scholarly journals THE HINDU KUSH EARTHQUAKE on October 26, 2015 with Mw=7.5, I0~7: PRELIMINARY SEISMICITY and AFTERSHOCK SEQUENCE

2021 ◽  
pp. 324-339
Author(s):  
R. Mikhailova ◽  
T. Ulubieva ◽  
N. Petrova
Keyword(s):  
United Arab Emirates ◽  
Aftershock Sequence ◽  
Joint Analysis ◽  
Nodal Plane ◽  
Strong Earthquakes ◽  
Absolute Value ◽  
Average Value ◽  
The North ◽  
Omori Law ◽  
Hindu Kush

On October 26, 2015, a strong Hindu Kush earthquake with KR=17.0, Mw=7.5 occurred in the Afghan Pamir-Hindu Kush subzone at a depth of hpP=217 km. Shakes of varying intensity caused by this earthquake were recorded in settlements of 14 states: Afghanistan, Tajikistan, Pakistan, Turkmenistan, India, Kyrgyzstan, Uzbekistan, Kazakhstan, China, Iran, Nepal, United Arab Emirates, Russia, Qatar and Bangladesh with a total area of S=14106 km2. The earthquake was preceded by three large (KR=12.5, 12.1, 14.0) foreshocks and was accompanied by a series of more than 1400 aftershocks unprecedented for aftershocks of deep earthquakes with KR=9–13. The energy step between the mainshock and the maximum foreshock is Kfor=3.0, between the mainshock and the maximum (KR=12.8) aftershock – Kaft=4.2. The aftershock recurrence graph has a slope =–0.67, which in absolute value is higher than the average value in the region =0.50. The attenuation para-meter  of the Omori law in the initial phase of attenuation, =–1.26, in absolute value is also higher than the average =1.0 for strong earthquakes in the World. Based on the results of a joint analysis of the focal me-chanism solutions of different agencies and vertical sections along and across the aftershock cloud, it was con-cluded that an upthrust movement occurred in the source along a steep east-south-east nodal plane, dipping to the south. The reason for the activity at the site of the earthquake is the movement of the Indian continent to the north and its collision with Eurasia, as a result of which the separation and subduction of the Hindu Kush plate continue. The Hindu Kush earthquake on October 26, 2015, and its aftershocks are just one of the events of successive deformation and stress relief in the latitudinal zone, marked in 2015 by the migration of earthquake epicenters with KR=13–17 from east to west.

Ras al Khaimah: further archaeological discoveries

Antiquity ◽  
1976 ◽  
Vol 50 (200) ◽  
pp. 216-222
Author(s):  
Beatrice De Cardi
Keyword(s):  
United Arab Emirates ◽  
The State ◽  
Focused Attention ◽  
North East ◽  
The North ◽  
History Of ◽  
The City

Ras a1 Khaimah is the most northerly of the seven states comprising the United Arab Emirates and its Ruler, H. H. Sheikh Saqr bin Mohammad al-Qasimi, is keenly interested in the history of the state and its people. Survey carried out there jointly with Dr D. B. Doe in 1968 had focused attention on the site of JuIfar which lies just north of the present town of Ras a1 Khaimah (de Cardi, 1971, 230-2). Julfar was in existence in Abbasid times and its importance as an entrep6t during the sixteenth and seventeenth centuries-the Portuguese Period-is reflected by the quantity and variety of imported wares to be found among the ruins of the city. Most of the sites discovered during the survey dated from that period but a group of cairns near Ghalilah and some long gabled graves in the Shimal area to the north-east of the date-groves behind Ras a1 Khaimah (map, FIG. I) clearly represented a more distant past.

scholarly journals Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

2021 ◽  
Author(s):  
Xiaoyi Shen ◽  
Chang-Qing Ke ◽  
Bin Cheng ◽  
Wentao Xia ◽  
Mengmeng Li ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Mean Value ◽  
Ocean Model ◽  
North Coast ◽  
Average Value ◽  
The North ◽  
Wind Sea ◽  
The One

AbstractIn August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978–2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.

The San Salvador Earthquake of October 10, 1986—Seismological Aspects and Other Recent Local Seismicity

1987 ◽  
Vol 3 (3) ◽  
pp. 419-434 ◽  
Author(s):  
Randall A. White ◽  
David H. Harlow ◽  
Salvador Alvarez
Keyword(s):  
Main Shock ◽  
Fault Plane ◽  
Vertical Plane ◽  
Aftershock Sequence ◽  
Central American ◽  
Fault Plane Solution ◽  
San Salvador ◽  
The North ◽  
Volcanic Chain ◽  
Plane Solution

The San Salvador earthquake of October 10, 1986 originated along the Central American volcanic chain within the upper crust of the Caribbean Plate. Results from a local seismograph network show a tectonic style main shock-aftershock sequence, with a magnitude, Mw, 5.6. The hypocenter was located 7.3 km below the south edge of San Salvador. The main shock ruptured along a nearly vertical plane toward the north-northeast. A main shock fault-plane solution shows a nearly vertical fault plane striking N32\sz\E, with left-lateral sense of motion. This earthquake is the second Central American volcanic chain earthquake documented with left-lateral slip on a fault perpendicular to the volcanic chain. During the 2 1/2 years preceeding the earthquake, minor microseismicity was noted near the epicenter, but we show that this has been common along the volcanic chain since at least 1953. San Salvador was previously damaged by a volcanic chain earthquake on May 3, 1965. The locations of six foreshocks preceding the 1965 shock show a distinctly WNW-trending distribution. This observation, together with the distribution of damage and a fault-plane solution, suggest that right-lateral slip occurred along a fault sub-parallel with Central American volcanic chain. We believe this is the first time such motion has been documented along the volcanic chain. This earthquake was also unusual in that it was preceded by a foreshock sequence more energetic than the aftershock sequence. Earlier this century, on June 08, 1917, an Ms 6.4 earthquake occurred 30 to 40 km west of San Salvador Volcano. Only 30 minutes later, an Ms 6.3 earthquake occurred, centered at the volcano, and about 35 minutes later the volcano erupted. In 1919 an Ms 6 earthquake occurred, centered at about the epicenter of the 1986 earthquake. We conclude that the volcanic chain is seismically very active with variable styles of seismicity.

DETERMINATION OF THE REPULSIVE FORCE OF A THICK HIGH-COERCIVE PERMANENT MAGNETS IN THE AXIAL BEARING OF A VERTICAL PUMP

2021 ◽  
pp. 23-27
Author(s):  
A. Ya. Krasil’nikov ◽  
A. A. Krasil’nikov
Keyword(s):  
Standard Method ◽  
Permanent Magnets ◽  
Magnetic System ◽  
Repulsive Force ◽  
Cobalt Alloy ◽  
Average Value ◽  
The North ◽  
Repulsive Forces ◽  
North And South

The article considers the possibility of applying a standard method for calculating the repulsive force for a thick high-coercive permanent magnets from samarium-cobalt alloy in a magnetic system. The results of the research allowed us to introduce correction coefficients in the method of calculating the repulsive force in a magnetic system with such magnets, depending on the air gap between of them. It is shown that the repulsive forces of the North poles of permanent magnets differ from the repulsive forces of the South poles. The research was carried out with magnets manufactured by different enterprises. When calculating the repulsive force, the average value of the repulsive force between the North and South poles of magnets is found.

Observations of the Coyote Lake, California earthquake sequence of August 6, 1979

1980 ◽  
Vol 70 (2) ◽  
pp. 559-570 ◽  
Author(s):  
R. A. Uhrhammer
Keyword(s):  
San Francisco ◽  
Fault Zone ◽  
Strong Earthquake ◽  
Main Shock ◽  
B Value ◽  
Aftershock Sequence ◽  
The South ◽  
The North ◽  
Temporal And Spatial Characteristics ◽  
Largest Aftershock

abstract At 1705 UTC on August 6, 1979, a strong earthquake (ML = 5.9) occurred along the Calaveras fault zone south of Coyote Lake about 110 km southeast of San Francisco. This strong earthquake had an aftershock sequence of 31 events (2.4 ≦ ML ≦ 4.4) during August 1979. No foreshocks (ML ≧ 1.5) were observed in the 3 months prior to the main shock. The local magnitude (ML = 5.9) and the seismic moment (Mo = 6 × 1024 dyne-cm from the SH pulse) for the main shock were determined from the 100 × torsion and 3-component ultra-long period seismographs located at Berkeley. Local magnitudes are determined for the aftershocks from the maximum trace amplitudes on the Wood-Anderson torsion seismograms recorded at Berkeley (Δ ≊ 110 km). Temporal and spatial characteristics of the aftershock sequence are presented and discussed. Some key observations are: (1) the first six aftershocks (ML ≧ 2.4) proceed along the fault zone progressively to the south of the main shock; (2) all of the aftershocks (ML ≧ 2.4) to the south of the largest aftershock (ML = 4.4) have a different focal mechanism than the aftershocks to the north; (3) no aftershocks (ML ≧ 2.4) were observed significantly to the north of the main shock for the first 5 days of the sequence; and (4) the b-value (0.70 ± 0.17) for the aftershock sequence is not significantly different from the average b-value (0.88 ± 0.08) calculated for the Calaveras fault zone from 16 yr of data.

A ‘Lengthy Digression’: Why Mining Lagged Elsewhere

2019 ◽  
pp. 163-206
Author(s):  
Jeannette Graulau
Keyword(s):  
The North ◽  
Ore Bodies ◽  
Catchment Areas ◽  
Hindu Kush ◽  
The World ◽  
Mining History ◽  
Silver Mining ◽  
History Of ◽  
Mountain Development ◽  
Mining Regions

This chapter provides the mining history of the mountains of the rest of the world. It begins with England in which major silver discoveries took place in Bere Ferrers or Bere Ferris, a valley of the Tamar River in North Devon, southwest of Dartmoor, and at Combe Martin in the north after the mid-thirteenth century. However, English mines were challenging as they were physically distant from the central arteries of international trade of continental Europe and the commercial cities with continental catchment areas. This chapter also talks about silver mining that flourished in the Persian Province of Khorasan, the Samanid region of Transoxiana, and the Hindu Kush. These are the lands of the most spectacular mountain heights, where mountains piled up one behind another and mountain development assumes its grandest forms. It ends with mining history in India in which its mining exploits did not compete with the achievements of European mining regions. Mining in Zawar endured technical difficulties. Geologist Bagghi states that miners worked on hard siliceous quarzitic ore bodies, where drilling today calls for the use of tungsten carbide bits.

scholarly journals How can we analyze environmental health resilience and vulnerability? A joint analysis with composite indices applied to the north of France

2020 ◽  
pp. 142983
Author(s):  
Delphine Brousmiche ◽  
Michaël Genin ◽  
Florent Occelli ◽  
Lukas Frank ◽  
Annabelle Deram ◽  
...  
Keyword(s):  
Environmental Health ◽  
Joint Analysis ◽  
The North ◽  
Composite Indices

Maximum Earthquake Size and Seismicity Rate from an ETAS Model with Slip Budget

2020 ◽  
Vol 110 (2) ◽  
pp. 874-885
Author(s):  
David Marsan ◽  
Yen Joe Tan
Keyword(s):  
Seismic Moment ◽  
Aftershock Sequence ◽  
Physical Parameters ◽  
Model Parameters ◽  
Seismicity Rate ◽  
Omori Law ◽  
Epidemic Type Aftershock Sequence ◽  
Earthquake Size ◽  
Maximum Earthquake ◽  
Seismicity Model

ABSTRACT We define a seismicity model based on (1) the epidemic-type aftershock sequence model that accounts for earthquake clustering, and (2) a closed slip budget at long timescale. This is achieved by not permitting an earthquake to have a seismic moment greater than the current seismic moment deficit. This causes the Gutenberg–Richter law to be modulated by a smooth upper cutoff, the location of which can be predicted from the model parameters. We investigate the various regimes of this model that more particularly include a regime in which the activity does not die off even with a vanishingly small spontaneous (i.e., background) earthquake rate and one that bears strong statistical similarities with repeating earthquake time series. Finally, this model relates the earthquake rate and the geodetic moment rate and, therefore, allows to make sense of this relationship in terms of fundamental empirical law (the Gutenberg–Richter law, the productivity law, and the Omori law) and physical parameters (seismic coupling, tectonic loading rate).

Low-frequency viscoelastic properties of canine femoral artery in vivo

1979 ◽  
Vol 236 (5) ◽  
pp. H720-H724
Author(s):  
P. Sipkema
Keyword(s):  
Young’S Modulus ◽  
Femoral Artery ◽  
Constant Pressure ◽  
Young's Modulus ◽  
Low Frequency ◽  
Absolute Value ◽  
Average Value ◽  
Mean Pressure ◽  
Frequency Behavior

Mechanical properties of the canine femoral artery in vivo are measured as a function of frequency (0.0025--0.1 Hz) and as a function of mean pressure (10--16 kPa). Sinusoidal pressure variations are generated with a servo-controlled occluder system. The absolute value of the Young's modulus increases with mean pressure (E = 0.63 X 10(5) exp(0.211P)-N.m-2) at 0.05 Hz; where P is pressure. At heart rate frequencies (average value 2.22 Hz) this relation is: E = 1.25 X 10(5) exp(0.175P) N.m-2. The phase angle of the Young's modulus is independent of pressure at both frequencies. At 0.05 Hz we found: phi = 0.189 - 0.00788 P radians and at 2.22 Hz: phi = 0.0723 + 0.000428 P. The slope of both lines is not significantly different from zero slope (alpha = 0.05). Frequency dependence is studied at a constant pressure level (Pr, average value 14.3 kPa) just below the animals' mean pressure levels (average value 15.9 kPa). The frequency behavior of the elastic modulus is fitted with a function with two poles and two zeros (poles at 0.003 and 0.038 Hz; zeros at 0.0022 and 0.03 Hz).

scholarly journals First evaluation of the population structure, genetic diversity and landscape connectivity of the Endangered Arabian tahr

2020 ◽  
Vol 100 (6) ◽  
pp. 659-673
Author(s):  
Steven Ross ◽  
Jean-Marc Costanzi ◽  
Mansoor Al Jahdhami ◽  
Haitham Al Rawahi ◽  
Muhammad Ghazali ◽  
...  
Keyword(s):  
United Arab Emirates ◽  
Landscape Connectivity ◽  
Mitochondrial Control Region ◽  
Landscape Scale ◽  
Population Viability ◽  
Genetic Management ◽  
Base Pairs ◽  
Population Genetic Analysis ◽  
The North ◽  
Genetic Results

AbstractThe Arabian tahr (Arabitragus jayakari) occurs only in the mountains of northern Oman and the United Arab Emirates. The species is classified as Endangered due to its small declining population. In this study, we combined genetic and landscape ecology techniques in order to inform landscape scale conservation and genetic management of Arabian tahr. Using 540 base pairs of mitochondrial control region in a dataset of 53 samples, we found eight haplotypes, which fell into two haplogroups. Population genetic analysis using a panel of 14 microsatellite loci also showed a weak, but significant division. Analyses of landscape connectivity supported the genetic results showing poor connectivity between populations in the far south of the study area and those in the north. The most likely location of corridors connecting Arabian tahr populations were identified. Many corridors between tahr populations are impeded by multi-lane highways and restoration of these connections is required to maintain population viability of Arabian tahr. Owing to limited genetic samples outside of Wadi Sareen, further sampling is needed to elucidate both mtDNA and the nuclear structure of Arabian tahr more fully. Our study provides a toolkit that may be used for future genetic and connectivity monitoring of the Arabian tahr population.

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