It is generally acknowledged that geomagnetic polarity has reversed many times in geological history and an abnormal geologic phenomenon is the Cretaceous normal superchron. However, the causes have been unknown up to...It is generally acknowledged that geomagnetic polarity has reversed many times in geological history and an abnormal geologic phenomenon is the Cretaceous normal superchron. However, the causes have been unknown up to now. The nonlinear theory has been applied to analyze the phenomenon in geomagnetic polarity reversal and the Cretaceous normal superchron. The Cretaceous normal superchron implies that interaction of the Earth's core-mantle and liquid movement in the outer core may be the lowest energy state and the system of Earth magnetic field maintains a sort of temporal or spatial order structure by exchanging substance and energy in the outside continuously. During 121-83 Ma, there was no impact of a celestial body that would result in a geomagnetic polarity reversal, which may be a cause for occurrence of the Cretaceous normal superchron.The randomness of geomagnetic polarity reversal has the self-reversion characteristic of chaos and the chaos theory gives a simple and clear explanation for the dynamic cause of the geomagnetic polarity reversal.展开更多
The existing data on the confirmed extraterrestrial impacts and geomagnetic reversals are examined. Differential rotation of the inner core of the Earth relative to the rest of the planet has been observed through sei...The existing data on the confirmed extraterrestrial impacts and geomagnetic reversals are examined. Differential rotation of the inner core of the Earth relative to the rest of the planet has been observed through seismic records. Differential rotation between the inner and outer core is thought to be related to the geomagnetic field of the Earth. Extraterrestrial impacts with the surface of the Earth have been shown to cause changes in this differential rotation. It is shown in this paper that there is a strong correlation between the dates of major impacts and geomagnetic reversals. This strongly supports the possibility of major extraterrestrial impacts being one of the causes of geomagnetic reversals as has been suggested previously.展开更多
The origin of the earth’s magnetic field is one of the five most important unsolved problems in physics, especially geomagnetic polarity reversal remains one of Nature’s most enigmatic phenomena. It is proposed that...The origin of the earth’s magnetic field is one of the five most important unsolved problems in physics, especially geomagnetic polarity reversal remains one of Nature’s most enigmatic phenomena. It is proposed that the geomagnetic polarity reversal links with some global-geology events, although it is difficult to clarify the mechanism of this correlation. The history of continental structures in eastern China would be also linked with some global-geology events.展开更多
A statistical model for the quick reversals during a geomagnetic pole transition is put forward by combining the modern geomagnetic field and paleomagnetic field. The decrease of geomagnetic intensity determines the r...A statistical model for the quick reversals during a geomagnetic pole transition is put forward by combining the modern geomagnetic field and paleomagnetic field. The decrease of geomagnetic intensity determines the reversals, and the quick reversals are possibly caused by the interaction between g10 and the other geomagnetic components.展开更多
The International Geomagnetic Reference Field models (IGRF) for 1900-2000 are used to calculate the geomagnetic field distribution in the Earth' interior from the ground surface to the core-mantle boundary (CMB) u...The International Geomagnetic Reference Field models (IGRF) for 1900-2000 are used to calculate the geomagnetic field distribution in the Earth' interior from the ground surface to the core-mantle boundary (CMB) under the assumption of insulated mantle. Four reversed polarity patches, as one of the most important features of the CMB field, are revealed. Two patches with +Z polarity (downward) at the southern African and the southern American regions stand out against the background of -Z polarity (upward) in the southern hemisphere, and two patches of -Z polarity at the North Polar and the northern Pacific regions stand out against the +Z background in the northern hemisphere. During the 1900-2000 period the southern African (SAF) patch has quickly drifted westward at a speed of 0.2-0.3°/a; meanwhile its area has expanded 5 times, and the magnetic flux crossing the area has intensified 30 times. On the other hand, other three patches show little if any change during this 100-year period. Extending upward, each of the reversed polarity patches at the CMB forms a chimney-shaped 'reversed polarity column' in the mantle with the bottom at the CMB. The height of the SAF column has grown rapidly from 200km in 1900 to 900km in 2000. If the column grows steadily at the same rate in the future, its top will reach to the ground surface in 600-700 years. And then a reversed polarity patch will be observed at the Earth's surface, which will be an indicator of the beginning of a magnetic field reversal. On the basis of this study, one can describe the process of a geomagnetic polarity reversal, the polarity reversal may be observed firstly in one or several local regions; then the areas of these regions expand, and at the same time, other new reversed polarity regions may appear. Thus several poles may exist during a polarity reversal.展开更多
The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain unknown.Here,we present new information from the lacustrine sedimentary record in the west...The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain unknown.Here,we present new information from the lacustrine sedimentary record in the western Tibetan Plateau,related to the third most-recent glaciations.Continuous sediment data,including sporopollen,particle size,total organic carbon,mass susceptibility,CaCO_(3),CaSO_(4),BaSO_(4)contents and chronological data,were reconstructed and revealed that climate and environmental conditions obviously and distinctly changed between 600 and 700 thousand years ago.In comparison,the data obtained from the Guliya ice core in this area also corresponds to the global glacial climatic characteristics recorded in basin sediments in the eastern and southeastern regions of the plateau and to the information obtained from ice cores in the Antarctic and Arctic regions.In this study,we conclude that the main reason for the glaciations and new tectonic movement must be a geomagnetic polarity reversal 774 thousand years ago(from Matuyama to Brunhes).Indeed,the results of this study suggest that the described reversal event might have influenced the current global climate pattern and will continue to impact climatic changes in the future.展开更多
基金supported by the National Basic Research Program of China(Grant No.2006CB701406)the National Natural Science Foundation of China(Grant Nos.40672196 and 40638041)+1 种基金the Laboratory of Resources Environment and Management(Grant No.GPMR0520)and the Project 111(Grant No.B07011).
文摘It is generally acknowledged that geomagnetic polarity has reversed many times in geological history and an abnormal geologic phenomenon is the Cretaceous normal superchron. However, the causes have been unknown up to now. The nonlinear theory has been applied to analyze the phenomenon in geomagnetic polarity reversal and the Cretaceous normal superchron. The Cretaceous normal superchron implies that interaction of the Earth's core-mantle and liquid movement in the outer core may be the lowest energy state and the system of Earth magnetic field maintains a sort of temporal or spatial order structure by exchanging substance and energy in the outside continuously. During 121-83 Ma, there was no impact of a celestial body that would result in a geomagnetic polarity reversal, which may be a cause for occurrence of the Cretaceous normal superchron.The randomness of geomagnetic polarity reversal has the self-reversion characteristic of chaos and the chaos theory gives a simple and clear explanation for the dynamic cause of the geomagnetic polarity reversal.
文摘The existing data on the confirmed extraterrestrial impacts and geomagnetic reversals are examined. Differential rotation of the inner core of the Earth relative to the rest of the planet has been observed through seismic records. Differential rotation between the inner and outer core is thought to be related to the geomagnetic field of the Earth. Extraterrestrial impacts with the surface of the Earth have been shown to cause changes in this differential rotation. It is shown in this paper that there is a strong correlation between the dates of major impacts and geomagnetic reversals. This strongly supports the possibility of major extraterrestrial impacts being one of the causes of geomagnetic reversals as has been suggested previously.
文摘The origin of the earth’s magnetic field is one of the five most important unsolved problems in physics, especially geomagnetic polarity reversal remains one of Nature’s most enigmatic phenomena. It is proposed that the geomagnetic polarity reversal links with some global-geology events, although it is difficult to clarify the mechanism of this correlation. The history of continental structures in eastern China would be also linked with some global-geology events.
文摘A statistical model for the quick reversals during a geomagnetic pole transition is put forward by combining the modern geomagnetic field and paleomagnetic field. The decrease of geomagnetic intensity determines the reversals, and the quick reversals are possibly caused by the interaction between g10 and the other geomagnetic components.
文摘The International Geomagnetic Reference Field models (IGRF) for 1900-2000 are used to calculate the geomagnetic field distribution in the Earth' interior from the ground surface to the core-mantle boundary (CMB) under the assumption of insulated mantle. Four reversed polarity patches, as one of the most important features of the CMB field, are revealed. Two patches with +Z polarity (downward) at the southern African and the southern American regions stand out against the background of -Z polarity (upward) in the southern hemisphere, and two patches of -Z polarity at the North Polar and the northern Pacific regions stand out against the +Z background in the northern hemisphere. During the 1900-2000 period the southern African (SAF) patch has quickly drifted westward at a speed of 0.2-0.3°/a; meanwhile its area has expanded 5 times, and the magnetic flux crossing the area has intensified 30 times. On the other hand, other three patches show little if any change during this 100-year period. Extending upward, each of the reversed polarity patches at the CMB forms a chimney-shaped 'reversed polarity column' in the mantle with the bottom at the CMB. The height of the SAF column has grown rapidly from 200km in 1900 to 900km in 2000. If the column grows steadily at the same rate in the future, its top will reach to the ground surface in 600-700 years. And then a reversed polarity patch will be observed at the Earth's surface, which will be an indicator of the beginning of a magnetic field reversal. On the basis of this study, one can describe the process of a geomagnetic polarity reversal, the polarity reversal may be observed firstly in one or several local regions; then the areas of these regions expand, and at the same time, other new reversed polarity regions may appear. Thus several poles may exist during a polarity reversal.
基金supported by grants from the China Geological Survey(Grant Nos.1212010610102,DD20190065).
文摘The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain unknown.Here,we present new information from the lacustrine sedimentary record in the western Tibetan Plateau,related to the third most-recent glaciations.Continuous sediment data,including sporopollen,particle size,total organic carbon,mass susceptibility,CaCO_(3),CaSO_(4),BaSO_(4)contents and chronological data,were reconstructed and revealed that climate and environmental conditions obviously and distinctly changed between 600 and 700 thousand years ago.In comparison,the data obtained from the Guliya ice core in this area also corresponds to the global glacial climatic characteristics recorded in basin sediments in the eastern and southeastern regions of the plateau and to the information obtained from ice cores in the Antarctic and Arctic regions.In this study,we conclude that the main reason for the glaciations and new tectonic movement must be a geomagnetic polarity reversal 774 thousand years ago(from Matuyama to Brunhes).Indeed,the results of this study suggest that the described reversal event might have influenced the current global climate pattern and will continue to impact climatic changes in the future.