美军大型侦察机抵近侦查约1200架次 数次逼近中国大陆领海！数读2021年美军在中国周边行动记录 20211230 |
《今日亚洲》CCTV中文国际
Dec 31, 2021
《今日亚洲》CCTV中文国际
Dec 31, 2021
Australia to get the first of its nuclear submarines FIVE YEARS ahead of schedule as America fast-tracks $90billion project in face of rising tensions with China
Dec. 30 - Rising tensions with China have fast-tracked the delivery of the first Australian nuclear submarine under the $90billion deal with the USA and the UK.
Australia now looks set to launch its first nuclear-powered submarine five years ahead of schedule as the West braces for confrontation with China.
Defence Minister Peter Dutton has revealed the UK and US are 'pulling out all the stops' to speed up the massive project.
The controversial deal - which saw Australia abandon its contract with France for a fleet of diesel submarines - could now see the new subs coming into operation in the first half of the 2030s... more
Dec. 30 - Rising tensions with China have fast-tracked the delivery of the first Australian nuclear submarine under the $90billion deal with the USA and the UK.
Australia now looks set to launch its first nuclear-powered submarine five years ahead of schedule as the West braces for confrontation with China.
Defence Minister Peter Dutton has revealed the UK and US are 'pulling out all the stops' to speed up the massive project.
The controversial deal - which saw Australia abandon its contract with France for a fleet of diesel submarines - could now see the new subs coming into operation in the first half of the 2030s... more
Australia warned bid for nuclear subs carries 'enormous' risks
Dec. 13 - Australia's bid to develop a fleet of nuclear-powered submarines will cost more than US$80 billion and take decades in the "most complex" project the country has ever embarked on, a study released Monday warned.
The report from the Australian Strategic Policy Institute -- an influential Canberra-based think tank -- said ownership of the high-tech subs built with US or British know-how would offer a major advantage in deterring aggression from China or elsewhere.
But it will also be a fiendishly difficult task requiring a step-change in Australia's military and industrial capabilities.
It is "probably the largest and most complex endeavour Australia has embarked upon. The challenges, costs and risks will be enormous," the think tank warned.
"It's likely to be at least two decades and tens of billions of dollars in sunk costs before Australia has a useful nuclear-powered military capability."
The project, announced last month, will make Australia the only non-nuclear weapons power to own nuclear-run submarines, which are capable of travelling quickly over long distances carrying long-range missiles and state-of-the-art underwater drones.
Canberra plans to equip them with conventional rather than nuclear weapons. It has yet to decide whether it will buy US or British technology, what class, size and capabilities the subs will have, where they will be built or how radioactive material will be handled.
Even under an optimistic schedule, the first submarines are unlikely to be operational before 2040, according to the report's authors, who include former Australian defence department officials and an expert on nuclear physics... more
Dec. 13 - Australia's bid to develop a fleet of nuclear-powered submarines will cost more than US$80 billion and take decades in the "most complex" project the country has ever embarked on, a study released Monday warned.
The report from the Australian Strategic Policy Institute -- an influential Canberra-based think tank -- said ownership of the high-tech subs built with US or British know-how would offer a major advantage in deterring aggression from China or elsewhere.
But it will also be a fiendishly difficult task requiring a step-change in Australia's military and industrial capabilities.
It is "probably the largest and most complex endeavour Australia has embarked upon. The challenges, costs and risks will be enormous," the think tank warned.
"It's likely to be at least two decades and tens of billions of dollars in sunk costs before Australia has a useful nuclear-powered military capability."
The project, announced last month, will make Australia the only non-nuclear weapons power to own nuclear-run submarines, which are capable of travelling quickly over long distances carrying long-range missiles and state-of-the-art underwater drones.
Canberra plans to equip them with conventional rather than nuclear weapons. It has yet to decide whether it will buy US or British technology, what class, size and capabilities the subs will have, where they will be built or how radioactive material will be handled.
Even under an optimistic schedule, the first submarines are unlikely to be operational before 2040, according to the report's authors, who include former Australian defence department officials and an expert on nuclear physics... more
Australia-China relations continued to sour in 2021. What can we expect in 2022?
Dec. 29 - It was another tumultuous year for Australia-China relations in 2021, continuing a trend from 2020.
The year began with a World Health Organization (WHO) investigation into the origins of COVID-19, with a delegation sent to Wuhan.
It was something Foreign Minister Marise Payne had called for ahead of other nations, and it made Beijing bristle.
As the year closes out, tensions have taken a sporting turn, with a diplomatic boycott of Beijing's Winter Olympics and speculation swirling around tennis star Peng Shuai.
In between there were other sore points surrounding trade and security: Australia went to the World Trade Organization (WTO) over Chinese tariffs on Australian wine, only for China to lodge its own complaint with the WTO days later.
Ministerial contact between the two nations has apparently been severed, and the ongoing trade tussle has impacted not only wine, but also Australian barley, lobster, beef and coal exports.
Australia also ditched its French submarine deal for AUKUS, a nuclear-powered submarine agreement with the United Kingdom and the United States, in a move widely seen as an attempt to counter China's influence in the Indo-Pacific.
A poll this year showed that trust in China sank to a record low in Australia, with more than 60 per cent of those surveyed saying they view Beijing as a security threat rather than an economic partner.
Pichamon Yeophantong — from the UNSW Canberra at Australian Defence Force Academy — described the relationship as being in a "death spiral", while ANU researcher Ye Xue said the downward trajectory from 2020 was a "new normal".
However, Jennifer Hsu, a research fellow at the Lowy Institute, highlighted that the appointment of a new ambassador to Australia might be the best opportunity to hit the restart button on a rocky path... more
Dec. 29 - It was another tumultuous year for Australia-China relations in 2021, continuing a trend from 2020.
The year began with a World Health Organization (WHO) investigation into the origins of COVID-19, with a delegation sent to Wuhan.
It was something Foreign Minister Marise Payne had called for ahead of other nations, and it made Beijing bristle.
As the year closes out, tensions have taken a sporting turn, with a diplomatic boycott of Beijing's Winter Olympics and speculation swirling around tennis star Peng Shuai.
In between there were other sore points surrounding trade and security: Australia went to the World Trade Organization (WTO) over Chinese tariffs on Australian wine, only for China to lodge its own complaint with the WTO days later.
Ministerial contact between the two nations has apparently been severed, and the ongoing trade tussle has impacted not only wine, but also Australian barley, lobster, beef and coal exports.
Australia also ditched its French submarine deal for AUKUS, a nuclear-powered submarine agreement with the United Kingdom and the United States, in a move widely seen as an attempt to counter China's influence in the Indo-Pacific.
A poll this year showed that trust in China sank to a record low in Australia, with more than 60 per cent of those surveyed saying they view Beijing as a security threat rather than an economic partner.
Pichamon Yeophantong — from the UNSW Canberra at Australian Defence Force Academy — described the relationship as being in a "death spiral", while ANU researcher Ye Xue said the downward trajectory from 2020 was a "new normal".
However, Jennifer Hsu, a research fellow at the Lowy Institute, highlighted that the appointment of a new ambassador to Australia might be the best opportunity to hit the restart button on a rocky path... more
Plate tectonics (from the Late Latin: tectonicus, from the Ancient Greek: τεκτονικός, lit. 'pertaining to building')[1] is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large of tectonic plates which have been slowly moving since about 3.4 billion years ago.[2] The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century. Plate-tectonics came to be generally accepted by geoscientists after seafloor spreading was validated in the mid to late 1960s.
Earth's lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken into seven or eight major plates (depending on how they are defined) and many minor plates. Where the plates meet, their relative motion determines the type of boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries (or faults). The relative movement of the plates typically ranges from zero to 10 cm annually.[3]
Tectonic plates are composed of the oceanic lithosphere and the thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, the process of subduction, or one plate moving under another, carries the edge of the lower one down into the mantle; the area of material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total geoid surface area of the lithosphere remains constant. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories, since disproven, proposed gradual shrinking (contraction) or gradual expansion of the globe.[4]
Tectonic plates are able to move because Earth's lithosphere has greater mechanical strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection; that is, the slow creeping motion of Earth's solid mantle. Plate movement is thought to be driven by a combination of the motion of the seafloor away from spreading ridges due to variations in topography (the ridge is a topographic high) and density changes in the crust (density increases as newly-formed crust cools and moves away from the ridge). At subduction zones the relatively cold, dense oceanic crust is "pulled" or sinks down into the mantle over the downward convecting limb of a mantle cell.[5] Another explanation lies in the different forces generated by tidal forces of the Sun and the Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.
Earth's lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken into seven or eight major plates (depending on how they are defined) and many minor plates. Where the plates meet, their relative motion determines the type of boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries (or faults). The relative movement of the plates typically ranges from zero to 10 cm annually.[3]
Tectonic plates are composed of the oceanic lithosphere and the thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, the process of subduction, or one plate moving under another, carries the edge of the lower one down into the mantle; the area of material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total geoid surface area of the lithosphere remains constant. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories, since disproven, proposed gradual shrinking (contraction) or gradual expansion of the globe.[4]
Tectonic plates are able to move because Earth's lithosphere has greater mechanical strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection; that is, the slow creeping motion of Earth's solid mantle. Plate movement is thought to be driven by a combination of the motion of the seafloor away from spreading ridges due to variations in topography (the ridge is a topographic high) and density changes in the crust (density increases as newly-formed crust cools and moves away from the ridge). At subduction zones the relatively cold, dense oceanic crust is "pulled" or sinks down into the mantle over the downward convecting limb of a mantle cell.[5] Another explanation lies in the different forces generated by tidal forces of the Sun and the Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.
板块构造论（又稱板块构造假说、板块构造学说或板块构造学，總稱「板塊漂移」）是为了解释大陆漂移现象而发展出的一种地质学理论。该理论认为，地球的岩石圈是由板块拼合而成；现今的全球分为六大板块（1968年法国勒皮雄划分），海洋和陆地的位置是不断变化的。根据这种理论，地球内部构造的最外层分为两部分：外层的岩石圈和内层的软流圈。这种理论基于两种独立的地质观测结果：海底擴張和大陆漂移。
圈可以分為大板塊及小板塊，兩板塊相接觸的部份則可依其相對運動來分為分離板塊邊緣、聚合板塊邊緣及轉形斷層。在板塊邊緣常會出現地震、火山、造山運動及海沟。现今每年的相對運動距離約在0至150 mm不等[1]。
板塊可以分為海洋板塊及較厚的陸地板塊，兩者都有各自的地殼。在聚合板塊邊緣會有隱沒帶，會將板塊沉降至地幔，使岩石圈質量減少，而分離板塊邊緣因海底擴張形成的新地殼，這種對板塊的預測稱為輸送帶原理。較早期的理論認為地球會漸漸膨脹或是漸漸收縮，也都還有一些人支持[2]。
板塊可以移動的原因是因為岩石圈的強度比下方的軟流圈要大，地幔密度的變化造成了地幔對流。一般認為板塊運動是由海底遠離擴張脊的運動（因為地形及地殼的變化，造成地球引力的差異）、阻力及隱沒帶向下的吸力等影響組合而成。另一種解釋則是考慮地球旋轉的受力差異，以及太陽及月亮的潮汐力。這些因素之間的相對重要性及其關係還不清楚，目前也還有許多爭議。
圈可以分為大板塊及小板塊，兩板塊相接觸的部份則可依其相對運動來分為分離板塊邊緣、聚合板塊邊緣及轉形斷層。在板塊邊緣常會出現地震、火山、造山運動及海沟。现今每年的相對運動距離約在0至150 mm不等[1]。
板塊可以分為海洋板塊及較厚的陸地板塊，兩者都有各自的地殼。在聚合板塊邊緣會有隱沒帶，會將板塊沉降至地幔，使岩石圈質量減少，而分離板塊邊緣因海底擴張形成的新地殼，這種對板塊的預測稱為輸送帶原理。較早期的理論認為地球會漸漸膨脹或是漸漸收縮，也都還有一些人支持[2]。
板塊可以移動的原因是因為岩石圈的強度比下方的軟流圈要大，地幔密度的變化造成了地幔對流。一般認為板塊運動是由海底遠離擴張脊的運動（因為地形及地殼的變化，造成地球引力的差異）、阻力及隱沒帶向下的吸力等影響組合而成。另一種解釋則是考慮地球旋轉的受力差異，以及太陽及月亮的潮汐力。這些因素之間的相對重要性及其關係還不清楚，目前也還有許多爭議。
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