scholarly journals Paleotsunamis on the Southern Hikurangi Subduction Zone, New Zealand, Show Regular Recurrence of Large Subduction Earthquakes

2021 ◽  
Vol 1 (2) ◽  
pp. 75-84
Author(s):  
Charlotte Pizer ◽  
Kate Clark ◽  
Jamie Howarth ◽  
Ed Garrett ◽  
Xiaoming Wang ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Subduction Zone ◽  
Recurrence Interval ◽  
Fault System ◽  
Plate Boundaries ◽  
The Past ◽  
Subduction Earthquakes ◽  
Tsunami Hazard Assessment ◽  
First Time ◽  
Large Earthquakes

Abstract Geological records of subduction earthquakes, essential for seismic and tsunami hazard assessment, are difficult to obtain at transitional plate boundaries, because upper-plate fault earthquake deformation can mask the subduction zone signal. Here, we examine unusual shell layers within a paleolagoon at Lake Grassmere, at the transition zone between the Hikurangi subduction zone and the Marlborough fault system. Based on biostratigraphic and sedimentological analyses, we interpret the shell layers as tsunami deposits. These are dated at 2145–1837 and 1505–1283 yr B.P., and the most likely source of these tsunamis was ruptures of the southern Hikurangi subduction interface. Identification of these two large earthquakes brings the total record of southern Hikurangi subduction earthquakes to four in the past 2000 yr. For the first time, it is possible to obtain a geologically constrained recurrence interval for the southern Hikurangi subduction zone. We calculate a recurrence interval of 500 yr (335–655 yr, 95% confidence interval) and a coefficient of variation of 0.27 (0.0–0.47, 95% confidence interval). The probability of a large subduction earthquake on the southern Hikurangi subduction zone is 26% within the next 50 yr. We find no consistent temporal relationship between subduction earthquakes and large earthquakes on upper-plate faults.

scholarly journals Volcanic eruptions are triggered in static dilatational strain fields generated by large earthquakes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takeshi Nishimura
Keyword(s):  
Volcanic Eruptions ◽  
Large Earthquake ◽  
Strain Fields ◽  
Buoyant Force ◽  
The Past ◽  
Volcanic Data ◽  
Magma System ◽  
First Time ◽  
Large Earthquakes ◽  
Strong Ground

AbstractAlthough data catalog analyses have confirmed that volcanic eruptions are triggered by large earthquakes, the triggering mechanism has been under discussion for many decades. In the present study, recent earthquake and volcanic data from the past 35–55 years were analyzed, and it was demonstrated for the first time that the likelihood of new eruptions increases two to three times in the 5–10 years following large earthquakes for volcanoes where the generated static dilatational strain exceeds 0.5 µ, which may, for example, activate gas bubble growth and thereby generate a buoyant force in the magma. In contrast, the eruption likelihood does not increase for volcanoes that are subjected to strong ground motion alone, which affect the magma system and volcanic edifice. These results indicate that we can evaluate the likelihood of triggered eruptions and prepare for new eruptions when a large earthquake occurs.

scholarly journals IODP Expedition 319, NanTroSEIZE Stage 2: First IODP Riser Drilling Operations and Observatory Installation Towards Understanding Subduction Zone Seismogenesis

2010 ◽  
Vol 10 ◽  
pp. 4-13 ◽  
Author(s):  
L. McNeill ◽  
D. Saffer ◽  
T. Byrne ◽  
E. Araki ◽  
S. Toczko ◽  
...  
Keyword(s):  
Subduction Zone ◽  
Fault Zone ◽  
Hanging Wall ◽  
Plate Boundary ◽  
Fault System ◽  
Seismogenic Zone ◽  
Plate Boundaries ◽  
Forearc Basin ◽  
Drilling Operations

The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is a major drilling project designed to investigate fault mechanics and the seismogenic behavior of subduction zone plate boundaries. Expedition 319 is the first riser drilling operation within scientific ocean drilling. Operations included riser drilling at Site C0009 in the forearc basin above the plate boundary fault, non-riser drilling at Site C0010 across the shallow part of the megasplay fault system &ndash; which may slip during plate boundary earthquakes &ndash; and initial drilling at Site C0011 (incoming oceanic plate) for Expedition 322. At Site C0009, new methods were tested, including analysis of drill mud cuttings and gas, and <i>in situ</i> measurements of stress, pore pressure, and permeability. These results, in conjunction with earlier drilling, will provide (a) the history of forearc basin development (including links to growth of the megasplay fault system and modern prism), (b) the first <i>in situ</i> hydrological measurements of the plate boundary hanging wall, and (c) integration of <i>in situ</i> stress measurements (orientation and magnitude) across the forearc and with depth. A vertical seismic profile (VSP) experiment provides improved constraints on the deeper structure of the subduction zone. At Site C0010, logging-while-drilling measurements indicate significant changes in fault zone and hanging wall properties over short (< 5 km) along-strike distances, suggesting different burial and/or uplift history. The first borehole observatory instruments were installed at Site C0010 to monitor pressure and temperature within the megasplay fault zone, and methods of deployment of more complex observatory instruments were tested for future operations. <br><br> doi:<a href="http://dx.doi.org/10.2204/iodp.sd.10.01.2010" target="_blank">10.2204/iodp.sd.10.01.2010</a>

Identification of the Seismogenic Fault of the 1654 M 8.0 Tianshui Earthquake, Northeastern Tibetan Plateau

2021 ◽  
Author(s):  
Peng Chen ◽  
Wei Shi ◽  
Jianmin Hu ◽  
Bing Yan ◽  
Haifeng Lu
Keyword(s):  
Tibetan Plateau ◽  
Large Earthquake ◽  
Recurrence Interval ◽  
Seismogenic Fault ◽  
The Past ◽  
Northeastern Tibetan Plateau ◽  
New Evidence ◽  
Historic Earthquakes ◽  
Large Earthquakes ◽  
Morphogenic Earthquake

Abstract The 1654 M 8.0 Tianshui earthquake occurred in the triangle area bounded by the West Qinling fault (WQLF) and Lixian–Luojiabao fault (LLF) in the northeastern Tibetan plateau. Previous studies reported that the LLF is the source for this earthquake based on the historical records and the Holocene fault activities. However, topographic analyses, outcrop observations, trench excavations associated with the WQLF, together with the radiocarbon dating results reveal that (1) the most recent surface-rupturing earthquake (E1) occurred in the past 470 yr, which can only correspond to the 1654 Tianshui earthquake if the historic earthquakes record is complete. This result means that the seismogenic fault, which is responsible for the 1654 Tianshui earthquake is the WQLF, rather than the LLF as previously reported; (2) the penultimate morphogenic earthquake (E2) took place in the period of 2693–760 yr Cal B.P.; (3) the third recent large earthquake (E3) occurred in the period of 10,229–6032 yr Cal B.P. with a higher probability in this range of 9005–8596 yr Cal B.P.; and (4) in consideration of the double time span of event E3 when compared with event E2 and E1, there is a possibility that another morphogenic earthquake took place in the period of 8596–6032 yr Cal B.P., and then the fourth surface-rupturing event (E4) occurred in the period of 9005–8596 yr Cal B.P. Therefore, at least three or four Holocene slipping events have occurred upon the WQLF in the past ∼9000  yr, suggesting an average recurrence interval of large earthquakes of 2250–3000 yr. The new evidence associated with the source of the 1654 M 8.0 Tianshui earthquake and the recurrence interval of large earthquakes on the WQLF will throw light on the reassessment of seismic potential in this area.

scholarly journals Volcanism and Volcanogenic Submarine Sedimentation in the Paleogene Foreland Basins of the Alps: Reassessing the Source-to-Sink Systems with an Actualist View

Geosciences ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Andrea Di Capua ◽  
Federica Barilaro ◽  
Gianluca Groppelli
Keyword(s):  
Foreland Basin ◽  
Fault System ◽  
Foreland Basins ◽  
The North ◽  
Source To Sink ◽  
The Alps ◽  
Alpine Foreland ◽  
Alpine Foreland Basin ◽  
Tectonic Lineament ◽  
First Time

This work critically reviews the Eocene–Oligocene source-to-sink systems accumulating volcanogenic sequences in the basins around the Alps. Through the years, these volcanogenic sequences have been correlated to the plutonic bodies along the Periadriatic Fault System, the main tectonic lineament running from West to East within the axis of the belt. Starting from the large amounts of data present in literature, for the first time we present an integrated 4D model on the evolution of the sediment pathways that once connected the magmatic sources to the basins. The magmatic systems started to develop during the Eocene in the Alps, supplying detritus to the Adriatic Foredeep. The progradation of volcanogenic sequences in the Northern Alpine Foreland Basin is subsequent and probably was favoured by the migration of the magmatic systems to the North and to the West. At around 30 Ma, the Northern Apennine Foredeep also was fed by large volcanogenic inputs, but the palinspastic reconstruction of the Adriatic Foredeep, together with stratigraphic and petrographic data, allows us to safely exclude the Alps as volcanogenic sources. Beyond the regional case, this review underlines the importance of a solid stratigraphic approach in the reconstruction of the source-to-sink system evolution of any basin.

FC14-01 - Internal losses and the creation of “Nowhere land”: psychodynamic themes of adults with ADHD discovered during drama-therapy

2011 ◽  
Vol 26 (S2) ◽  
pp. 1893-1893
Author(s):  
I. Manor ◽  
G. Yazpan
Keyword(s):  
Drama Therapy ◽  
Transitional Space ◽  
Men And Women ◽  
The Past ◽  
Chronic Disorder ◽  
Pharmacological Aspect ◽  
Inner Self ◽  
Socioeconomic Strata ◽  
The Creation ◽  
First Time

ADHD is a well-known, chronic disorder that persists in adulthood. During the past 20 years its existence in adults is becoming clearer, yet its dynamic aspects are rarely discussed. The treatment of adults is vital, as much as that of children; however the literature discussing it, especially its non-pharmacological aspect, is scarce.We describe the results of our treatment with drama-therapy of two groups of adults with ADHD. These groups included 11 adults (from both groups), men and women, from most socioeconomic strata, aged ≥ 60 yrs., who were diagnosed as suffering from ADHD and were treated for it for the first time in their life. Drama-therapy was selected as we believed it to be a useful method with associative, distracted ADHD patients, since it enabled the use of transitional space through non-verbal images and acts.This presentation discusses the basic themes with which patients began therapy. Interestingly, all patients, however different, shared the same themes that were built on self doubt and the pre-presumption of disappointment. The impairment related to ADHD, that was felt, but not understood, led to a strong experience of heavy losses, which we tried to define separately: of a clear path, of control, of the inner perception of borders and of the loss of an integrative inner self. All these losses were accumulated in the transitional space in a place we named “Nowhere land”.We would like to present these themes of losses and of becoming lost and to discuss their meaning.

BRAZILIAN BISHOP OUTLINES "A PASTORAL STRATEGY IN TIMES OF REVOLUTION"

Exchange ◽  
1982 ◽  
Vol 11 (1) ◽  
pp. 48-57
Keyword(s):  
Northeast Brazil ◽  
Profound Change ◽  
Christian Communities ◽  
The Past ◽  
First Time

AbstractMons. Antonio Batista Fragoso has been bishop of Crateus in Northeast Brazil for the past ten years. Eighty percent of the 360,000 people in his diocese are impoverished peasants who engage in rudimentary farming. At least half of the peasants are landless. It is among these people that Bishop Fragoso has encouraged the formation of small grassroots Christian communities that are responsible for a profound change in the patterns of Christian living in his diocese. The following is LP's translation of excerpts from a talk that Bishop Fragoso gave to his fellow bishops and priests in Managua in October, 1980. This is the first time it has appeared in English. (Editor Latinamerica Press)

Summary of Coastal Geologic Evidence for past Great Earthquakes at the Cascadia Subduction Zone

1995 ◽  
Vol 11 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Brian F. Atwater ◽  
Alan R. Nelson ◽  
John J. Clague ◽  
Gary A. Carver ◽  
David K. Yamaguchi ◽  
...  
Keyword(s):  
British Columbia ◽  
North America ◽  
Subduction Zone ◽  
Forest Soils ◽  
Pacific Coast ◽  
Cascadia Subduction Zone ◽  
Level Change ◽  
The Past ◽  
The Pacific ◽  
Juan De Fuca

Earthquakes in the past few thousand years have left signs of land-level change, tsunamis, and shaking along the Pacific coast at the Cascadia subduction zone. Sudden lowering of land accounts for many of the buried marsh and forest soils at estuaries between southern British Columbia and northern California. Sand layers on some of these soils imply that tsunamis were triggered by some of the events that lowered the land. Liquefaction features show that inland shaking accompanied sudden coastal subsidence at the Washington-Oregon border about 300 years ago. The combined evidence for subsidence, tsunamis, and shaking shows that earthquakes of magnitude 8 or larger have occurred on the boundary between the overriding North America plate and the downgoing Juan de Fuca and Gorda plates. Intervals between the earthquakes are poorly known because of uncertainties about the number and ages of the earthquakes. Current estimates for individual intervals at specific coastal sites range from a few centuries to about one thousand years.

scholarly journals Novel AI driven approach to classify infant motor functions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Simon Reich ◽  
Dajie Zhang ◽  
Tomas Kulvicius ◽  
Sven Bölte ◽  
Karin Nielsen-Saines ◽  
...  
Keyword(s):  
Learning Algorithm ◽  
Movement Pattern ◽  
Video Stream ◽  
Typically Developing ◽  
The Past ◽  
Movement Assessment ◽  
Computer Based ◽  
Ablation Study ◽  
First Time ◽  
Efficient Screening

AbstractThe past decade has evinced a boom of computer-based approaches to aid movement assessment in early infancy. Increasing interests have been dedicated to develop AI driven approaches to complement the classic Prechtl general movements assessment (GMA). This study proposes a novel machine learning algorithm to detect an age-specific movement pattern, the fidgety movements (FMs), in a prospectively collected sample of typically developing infants. Participants were recorded using a passive, single camera RGB video stream. The dataset of 2800 five-second snippets was annotated by two well-trained and experienced GMA assessors, with excellent inter- and intra-rater reliabilities. Using OpenPose, the infant full pose was recovered from the video stream in the form of a 25-points skeleton. This skeleton was used as input vector for a shallow multilayer neural network (SMNN). An ablation study was performed to justify the network’s architecture and hyperparameters. We show for the first time that the SMNN is sufficient to discriminate fidgety from non-fidgety movements in a sample of age-specific typical movements with a classification accuracy of 88%. The computer-based solutions will complement original GMA to consistently perform accurate and efficient screening and diagnosis that may become universally accessible in daily clinical practice in the future.

New species and record of Pseudonereis (Annelida, Polychaeta, Nereididae) from Taiwan

Zootaxa ◽  
2021 ◽  
Vol 4996 (3) ◽  
pp. 492-512
Author(s):  
PAN-WEN HSUEH
Keyword(s):  
New Species ◽  
New Record ◽  
Length Ratio ◽  
Offshore Island ◽  
The Past ◽  
New Record Species ◽  
Ridge Pattern ◽  
Two New Species ◽  
First Time ◽  
Key Characters

Two new species and one new record species of the genus Pseudonereis are described from specimens collected from ecological surveys of coasts of Taiwan and an offshore island during the past 15 years: P. jihueiensis n. sp., P. kihawensis n. sp., and P. trimaculata. Epitokes of P. jihueiensis n. sp. and P. trimaculata are also described. Pseudonereis jihueiensis n. sp. can be distinguished from congeners by having edentate jaws, χ-shaped ridge pattern of Areas VI–V–VI, parapodial morphology (i.e., length ratio of dorsal cirrus to dorsal ligule or presence of small pennant-like dorsal ligule, shape of dorsal ligule in certain region of chaetigers), and no heterogomph spinigers in the subacicular fascicle of the neuropodia. Pseudonereis kihawensis n. sp. differs from congeners by having crescent-shaped pointed-bars in Area VI, λ-shaped ridge pattern of Areas VI–V–VI, parapodial morphology (i.e., length ratio of dorsal cirrus to dorsal ligule or presence of small pennant-like dorsal ligule or shape of dorsal ligule in certain region of chaetigers), and no heterogomph spinigers in the subacicular fascicle of the neuropodia. Pseudonereis trimaculata, a species originally described from Indonesia, is reported from Taiwan for the first time. A table of key characters for all species of Pseudonereis is provided.  

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