Pioneering U-Pb isotopic studies by a small group of workers in the mid-late 1980s demonstrated the feasibility of using rare accessory mineral chronometers in mafic(gabbroic)intrusive rocks.These examples showed that...Pioneering U-Pb isotopic studies by a small group of workers in the mid-late 1980s demonstrated the feasibility of using rare accessory mineral chronometers in mafic(gabbroic)intrusive rocks.These examples showed that mafic layered intrusions and diabase/dolerite dyke swarms alike crystallized high-temperature展开更多
The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Ear...The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life （Fig. 1）. It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event （GOE） at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon （the so-called Neoproterozoic Oxidation Event or NOE） was responsible for the diversification of metazoans （Lyons et al., 2014）.展开更多
In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 ...In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12) of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 1720 km, or the density decreased from 14200 km/m3 (2.57 times the present density) to 5520 kg/m3 within the latest 4.3 billion years.展开更多
The astronomical theory of climate change is based on the solution of differential equations describing Earth’s orbital and rotational motions. The equations are used to calculate the change in insolation over the Ea...The astronomical theory of climate change is based on the solution of differential equations describing Earth’s orbital and rotational motions. The equations are used to calculate the change in insolation over the Earth’s surface. As a result of the author’s solution of the orbital problem, the periods and amplitudes of Earth-orbit variations and their evolution have been refined. Unlike previous studies, the equations of Earth’s rotational motion are solved completely. The Earth’s rotational axis precesses relative to a direction different from the direction of the orbit’s axial precession, and oscillates with periods of half a month, half a year and 18.6 years. Also, its oscillations occur with irregular periods of several tens of thousands of years and more. All these motions lead to oscillations of the obliquity in the range of 14.7° to 32.1°, which prove to be 7 - 8 times larger than obtained by a previous theory. In the same proportion, the Earth’s insolation oscillations increase in amplitude, with insolation extremes occurring in other epochs than those in the previous theory. The amplitudes and the onset times of the extremes correlate with known paleoclimate changes. Thirteen insolation periods of paleoclimate variation over an interval of 200 thousand years are identified. From the insolation evolution calculated over a time interval of 1 million years, 6 climate gradations from very cold to very warm are identified.展开更多
文摘Pioneering U-Pb isotopic studies by a small group of workers in the mid-late 1980s demonstrated the feasibility of using rare accessory mineral chronometers in mafic(gabbroic)intrusive rocks.These examples showed that mafic layered intrusions and diabase/dolerite dyke swarms alike crystallized high-temperature
文摘The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life （Fig. 1）. It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event （GOE） at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon （the so-called Neoproterozoic Oxidation Event or NOE） was responsible for the diversification of metazoans （Lyons et al., 2014）.
基金the National Natural Science Foundation of China (Grant No. 49774236),
文摘In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12) of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 1720 km, or the density decreased from 14200 km/m3 (2.57 times the present density) to 5520 kg/m3 within the latest 4.3 billion years.
文摘The astronomical theory of climate change is based on the solution of differential equations describing Earth’s orbital and rotational motions. The equations are used to calculate the change in insolation over the Earth’s surface. As a result of the author’s solution of the orbital problem, the periods and amplitudes of Earth-orbit variations and their evolution have been refined. Unlike previous studies, the equations of Earth’s rotational motion are solved completely. The Earth’s rotational axis precesses relative to a direction different from the direction of the orbit’s axial precession, and oscillates with periods of half a month, half a year and 18.6 years. Also, its oscillations occur with irregular periods of several tens of thousands of years and more. All these motions lead to oscillations of the obliquity in the range of 14.7° to 32.1°, which prove to be 7 - 8 times larger than obtained by a previous theory. In the same proportion, the Earth’s insolation oscillations increase in amplitude, with insolation extremes occurring in other epochs than those in the previous theory. The amplitudes and the onset times of the extremes correlate with known paleoclimate changes. Thirteen insolation periods of paleoclimate variation over an interval of 200 thousand years are identified. From the insolation evolution calculated over a time interval of 1 million years, 6 climate gradations from very cold to very warm are identified.
