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Electron microprobe data on phosphide grains detected for the first time in basalts from volcanic edifices in the Sea of Japan are presented. The find of phosphides can testify to the endogenic source of phosphorus and, consequently, volcanogenic hydrothermal origin of phosphorites in the Sea of Japan. 相似文献
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Postnikov A. V. Postnikova O. V. Iz”yurova E. S. Poshibaev V. V. Kuznetsov A. S. Iz”yuraov A. D. Kozionov A. E. 《Lithology and Mineral Resources》2019,54(1):27-37
Lithology and Mineral Resources - Main regularities in the manifestation of epigenetic processes in Lower Vendian terrigenous rocks of the Nepa–Botuoba anteclise are established. Evolution of... 相似文献
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Vitit Kantabutra J. B. “Jack” Owens Daniel P. Ames Charles N. Burns Barbara Stephenson 《Transactions in GIS》2010,14(Z1):39-58
This article introduces a type of DBMS called the Intentionally‐Linked Entities (ILE) DBMS for use as the basis for temporal and historical Geographical Information Systems. ILE represents each entity in a database only once, thereby mostly eliminating redundancy and fragmentation, two major problems in Relational and other database systems. These advantages of ILE are realized by using relationship objects and pointers to implement all of the relationships among data entities in a native fashion using dynamically‐allocated linked data structures. ILE can be considered to be a modern and extended implementation of the E/R data model. ILE also facilitates storage of things that are more faithful to the historical records, such as gazetteer entries of places with imprecisely known or unknown locations. This is difficult in Relational database systems but is a routine task using ILE because ILE is implemented using modern memory allocation techniques. We use the China Historical GIS (CHGIS) and other databases to illustrate the advantages of ILE. This is accomplished by modeling these databases in ILE and comparing them to the existing Relational implementations. 相似文献
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David “Jim” Nemeth 《The Professional geographer》2013,65(4):583-586
Why is Ortley Beach, New Jersey, known as Superstorm Sandy's ground zero? This article employs qualitative vulnerability analysis to understand why vulnerability of second homes in Ortley Beach resulted in dune failure and slow rebuilding after Sandy. The second-home owners who largely make up the community in Ortley Beach are identified as the key vulnerable group. This group's lack of political representation and financial compensation after Sandy increased house damage and slowed rebuilding. Identifying the level of vulnerability of the majority group in a location is paramount to understanding how the community recovers from a disaster. Such identification can also aid in preparing communities, especially for types of disasters they have not yet encountered. 相似文献
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We monitored the concentrations of copper, lead and cadmium in seawater, in suspended particulate matter (SPM) and in bacteria, phyto- and zooplankton communities separated from abiogenic particles, over a one year cycle in two coupled Mediterranean coastal ecosystems (Little Bay (LiB) and Large Bay (LaB)). Metals were present in seawater in the order Cu > Pb > Cd in both bays and showed important variations within the same month than among months. In LiB, their concentrations were between 0.62 and 2.82 μg Cu l−1, 0.16 and 19 μg Pb l−1 and 0.007 and 0.14 μg Cd l−1, respectively, whereas in LaB, they were between 0.23 and 2.11 μg Cu l−1, 0.09 and 0.76 μg Pb l−1 and not detected and 0.65 μg Cd l−1. SPM play an important role on metal adsorption, especially for copper. Bioaccumulation factors showed that bacteria and phytoplankton accumulate metals whereas zooplankton tends to biodiminish them in the plankton food web. 相似文献
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Shapes on a plane: evaluating the impact of projection distortion on spatial binning 总被引：1，自引：0，他引：1
ABSTRACTOne method for working with large, dense sets of spatial point data is to aggregate the measure of the data into polygonal containers, such as political boundaries, or into regular spatial bins such as triangles, squares, or hexagons. When mapping these aggregations, the map projection must inevitably distort relationships. This distortion can impact the reader’s ability to compare count and density measures across the map. Spatial binning, particularly via hexagons, is becoming a popular technique for displaying aggregate measures of point data sets. Increasingly, we see questionable use of the technique without attendant discussion of its hazards. In this work, we discuss when and why spatial binning works and how mapmakers can better understand the limitations caused by distortion from projecting to the plane. We introduce equations for evaluating distortion’s impact on one common projection (Web Mercator) and discuss how the methods used generalize to other projections. While we focus on hexagonal binning, these same considerations affect spatial bins of any shape, and more generally, any analysis of geographic data performed in planar space. 相似文献
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Kondrat'eva I. A. Maksimova I. G. Nad”yarnykh G. I. 《Lithology and Mineral Resources》2004,39(4):333-344
Application of f-radiography for the study of ore-bearing rocks of the Malinov uranium deposit revealed the following specific features: (1) occurrence of uranium in both authigenic and terrigenous components; (2) important role of fine–dispersed (mineral-free) mode of uranium occurrence; and (3) participation of different-aged epigenetic processes in the ore formation. The sequence of ore formation and transformation in this deposit is similar to that in the Semizbai deposit. Therefore, they can be united into a single subtype of Mesozoic infiltration deposits in western Siberia. 相似文献
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An adaptable equal-area pseudoconic map projection 总被引：1，自引：1，他引：0
Daniel “daan” Strebe 《制图学和地理信息科学》2016,43(4):338-345
Equivalence (the equal-area property of a map projection) is important to some categories of maps. However, unlike conformal projections, completely general techniques do not exist for creating new, computationally reasonable equal-area projections. The literature describes many specific equal-area projections and a few equal-area projections that are more or less configurable, but flexibility is still sparse. This work describes a new, highly configurable equal-area projection system consisting of arcs of concentric circles, placing it in the pseudoconic class. The system uses a novel technique to hybridize the Bonne pseudoconic projection and the Albers conic projection, subsuming many existing projections as degenerate cases. With the resulting system and the technique used to develop it, map projection designers will have greater choice in tailoring the projection to the need. The system may be particularly suited to maps that dynamically adapt to changing scale and region of interest, such as required for online maps. 相似文献