scholarly journals Meso-Cenozoic Exhumation of the Linqing Sub-Basin, Bohai Bay Basin: Implications for Cratonic Destruction

Minerals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1176
Author(s):  
Wei Xu ◽  
Nansheng Qiu ◽  
Jian Chang
Keyword(s):  
Eastern China ◽  
Age Groups ◽  
Philippine Sea Plate ◽  
Bohai Bay ◽  
Tectonic Event ◽  
The North ◽  
Tectonic Events ◽  
Minimum Age ◽  
Age Profile ◽  
Tethys Ocean

The relationship between the tectonic event of the Linqing Sub-basin and the destruction of the North China Craton (NCC) is an important factor to consider when studying geodynamic mechanisms in eastern China. In the current study, we present a low-temperature apatite thermochronological analysis of 14 samples to study the tectonic event of the Linqing Sub-basin. Our data showed that the apatite fission track (AFT) ages were in the range of 53.5–124.4 Ma, and the average track lengths were 8.00–11.24 μm. The grain ages showed that 10 samples had mixed ages and were characterized by discordant distribution. The minimum ages decomposed from AFT ages mainly ranged from 105.3 to 40.8 Ma. We identified a break-in-slope from the depth-minimum age profile, which was related to the Meso-Cenozoic tectonic event. The AFT age data could be decomposed into three age groups, namely, P3 (394.8–215.7 Ma), P2 (124.6–83.4 Ma), and P1 (70.7–40.8 Ma), indicating three significant tectonic events in the NCC. P3 is related to the uplift of the NCC at 445.0–315.0 Ma and deformation and magmatism at 320.0–200.0 Ma. P2 corresponds to the Mesozoic tectonic activities, such as the closure of the Mongol–Okhotsk Ocean, the turning of the Izanagi plate and mantle convection. P1 mainly corresponds to the Izanagi–Pacific ridge, the closure of the Tethys Ocean, and the rotation of the Philippine Sea plate in the Cenozoic. Our study provides evidence for the destruction of the NCC, and has significance for the understanding of the deep mechanism.

Stress induced by the Mio-Pliocene Alpine collision in northern France

2005 ◽  
Vol 176 (4) ◽  
pp. 319-328 ◽  
Author(s):  
Muriel Rocher ◽  
Marc Cushing ◽  
Francis Lemeille ◽  
Stéphane Baize
Keyword(s):  
Tectonic Stress ◽  
Western Alps ◽  
Mechanical Twinning ◽  
Paris Basin ◽  
Tectonic Event ◽  
Stress Regime ◽  
The North ◽  
Tectonic Events ◽  
Calculated Stress ◽  
Appalachian Foreland

Abstract In most rocks, tectonic stress induces crystalline deformation, such as mechanical twinning. The inverse analysis of calcite twinning allows reconstruction of both directions and values of the paleostress field. The Etchecopar inverse method using calcite twinning has been improved in this paper, lowering the uncertainties on the calculated stress values. Calcite was sampled in the foreland of the western Alps, along a SE-NW section from the Jura Mountains to the Isle of Wight. The calcite twinning inversion has identified the successive Cenozoic tectonic events, named “Pyrenean” compression, “Oligocene” extension and “Alpine” compression. The distribution of the Mio-Pliocene Alpine orogenic stress was specified. This stress field varies in terms of stress regime, directions and values. The horizontal principal stress trends E-W in southern France, WNW in the centre, and NW in the North, which can be attributed to the Alpine indenter phenomenon. The tectonic stress regime roughly corresponds to a pure compression in the Jura and rapidly evolves to the NW to a strike-slip state of stress, then beyond the Paris basin’s centre to a perpendicular extension. Unlike the Pyrenean or Appalachian foreland stress, the Alpine differential stress does not significantly decrease from the Jura front to the far field (30 to 25 MPa). Moreover, stress values vary from one area to another, low in the Burgundy high, fractured and uprising during this tectonic event, and high in Paris basin centre, poorly fractured and subsiding during this event. Three possible explanations are proposed : variation in crust thickness, crustal buckling during the Mio-Pliocene, and pre-existing fractures.

Sedimentary deformation features as evidence for paleoseismic events in the middle Eocene in the Dongying Depression of the southern Bohai Bay Basin, eastern China

2020 ◽  
Vol 57 (8) ◽  
pp. 954-970
Author(s):  
Zhongshuai Hou ◽  
Shiyue Chen ◽  
Shun Zhang ◽  
Huaiyu Yang
Keyword(s):  
Middle Eocene ◽  
Eastern China ◽  
Active Faults ◽  
Bohai Bay ◽  
Bohai Bay Basin ◽  
The North ◽  
Dongying Depression ◽  
Gravity Flows ◽  
Tectonically Active ◽  
Deformation Features

Cores from the middle Eocene sediments of the Dongying Depression of the southern Bohai Bay Basin in east China yield various kinds of sedimentary deformation structures. They include microfolds, load casts, flame structures, ball-and-pillow structures, load-cast ripples, pinch-and-swell structures, boudinage structures, sand dikes, microfaults, and cataclastic breccias. Gravity flows, including turbidites and debris flows, also occur in the study area. The deformation layers can be divided into plastic deformation and brittle deformation types. These develop in a succession composed mainly of dark finely laminated and massive mudstone interbedded with thin sandstones and carbonate rocks that accumulated in a low-energy semi-deep to deep lacustrine environment in a tectonically active setting. Considering the facies attributes in the study area, intrinsically possible trigger mechanisms such as rapid sediment loading and storm currents are absent. Thus, the sedimentary deformation features should be induced by seismic activity, and the same with the gravity flows. These seismites are interpreted to have originated from earthquakes with magnitudes exceeding M 5.6. Basin-controlling faults in the north border of Dongying Depression give rise to the occurrence of seismites. The increasing occurrence frequency of seismites from Es4u to Es3l corresponds with the increase in the activity velocity of the basin-controlling faults. Compared with the seismites developed in other fault depressions in the Bohai Bay Basin, seismites developed in the Dongying Depression are relatively smaller scale and are dominated by microfault layers, relatively more cohesive sediments, and greater distance between seismites and active faults results in the occurrence of these features.

Late Precambrian structural evolution of Pigeon Point, Minnesota and relations to the Lake Superior syncline

1976 ◽  
Vol 13 (7) ◽  
pp. 877-888 ◽  
Author(s):  
M. G. Mudrey Jr.
Keyword(s):  
Lake Superior ◽  
Volcanic Rocks ◽  
Structural Evolution ◽  
Cook County ◽  
Tectonic Event ◽  
Late Precambrian ◽  
North Shore ◽  
Volcanic Group ◽  
The North ◽  
Tectonic Events

A sequence of semi-brittle deformational tectonic events in gently dipping middle Precambrian argillite and graywacke, and late Precambrian sandstone and volcanic rocks on the northwest coast of Lake Superior is interpreted from detailed geologic mapping in the Pigeon Point, Cook County, Minnesota area. The earliest tectonic event was broad, open folding in the middle Precambrian Rove Formation along N 35 °E axes and the development of two sets of joints (North and N 70° E). The second event was eastward trending, high-angle faulting in the Rove Formation and the disconformably overlying late Precambrian Puckwunge sandstone and North Shore Volcanic Group; the south sides moved upward relative to the north sides. These faults and associated joints were the loci of emplacement of 'early mafic' dikes of ilmenite-bearing diabase, which probably correlate with the 'Logan intrusions'. Subsequently, east-northeastward trending olivine diabase sills and dikes were emplaced in the Rove Formation and the North Shore Volcanic Group, and they cross-cut the early mafic dikes and sills. The third event occurred after cessation of igneous activity; two sets of regional joints (N 14 °W and N 53 °E) were formed, apparently as a result of fracturing accompanying initial subsidence of the so-called 'Lake Superior syncline' to the southeast. The fourth event was the development of a zone of cataclastic rock trending N 65 °E from the Pigeon Point area northeastward at least 60 km. To the north of this fracture zone, bedding in the Rove Formation dips 15–25 °SE. Copper and silver mineralization was subsequently emplaced within this fracture zone.The first three tectonic events appear to represent reactivation of structures of early Precambrian age, and appear to control the general outcrop pattern. The fourth event is an entirely Keweenawan feature, and marks the beginning of subsidence of the 'Lake Superior syncline'. It may correlate in time with the deposition of the Copper Harbor Conglomerate, and other late middle Keweenawan events.

Structure and dynamics in the north Jizhong depression, Bohai bay basin, eastern china

2016 ◽  
Author(s):  
Quanyun Miao ◽  
Jiafu Qi ◽  
Yueqi Dong ◽  
Bingshan Ma ◽  
Qiang Gao ◽  
...  
Keyword(s):  
Eastern China ◽  
Bohai Bay ◽  
Bohai Bay Basin ◽  
Structure And Dynamics ◽  
The North ◽  
Jizhong Depression

scholarly journals Updated Incidence of Thyroid Cancer in the North East Region of Romania after 35 Years of Chernobyl Fallout. Is There a Link between?

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 907
Author(s):  
Laura Teodoriu ◽  
Maria Christina Ungureanu ◽  
Letitia Leustean ◽  
Cristina Preda ◽  
Delia Ciobanu ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Age Distribution ◽  
Age Groups ◽  
Chernobyl Fallout ◽  
Statistical Correlations ◽  
North East ◽  
The North ◽  
East Region ◽  
Radioactive Cloud ◽  
The Moment

Thyroid cancer (TC) represents a worldwide problem, the consistent growth of the incidence increment issues about management of risk factors and curative treatment. Updated statistical data are not complete in the North East region of Romania and need to be improved. Therefore, through this study, we aim to renew the existing data on thyroid cancer. We conducted a retrospective study covering a period of 10 years. Data were collected from a hospital information system (InfoWorld) between 2009 and 2019. Patients’ age groups were stratified in relation with the age at the moment of the Chernobyl event. A database was obtained (Microsoft Excel) and statistical correlations were applied. In the studied period, 1159 patients were diagnosed: 968 females and 191 males, distributed by region, with the highest addressability in Iasi (529), followed by neighboring counties. Age distribution displayed that most of the thyroid cancers were in the range 4060 years old (50.94%), followed by 60–80 years old (32.41%). Most patients were diagnosed with papillary carcinoma 63.10%, then follicular 14.7%, medullary 6.74% and undifferentiated 1.02%. Romania was in the vicinity of the radioactive cloud at Chernobyl fallout, so we must deliberate whether the increased incidence of thyroid cancer in the age group 40–60 years is associated with radiogenicity (iodine 131) given the fact that over has 35 years and the half-life of other radioisotopes like Caesium-137 and Strontium -90 is completed.

scholarly journals Japan’s voluntary lockdown: further evidence based on age-specific mobile location data

2021 ◽  
Author(s):  
Tsutomu Watanabe ◽  
Tomoyoshi Yabu
Keyword(s):  
Age Groups ◽  
Evidence Based ◽  
Intervention Effect ◽  
Information Effect ◽  
Mobile Location ◽  
Serious Illness ◽  
Location Data ◽  
Voluntary Response ◽  
Younger Age ◽  
Age Profile

AbstractChanges in people’s behavior during the COVID-19 pandemic can be regarded as the result of two types of effects: the “intervention effect” (changes resulting from government orders for people to change their behavior) and the “information effect” (voluntary changes in people’s behavior based on information about the pandemic). Using age-specific mobile location data, we examine how the intervention and information effects differ across age groups. Our main findings are as follows. First, the age profile of the intervention effect shows that the degree to which people refrained from going out was smaller for older age groups, who are at a higher risk of serious illness and death, than for younger age groups. Second, the age profile of the information effect shows that the degree to which people stayed at home tended to increase with age for weekends and holidays. Thus, while Acemoglu et al. (2020) proposed targeted lockdowns requiring stricter lockdown policies for the oldest group in order to protect those at a high risk of serious illness and death, our findings suggest that Japan’s government intervention had a very different effect in that it primarily reduced outings by the young, and what led to the quarantining of older groups at higher risk instead was people’s voluntary response to information about the pandemic. Third, the information effect has been on a downward trend since the summer of 2020. It is relatively more pronounced among the young, so that the age profile of the information effect remains upward sloping.

scholarly journals Disease-modifying therapy prescription patterns in people with multiple sclerosis by age

2021 ◽  
Vol 14 ◽  
pp. 175628642110064
Author(s):  
Yinan Zhang ◽  
Amber Salter ◽  
Shan Jin ◽  
William J. Culpepper ◽  
Gary R. Cutter ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Disease Activity ◽  
Age Groups ◽  
The Elderly ◽  
Department Of Veterans Affairs ◽  
Real World Data ◽  
Research Committee ◽  
The North ◽  
Disease Modifying ◽  
Magnetic Resonance Imaging Mri

Background: Disease-modifying therapies (DMTs) for multiple sclerosis (MS) are approved for their ability to reduce disease activity, namely clinical relapses and signal changes on magnetic resonance imaging (MRI). Disease activity appears age dependent. Thus, the greatest benefit would be expected in younger people with MS (PwMS) whereas benefits in the elderly are uncertain. Methods: Real-world data were obtained from PwMS from the North American Research Committee on Multiple Sclerosis (NARCOMS) registry and the US Department of Veterans Affairs Multiple Sclerosis Surveillance Registry (MSSR). Results: 6948 PwMS were surveyed from NARCOMS, and the MSSR had 1719 participants. In younger adult PwMS 40-years old or less, 183 (61.4%) in NARCOMS and 179 (70.5%) in the MSSR were prescribed DMTs. Among PwMS over age 60, 1575 (40.1%) in NARCOMS and 239 (36.3%) in the MSSR were prescribed DMTs. More PwMS in the age group of 31–40 ( p = 0.035) and 41–50 ( p = 0.001) in the MSSR were using DMTs compared with PwMS of the same age groups in NARCOMS. Conclusion: These findings suggest that DMTs are under-utilized in the younger population and continue to be commonly prescribed in the elderly. Broader access may explain the higher prescription rate of DMTs in US veterans.

scholarly journals Colonoscopy and Flexible Sigmoidoscopy Practice Patterns in Ontario: A Population-Based Study

2007 ◽  
Vol 21 (7) ◽  
pp. 431-434 ◽  
Author(s):  
Susan E Schultz ◽  
Chris Vinden ◽  
Linda Rabeneck
Keyword(s):  
Flexible Sigmoidoscopy ◽  
Practice Patterns ◽  
Age Groups ◽  
Population Based ◽  
Insurance Plan ◽  
Ontario Health Insurance Plan ◽  
Population Based Study ◽  
The North ◽  
General Surgeons ◽  
Statistics Canada

OBJECTIVE: To conduct a population-based study on the provision of large bowel endoscopic services in Ontario.METHODS: Data from the following databases were analyzed: the Ontario Health Insurance Plan, the Institute for Clinical Evaluative Sciences Physicians Database and Statistics Canada. The flexible sigmoidoscopy and colonoscopy rates per 10,000 persons (50 to 74 years of age) by region between April 1, 2001, and March 31, 2002, were calculated, as well as the numbers and types of physicians who performed each procedure.RESULTS: In 2001/2002, a total of 172,108 colonoscopies and 43,400 flexible sigmoidoscopies were performed in Ontario for all age groups. The colonoscopy rate was approximately five times that of flexible sigmoidoscopy; rates varied from 463.1 colonoscopies per 10,000 people in the north to 286.8 colonoscopies per 10,000 people in the east. Gastroenterologists in all regions tended to perform more procedures per physician, but because of the large number of general surgeons, the total number of procedures performed by each group was almost the same.CONCLUSION: Population-based rates of colonoscopies and flexible sigmoidoscopies are low in Ontario, as are the procedure volumes of approximately one-quarter of physicians.

The Strength Analysis of Francis Turbine Runner Based on the Fluid-Solid Coupling

2014 ◽  
Vol 709 ◽  
pp. 41-45
Author(s):  
Kan Kan ◽  
Yuan Zheng ◽  
Xin Zhang ◽  
Bin Sun ◽  
Hui Wen Liu
Keyword(s):  
Water Pressure ◽  
Eastern China ◽  
Static Stress ◽  
Operating Conditions ◽  
Francis Turbine ◽  
Strength Analysis ◽  
Maximum Deformation ◽  
The North ◽  
North Eastern ◽  
Turbine Runner

This paper does unidirectional fluid-solid coupling calculation on the runner strength under three designed head loading conditions of a certain Francis turbine in the north-eastern China. The water pressure on the blade in the flow fields of different operating conditions is calculated by means of CFD software CFX. With the help of ansys workbench, the water pressure is loaded to the blade as structural load to conclude the static stress distribution and deformation of the runner under different operating conditions. The results show that the maximum static stress increases with the rise of the flow and appears near the influent side of the blade connected to the runner crown; the maximum deformation increases with the rise of the flow and appears on the band. The results provides effective basis for the structural design and safe operation of the Francis turbine.

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