Episodic Emergence in the Past 3000 Years at the Akkeshi Estuary, Hokkaido, Northern Japan

2001 ◽  
Vol 56 (2) ◽  
pp. 231-241 ◽  
Author(s):  
Yuki Sawai
Keyword(s):  
Volcanic Ash ◽  
Late Quaternary ◽  
Vertical Crustal Movement ◽  
The Past ◽  
Marine Terraces ◽  
The Pacific ◽  
Tectonically Active ◽  
Emergence Event ◽  
Rapid Emergence ◽  
Northern Japan

AbstractAt the Akkeshi estuary, rapid emergence interrupted Holocene submergence at least four times in the past 3000 years. Each emergence event produced an upward change from estuarine mud to freshwater peat. While the estuarine mud abounds in brackish and marine diatoms, freshwater taxa dominate the peat. Emergence events occurred from 1700 to 2300, 1000 to 1300, and 500 to 700 cal yr B.P. An additional emergence event predated by several decades a volcanic ash that erupted in A.D. 1694. At least three of the events produced contacts abrupt enough to represent uplift during earthquakes. Such uplift may reconcile seemingly conflicting records of vertical crustal movement in eastern Hokkaido. This tectonically active area, which is being subducted by the Pacific plate at 8 cm/yr, contains marine terraces that imply 0.1–0.5 mm/yr of net uplift in the late Quaternary. However, these terraces adjoin tide gages that recorded 8–9 mm/yr of steady submergence in the 20th century. The terrace uplift need not conflict with the gaged submergence if the region is subject to occasional coseismic uplift, as during the emergence events implied by Holocene geology near Akkeshi.

scholarly journals Dating and morphostratigraphy of uplifted marine terraces in the Makran subduction zone (Iran)

2018 ◽  
Author(s):  
Raphaël Normand ◽  
Guy Simpson ◽  
Frédéric Herman ◽  
Rabiul Haque Biswas ◽  
Abbas Bahroudi ◽  
...  
Keyword(s):  
Subduction Zone ◽  
Surface Deformation ◽  
Late Quaternary ◽  
Makran Subduction Zone ◽  
Megathrust Earthquakes ◽  
Surface Uplift ◽  
Marine Terraces ◽  
Uplift Rates ◽  
Tectonically Active ◽  
East West

Abstract. The western part of the Makran subduction zone (Iran) has not experienced a great megathrust earthquake in recent human history, yet, the presence of emerged marine terraces along the coast indicates that the margin has been tectonically active during at least the late Quaternary. To better understand the surface deformation of this region, we mapped the terraces sequences of seven localities along the Iranian Makran. Additionnaly, we performed radiocarbon, 230Th/U and optically stimulated luminescence (OSL) dating of the layers of marine sediments deposited on top of the terraces. This enabled us to correlate the terraces regionally and to assign them to different Quaternary sea level highstands. Our results show east-west variations in surface uplift rates mostly between 0.05 and 1.2 mm y−1. We detected a region of anomalously high uplift rate, where two MIS 3 terraces are emerged, yet we are uncertain how to insert these results in a geologically coherent context. Although it is presently not clear whether the uplift of the terraces is linked with the occurrence of large megathrust earthquakes, our results highlight heterogeneous accumulation of deformation in the overriding plate.

Implications of Radiolarian Assemblages for the Late Quaternary Paleoceanography of the Eastern Equatorial Pacific

1985 ◽  
Vol 24 (2) ◽  
pp. 204-218 ◽  
Author(s):  
Cynthia T. Schramm
Keyword(s):  
Surface Water ◽  
Late Quaternary ◽  
Zonal Flow ◽  
Equatorial Pacific ◽  
Equatorial Undercurrent ◽  
Ice Volume ◽  
The Past ◽  
Eastern Equatorial Pacific ◽  
The Pacific ◽  
Radiolarian Assemblages

The distribution of radiolarian assemblages identified by Q-mode factor analysis of radiolarian microfossils in surface sediments from low latitudes in the Pacific Ocean reflects their associations with surface water masses. Downcore fluctuations of these radiolarian assemblages at two sites, RC10-65 and V19–29, indicate changes in circulation in the eastern equatorial Pacific during the past 500,000 yr. Surface-water radiolarian assemblages characteristic of zonal flow have dominated siliceous sedimentation in the eastern equatorial Pacific, except during times of intense upwelling which can occur along the coast of Peru and in the Equatorial Undercurrent. Fluctuations in the importance of this upwelling have not been consistent with glacial/interglacial changes in ice volume throughout the late Quaternary. Intensification of upwelling in the equatorial divergence, however, has consistently coincided with increases in ice volume in the past 500,000 yr. The times at which changes in the nature of the relationship between upwelling and ice volume occur (approximately 240,000 and 380,000 yr B.P.) roughly coincide with times of observed changes in other proxy indicators of oceanographic conditions in the Pacific and Indian oceans.

Development of a Late Quaternary Marine Terraced Landscape during On-Going Tectonic Contraction, Crescent City Coastal Plain, California

1999 ◽  
Vol 52 (2) ◽  
pp. 217-228 ◽  
Author(s):  
Michael Polenz ◽  
Harvey M. Kelsey
Keyword(s):  
Coastal Plain ◽  
Late Quaternary ◽  
Hanging Wall ◽  
Thrust Fault ◽  
Cascadia Subduction Zone ◽  
Marine Terrace ◽  
Crescent City ◽  
The North ◽  
Marine Terraces ◽  
Tectonically Active

The Crescent City coastal plain is a low-lying surface of negligible relief that lies on the upper plate of the Cascadia subduction zone in northernmost California. Whereas coastal reaches to the north in southern Oregon and to the south near Cape Mendocino contain flights of deformed marine terraces from which a neotectonic history can be deduced, equivalent terraces on the Crescent City coastal plain are not as pronounced. Reexamination of the coastal plain revealed three late Pleistocene marine terraces, identified on the basis of subtle geomorphic boundaries and further delineated by differentiable degrees of soil development. The youngest marine terrace is preserved in the axial valley of a broad syncline, and the two older marine terraces face each other across the axial region. An active thrust fault, previously recognized offshore, underlies the coastal plain, and folding in the hanging wall of this thrust fault has dictated, through differential uplift, the depositional limits of each successive marine terrace unit. This study demonstrates the importance of local structures in coastal landscape evolution along tectonically active coastlines and exemplifies the utility of soil relative-age determinations to identify actively growing folds in landscapes of low relief.

Soil Development, Relative Dating, and Correlation of Late Quaternary Marine Terraces in Southwestern Oregon

1992 ◽  
Vol 37 (1) ◽  
pp. 60-74 ◽  
Author(s):  
James G. Bockheim ◽  
Harvey M. Kelsey ◽  
James G. Marshall
Keyword(s):  
Pacific Coast ◽  
Late Quaternary ◽  
Soil Development ◽  
Morphological Properties ◽  
Relative Dating ◽  
Clayey Material ◽  
Marine Terraces ◽  
The Pacific ◽  
Coastal Terrace ◽  
Age Estimates

AbstractFlights of tectonically uplifted, late Quaternary marine terraces are preserved at several localities along the Oregon coast. Intervening coastal areas without marine terraces reflect net subsidence. These gaps in the coastal terrace record make it difficult to correlate terraces along the Pacific coast. To test the utility of soils in relative dating and correlation, two flights of marine terraces near Cape Blanco and Cape Arago were investigated. The terraces could be distinguished in each area from soil morphological properties and a quantitative index of soil development derived from field descriptions. The soils in the two areas show a progression in development from spodosols to spodosols underlain by clayey material to ultisols. The lowest two terraces at Cape Blanco, which have reported age estimates of 80,000 and 105,000 yr, are correlative with the lowest two terraces at Cape Arago. The fifth and oldest terrace at Cape Blanco has no equivalent at Cape Arago. Soil development indices for the third and fourth terraces at each area allow two alternative sets of correlations.

scholarly journals QUATERNARY CALCARENITE ("POROS") OF MYKONOS, DELOS AND RHENIA, CYCLADES ISLANDS, GREECE

2018 ◽  
Vol 36 (2) ◽  
pp. 725
Author(s):  
M. Varti-Mataranga ◽  
D. W.J. Piper
Keyword(s):  
Debris Flow ◽  
Sea Level ◽  
Thin Section ◽  
Vadose Zone ◽  
Late Quaternary ◽  
Sea Spray ◽  
The Past ◽  
Marine Terraces

Outcrops of friable calc-arenite of late Quaternary age, known as Poros rock, from Mykonos, Rhenia and Delos, are characterized sedimentologically and their cements are studied in thin section. Calcarenites of beach, coastal eolian dune, and pedogenic alluvium origin are distinguished sedimentologically. Beach calcarenite shows marine cementation by a uniform rim of micrite and bladed Mg-calcite. Some eolian dunes show precipitation of needle aragonite, probably from sea spray, but the dominant cements are sparry calcite from groundwater and vadose zone deposition of irregular micrite with meniscus and gravitational textures. Pedogenically cemented alluvium shows the characteristics of caliche, such as rhizoliths with clots and globules of micrite and circumgranular cracking. One outcrop of calcarenite from Panormos Bay in Mykonos shows beach fades at +2.5 to +4.0 m above present sea level, overlying cemented debris flow deposits. This occurrence is interpreted as Tyrrhenian in age (isotopie stage 5e) and implies regional long-term subsidence of 2 cm/ka, consistent with the lack of marine terraces in the area. Archeological sites on Delos show irregular variations of sea level of about 1 m in the past 2.5 ka, probably related to movement on faults.

MONARCHS, TRAVELLERS AND EMPIRE IN THE PACIFIC'S AGE OF REVOLUTIONS

2020 ◽  
Vol 30 ◽  
pp. 77-96
Author(s):  
Sujit Sivasundaram
Keyword(s):  
Pacific Islanders ◽  
Modern World ◽  
Global History ◽  
The Past ◽  
The Pacific ◽  
Cultural Terms ◽  
The Pacific Ocean ◽  
Definition Of ◽  
The Uk ◽  
A Site

AbstractThe Pacific has often been invisible in global histories written in the UK. Yet it has consistently been a site for contemplating the past and the future, even among Britons cast on its shores. In this lecture, I reconsider a critical moment of globalisation and empire, the ‘age of revolutions’ at the end of the eighteenth century and the start of the nineteenth century, by journeying with European voyagers to the Pacific Ocean. The lecture will point to what this age meant for Pacific islanders, in social, political and cultural terms. It works with a definition of the Pacific's age of revolutions as a surge of indigeneity met by a counter-revolutionary imperialism. What was involved in undertaking a European voyage changed in this era, even as one important expedition was interrupted by news from revolutionary Europe. Yet more fundamentally vocabularies and practices of monarchy were consolidated by islanders across the Pacific. This was followed by the outworkings of counter-revolutionary imperialism through agreements of alliance and alleged cessation. Such an argument allows me, for instance, to place the 1806 wreck of the Port-au-Prince within the Pacific's age of revolutions. This was an English ship used to raid French and Spanish targets in the Pacific, but which was stripped of its guns, iron, gunpowder and carronades by Tongans. To chart the trajectory from revolution and islander agency on to violence and empire is to appreciate the unsettled paths that gave rise to our modern world. This view foregrounds people who inhabited and travelled through the earth's oceanic frontiers. It is a global history from a specific place in the oceanic south, on the opposite side of the planet to Europe.

Culture of larval spiny lobsters: a review of work done in northern Japan

1997 ◽  
Vol 48 (8) ◽  
pp. 923 ◽  
Author(s):  
Jiro Kittaka
Keyword(s):  
Water Quality ◽  
Feeding Behaviour ◽  
The Past ◽  
Cool Temperate ◽  
Spiny Lobsters ◽  
Phyllosoma Larvae ◽  
Work Done ◽  
Plankton Feeders ◽  
Palinurus Elephas ◽  
Northern Japan

The method developed over the past decade in northern Japan to culture phyllosoma larvae of five species of principally cool-temperate spiny lobsters combines the features of upwelling water, co- cultured microalgae, and use of mussel gonad as food. The feeding behaviour of the phyllosomas shows that they are primarily predators with the pereiopods and secondarily plankton feeders with the maxillipeds and maxillae. Recent work has shown that contamination of culture water by microorganisms such as the fouling protozoans Vorticellaspp. can greatly reduce phyllosoma survival. The significance of co-cultures of microalgae in maintaining water quality is not yet fully understood. Newly hatched lavae of sailfin sandfish (Arctoscopus japonicus) is an excellent food for late-stage phyllosomas of Jasus verreauxi. About 5% of J. verreauxi phyllosomas metamorphosed into pueruli. Mortality during the puerulus stage was reduced by increasing the capacity of the culture tanks from 30 L to 100 L. A single Palinurus elephas phyllosoma raised in co-culture with diatoms and fed mussel gonad and A. japonicus larvae metamorphosed into a puerulus in 65 days after seven moults.

Identification of Dacitic Tephra by Activation Analysis of their Primary Mineral Phenocrysts

1973 ◽  
Vol 3 (2) ◽  
pp. 307-315 ◽  
Author(s):  
M.J. Dudas ◽  
M.E. Harward ◽  
R.A. Schmitt
Keyword(s):  
Rare Earth ◽  
Activation Analysis ◽  
Pacific Northwest ◽  
Late Quaternary ◽  
Minor Element ◽  
Transition Elements ◽  
Pyroclastic Deposits ◽  
Element Abundances ◽  
The Pacific ◽  
Primary Mineral

AbstractPrimary mineral phenocrysts from eight different late Quaternary pyroclastic deposits were fractionated for neutron-activation analysis with the purpose of characterizing each of the deposits on the basis of trace and minor element compositions. In hornblende separates, contents of several rare earth and transition elements were found to be distinctive for the Mazama, Glacier Peak, and several St. Helens deposits. In magnetites, abundances of transition elements are characteristic and serve as good discriminants for the pyroclastic deposits examined in this investigation. Contents of transition and rare earth elements in hyperthenes also appear useful in distinguishing volcanic ash deposits. Trace and minor element abundances in plagioclase phenocrysts did not appear adequate for identification of pyroclastics due to elemental depletion and similarity of contents for feldspar separates. It was found that contents of Sm and Yb in hornblende phenocrysts would serve to distinguish between several pyroclastic deposits from the Pacific Northwest.

scholarly journals Global nutrient transport in a world of giants

2015 ◽  
Vol 113 (4) ◽  
pp. 868-873 ◽  
Author(s):  
Christopher E. Doughty ◽  
Joe Roman ◽  
Søren Faurby ◽  
Adam Wolf ◽  
Alifa Haque ◽  
...  
Keyword(s):  
Surface Waters ◽  
Marine Mammals ◽  
Recent Literature ◽  
Late Quaternary ◽  
Nutrient Transport ◽  
Anadromous Fish ◽  
Upward Movement ◽  
The Past ◽  
Large Animals ◽  
Continental Interior

The past was a world of giants, with abundant whales in the sea and large animals roaming the land. However, that world came to an end following massive late-Quaternary megafauna extinctions on land and widespread population reductions in great whale populations over the past few centuries. These losses are likely to have had important consequences for broad-scale nutrient cycling, because recent literature suggests that large animals disproportionately drive nutrient movement. We estimate that the capacity of animals to move nutrients away from concentration patches has decreased to about 8% of the preextinction value on land and about 5% of historic values in oceans. For phosphorus (P), a key nutrient, upward movement in the ocean by marine mammals is about 23% of its former capacity (previously about 340 million kg of P per year). Movements by seabirds and anadromous fish provide important transfer of nutrients from the sea to land, totalling ∼150 million kg of P per year globally in the past, a transfer that has declined to less than 4% of this value as a result of the decimation of seabird colonies and anadromous fish populations. We propose that in the past, marine mammals, seabirds, anadromous fish, and terrestrial animals likely formed an interlinked system recycling nutrients from the ocean depths to the continental interiors, with marine mammals moving nutrients from the deep sea to surface waters, seabirds and anadromous fish moving nutrients from the ocean to land, and large animals moving nutrients away from hotspots into the continental interior.

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