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布青山蛇绿混杂岩位于阿尼玛卿带西段，它是由早古生代和早石炭世一早二叠世两期蛇绿岩组成的复合蛇绿混杂岩带。蛇绿岩中的变质橄榄岩以方辉橄榄为主，高镁，∑PEE是球粒陨石的0．2－0．65倍，HREE是球粒陨石的0．28－0．32倍，属亏损的大洋岩石圈地幔。早古生代蛇绿岩中辉长岩、辉绿岩和玄武岩等镁铁质岩主要具N－MORB性质，少量具T－MORB性质。早石炭世一早二叠世蛇绿岩中玄武岩也主要具N－MORB性质、少量具T－MORB性质。它们均形成于洋中脊环境。本区曾存在成熟的早古生代洋盆和古特提斯洋盆，有更复杂的构造演化史。 相似文献
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Gary Latham Maurice Ewing James Dorman Yosio Nakamura Frank Press Nafi Toksőz George Sutton Fred Duennebier David Lammlein 《Earth, Moon, and Planets》1973,7(3-4):396-421
Analysis of seismic signals from man-made impacts, moonquakes, and meteoroid impacts has established the presence of a lunar crust, approximately 60 km thick in the region of the Apollo seismic network; an underlying zone of nearly constant seismic velocity extending to a depth of about 1000 km, referred to as the mantle; and a lunar core, beginning at a depth of about 1000 km, in which shear waves are highly attenuated suggesting the presence of appreciable melting. Seismic velocitites in the crust reach 7 km s–1 beneath the lower-velocity surface zone. This velocity corresponds to that expected for the gabbroic anorthosites found to predominate in the highlands, suggesting that rock of this composition is the major constituent of the lunar crust. The upper mantle velocity of about 8 km s–1 for compressional waves corresponds to those of terrestrial olivines, pyroxenites and peridotites. The deep zone of melting may simply represent the depth at which solidus temperatures are exceeded in the lower mantle. If a silicate interior is assumed, as seems most plausible, minimum temperatures of between 1450°C and 1600°C at a depth of 1000 km are implied. The generation of deep moonquakes, which appear to be concentrated in a zone between 600 km and 1000 km deep, may now be explained as a consequence of the presence of fluids which facilitate dislocation. The preliminary estimate of meteoroid flux, based upon the statistics of seismic signals recorded from lunar impacts, is between one and three orders of magnitude lower than previous estimates from Earth-based measurements.Paper dedicated to Professor Harold C. Urey on the occasion of his 80th birthday on 29 April, 1973. 相似文献
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Frank Press 《地震地质》2000,22(2):103
我想根据自己的经历回顾过去 4 0年来美国科学的发展 ,我有幸在这个时期中成长为一名地球物理学家。这个时期被称为科学的黄金时代 ,因为在基础科学和工程科学中有大量发现和进展。在这个时期 ,不仅有伟大的创造和充足的资金支持 ,还获得了很多新知识 ,正是这些知识产生了新的工业并使我们增加了对环境的理解。对于地球物理学 ,正是在这个时期使用现代技术对海底进行了勘测 ,建立了全球地震台网 ,用实验室实验模拟深部地球环境 ,将示踪元素化学应用于岩石系统。也是在这个时期 ,对其它行星做了探测并从月球取回了岩样 ,创立了板块构造理论。在其它领域也有巨大进展 ,如分子生物学与疾病性质研究 ,以及农业绿色革命等。许多科学家在开始自己的研究时 ,并未想到后来会有那么多的创效益应用。许多年轻的科学家不珍惜美国科学尤其是地球物理学的繁荣。在四十年代以前 ,美国有较强的技术和工业生产优势 ,但在科学方面不如西欧 ,类似于现在的日本。那时基础研究主要在得到私人慈善机构支持的大学以及少数政府机构和工业实验室中进行。例如州立大学和地质调查局承担了地质填图 ,一些石油公司实验室开拓了勘探地球物理。除了地学外 ,政府对基础科学的资助很少。那时世 相似文献
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Seismic data from the Apollo Passive Seismic Network stations are analyzed to determine the velocity structure and to infer the composition and physical properties of the lunar interior. Data from artificial impacts (S-IVB booster and LM ascent stage) cover a distance range of 70–1100 km. Travel times and amplitudes, as well as theoretical seismograms, are used to derive a velocity model for the outer 150 km of the Moon. TheP wave velocity model confirms our earlier report of a lunar crust in the eastern part of Oceanus Procellarum.The crust is about 60 km thick and may consist of two layers in the mare regions. Possible values for theP-wave velocity in the uppermost mantle are between 7.7 km s–1 and 9.0 km s–1. The 9 km s–1 velocity cannot extend below a depth of about 100 km and must decrease below this depth. The elastic properties of the deep interior as inferred from the seismograms of natural events (meteoroid impacts and moonquakes) occurring at great distance indicate that there is an increase in attenuation and a possible decrease of velocity at depths below about 1000 km. This verifies the high temperatures calculated for the deep lunar interior by thermal history models.Paper presented at the Lunar Science Institute Conference on Geophysical and Geochemical Exploration of the Moon and Planets, January 10–12, 1973. 相似文献
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Moonquakes and lunar tectonism 总被引：1，自引：0，他引：1
Gary Latham Maurice Ewing James Dorman David Lammlein Frank Press Naft Toksőz George Sutton Fred Duennebier Yosio Nakamura 《Earth, Moon, and Planets》1972,4(3-4):373-382
With the succesful installation of a geophysical station at Hadley Rille, on July 31, 1971, on the Apollo 15 mission, and the continued operation of stations 12 and 14 approximately 1100 km SW, the Apollo program for the first time achieved a network of seismic stations on the lunar surface. A network of at least three stations is essential for the location of natural events on the Moon. Thus, the establishment of this network was one of the most important milestones in the geophysical exploration of the Moon. The major discoveries that have resulted to date from the analysis of seismic data from this network can be summarized as follows:
- Lunar seismic signals differ greatly from typical terrestrial seismic signals. It now appears that this can be explained almost entirely by the presence of a thin dry, heterogeneous layer which blankets the Moon to a probable depth of few km with a maximum possible depth of about 20 km. Seismic waves are highly scattered in this zone. Seismic wave propagation within the lunar interior, below the scattering zone, is highly efficient. As a result, it is probable that meteoroid impact signals are being received from the entire lunar surface.
- The Moon possesses a crust and a mantle, at least in the region of the Apollo 12 and 14 stations. The thickness of the crust is between 55 and 70 km and may consist of two layers. The contrast in elastic properties of the rocks which comprise these major structural units is at least as great as that which exists between the crust and mantle of the earth. (See Toks?zet al., p. 490, for further discussion of seismic evidence of a lunar crust.)
- Natural lunar events detected by the Apollo seismic network are moonquakes and meteoroid impacts. The average rate of release of seismic energy from moonquakes is far below that of the Earth. Although present data do not permit a completely unambiguous interpretation, the best solution obtainable places the most active moonquake focus at a depth of 800 km; slightly deeper than any known earthquake. These moonquakes occur in monthly cycles; triggered by lunar tides. There are at least 10 zones within which the repeating moonquakes originate.
- In addition to the repeating moonquakes, moonquake ‘swarms’ have been discovered. During periods of swarm activity, events may occur as frequently as one event every two hours over intervals lasting several days. The source of these swarms is unknown at present. The occurrence of moonquake swarms also appears to be related to lunar tides; although, it is too soon to be certain of this point.
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A. Rob MacKenzie Stefan Krause Kris M. Hart Richard M. Thomas Phillip J. Blaen R. Liz Hamilton Giulio Curioni Susan E. Quick Angeliki Kourmouli David M. Hannah Sophie A. Comer-Warner Nicolai Brekenfeld Sami Ullah Malcolm C. Press 《水文研究》2021,35(3):e14096
The ecosystem services provided by forests modulate runoff generation processes, nutrient cycling and water and energy exchange between soils, vegetation and atmosphere. Increasing atmospheric CO2 affects many linked aspects of forest and catchment function in ways we do not adequately understand. Global levels of atmospheric CO2 will be around 40% higher in 2050 than current levels, yet estimates of how water and solute fluxes in forested catchments will respond to increased CO2 are highly uncertain. The Free Air CO2 Enrichment (FACE) facility of the University of Birmingham's Institute of Forest Research (BIFoR) is the only FACE in mature deciduous forest. The site specializes in fundamental studies of the response of whole ecosystem patches of mature, deciduous, temperate woodland to elevated CO2 (eCO2). Here, we describe a dataset of hydrological parameters – seven weather parameters at each of three heights and four locations, shallow soil moisture and temperature, stream hydrology and CO2 enrichment – retrieved at high frequency from the BIFoR FACE catchment. 相似文献
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I.M. Gelfand Sh.A. Guberman V.I. Keilis-Borok L. Knopoff F. Press E.Ya. Ranzman I.M. Rotwain A.M. Sadovsky 《Physics of the Earth and Planetary Interiors》1976,11(3):227-283
A pattern recognition procedure is explained which uses geological data and the earthquake history of a region, in this case California, and learns how to separate earthquake epicenters from other places. Sites of future earthquake epicenters are predicted as well as places where epicenters will not occur. The problem is formulated in several ways and control experiments are devised and applied in order to test the stability of the procedures and engender confidence in the results. Some of the combinations of geological features which the computer recognized as significant discriminants are discussed. 相似文献
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Don Aldiss Helen Burke Barrie Chacksfield Richard Bingley Norman Teferle Simon Williams David Blackman Richard Burren Nigel Press 《Proceedings of the Geologists' Association. Geologists' Association》2014
Long term planning for flood risk management in coastal areas requires timely and reliable information on changes in land and sea levels. A high resolution map of current changes in land levels in the London and Thames estuary area has been generated by satellite-based persistent scatterer interferometry (PSI), aligned to absolute gravity (AG) and global positioning system (GPS) measurements. This map has been qualitatively validated by geological interpretation, which demonstrates a variety of controlling influences on the rates of land level change, ranging from near-surface to deep-seated mechanisms and from less than a decade to more than 100,000 years’ duration. 相似文献