Characteristics of Authigenic Pyrite and its Sulfur Isotopes Influenced by Methane Seep--Taking the Core A at Site 79 of the Middle Okinawa Trough as an Example

Objective Authigenic pyrite often develops extensively in marine sediments,which is an important product of sulfate reduction in an anoxic environment.It has a specific appearance and complicated sulfur isotopic properties,and acts as important evidence of methane seep in marine sediments.Strong AOM（anaerobic oxidation of methane）activity has developed in the Okinawa Trough.

Relic Oceanic Crust at Sub-Arc Depth: An Example from UHP Eclogites Enclosed in Serpentinites from the Southwestern Tianshan, China

Ultra-high pressure（UHP）eclogites that derive from subducted oceanic crust are rarely found at the Earth’s surface because they need to be enclosed in a buoyant host rock such as serpentinites that facilitate exhumation（Hermann et al.,2000;Guillot et al.,2001）.Under normal subduction geotherms,serpentinites break down just before UHP conditions are reached and therefore most of the exhumed eclogites representing subducted oceanic crust formed under fore-arc conditions.We investigated eclogite blocks enclosed into serpentinites that occur in the southwestern Tianshan oceanic subduction,China.A previous study proved that the serpentinites derive from altered oceanic crust and experienced UHP metamorphism at low temperatures of 510-530°C（Shen et al.,2015）.Three relatively fresh eclogite samples were studied in detail.Sample 129-7 shows the retrograde mineral assemblage of amphibole+biotite+albite+chlorite+minor titanite and peak metamorphic relics of omphacite+garnet±chlorite.Sample C107-23 is mainly composed of amphibole+albite+chlorite+zoisite+muscovite+minor titanite as a retrograde assemblage and garnet+phengite as the peak metamorphic relics with omphacite only found as inclusions in garnet.Similar to sample C107-23,sample C11066 preserves large-grained euhedral to subhedral garnet relics with omphacite inclusions,and epidote,diopside,amphibole,muscovite,chlorite,albite and biotite are in the matrix belong to the retrograde assemblage.These three retrograde eclogite samples were modelled using thermodynamic calculations in the Mn NCKFMSHO（Mn O-Na;O-Ca O-K;O-FeO-Mg O-Al;O;-SiO;-H;O-Fe;O;）system.Based on the peak assemblage of omphacite+garnet and the crossing of the grossular and pyrope isopleths in garnet,peak P-T conditions of;60-470oC,28-29 kbar（129-7）,450-500oC,28-35 kbar（C107-23）,;75-505oC,26-29 kbar（C11066）were calculated.The retrograde assemblages indicate near isothermal decompression resulting in a clockwise P-T evolution of these eclogites.The peak metamorphic pressures at 500°C are well within UHP conditions（coesite stability field）and are within error the same as peak conditions of the host serpentinites（Shen et al.,2015）.This provides evidence that eclogites and serpentinites shared the same evolution.We infer that the subducted low-density serpentinites were assembled with the high-density eclogites during subdution and helped the latter to exhume back to the surface.The studied eclogites thus represent rare examples of relics of oceanic crust that was subducted to sub-arc depth.

Relic Oceanic Crust at Sub-arc Depth: an Example from UHP Eclogites Enclosed in Serpentinites from the Southwestern Tianshan Mountains, China

Ultra-high pressure(UHP)eclogites that derive from subducted oceanic crust are rarely found at the Earth’s surface because they need to be enclosed in a buoyant host rock such as serpentinites that facilitate exhumation

An Example of the Scientists—Congratulate Professor SHI Changxu on His Seventyth Birthday

November 15 is the seventyth anniver-sary of Prof.SHI Changxu(C.H.Shih),honorary director of the Institute of MetalResearch,Academia Sinica.As a memberof Chinese Academy of Sciences and direc-tor of the First Division of Technical Sci-ence,Academia Sinica,vice president ofthe National Natural Science Foundation ofChina,and editor-in-chief of ActaMetallurgica Sinica,Prof.Shi is learnedand distinguished in his study,and showsenergy and initiative in his work.And he isextremely loyal and devoted to his countryand his people,so that he commands ourdeep respect and sets an example to the

Application of High-Resolution Remote Sensing Technology in Quantitative Study on Coseismic Surface Rupture Zones: An Example of the 2008 M_w7.2 Yutian Earthquake

Objective Nowadays, high-resolution remote sensing technology has brought new changes to surveys of earthquakes, and the quantitative study of seismic faults based on this technology has become a trend in the world(Barzegari et al., 2017). An Mw 7.2 earthquake occurred in Yutian of Xinjiang on the western end of the Altyn Tagh fault on March 21 st, 2008. It is difficult to access this depopulated zone because of the high altitude and only 1–2 months of snowmelt. This study utilized high-resolution

How do domestic garment enterprises achieve breakthrough and Transformation, taking Zhejiang as an example

Located in southeast of Hangzhou,Wubao village was well-known in the province for its garment processing plants.Five years ago,the village garment industry reached the peak,with more than 900 processing plants and annual production of 60 million garments.Today,the village is quiet,because more than half of the so called'low-end,small,scattered'processing workshops initiatively withdrew from the market competition due to backward technol-

Imbalance Between Scientific Technology and Human Rights and Measures to Rectify the Imbalance——Taking Geological Disasters as an Example

I. Increase in Human Activity and Occurrence of Geological Disasters ＂A geological disaster is a natural disaster that happens in a geo- logical environment. It is a geological effect （phenomenon） caused or in- fluenced by Nature and （or） human factors that leads to losses to human life, property and the environment.TM Based on their cause, geological disasters can be divided into natural geological and artificial geological disasters. Natural geological disas- ters include those caused by natural effects. These include typhoons, rain- fall, melting snow and earthquakes,

How ancient Chinese constellations are applied in the city planning?An example on the planning principles employed in Xianyang,the capital city of Qin Dynasty

As the first empire of imperial China,the Qin Dynasty is a crucial period for the establishment of China’s territory,nationality,political system and academic thoughts[1].The planning and construction history of Xianyang,the capital city of the Qin,can be dated from the 12th year of the King of Qin Dynasty,Qinxiaogong(350 BC)to the death of the Second Emperor of Qin(206 BC)spanning a total of144 years.During that time,Xianyang was

HOW TO CONDUCT A GOOD CLINICAL TRIAL: AN EXAMPLE OF CHINESE HERBS FOR PSORIASIS

It is important for high-quality trials to be conducted in compliance with GCP principles and the CONSORT statement.We showed an example of such trial.A double-blind,randomized,placebo-controlled trial was conducted,aimed to evaluate the effectiveness and safety of formula PSORI-CM01 for psoriasis.A pilot study was performed to assess the feasibility of the trial.For

The Controlled Approach in City Planning:Technique and Practice---Take,as an example,the control type of planning for the developing area of Chigang in Guangzhou

On the basis of the practice in Guangzhou in recent years,this article proposes the tech-nique of the“control”approach in city planning,and presents its specific application and ex-plorations with the example of the planning for the developing area of Chigang inGuangzhou.With the reform of the urban economic-political system and the advancement of theopen-door policy,significant changes are evolving in the ideas and the ways of city planningand design.To meet the demand of these developments,the new“control”approach in cityplanning and design is thus adopted.

Quantum and Classical Approach Applied to the Motion of a Celestial Body in the Solar System

According to the classical mechanics the energy of a celestial body circulating in the solar system is a constant term. This energy is defined by the masses product of the larger and smaller body entering into a mutual attraction as well as the size of the major semiaxis characteristic for the corresponding Kepler orbit. A special situation concerns the planet interaction with the Sun because of a systematic decrease of the Sun mass due to the luminosity effect. The aim of the paper is to point out that even in the case of perfectly constant interacting masses the energy of the moving body should decrease when a quantum treatment of the body motion is considered. The rate of the energy decrease is extremely small, nevertheless it gives a shortening of the distance between the interacting bodies leading to a final effect of a touch of the larger body and a smaller one.

Conservation of Energy in Classical Mechanics and Its Lack from the Point of View of Quantum Theory

It is pointed out that the property of a constant energy characteristic for the circular motions of macroscopic bodies in classical mechanics does not hold when the quantum conditions for the motion are applied. This is so because any macroscopic body—lo-cated in a high-energy quantum state—is in practice forced to change this state to a state having a lower energy. The rate of the energy decrease is usually extremely small which makes its effect uneasy to detect in course of the observations, or experiments. The energy of the harmonic oscillator is thoroughly examined as an example. Here our point is that not only the energy, but also the oscillator amplitude which depends on energy, are changing with time. In result, no constant positions of the turning points of the oscillator can be specified;consequently the well-known variational procedure concerning the calculation of the action function and its properties cannot be applied.