Book review     

Petr Jakeš  Marck Wolf 《Earth, Moon, and Planets》1995,71(1-2):175-176

  相似文献   

Seasat altimeter sensor file algorithms     

Hancock  D. Forsythe  R. Lorell  J. 《Oceanic Engineering, IEEE Journal of》1980,5(2):93-99

The Seasat altimeter is designed to measure three parameters important to oceanography: height of the spacecraft above the ocean surface (h), significant wave height (H_{1/3}), and ocean backscatter coefficient (sigmadeg) from which surface winds may be inferred. Since the measurement process is indirect, and the measurement environment is complicated by many factors affecting the instrument readings, corrections to the raw data are needed before they are used to compute geophysical parameters. These corrections are accomplished by the Seasat altimeter sensor file algorithms. The purpose of this paper is to describe these algorithms, why they are needed, how they are implemented, and their evaluation using in-flight data.  相似文献   

Elimination of directional wave spectrum contamination from noise in elevation measurements     

Walsh  E. Hancock  D.  III Hines  D. Swift  R. Scott  J. 《Oceanic Engineering, IEEE Journal of》1985,10(4):376-381

The Surface Contour Radar (SCR) is a 36-GHz computer-controlled airborne radar which generates a false-color-coded elevation map of the sea surface below the aircraft in real time, and can routinely produce ocean directional wave spectra with post-flight data processing which have much higher angular resolution than pitch-and-roll buoys. The SCR range measurements are not error-free and the resulting errors in the elevations corrupt the directional wave spectrum. This paper presents a technique for eliminating that contamination.  相似文献   

The interaction between hydrology and geomorphology in a landscape simulator experiment     

Greg Hancock  Garry Willgoose 《水文研究》2001,15(1):115-133

An experimental landscape simulator has been developed which uses a rainfall simulator to create overland flow and erosion. The simulator uses rainfall sprinklers that eliminate rainsplash and an artificial soil which has little cohesion. Experimental landscapes developed in the simulator evolved according to Howard's headward growth model. Elements of Glock's model could be identified during evolution (i.e. initiation and maximum extension), but other stages of this model were not observed (i.e. extension and integration). The Horton concept of cross‐grading and micropiracy and stream piracy was not observed despite the dominance of overland flow, nor the groundwater headward growth mechanism proposed by Dunne, the latter due to experimental design, which eliminated any perched groundwater table. The experimental apparatus produced model landscapes that are scaled‐down analogues of real world processes. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

Late quaternary stratigraphy and geochemistry of the R47 section,Rouge River Basin,south-central Ontario,Canada: Correlation with Scarborough Bluffs     

W. C. Mahaney  R. G. V. Hancock Slowpoke 《第四纪科学杂志》1993,8(2):167-178

Quaternary glacial diamictons in section R47, overlying Ordovician shale in the Rouge River Basin of south-central Ontario, are considered to be representative of older and younger Wisconsinan glacial diamictons in the field area. Field characteristics, clast composition, mineralogy, particle size and geochemistry permit delineation of two units within the sequence and subdivision of deposits that correlate with Sunnybrook and Halton diamictons of Wisconsinan age. No Wisconsinan interstadial deposits are present in the section; however, outwash sandy gravel capping the Halton diamicton was probably emplaced by a high-energy stream draining into Lake Iroquois just prior to the incision of the Rouge Valley in the later Wisconsinan (ca. 11 000-12 000 yr BP). A buried palaeosol, which developed in this sandy gravel and in overlying aeolian sediment, shows partial leaching of carbonates and a slight increase of clay in the palaeosol solum. The main clay-mineral transformations in the buried palaeosol appear to involve the degradation of illite and illite-smectite accompanied by the production of vermiculite and minor amounts of chlorite. The ground soil capping the buried palaeosol is formed in colluvium emplaced 200 ± 80 yr BP following a local forest fire; the ground soil Ahk horizon gives an age of 4000 yr in the future, probably as a result of nuclear bomb testing effects on modern radiocarbon. The presence of an A/C profile in the ground soil system, although thin, indicates that surface soils may form rapidly. The geochemistry of the two Wisconsinan diamictons shows similar calcite and SiO₂-corrected mean element concentrations, with slightly elevated levels of Ca, Sr, Hf and Lu in the younger deposit. Both diamictons are geochemically quite different from the shale bedrock in the area, indicating that the bulk of transported sediment came from outside the area.  相似文献   

Formation of patterned ground and fine-scale soil development within two late Holocene glacial chronosequences: Jotunheimen, Norway     

Jake E. Haugland   《Geomorphology》2004,61(3-4):287-301

Chronosequences of 250 to 130 years were established on two late Holocene glacier forelands in the Jotunheimen region of southern Norway. Patterned features occurring within chronologically established time units were studied. Young patterned features, forming 10–20 years after deglaciation, are frost active. Vegetation cover is minimal within the young patterned features, consisting of bryophytes/organic crusts. Soil development within patterned ground is also minimal/absent because frost action retards horizonization. With time and distance from the glaciated ice margin, frost activity declines within the patterned features, suggesting that a thin, active “periglacial zone” exists near the ice margin. Initially, frost activity decreases at the borders of the features with the centers stabilizing later in time. This results in fine-scale soil heterogeneity and variations of soil development. Fine-scale pedogenic development is first encountered at the borders of patterned ground that has developed on terrain exposed since the 1930s, yet soil development is predominantly absent at the centers of patterned ground. With time and distance from the ice margin, frost activity declines and allows patterned features to homogenize from border to center positions in regard to soil characteristics. Across the chronosequences, soils within patterned features pedogenically follow previous soil chronosequence studies, evolving from USDA classifications of Entisols into Inceptisols. Frost disturbance within patterned ground, however, produces a lag effect, that results in longer periods of time for pedogenesis to occur and thinner soils than that of the surrounding terrain.  相似文献   

The production of digital elevation models for experimental model landscapes     

Greg Hancock  Garry Willgoose 《地球表面变化过程与地形》2001,26(5):475-490

Automated digital photogrammetry was used to produce digital elevation models of experimental model landscapes under controlled laboratory conditions as part of a series of rainfall erosion experiments looking at the evolution of landforms in response to erosion. The method allowed the elevations of the experimental landscapes to be studied in great detail on a regular grid digital terrain map with relatively very little effort. Digital photogrammetry produced elevation data at a resolution of 6 mm with a standard deviation of 2·0 mm over an experimental catchment relief of approximately 200 mm; this resolution is considerably better than that achievable by conventional manual photogrammetry. The density of grid points was sufficiently high that small‐scale details such as knickpoints developing in channels were represented. The method can facilitate the study of both experimental and natural landscapes in great detail. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

Wenlock stratigraphy and palaeogeography of Wales and the Welsh Borderland     

J.M. Hurst  N.J. Hancock  W.S. McKerrow 《Proceedings of the Geologists' Association. Geologists' Association》1978,89(3):197-226

  相似文献   

Predicting earthquakes: Wyss,M. (editor) 1979. Earthquake Prediction and Seismicity Patterns. Contributions to Current Research in Geophysics,No. 8, Birkhauser,Basel. 238 pp. Price: hard-cover sFr68, DM72, US $45.     

P.L. Hancock 《Journal of Structural Geology》1980,2(4):470-471

  相似文献   

Referees for volume 1     

Paul Hancock  Tony Barber 《Journal of Structural Geology》1979,1(4):345

  相似文献