Geochemistry and petrogenesis of the marginal zone of the Mount Lowe Intrusion,central San Gabriel Mountains,California     

Andrew P. Barth  Perry L. Ehlig 《Contributions to Mineralogy and Petrology》1988,100(2):192-204

The marginal zone of the Mount Lowe Intrusion (MLI) is composed of a mineralogically and geochemically distinctive suite of quartz poor, alkali-enriched monzodiorites and quartz monzodiorites. Low initial ⁸⁷Sr/⁸⁶Sr, Rb, and Rb/Sr coupled with high Ab/Or, K/Rb, Ba and Sr suggest that feldspathic continental crust did not contribute significantly to the magma. The inferred original magma composition is most consistent with experimental data for about 20% batch modal melting of eclogite or quartz eclogite of altered oceanic tholeiite composition. The high absolute Ba and Sr abundances require in addition an enriched component, perhaps derived from dehydration processes within a subducted slab. At the level of exposure, the range of observed compositions resulted from fractionation of hornblende, plagioclase, sphene, apatite and magnetite. Fractionation resulted in formation of a peraluminous, Mn — enriched residual liquid which crystallized garnet. The grandite — enriched composition of the garnet is inferred to be due to high pressure (ca. 6.7 kb), high crystallization, relative to typical plutonic garnets. The composition of the marginal zone of MLI has many chemical similarities to early Mesozoic plutonism in the Cordilleran continental margin magmatic arc of western North America.  相似文献   

Desertification processes and impacts in irrigated regions     

R. A. Perry 《Climatic change》1986,9(1-2):43-47

Desertification in irrigated regions is caused by man's activities but may be more rapid in periods of drought or abnormally high rainfall. It is caused by sedimentation of canals, use of poor quality water, or waterlogging or salinization because of rising groundwater tables caused by excessive applications of irrigation water. It can be avoided by good land management in catchments and irrigation areas but social, economic, and political factors cause difficulties. Direct costs due to loss of production from affected lands are less than indirect costs to national economies.  相似文献   

Book reviews     

Vecchione  Michael  Maples  Robert  Williams  Austin B.  Anderson  Franz E.  Herrgesell  Perry L. 《Estuaries and Coasts》1984,7(3):265-268

Estuaries and Coasts -  相似文献   

IV. Water resource modelling using remote sensing and object-oriented simulation     

Harlan L. McKim  E. Alan Cassell  Perry J. Lapotin 《水文研究》1993,7(2):153-165

Remote sensing technology has matured significantly over the past decade. Operational satellites provide reliable, periodic coverage for all areas of the Earth. Data from these satellites are in a digital format that provides enhanced flexibility in hydrological modelling. Considerable advances in acquiring hydrological data from airborne and in situ sensors have also been achieved. Additionally, data from non-traditional remote sources such as weather radar from which spatial and temporal rainfall rates may be estimated are widely available. These new data acquisition capabilities have been paralleled by equal advancements in digital array processing and geographic information systems, which allow the effective extraction of both temporal and spatial information. This paper examines the use of object-oriented programming techniques to create dynamic hydrological models, and explores their potential to receive real and near real-time data from remote sensors as input to improve hydrological forecasting. In particular, the COE SSARR model is used to illustrate how an established hydrological model may be adapted to create a dynamic object model.  相似文献   

THE SINGAPORE GROWTH TRIANGLE: STATE,CAPITAL AND LABOUR AT A NEW FRONTIER IN THE WORLD ECONOMY     

Martin Perry Ph.D. 《Singapore journal of tropical geography》1991,12(2):138-151

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On determining the electron density distribution of the solar corona from K-coronameter data     

Martin D. Altschuler  R. Michael Perry 《Solar physics》1972,23(2):410-428

The electron density distribution of the inner solar corona (r 2 R ) as a function of latitude, longitude, and radial distance is determined from K-coronameter polarization-brightness (pB) data. A Legendre polynomial is assumed for the electron density distribution, and the coefficients of the polynomial are determined by a least-mean-square regression analysis of several days of pB-data. The calculated electron density distribution is then mapped as a function of latitude and longitude. The method is particularly useful in determining the longitudinal extent of coronal streamers and enhancements and in resolving coronal features whose projections on the plane of the sky overlap.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   

BUSINESS CLUSTERS IN THE SOUTH: A CRITICAL APPRAISAL FROM INDONESIAN EVIDENCE     

Martin Perry 《Singapore journal of tropical geography》2005,26(2):227-243

Advocacy of the advantages accruing to business clusters in developing economies has followed that in developed economies. With doubts emerging about the evidence for these in developed economies, it is therefore appropriate to review the experience in the developing world. A model of cluster emergence and growth has guided accounts of developing country clusters. Drawing on experience from Indonesia, doubts are raised about that model's prediction of the emergence of successful joint action in maintaining cluster advantages. Any advantages from clustering are insufficient to face development challenges arising from the globalisation of economic activity. The significance of business clusters in low income economies needs to be reviewed in the light of actual experience and the reappraisal emerging in developed or high income countries.  相似文献   

Oceanic–atmospheric modes of variability and their influence on riverine input to coastal Louisiana and Mississippi     

Guillermo Sanchez-Rubio  Harriet M. Perry  Patricia M. Biesiot  Donald R. Johnson  Romuald N. Lipcius 《Journal of Hydrology》2011,396(1-2):72-81

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Export and mesopelagic particle flux during a North Atlantic spring diatom bloom   总被引：2，自引：0，他引：2  

Patrick Martin  Richard S. LampittMary Jane Perry  Richard SandersCraig Lee  Eric D'Asaro 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(4):338-349

Spring diatom blooms are important for sequestering atmospheric CO₂ below the permanent thermocline in the form of particulate organic carbon (POC). We measured downward POC flux during a sub-polar North Atlantic spring bloom at 100 m using thorium-234 (²³⁴Th) disequilibria, and below 100 m using neutrally buoyant drifting sediment traps. The cruise followed a Lagrangian float, and a pronounced diatom bloom occurred in a 600 km² area around the float. Particle flux was low during the first three weeks of the bloom, between 10 and 30 mg POC m⁻² d⁻¹. Then, nearly 20 days after the bloom had started, export as diagnosed from ²³⁴Th rose to 360-620 mg POC m⁻² d⁻¹, co-incident with silicate depletion in the surface mixed layer. Sediment traps at 600 and 750 m depth collected 160 and 150 mg POC m⁻² d⁻¹, with a settled volume of particles of 1000-1500 mL m⁻² d⁻¹. This implies that 25-43% of the 100 m POC export sank below 750 m. The sinking particles were ungrazed diatom aggregates that contained transparent exopolymer particles (TEP). We conclude that diatom blooms can lead to substantial particle export that is transferred efficiently through the mesopelagic. We also present an improved method of calibrating the Alcian Blue solution against Gum Xanthan for TEP measurements.  相似文献   

A lightweight vertical rosette for deployment in ice-covered waters     

William M. Smethie Jr.  Dale ChayesRichard Perry  Peter Schlosser 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(4):460-467

A lightweight modular rosette system has been developed that can be launched and recovered from aircraft in ice-covered waters through a 12 in. diameter hole in the ice. The small diameter is achieved by the modular design, in which a CTD module is attached to the end of a conducting cable and water bottle modules (four 4-L bottles per module) are positioned vertically above it. A novel tripping mechanism based on melting a link of monofilament line is used to close the water bottles at the desired depths. After launching the rosette, the cast proceeds like a normal rosette cast with the traces of temperature, salinity, oxygen and other desired sensors being displayed on a computer screen during the down and up casts and tripping the bottles electronically at the desired depths on the up cast. A Seabird 19+ CTD and Seabird 43 oxygen sensor are mounted in the CTD module and data acquisition and bottle tripping are controlled using a Seabird 33 deck unit and Seabird's SeaSave software run on a laptop computer. Deployment and recovery are done in a heated tent attached to the aircraft to prevent the water from freezing. After recovery the bottle modules are placed in coolers with bags of snow to stabilize the cooler temperature close to 0 °C, which is within ±1.8 °C of the in situ temperature, and the modules are transported back to a base camp for subsampling and sample processing. This system has been used to collect over 250 water samples in the ice-covered Lincoln Sea and the quality of the samples for dissolved gases and other constituents has been excellent.  相似文献