A GIS method to identify flat surfaces and restore relict fluvial long-profiles from terrace remnants gives new clues on how large basins respond to endorheic–exorheic transitions (Duero basin,Iberian Peninsula)     

Laura Rodríguez-Rodríguez  Loreto Antón  Raimon Pallàs  Daniel García-Castellanos  Ivone Jiménez-Munt  Candela Pastor-Martín 《地球表面变化过程与地形》2020,45(4):1013-1027

Fluvial terraces are used as geomorphic indicators for deciphering long-term landscape evolution. Knowing the distribution of fluvial terraces is essential for establishing former river profiles and their tectonic significance, for studying climate-modulated processes of terrace development, or for defining fluvial network adjustments in response to sudden base-level changes like those produced by fluvial captures. Multiple methods for automatic map production have been proposed based on the comparison of morphometric indices with those of the modern river course. Here we propose an alternative method to identify flat surfaces and scarps separating them from digital elevation models without setting comparisons with a modern river course and thus fully applicable to study flat landforms whatever their origin. Its application to the low-relief landscape of the Cenozoic Duero basin has allowed the improvement of previous geomorphological maps and the analysis of fluvial network adjustments in response to a sudden base-level fall after the opening of the Neogene endorheic basin towards the Atlantic Ocean. Reconstructed terrace long-profiles suggest an initial episode of fast vertical incision followed by a period of repeated planation–aggradation–incision with the formation of 14 to 13 unpaired terrace levels. Changes observed in the pattern of terrace profiles are discussed with regard to changes in regional tectonics and base-level variations. © 2019 John Wiley & Sons, Ltd.  相似文献   

Trends in groundwater quality     

Jim C. Loftis 《水文研究》1996,10(2):335-355

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Rethinking Poisson-Based Statistics for Ground Water Quality Monitoring     

Jim C. Loftis  Hariharan K. Iyer  Heather J. Baker 《Ground water》1999,37(2):275-281

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有限元法在滑坡稳定性分析中的应用   总被引：5，自引：0，他引：5  

詹军  于清杨 《煤田地质与勘探》2002,30(1):45-47

对比了滑坡稳定性分析的极限平衡法、数值分析法、概率法。而后,介绍了有限元法滑坡稳定性分析基本原理,并应用有限元法对中里滑坡进行了稳定性分析,得出了中里滑坡的主应力图和稳定系数,并将稳定系数与其他方法的结果进行了比较,得出有限元法是一种可靠的分析方法,其结果可应用于后期治理设计。   相似文献   

The origin of epigenetic graphite: evidence from isotopes   总被引：1，自引：0，他引：1  

Paul L Weis  Irving Friedman  Jim P Gleason 《Geochimica et cosmochimica acta》1981,45(12):2325-2332

Stable carbon isotope ratios measured in syngenetic graphite, epigenetic graphite, and graphitic marble suggests that syngenetic graphite forms only by the metamorphism of carbonaceous detritus. Metamorphism of calcareous rocks with carbonaceous detritus is accompanied by an exchange of carbon between the two, which may result in large changes in isotopic composition of the non-carbonate phase but does not affect the relative proportions of the two reactants in the rock. Epigenetic graphite forms only from carbonaceous material or preexisting graphite. The reactions involved are the water gas reaction (C + H₂O → CO + H₂) at 800–900°C, and the Boudouard reaction (2CO → C + CO₂), which probably takes place at temperatures about 50–100°C lower.  相似文献   

Inexpensive Access Tube Installation of Tensiometers Below a Flowing Stream     

Laurel J. Lacher  Thomas Maddock III  T.-C. Jim Yeh 《Ground Water Monitoring & Remediation》1997,17(3):76-77

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A Structured Approach for Calibrating Steady-State Ground-Water Flow Models     

T.-C. Jim Yeh  Peter A. Mock 《Ground water》1996,34(3):444-450

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Book reviews     

Michael Webber  Phillip M. O'Neill  Gordon L. Clark  Philip S. Morrison  D. R. Scott  Jim Whitelaw 《The Australian geographer》1991,22(2):185-196

THE CAPITALIST SPACE ECONOMY: Geographical Analysis after Ricardo, Marx and Sraffa by E. Sheppard and T. J. Barnes. 15 × 22 cm, xviii and 328 pages. Unwin Hyman: London 1990 (ISBN 004 330401 X) £40.00 hard; (ISBN 004 330402 8) £14.95 (soft).

THE INTERNATIONAL STEEL INDUSTRY: Restructuring, State Policies and Localities by R. Hudson and D. Sadler. 14 × 22 cm, xii and 163 pages. Routledge: London 1989 (ISBN 0 415 02186 3) $A89.95 (hard).

INDUSTRIAL TRANSFORMATION AND CHALLENGE IN AUSTRALIA AND CANADA (Carleton Library No. 164) edited by R. Hayter and P. D. White. 15 × 23 cm, x and 340 pages. Carleton University Press: Ottawa 1990 (ISBN 0 88629 129 1) $A34.95 (hard); (ISBN 0 88629 128 3) $A 19.95 (soft).

LABOUR MIGRATION. The Internal Geographical Mobility of Labour in the Developed World edited by J. H. Johnson and J. Salt. 15 × 24 cm, viii and 215 pages. David Fulton: London 1990 (ISBN 1 85346 120 2) £30.00 (hard).

CITIES IN SPACE: CITY AS PLACE by D. Herbert and C. Thomas. 15 × 23 cm, xi and 340 pages. David Fulton: London 1990 (ISBN 1 85346 138 5) £35.00 (hard); (ISBN 1 85346 109 1) £14.95 (soft).

THE NEW URBAN FRONTIER. Urbanisation and City Building in Australasia and the American West by L. Frost. 15 × 23 cm, xvii and 226 pages. New South Wales University Press: Sydney (ISBN 0 86840 268 0) $A24.95 (soft).

SYDNEY: A Social Atlas by R. Horvath, G. E. Harrison and R. M. Dowling. 19 × 28 cm, 110 pages. Sydney University Press: Sydney 1989 (ISBN 0 424 00144 6) $A19.95 (soft).

CHANGE AND ADJUSTMENT IN NORTHERN NEW SOUTH WALES edited by D. J. Walmsley. 17 × 23 cm. 118 pages. Department of Geography and Planning, University of New England: Armidale 1990 (ISBN 0 85834 887 X) $A10.00 (soft).

ANNOTATED BIBLIOGRAPHY OF URANIUM IN AUSTRALIA (Cover Title: URANIUM IN AUSTRALIA 1970–1987: An Annotated Bibliography) by C. O'Faircheallaigh, A. Webb and D. Wade‐Marshall. 18 × 25 cm, xi and 306 pages. North Australia Research Unit, Australian National University: Darwin 1989 (ISBN 07315 05433).  相似文献   

Assessment of toxicological status of a SW Mediterranean segment population of striped dolphin (Stenella coeruleoalba) using skin biopsy     

Fossi MC  Marsili L  Lauriano G  Fortuna C  Canese S  Ancora S  Leonzio C  Romeo T  Merino R  Abad E  Jiménez B 《Marine environmental research》2004,58(2-5):269-274

Various studies have revealed high concentrations of contaminants such as organochlorines (OCs) and heavy metals in Mediterranean cetaceans. A geographical trend of contamination (PCBs and DDTs) has been found for striped dolphin (Stenella coeruleoalba). In this study we used a non-lethal approach (skin biopsy) to investigate bioaccumulation of OCs, including polychlorobiphenyls (PCBs), DDTs, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), trace elements (Hg, Cd, Pb) and CYP1A activity (BPMO) in nine striped dolphins sampled in the Aeolian area (Sicily - Italy) in summer 2002. The arithmetic mean value of BPMO activity in this group was 43.46 AUF/g tissue/h. This value is approximately 3 times and 5 times lower, respectively, than the value found in the Ionian and in the Ligurian groups. Skin biopsies of striped dolphins emerged as a suitable material for assessing the toxicological status of the various Mediterranean groups.  相似文献   

Searching behaviour and catch of horse mackerel (Trachurus murphyi) by industrial purse-seiners off south-central Chile   总被引：2，自引：0，他引：2  

Hancock  Jim; Hart  Paul J. B.; Antezana  Tarcisio 《ICES Journal of Marine Science》1995,52(6):991-1004

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