Die neuen Arbeiten zur Geologie von Sachsen     

Hans Becker 《International Journal of Earth Sciences》1926,17(5):349-368

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Das Gebiet des Yangtze-Deltas mit den Nanking-Bergen     

Hans Becker 《International Journal of Earth Sciences》1937,28(5):385-406

Ohne Zusammenfassung  相似文献   

The Tamayo transform fault in the mouth of the Gulf of California     

K. A. Kastens  K. C. Macdonald  K. Becker  K. Crane 《Marine Geophysical Researches》1979,4(2):129-151

The Tamayo transform fault is located at the north end of the East Pacific Rise where it enters the Gulf of California. This paper presents bathymetric, seismic reflection, magnetic, and gravity data from a detailed survey of the transform fault. The dominant feature of the offset region is a bathymetric ridge trending 120°, parallel to the predicted transform plate boundary. This transform ridge is associated with a large (600 ) positive magnetic anomaly, and a very small positive free-air gravity anomaly. Magnetic and gravity models indicate either a basalt or serpentinite composition for the ridge, but cannot distinguish between these possibilities. At its eastern end, the modern zone of strike-slip motion is in a narrow valley south of the transform ridge. The transform plate margin appears to pass through a saddle in the transform ridge and meet the western spreading center segment in the trough north of the transform ridge. On the basis of this survey and previous work, the history of the Tamayo from continental breakup to the present has been reconstructed. Initial rifting occurred along a trend of 130° at approximately 3.5 m.y.b.p. Once the transform fault was free of the constraints imposed by continent-continent and continent-oceanic lithospheric interaction, the trend of the transform fault rotated counter-clockwise. This rotation resulted in a leaky transform fault and intrusion of a large continuous transform ridge. Further adjustments in the spreading center/transform fault plate boundary configuration have given rise to an incipient zone of rifting cutting across the transform ridge and emplacement of diapiric structures.Contribution of the Scripps Institution of Oceanography, new series.  相似文献   

Volcanic stratigraphy of DSDP/ODP Hole 395A: An interpretation using well-logging data   总被引：1，自引：0，他引：1  

Bartetzko  Anne  Pezard  Philippe  Goldberg  David  Sun  Yue-Feng  Becker  Keir 《Marine Geophysical Researches》2001,22(2):111-127

Deep Sea Drilling Project/Ocean Drilling Program Hole 395A was drilled approximately 500 m deep into young oceanic crust west of the Mid-Atlantic Ridge. Core recovery is very poor in this hole and therefore continuous downhole measurements are important to understand the drilled lithology. Geophysical downhole measurements were carried out during several cruises. A new set of logs was recorded during Leg 174B in summer 1997. The new logging data show a significant improvement in data quality compared to older measurements from Leg 109. The lithostratigraphy established from cores gives only limited information because of the poor core recovery in this hole. The gaps in the core lithostratigraphy are filled by reconstructing a synthetic lithological profile using the standard well-logging data. Three types of lava morphologies, massive basalts, altered lava flows, and pillow basalts, may be distinguished using the logs because the lava morphologies show differences in their physical properties due to differences in fracturing and alteration. The synthetic lithological profile gives a more detailed and precise vertical definition of single layers than the core profile. The integration of further logging and core data enables a detailed reconstruction of the accretion history at the drill site. Cyclic, upward decreasing trends in the resistivity logs were already observed during earlier cruises and were referred to magmatic cycles. Similar trends occur in the density log and, inversely, in the total gamma ray log. The trends reflect gradual changes in fracturing, porosity, permeability, and alteration and cover depth intervals of several tens of meters. Boundaries between cycles are interpreted to correspond to periods of volcanic quiescence. Two types of boundaries may be identified. Boundaries correlating with reversals in the magnetic field and/or changes in the geochemical composition of the basalts are interpreted as long pauses. Basalts separated by these boundaries were probably fed by separate magma reservoirs. Boundaries identified only by changes in alteration but not in geochemistry are interpreted to represent shorter pauses. They separate basalts that were probably fed by the same magma chamber. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

The contact binary AE phoenicis — An analysis from deconvoluted spectra     

H. J. Becker 《Astrophysics and Space Science》1984,99(1-2):157-161

A method is described for an analysis of deconvoluted stellar spectra, and applied to new spectroscopic observations of the close eclipsing system AE Phuenicis, obtained with the 1.52 m telescope of the Southern European Observatory at La Silla, Chile, Results are presented for the rotational velocities of this variable, together with a proposed model of the system.Paper presented at the Lembang-Bamberg IAU Colloquium No. 80 on Double Stars: Physical Properties and Generic Relations, held at Bandung, Indonesia, 3–7 June, 1983.  相似文献   

The Chan Hol cave near Tulum (Quintana Roo,Mexico): evidence for long‐lasting human presence during the early to middle Holocene          下载免费PDF全文

Fabio Hering  Wolfgang Stinnesbeck  Jens Folmeister  Eberhard Frey  Sarah Stinnesbeck  Jerónimo Avilés  Eugenio Aceves Núñez  Arturo González  Alejandro Terrazas Mata  Martha Elena Benavente  Carmen Rojas  Adriana Velázquez Morlet  Norbert Frank  Patrick Zell  Julia Becker 《第四纪科学杂志》2018,33(4):444-454

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Color imaging of Mars by the High Resolution Imaging Science Experiment (HiRISE)     

W. Alan Delamere  Livio L. Tornabene  Kris Becker  Nathan T. Bridges  Dennis Gallagher  Laszlo Keszthelyi  Guy K. McArthur  Moses Milazzo  Nicolas Thomas 《Icarus》2010,205(1):38-52

HiRISE has been producing a large number of scientifically useful color products of Mars and other planetary objects. The three broad spectral bands, coupled with the highly sensitive 14 bit detectors and time delay integration, enable detection of subtle color differences. The very high spatial resolution of HiRISE can augment the mineralogic interpretations based on multispectral (THEMIS) and hyperspectral datasets (TES, OMEGA and CRISM) and thereby enable detailed geologic and stratigraphic interpretations at meter scales. In addition to providing some examples of color images and their interpretation, we describe the processing techniques used to produce them and note some of the minor artifacts in the output. We also provide an example of how HiRISE color products can be effectively used to expand mineral and lithologic mapping provided by CRISM data products that are backed by other spectral datasets. The utility of high quality color data for understanding geologic processes on Mars has been one of the major successes of HiRISE.  相似文献   

HiRISE observations of gas sublimation-driven activity in Mars’ southern polar regions: I. Erosion of the surface     

C.J. Hansen  N. Thomas  G. Portyankina  A. McEwen  T. Becker  S. Byrne  K. Herkenhoff  H. Kieffer  M. Mellon 《Icarus》2010,205(1):283-295

The High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) has imaged the sublimation of Mars’ seasonal CO₂ polar cap with unprecedented detail for one complete martian southern spring. In some areas of the surface, beneath the conformal coating of seasonal ice, radially-organized channels are connected in spidery patterns. The process of formation of this terrain, erosion by gas from subliming seasonal ice, has no earthly analog. The new capabilities (high resolution, color, and stereo images) of HiRISE enable detailed study of this enigmatic terrain. Two sites are analyzed in detail, one within an area expected to have translucent seasonal CO₂ ice, and the other site outside that region. Stereo anaglyphs show that some channels grow larger as they go uphill - implicating gas rather than liquid as the erosive agent. Dark fans of material from the substrate are observed draped over the seasonal ice, and this material collects in thin to thick layers in the channels, possibly choking off gas flow in subsequent years, resulting in inactive crisscrossing shallow channels. In some areas there are very dense networks of channels with similar width and depth, and fewer fans emerging later in the season are observed. Subtle variations in topography affect the channel morphology. A new terminology is proposed for the wide variety of erosional features observed.  相似文献   

Spectroscopic study of the O-type runaway supergiant HD 195592     

M. De Becker  N. Linder  G. Rauw 《New Astronomy》2010,15(1):76-82

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Die präkambrische Geschichte des Lake Superior-Gebietes,Nordamerika     

Hans Becker 《International Journal of Earth Sciences》1931,22(6):385-411

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