scholarly journals Three thousand year paleo-tsunami history of the southern part of the Japan Trench

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hokuto Higaki ◽  
Kazuhisa Goto ◽  
Hideaki Yanagisawa ◽  
Daisuke Sugawara ◽  
Takashi Ishizawa
Keyword(s):  
Sediment Cores ◽  
Mineralogical Composition ◽  
High Elevation ◽  
Japan Trench ◽  
Recent Event ◽  
Chiba Prefecture ◽  
Sandy Layer ◽  
History Of ◽  
Geochemical Markers ◽  
Large Earthquakes

AbstractThis study conducted a field survey and multiproxy analyses on sediment cores retrieved from the Kobatake-ike pond in Choshi City, Chiba Prefecture, Japan. Kobatake-ike pond is located at a high elevation (i.e., 11 m above present-day sea level) and faces the southern part of the Japan Trench. Three event sand layers were detected within the continuous mud and peat sequences of 3000 years. Based on the multi-proxy analyses, including mineralogical composition, diatom assemblages, and geochemical markers, these sedimentological events were associated with past tsunamis. The most recent event was a sandy layer and is attributed to the AD 1677 Enpo tsunami, which was reported by an earlier study conducted in the pond. Our results demonstrated that two older sand layers are associated with large tsunamis that struck the Choshi area in AD 896–1445 and in BC 488–AD 215. In addition, the age ranges of these events seem to overlap that of large earthquakes and tsunamis known from the central part of the Japan Trench. This implies a possible spatiotemporal relation of earthquake generations between the central and southern parts of the Japan Trench. However, since the error ranges of the ages of tsunami deposits at the southern and central parts of the Japan Trench are still large, further investigation is required to clarify the relations of large earthquakes in both areas.

scholarly journals Three thousand year paleo-tsunami history of the southern part of the Japan Trench

2020 ◽  
Author(s):  
Hokuto Higaki ◽  
Kazuhisa Goto ◽  
Hideaki Yanagisawa ◽  
Daisuke Sugawara ◽  
Takashi Ishizawa
Keyword(s):  
Sediment Cores ◽  
Mineralogical Composition ◽  
High Elevation ◽  
Japan Trench ◽  
Chiba Prefecture ◽  
Rupture Area ◽  
History Of ◽  
Geochemical Markers ◽  
Relationship Of ◽  
Large Earthquakes

Abstract This study conducted a field survey and multiproxy analyses on sediment cores retrieved from the Kobatake-ike pond in Choshi City, Chiba prefecture, Japan. Kobatake-ike pond is located at a high elevation (i.e., 11 m above present-day sea level) and faces the southern part of the Japan Trench. Three sedimentological events were detected within the continuous mud and peat sequences of three thousand years. Based on the multi-proxy analyses, including mineralogical composition, diatom assemblages, and geochemical markers, these sedimentological events were associated with past tsunamis. The most recent event was a sandy layer from the AD 1677 Enpo tsunami, reported by an earlier study conducted in the pond. The estimated recurrence interval for tsunamis was approximately 700 years, comparable to that of the central part of the Japan Trench. The timing of at least two of three sedimentological events seems to have been close (i.e., intervals of few tens of years) before or after the occurrence of large earthquakes and tsunamis along the central part of the Japan Trench. This implies a possible spatiotemporal relation of earthquake generations between the central and southern parts of the Japan Trench, which can be associated with drastic changes in stress fields in the neighborhood of the rupture area. The risk of future large earthquakes and tsunamis along the southern part of the Japan Trench seems exceptionally high, considering the stress change caused by Tohoku-oki earthquake with 9.0 Mw in 2011. This study necessitates the need to investigate the spatiotemporal relationship of large earthquakes from the perspectives of geology, seismology, and history.

scholarly journals Three Thousand Year Paleotsunami History of Southern Part of Japan Trench

2020 ◽  
Author(s):  
Hokuto Higaki ◽  
Kazuhisa Goto ◽  
Hideaki Yanagisawa ◽  
Daisuke Sugawara ◽  
Takashi Ishizawa
Keyword(s):  
Low Frequency ◽  
Large Earthquake ◽  
High Elevation ◽  
Japan Trench ◽  
Tsunami Deposit ◽  
Geological Evidence ◽  
Chiba Prefecture ◽  
Rupture Area ◽  
Grain Size Distributions ◽  
History Of

Abstract Paleotsunami studies along the southern part of Japan Trench are scarce. Additional geological evidence must be collected. This study conducted field survey and multi-proxy analysis for drilling cores taken from a pond of Choshi City, Chiba prefecture, Japan, where the 1677 Enpo tsunami deposit was reported earlier. The pond is suitable for detection of sedimentary evidence of low-frequency but large tsunamis only because it is located at a high elevation (11 m). Three event deposits are intercalated in the three thousand year long continuous mud and peat sequences. Based on multi-proxy analyses conducted of grain size distributions, diatom assemblages, and geochemical markers, these event deposits were identified as tsunami deposits; the most recent was the AD 1677 Enpo tsunami. The estimated recurrence interval of the tsunami is approximately 700 years, which is comparable to those of the central part of the Japan Trench. It is noteworthy that the timing of these tsunami events along the southern part of the Japan Trench seems to have been close (few tens of years intervals) before or after the occurrence of large earthquakes and tsunamis along the central part of the Japan Trench. Therefore, a spatial-temporal relation of earthquake and tsunami generations might exist between central and southern parts of the Japan Trench, which might be explained by drastic changes of stress fields surrounding the rupture area of a huge earthquake. Considering the current situation, by which the Mw=9.0 2011 Tohoku-oki earthquake had occurred at central part of the Japan Trench, this possibility should be investigated carefully from perspectives of seismology and history because risks of future occurrence of large earthquake and tsunami events along the southern part of Japan Trench might be extremely high.

Applications of SEM/EDXA in cement clinker investigation

1990 ◽  
Vol 48 (4) ◽  
pp. 870-871
Author(s):  
Arezki Tagnit-Hamou ◽  
Shondeep L. Sarkar
Keyword(s):  
Mineralogical Composition ◽  
Physicochemical Characteristics ◽  
Cement Clinker ◽  
Accurate Information ◽  
Phase Identification ◽  
History Of ◽  
Bulk Chemical ◽  
Resolution Imaging ◽  
Proven Method ◽  
Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

Distribution of Mercury in Lake St. Clair and the St. Clair River Sediments

1989 ◽  
Vol 24 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Alena Mudroch ◽  
K. Hill
Keyword(s):  
Organic Matter ◽  
Sediment Cores ◽  
River Sediments ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Recent Sediment ◽  
Geochemical Composition ◽  
Visual Appearance ◽  
Decaying Wood ◽  
Relationship Of

Abstract Sediment cores were collected in Lake St. Clair in 1985 and in the St. Clair River in 1986 to investigate the horizontal and vertical distribution and association of Hg in the sediments. A layer of recent sediment up to about 35 cm thick was differentiated by the geochemical composition and visual appearance from the underlying glacial-lacustrine deposits. The concentration of Hg in the surficial sediments in Lake St. Clair was lower in 1985 (<0.025 to 1.200 µg/g) than that found in 1974 (<0.20 to 3.00 µg/g). Up to 8.30 µg/g of Hg were found in the sediments collected from the nearshore area at Sarnia, Ontario, in the St. Clair River in 1986. The concentrations of Hg ranged from 5.05 to 16.00 µg/g in different sand-sized fractions (0.063 to 0.350 mm) of the sediment. The concentration of Hg was 17.80 µg/g in the silt-clay size fraction (<0.063 mm). No relationship was found between the concentration of organic matter and Hg, and the concentration of silica and Hg in the St. Clair River sediments. The results indicated a relationship of Hg with particles of different mineralogical composition. Up to 3.72 µg/g Hg was found in the surface sediment in Chenal Ecarte. The greatest concentration of Hg (13.15 µg/g) existed in the 0.350 mm particle size fraction, which consisted mainly of small pieces of decaying wood. A good relationship was found between the concentration of Hg and organic matter in the sediment at this area.

scholarly journals Holocene polynya dynamics and their interaction with oceanic heat transport in northernmost Baffin Bay

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rebecca Jackson ◽  
Anna Bang Kvorning ◽  
Audrey Limoges ◽  
Eleanor Georgiadis ◽  
Steffen M. Olsen ◽  
...  
Keyword(s):  
Sediment Cores ◽  
Active Role ◽  
Atlantic Water ◽  
The Arctic ◽  
Negative Consequences ◽  
Baffin Bay ◽  
The North ◽  
North Water ◽  
History Of ◽  
Ocean Conditions

AbstractBaffin Bay hosts the largest and most productive of the Arctic polynyas: the North Water (NOW). Despite its significance and active role in water mass formation, the history of the NOW beyond the observational era remains poorly known. We reconcile the previously unassessed relationship between long-term NOW dynamics and ocean conditions by applying a multiproxy approach to two marine sediment cores from the region that, together, span the Holocene. Declining influence of Atlantic Water in the NOW is coeval with regional records that indicate the inception of a strong and recurrent polynya from ~ 4400 yrs BP, in line with Neoglacial cooling. During warmer Holocene intervals such as the Roman Warm Period, a weaker NOW is evident, and its reduced capacity to influence bottom ocean conditions facilitated northward penetration of Atlantic Water. Future warming in the Arctic may have negative consequences for this vital biological oasis, with the potential knock-on effect of warm water penetration further north and intensified melt of the marine-terminating glaciers that flank the coast of northwest Greenland.

A millennium-long perspective on high-elevation pine recruitment in the Spanish central Pyrenees

2018 ◽  
Vol 48 (9) ◽  
pp. 1108-1113 ◽  
Author(s):  
Gabriel Sangüesa-Barreda ◽  
J. Julio Camarero ◽  
Jan Esper ◽  
J. Diego Galván ◽  
Ulf Büntgen
Keyword(s):  
Ring Width ◽  
High Elevation ◽  
Upward Migration ◽  
Scale Temperature ◽  
Decadal Scale ◽  
History Of ◽  
Climatic Drivers ◽  
Individual Trees ◽  
Central Pyrenees

Long-term fluctuations in forest recruitment, at time scales well beyond the life-span of individual trees, can be related to climate changes. The underlying climatic drivers are, however, often understudied. Here, we present the recruitment history of a high-elevation mountain pine (Pinus uncinata Ram.) forest in the Spanish central Pyrenees throughout the last millennium. A total of 1108 ring-width series translated into a continuous chronology from 924 to 2014 CE, which allowed estimated germination dates of 470 trees to be compared against decadal-scale temperature variability. High recruitment intensity mainly coincided with relatively warm periods in the early 14th, 15th, 19th, and 20th centuries, whereas cold phases during the mid-17th, early 18th, and mid-19th centuries overlapped with generally low recruitment rates. In revealing the importance of prolonged warm conditions for high-elevation pine recruitment in the Pyrenees, this study suggests increased densification and even possible upward migration of tree-line ecotones under predicted global warming.

SEM-based mineralogical mapping at the submicrometer-scale of modern Sardinian stromatolites

2021 ◽  
Author(s):  
Juliette Debrie ◽  
Dimitri Prêt ◽  
Karim Benzerara ◽  
Jean Paul Saint Martin
Keyword(s):  
Mineralogical Composition ◽  
Treatment Method ◽  
Heterogeneous Distribution ◽  
X Ray ◽  
Mineral Phases ◽  
Saint Martin ◽  
History Of ◽  
Phase Recognition ◽  
Mineral Mixtures ◽  
Insight Into

<p>Stromatolites, i.e. macroscopically laminated carbonate rocks formed by diverse microbial communities, are particularly emblematic geobiological materials since they are the oldest evidence of life-mineral interactions, dated up to 3.5 Gyrs ago.  They are found throughout the history of the Earth and have received strong attention because they provide precious information about microbial paleobiodiversity and paleoenvironments. However, while this information is interpreted based on our knowledge about modern analogs, the latter remains very incomplete. Here, we studied recently discovered modern stromatolites from Mari Ermi<sup>1</sup>, a coastal pond in Western Sardinia, that seasonally experience severe evaporation and broad salinity variations. For this purpose, we explored the mineralogical composition of these unique sedimentary archives and its spatial variations in order to gain better insight into how mineral phases record the conditions and processes of their formation. We investigated the heterogeneous distribution of minerals using quantitative X-ray chemical maps provided by energy dispersive x-ray spectrometry analyses coupled with scanning electron microscopy (SEM-EDXS). Hyperspectral maps were analyzed using an innovative data treatment method <sup>2</sup> allowing phase recognition within the complex mineral mixtures and solid solutions encountered. This method provided quantitative data on spatial distribution, modal content and associated calculated unit formulas for each identified mineral and phase with a hundred nanometer resolution. Based on these results, we will discuss the origin of the laminations in the stromatolites.</p><p>Reference:</p><p>1. Saint Martin, J.-P. & Saint Martin, S. Geo-Eco-Marina <strong>21</strong>, 35–53 (2015a).</p><p>2. Prêt, D. et al. American Mineralogist <strong>95</strong>, 1379–1388 (2010).</p>

The History of Human Impacts in the Clear Lake Watershed ( California) as Deduced from Lake Sediment Cores*

1999 ◽  
Author(s):  
Douglas Nelson ◽  
Alan Heyvaert ◽  
Laurent Meillier ◽  
Jae Kim ◽  
Xiaoping Li ◽  
...  
Keyword(s):  
Lake Sediment ◽  
Human Impacts ◽  
Sediment Cores ◽  
Clear Lake ◽  
History Of

scholarly journals WHAT THE BRICKS TELL US FROM A TEMPLE AT BURKHAN KHALDUN MOUNTAINS: CHRONOLOGICAL INSIGHTS FROM pIRIR LUMINESCENCE

2017 ◽  
pp. 4-12
Author(s):  
Saran S ◽  
Tengis S ◽  
Tsogtbaatar B
Keyword(s):  
Mineralogical Composition ◽  
World Heritage Site ◽  
Sacred Landscape ◽  
Great Opportunity ◽  
Fine Grain ◽  
Infrared Luminescence ◽  
Heritage Site ◽  
Unesco World Heritage Site ◽  
Time Period ◽  
History Of

The Burkhan Khaldun Mountains (Mongolia) and its surrounding sacred landscape are associated with Genghis Khan’s birth and burial place as described in “The Secret History of the Mongols”. It was listed as a UNESCO World Heritage Site on 4 July 2015 under the title «Great Burkhan Khaldun Mountain and its surrounding sacred landscape.”This study offered a great opportunity to apply the recently developed post-IR infrared luminescence (pIRIR) approach to feldspar using coarse and polymineral fine grain techniques and determine the manufacturing date of a brick sample associated with the ruins of the Buddhist temple at the Burkhan Khaldun Mountains. Furthermore, the mineralogical composition of different blue-grey colored bricks from various temple buildings such as the Buddhist temples in Karakorum, Dugan in Erdene Zuu and Avargyn Balgas were studied. The original place and date of manufacturing of the bricks was revealed using the pIRIR180 and pIRIR240 from coarse and fine grains from a heated feldspar sample and were 1280±40 AD and 1230±50 AD, correspondingly, which falls into the time period of extensive constructions in Karakorum.

Penguin occupation in the Vestfold Hills

2008 ◽  
Vol 21 (2) ◽  
pp. 131-134 ◽  
Author(s):  
Tao Huang ◽  
Liguang Sun ◽  
Yuhong Wang ◽  
Renbin Zhu
Keyword(s):  
Sediment Core ◽  
Environmental Changes ◽  
Sediment Cores ◽  
East Antarctica ◽  
Before Present ◽  
The Holocene ◽  
History Of ◽  
Vestfold Hills ◽  
Free Area ◽  
Ornithogenic Sediment

AbstractDuring CHINARE-22 (December 2005–March 2006), we investigated six penguin colonies in the Vestfold Hills, East Antarctica, and collected several penguin ornithogenic sediment cores, samples of fresh guano and modern penguin bone and feather. We selected seven penguin bones and feathers and six sediments from the longest sediment core and performed AMS14C dating. The results indicate that penguins occupied the Vestfold Hills as early as 8500 calibrated years before present (cal. yrbp), following local deglaciation and the formation of the ice free area. This is the first report on the Holocene history of penguins in the Vestfold Hills. As in other areas of Antarctica, penguins occupied this area as soon as local ice retreated and the ice free area formed, and they are very sensitive to climatic and environmental changes. This work provides the foundation for understanding the history of penguins occupation in Vestfold Hills, East Antarctica.

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