scholarly journals A long source area of the 1906 Colombia–Ecuador earthquake estimated from observed tsunami waveforms

2017 ◽  
Vol 69 (1) ◽  
Author(s):  
Yusuke Yamanaka ◽  
Yuichiro Tanioka ◽  
Takahiro Shiina
Keyword(s):  
Source Area ◽  
Tsunami Waveforms

Reexamination of Tsunami Source Models For the 20th Century Earthquakes Off Hokkaido and Tohoku Along the Eastern Margin of the Sea of Japan

2021 ◽  
Author(s):  
Satoko Murotani ◽  
Kenji Satake ◽  
Takeo Ishibe ◽  
Tomoya Harada
Keyword(s):  
20Th Century ◽  
Sea Of Japan ◽  
Near Field ◽  
Active Faults ◽  
Source Area ◽  
Tsunami Source ◽  
The Sea Of Japan ◽  
Scaling Relation ◽  
Multiple Faults ◽  
Tsunami Waveforms

Abstract Large earthquakes around Japan occur not only in the Pacific Ocean but also in the Sea of Japan, and cause both damage from the earthquake itself and from the ensuing tsunami to the coastal areas. Recently, offshore active fault surveys were conducted in the Sea of Japan by the Integrated Research Project on Seismic and Tsunami Hazards around the Sea of Japan (JSPJ), and their fault models (length, width, strike, dip, and slip angles) have been obtained. We examined the causative faults of M7 or larger earthquakes in the Sea of Japan during the 20th century using seismic and tsunami data. The 1940 off Shakotan Peninsula earthquake (MJMA 7.5) appears to have been caused by the offshore active faults MS01, MS02, ST01, and ST02 as modelled by the JSPJ. The 1993 off the southwest coast of Hokkaido earthquake (MJMA 7.8) likely occurred on the offshore active faults OK03a, OK03b, and OK05, while the 1983 Central Sea of Japan earthquake (MJMA 7.7) probably related to MMS01, MMS04, and MGM01. For these earthquakes, the observed tsunami waveforms were basically reproduced by tsunami numerical simulation from the offshore active faults with the slip amounts obtained by the scaling relation with three stages between seismic moment and source area for inland earthquakes. However, the observed tsunami runup heights along the coast were not reproduced at certain locations, possibly because of the coarse bathymetry data used for the simulation. The 1983 west off Aomori (MJMA 7.1) and the 1964 off Oga Peninsula (MJMA 6.9) earthquakes showed multiple faults near the source area that could be used to reproduce the observed tsunami waveforms; therefore, we could not identify the causative faults. Further analysis using near-field seismic waveforms is required for their identification of their causative faults and their parameters. The scaling relation for inland earthquakes can be used to obtain the slip amounts for offshore active faults in the Sea of Japan and to estimate the coastal tsunami heights and inundation area which can be useful for disaster prevention and mitigation of future earthquakes and tsunamis in the Sea of Japan.

Permo-Carboniferous sediments at Kraskov (borehole KS-1) and their source area

2015 ◽  
Author(s):  
Marcela Stárková ◽  
Štěpánka Mrázová ◽  
Tamara Sidorinová
Keyword(s):  
Source Area

The Distribution of Volatile Organics in a Leachate Plume, Gloucester, Ontario

1987 ◽  
Vol 22 (1) ◽  
pp. 49-64 ◽  
Author(s):  
J.F. Devlin ◽  
W.A. Gorman
Keyword(s):  
Organic Contaminants ◽  
Source Area ◽  
Unconfined Aquifer ◽  
High Concentration ◽  
Organic Contamination ◽  
Aquifer System ◽  
Aquifer Systems ◽  
Volatile Organic ◽  
Volatile Organic Contaminants ◽  
Aquifer Sediments

Abstract The Gloucester Landfill is located near Ottawa, Ontario, on a northeast trending ridge of Quaternary age. The ridge comprises outwash sediments which make up two aquifer systems. A confined system exists next to bedrock, and is overlain by a silty-clayey stratum (the confining layer) which is, in turn, overlain by an unconfined aquifer system. Two independent volatile organic plumes have previously been identified at the landfill: the southeast plume, which has penetrated the confined aquifer system, and the northeast plume which is migrating in the unconfined aquifer. The distribution of volatile organic contaminants at the northeast plume site appears to be a function of two factors: (1) heterogeneities in the aquifer sediments are causing the channeling of contaminants through a narrow path; (2) the low fraction of organic carbon in the unconfined aquifer sediments at the northeast site is resulting in little retardation of the contaminants there, relative to those at the southeast site. Acetate was the only volatile fatty acid detected in the leachate. It was measurable only in areas where the volatile organic contamination was significant. Although methane was detected in the contaminated sediments, suggesting that microbial activity was present, the high concentration of acetate (>1000 ppm) which was detected down-gradient from the source area indicates that any biodegradation which is occurring is proceeding at a very slow rate.

scholarly journals Correction of Eddy Covariance Based Crop ET Considering the Heat Flux Source Area

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 281
Author(s):  
Stuart L. Joy ◽  
José L. Chávez
Keyword(s):  
Heat Flux ◽  
Eddy Covariance ◽  
Agricultural Land ◽  
Flux Measurement ◽  
Source Area ◽  
Mean Bias Error ◽  
Bias Error ◽  
Crop Water ◽  
The Past ◽  
Measurement Results

Eddy covariance (EC) systems are being used to measure sensible heat (H) and latent heat (LE) fluxes in order to determine crop water use or evapotranspiration (ET). The reliability of EC measurements depends on meeting certain meteorological assumptions; the most important of such are horizontal homogeneity, stationarity, and non-advective conditions. Over heterogeneous surfaces, the spatial context of the measurement must be known in order to properly interpret the magnitude of the heat flux measurement results. Over the past decades, there has been a proliferation of ‘heat flux source area’ (i.e., footprint) modeling studies, but only a few have explored the accuracy of the models over heterogeneous agricultural land. A composite ET estimate was created by using the estimated footprint weights for an EC system in the upwind corner of four fields and separate ET estimates from each of these fields. Three analytical footprint models were evaluated by comparing the composite ET to the measured ET. All three models performed consistently well, with an average mean bias error (MBE) of about −0.03 mm h−1 (−4.4%) and root mean square error (RMSE) of 0.09 mm h−1 (10.9%). The same three footprint models were then used to adjust the EC-measured ET to account for the fraction of the footprint that extended beyond the field of interest. The effectiveness of the footprint adjustment was determined by comparing the adjusted ET estimates with the lysimetric ET measurements from within the same field. This correction decreased the absolute hourly ET MBE by 8%, and the RMSE by 1%.

CERAMIC SEQUENCE, CHRONOLOGY, AND CULTURAL DYNAMICS OF THE UCAREO-ZINAPÉCUARO, MICHOACÁN OBSIDIAN SOURCE AREA

2021 ◽  
pp. 1-21
Author(s):  
Dan M. Healan ◽  
Christine Hernández
Keyword(s):  
Source Area ◽  
Central Mexico ◽  
Cultural Dynamics ◽  
Postclassic Period ◽  
Radiocarbon Dates ◽  
Pottery Analysis ◽  
Ceramic Chronology ◽  
Cross Dating ◽  
Obsidian Source

Abstract This article presents the ceramic sequence and chronology resulting from a multi-year program of survey, excavation, and analysis of pre-Hispanic settlement and exploitation within the Zinapécuaro-Ucareo (“U-Z”), Michoacan obsidian source area. Pottery analysis and classification aided by seriation analysis identified nine ceramic complexes and seven ceramic phases and sub-phases that both expand and refine the ceramic sequence previously established for the region by Gorenstein's (1985) investigations at nearby Acámbaro, Guanajuato. Initially established by ceramic cross-dating, the U-Z ceramic chronology has been largely confirmed by 30 radiocarbon dates and spans over 2,000 years of pre-Hispanic settlement, which included at least two notable episodes of trait-unit and site-unit intrusion from the eastern El Bajío and central Mexico. One of these episodes involved the appearance of two enclaves settled by individuals from the Acambay valley c. 90 km to the East, most likely from the site of Huamango, which our data indicate would have been occupied during the Middle Postclassic period.

scholarly journals Rutile Mineral Chemistry and Zr-in-Rutile Thermometry in Provenance Study of Albian (Uppermost Lower Cretaceous) Terrigenous Quartz Sands and Sandstones in Southern Extra-Carpathian Poland

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 553
Author(s):  
Jakub Kotowski ◽  
Krzysztof Nejbert ◽  
Danuta Olszewska-Nejbert
Keyword(s):  
High Temperature ◽  
Source Area ◽  
Bimodal Distribution ◽  
Provenance Study ◽  
Eastern Group ◽  
Western Group ◽  
Quartz Sands ◽  
Probable Source ◽  
Eclogite Facies ◽  
Zr In Rutile

The geochemistry of detrital rutile grains, which are extremely resistant to weathering, was used in a provenance study of the transgressive Albian quartz sands in the southern part of extra-Carpathian Poland. Rutile grains were sampled from eight outcrops and four boreholes located on the Miechów, Szydłowiec, and Puławy Segments. The crystallization temperatures of the rutile grains, calculated using a Zr-in-rutile geothermometer, allowed for the division of the study area into three parts: western, central, and eastern. The western group of samples, located in the Miechów Segment, is characterized by a polymodal distribution of rutile crystallization temperatures (700–800 °C; 550–600 °C, and c. 900 °C) with a significant predominance of high-temperature forms, and with a clear prevalence of metapelitic over metamafic rutile. The eastern group of samples, corresponding to the Lublin Area, is monomodal and their crystallization temperatures peak at 550–600 °C. The contents of metapelitic to metamafic rutile in the study area are comparable. The central group of rutile samples with bimodal distribution (550–600 °C and 850–950 °C) most likely represents a mixing zone, with a visible influence from the western and, to a lesser extent, the eastern group. The most probable source area for the western and the central groups seems to be granulite and high-temperature eclogite facies rocks from the Bohemian Massif. The most probable source area for the eastern group of rutiles seems to be amphibolites and low temperature eclogite facies rocks, probably derived from the southern part of the Baltic Shield.

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