of operation and resolution. A new phase of study most recently begun involves the deployment of sea-floor geophysical "observatories" that provide a means by which temporal variations and events can be monitored over extended periods of time. These new studies are expected to yield yet another level of understanding of the processes that have produced two thirds of the Earth's surface as well as many important geologic formations in terrestrial settings.

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Mosar, Jon, Gavin Lewis, and TrondH Torsvik. "North Atlantic sea-floor spreading rates: implications for the Tertiary development of inversion structures of the Norwegian–Greenland Sea." Journal of the Geological Society 159, no. 5 (September 2002): 503–15. http://dx.doi.org/10.1144/0016-764901-135.

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LI, Jia-Biao, Wei-Wei DING, Jin-Yao GAO, Zi-Yin WU, and Jie ZHANG. "Cenozoic Evolution Model of the Sea-Floor Spreading in South China Sea: New Constraints from High Resolution Geophysical Data." Chinese Journal of Geophysics 54, no. 6 (November 2011): 894–906. http://dx.doi.org/10.1002/cjg2.1672.

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Wilson, Douglas S. "Confirmation of the astronomical calibration of the magnetic polarity timescale from sea-floor spreading rates." Nature 364, no. 6440 (August 1993): 788–90. http://dx.doi.org/10.1038/364788a0.

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Helmstaedt, Herwart, W. A. Padgham, and John A. Brophy. "Multiple dikes in Lower Kam Group, Yellowknife greenstone belt: Evidence for Archean sea-floor spreading?" Geology 14, no. 7 (1986): 562. http://dx.doi.org/10.1130/0091-7613(1986)14<562:mdilkg>2.0.co;2.

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Dypvik, Henning. "Sedimentary rhythms in the Jurassic and Cretaceous of Svalbard." Geological Magazine 129, no. 1 (January 1992): 93–99. http://dx.doi.org/10.1017/s0016756800008141.

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AbstractThe Janusfjellet Subgroup on Svalbard consists on a 400 to 500 m thick sequence representing shallow marine depositional environments. Coarsening-upward units, often separated by carbonate beds, are commonly found in rhythmic developments. Rhythmicities (285000(?) and 850000(?) years) in the sedimentary sections show periods which may reflect pulses in nearby sea-floor spreading or strike-slip fault regimes. An astronomical control of the cycles cannot be excluded, although such changes most probably should be expected in superimposed episodes of shorter duration.

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Goodliffe, A. M., and B. Taylor. "The boundary between continental rifting and sea-floor spreading in the Woodlark Basin, Papua New Guinea." Geological Society, London, Special Publications 282, no. 1 (2007): 217–38. http://dx.doi.org/10.1144/sp282.11.

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Antonini, P., R. Petrini, and G. Contin. "A segment of sea-floor spreading in the central Red Sea: basalts from the Nereus Deep (23°00′–23°20′N)." Journal of African Earth Sciences 27, no. 1 (July 1998): 107–14. http://dx.doi.org/10.1016/s0899-5362(98)00049-9.

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Larsen, Poul-Henrik, Lars Stemmerik, Troels F. D. Nielsen, and David C. Rex. "Lamprophyric dykes in Revdal, Scoresby Land, East Greenland: conflicting field observations and K-Ar age determinations." Bulletin of the Geological Society of Denmark 38 (April 25, 1990): 1–9. http://dx.doi.org/10.37570/bgsd-1990-38-01.

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Field observations on Iamprophyric dykes in Revdal, Scoresby Land, suggest a Late Permian age and the dykes would thus represent magmatism related to Permian rifting and basin formation, whereas K-Ar age determinations and chemistry suggest a Tertiary age. It is concluded that the dykes probably are Tertiary and never penetrated Upper Permian sediments due to chilling and fracturing at the base of Upper Permian water rich sediments. The dykes most likely belong to a period of alkaline magmatism that followed the onset of sea floor spreading in this part of the North Atlantic around 55 Ma ago.

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PE-PIPER, GEORGIA, and ADONIS PHOTIADES. "Geochemical characteristics of the Cretaceous ophiolitic rocks of Ikaria island, Greece." Geological Magazine 143, no. 4 (June 13, 2006): 417–29. http://dx.doi.org/10.1017/s0016756806002081.

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Scattered occurrences of ophiolitic rocks are widespread in the Cyclades islands of Greece and are important for understanding the later Mesozoic ocean spreading and collisional history of the region, which has been obscured by Cenozoic nappe stacking, metamorphism, plutonism and extension. Ophiolitic rocks in the Upper Tectonic Unit of Ikaria are preserved in a mélange underlying Triassic limestones in the Kefala Unit and in a coarse-grained conglomerate at Faros directly overlying the mid-crustal detachment fault. The geochemistry of these rocks has been determined, their mineralogy investigated by electron microprobe, and K–Ar radiometric dating was carried out. Sole rocks are amphibolite of alkaline basalt protolith. Most ophiolitic samples from Ikaria consist of hornblende gabbro with MORB geochemistry that underwent sea-floor hydration, deformation and metamorphism. The large variation in degree of deformation, grade of metamorphism, and radiometric ages suggest syn-spreading extensional deformation at a slow-spreading ridge. The ophiolitic mélange on Ikaria, because it is unaffected by younger metamorphism, provides clear evidence for Late Cretaceous ocean-crust formation in the Cyclades region.

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McBride, J. H., R. S. White, T. J. Henstock, and R. W. Hobbs. "Complex structure along a Mesozoic sea-floor spreading ridge: BIRPS deep seismic reflection, Cape Verde abyssal plain." Geophysical Journal International 119, no. 2 (November 1994): 453–78. http://dx.doi.org/10.1111/j.1365-246x.1994.tb00134.x.

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Lodolo, Emanuele, Anatoly A. Schreider, and Franco Coren. "Sea-floor spreading in the easternmost Indian Ocean reveals cyclicity in ocean crust accretion (0–36 Ma)." Marine Geology 134, no. 3-4 (October 1996): 249–61. http://dx.doi.org/10.1016/0025-3227(96)00043-6.

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Boillot, G., and N. Froitzheim. "Non-volcanic rifted margins, continental break-up and the onset of sea-floor spreading: some outstanding questions." Geological Society, London, Special Publications 187, no. 1 (2001): 9–30. http://dx.doi.org/10.1144/gsl.sp.2001.187.01.02.

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Steiner, Christian, Alice Hobson, Philippe Favre, Gérard M. Stampfli, and Jean Hernandez. "Mesozoic sequence of Fuerteventura (Canary Islands): Witness of Early Jurassic sea-floor spreading in the central Atlantic." Geological Society of America Bulletin 110, no. 10 (October 1998): 1304–17. http://dx.doi.org/10.1130/0016-7606(1998)110<1304:msofci>2.3.co;2.

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Mauffret, A., D. Mougenot, P. R. Miles, and J. A. Malod. "Cenozoic deformation and Mesozoic abandoned spreading centre in the Tagus Abyssal Plain (west of Portugal): results of a multichannel seismic survey." Canadian Journal of Earth Sciences 26, no. 6 (June 1, 1989): 1101–23. http://dx.doi.org/10.1139/e89-095.

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The seismic stratigraphy of the sedimentary section that fills in the Tagus Abyssal Plain is specified by means of new multichannel seismic data. Six sedimentary sequence units are identified. These, ranging from Late Jurassic to Recent, have been dated by extrapolation of Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) drilling results and from sampling by dredging and submersible surveys. Based on this stratigraphic calibration and other geophysical data, a geodynamic evolution can be established for the Tagus Abyssal Plain. Faulting and folding in these sedimentary units clearly indicate that both the Portuguese Margin and the adjacent oceanic crust were deformed by a Miocene compressive event. An Oxfordian–Kimmeridgian rifting in the Lusitanian Basin and on the Portuguese Margin may herald a sea-floor spreading in the Tagus Abyssal Plain. The continent–ocean boundary is marked by landward-dipping reflectors similar to those observed along the Canadian margin. The oceanic structure of the Tagus Abyssal Plain is compared with those of the small oceans and (or) slow-spreading-rate centres. The eastern Tagus Abyssal Plain could be underlain by a Latest Jurassic (M-21)–Earliest Cretaceous (M16) spreading centre that was abandoned in Earliest Cretaceous (142 Ma), whereas the western Tagus Abyssal Plain could be underlain by a younger crust (from M10 to J) formed after a ridge jump. This younger oceanic domain may have a western complement in the Newfoundland Basin.

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Schaltegger, Urs, Laurent Desmurs, Gianreto Manatschal, Othmar Muntener, Martin Meier, Martin Frank, and Daniel Bernoulli. "The transition from rifting to sea-floor spreading within a magma-poor rifted margin: field and isotopic constraints." Terra Nova 14, no. 3 (June 2002): 156–62. http://dx.doi.org/10.1046/j.1365-3121.2002.00406.x.

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Al-Ahmadi, Khalid, Abdullah Al-Amri, and Linda See. "A spatial statistical analysis of the occurrence of earthquakes along the Red Sea floor spreading: clusters of seismicity." Arabian Journal of Geosciences 7, no. 7 (June 4, 2013): 2893–904. http://dx.doi.org/10.1007/s12517-013-0974-6.

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50

Wilson, Robert W., Knud Erik S. Klint, Jeroen A. M. Van Gool, Kenneth J. W. McCaffrey, Robert E. Holdsworth, and James A. Chalmers. "Faults and fractures in central West Greenland: onshore expression of continental break-up and sea-floor spreading in the Labrador – Baffin Bay Sea." Geological Survey of Denmark and Greenland (GEUS) Bulletin 11 (December 5, 2006): 185–204. http://dx.doi.org/10.34194/geusb.v11.4931.

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The complex Ungava fault zone lies in the Davis Strait and separates failed spreading centres in the Labrador Sea and Baffin Bay. This study focuses on coastal exposures east of the fault-bound Sisimiut basin, where the onshore expressions of these fault systems and the influence of pre-existing basement are examined. Regional lineament studies identify five main systems: N–S, NNE–SSW, ENE–WSW, ESE–WNW and NNW–SSE. Field studies reveal that strike-slip movements predominate, and are consistent with a ~NNE–SSW-oriented sinistral wrench system. Extensional faults trending N–S and ENE–WSW (basement-parallel), and compressional faults trending E–W, were also identified. The relative ages of these fault systems have been interpreted using cross-cutting relationships and by correlation with previously identified structures. A two-phase model for fault development fits the development of both the onshore fault systems observed in this study and regional tectonic structures offshore. The conclusions from this study show that the fault patterns and sense of movement on faults onshore reflect the stress fields that govern the opening of the Labrador Sea – Davis Strait – Baffin Bay seaway, and that the wrench couple on the Ungava transform system played a dominant role in the development of the onshore fault patterns.

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Journal articles on the topic 'Sea-floor spreading'

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