Book review: Water Wells and Boreholes, by Bruce Misstear, David Banks and Lewis Clark (John Wiley & Sons, 2006)     

Rick Brassington 《Hydrogeology Journal》2011,19(5):1115-1116

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Climate change in Lake Baikal: diatom evidence in an area of continuous sedimentation     

M. Bangs  R. W. Battarbee  R. J. Flower  D. Jewson  J. A. Lees  M. Sturm  E. G. Vologina  A. W. Mackay 《International Journal of Earth Sciences》2000,89(2):251-259

The presence of inhomogeneous sedimentation is acknowledged as being an important problem in palaeolimnological studies. Sediment records can be disturbed by erosional and redepositional events, which redeposit microfossils within a basin and may then lead to misinterpretations of fossil diatom assemblages. This study uses a combination of sedimentological tools, magnetic susceptibility measurements and high-resolution diatom analysis to show that a sediment core, BAIK80, taken in 345 m water depth from a shoulder region in the North Basin of Lake Baikal, is free of disturbances. Our results confirm that the sediment record is consistent and continuous for the uppermost sediment. Consequently, the fossil diatom data can be used to establish a continuous record of past climate variability over approximately the past 1300 years. Distinct changes occur in downcore abundances of endemic taxa Aulacoseira baicalensis and Cyclotella minuta, and principal components analysis (PCA) indicates a gradual transformation of taxa over the past 1300 years. These changes are likely to be related to climate, although definite links still have to be established. Received: 15 December 1998 / Accepted: 13 September 1999  相似文献   

Carbon cycling in the German Bight: An estimate of transformation processes and transport     

A. Reimer  S. Brasse  R. Doerffer  C. -D. Dürselen  S. Kempe  W. Michaelis  H. -J. Rick  R. Seifert 《Ocean Dynamics》1999,51(2-3):313-329

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Conversion of nutrients in the Elbe river plume during drift experiments in the German Bight during spring 1995 and summer 1994     

U. Brockmann  K. Viehweger  T. Raabe  S. Rick  H. -J. Rick  R. Heller  D. TopÇu 《Ocean Dynamics》1999,51(2-3):293-312

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Fluorescent Dyes: A New Weapon for Conquering DNAPL Characterization          下载免费PDF全文

John Horst  Nicklaus Welty  Robert Stuetzle  Rick Wenzel  Randy St. Germain 《Ground Water Monitoring & Remediation》2018,38(1):19-25

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On the Relevance of $$\ln (z_{0} /z_{0T})= kB^{-1}$$     

Bruce B. Hicks  William R. Pendergrass  Barry D. Baker  Rick D. Saylor  Debra L. O’Dell  Neal S. Eash  Jeffrey T. McQueen 《Boundary-Layer Meteorology》2018,167(2):285-301

The assumption that the roughness Reynolds number \(( Re_{*})\) can be used as a basis for quantifying the boundary-layer property \({ kB}^{-1} (= \ln (z_{0}/z_{0T}))\) as in some modern numerical models is questioned. While \({ Re}_{*}\) is a useful property in studies of pipe flow, it appears to have only marginal applicability in the case of treeless terrain, as studied in the two experimental situations presented here. For both the daytime and night-time cases there appears to be little correlation between \({ kB}^{-1}\) and \({ Re}_{*}\). For daytime, the present studies indicate that the assumption \({ kB}^{-1} \approx 2\) is acceptable, while for night-time, the scatter involved in relating \({ kB}^{-1}\) to \({ Re}_{*}\) suggests there is little reason to assume a direct relationship. However, while the scatter affecting all of the night-time results is large, there remains a significant correlation between the heat and momentum fluxes upon which an alternative methodology for describing bulk air–surface exchange at night could be constructed. The friction coefficient (\(C_{f}\)) and the turbulent Stanton number \(({ St}_{*})\) are discussed as possible alternatives for describing bulk properties of the air layer adjacent to the surface. While describing the surface roughness in terms of the friction coefficient provides an attractive simplification relative to the conventional methodologies based on roughness length and stability considerations, use of the Stanton number shares many of uncertainties that affect \({ kB}^{-1}\). The transitions at dawn and dusk remain demanding situations to address.  相似文献   

Headless submarine canyons and fluid flow on the toe of the Cascadia accretionary complex   总被引：1，自引：0，他引：1  

Daniel L. Orange  Brian G. McAdoo  J. Casey Moore  Harold Tobin  Elizabeth Screaton  Hank Chezar  Homa Lee  Mark Reid  & Rick Vail 《Basin Research》1997,9(4):303-312

Headless submarine canyons with steep headwalls and shallowly sloping floors occur on both the second and third landward vergent anticlines on the toe of the Cascadia accretionary complex off central Oregon (45 °N, 125° 30′W). In September 1993, we carried out a series of nine deep tow camera sled runs and nine ALVIN dives to examine the relationship between fluid venting, structure and canyon formation. We studied four canyons on the second and third landward vergent anticlines, as well as the apparently unfailed intercanyon regions along strike. All evidence of fluid expulsion is associated with the canyons; we found no evidence of fluid flow between canyons. Even though all fluid seeps are related to canyons, we did not find seeps in all canyons, and the location of the seeps within the canyons differed. On the landward facing limb of the second landward vergent anticline a robust cold seep community occurs at the canyon’s inflection point. This seep is characterized by chemosynthetic vent clams, tube worms and extensive authigenic carbonate. Fluids for this seep may utilize high-permeability flow paths either parallel to bedding within the second thrust ridge or along the underlying thrust fault before leaking into the overriding section. Two seaward facing canyons on the third anticlinal ridge have vent clam communities near the canyon mouths at approximately the intersection between the anticlinal ridge and the adjacent forearc basin. No seeps were found along strike at the intersection of the slope basin and anticlinal ridge. We infer that the lack of seepage along strike and the presence of seeps in canyons may be related to fluid flow below the forearc basin/slope unconformity (overpressured by the impinging thrust fault to the west?) directed toward canyons at the surface.  相似文献   

Modelling discard ogives from Irish demersal fisheries     

Borges  Lisa; Zuur  Alain F.; Rogan  Emer; Officer  Rick 《ICES Journal of Marine Science》2006,63(6):1086-1095

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A controlling factor approach to estuary classification     

Terry M. Hume  Ton Snelder  Mark Weatherhead  Rick Liefting 《Ocean & Coastal Management》2007,50(11-12):905-929

A new approach to the classification of estuaries is described. The estuary environment classification (EEC) is based on a hierarchical view of the abiotic components that comprise the environments of estuaries. The EEC postulates that climate, oceanic, riverine and catchment factors ‘control’ a hierarchy of processes and broadly determine the physical and biological characteristics of estuaries. The classification differentiates estuaries at four levels of detail. Level 1 differentiates global scale variation based on differences in climatic and oceanic processes, which are discriminated by the factors: latitude, oceanic basins and large landmasses. Level 2 differentiates variation in estuary hydrodynamic processes, which are discriminated by estuary basin morphometry, river and oceanic forcing. Level 3 differentiates variation among estuaries that are due to catchment processes, which are discriminated by catchment geology and catchment land cover. The approach has been applied to all the estuaries in New Zealand using existing data sources. Estuaries were assigned class membership at each level of the classification by applying criteria in the form of decision rules to the database of assignment characteristics. GIS was then used to map the estuaries with classes being defined by colour at any level of the classification. The resulting map provides a multi-scale spatial framework that is suitable for many environmental or conservation management applications.  相似文献   

Hamilton's principle and the vorticity laws for a relativistic perfect fluid     

Rick Salmon 《地球物理与天体物理流体动力学》2013,107(2):167-179

Abstract

The equations for a relativistic perfect fluid result from the requirement that the total mass-energy be stationary with respect to variations δx^α(a, b, c, s) in the space-time location of the fluid particle identified by Lagrangian labels (a, b, c) at the point s on its world-line. By considering variations of the Lagrangian labels that leave the specific volume and entropy unchanged, we obtain a general covariant statement of vorticity conservation. The conservation laws for circulation, potential vorticity, and helicity are simple corollaries. This Noether-theorem derivation shows that the vorticity laws have no analogues in particle mechanics, where the corresponding particle labels cannot be continuously vaned.  相似文献