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171.
In this 8th compilation, the following results of observations are given: 207 observed minima of 56 eclipsing binaries, 100 maxima of 21 RR Lyrae- and δ Cephei-stars, 82 results of 32 Mira stars and long period variables, and 47 results of 9 RV Tauri stars, semiregular, and irregular variables, from the years 1966 up to 1968.  相似文献   
172.
Ordovician sediments at Tagoat and Rosslare Harbour are re-described and their relationship to the underlying Rosslare Series discussed. A brief outline of their petrology is given, but it is shown that the fauna is in need of revision before reliable correlations can be made. Similar rocks are recorded near Tomhaggard; amongst these, spotted mudstones imply Ordovician or later intrusions. Undeformec dykes intrusive into the Rosslare Series are believed to be representatives of this phase.  相似文献   
173.
174.
The Potato River intrusion is a Keweenawan (1100 Ma) mafic plutonemplaced in Keweenawan volcanics and earlier Proterozoic metasedimentaryrocks along the southeastern flank of the Lake Superior syncline.It comprises the following lithostratigraphic zones: a thinto absent Border zone of altered olivine gabbro; a Lower zoneof olivine gabbro; a Picritic zone of picrite and troctolite;a Middle zone of olivine gabbro and leucogabbro; an Upper zoneof quartz leucogabbro and ferrogabbro; and a Roof zone of granophyricand granitic rocks. Fractional crystallization is evident fromcompositional changes in the rocks and cumulus minerals withstratigraphic height. Elements concentrated in the cumulus mineralsolivine and plagioclase (Mg, Fe2+, Al, Ca, Ni, Co, Cr, Sr) decreasewith height; elements concentrated in the trapped liquid (Na,K, La, Y, Zr, Nb, Rb, Ba) increase with height; and other elements(Ti, Fe3+, P, Ga, V, Sc, Cu, Zn) show complicated behavior relatedto the appearance of additional cumulus phases such as clinopyroxene,Fe-Ti oxides, and apatite. Lower zone rocks contain some sulfide,probably from sulfur derived from the country rock, and theUpper zone has sulfides probably precipitated from an immisciblesulfide liquid. The sulfide-bearing rocks have similaritiesto those of other intrusions, such as Bushveld, Stillwater,and Skaergaard. The picritic and troctolitic rocks of the Picritic zone indicatethat the intrusion was open to additional injections of maficmagma. Roof zone granophyric rocks are residual liquids intrudedalong the upper margin of the intrusion during regional tilting,but Roof zone granitic rocks are probably melted country rock.An attempt is made to estimate by reverse stratigraphic summationthe compositional path of the magma that solidified above thePicritic zone. The first compositions are highly aluminous,which suggests that the upper part of the intrusion has beenenriched in plagioclase by convection-aided crystal sorting.A complementary unit of mafic rocks is not exposed, but it couldbe present down dip. Some of the later compositions are similarto typical Keweenawan high-Al tholeiites. The magma did notundergo extreme iron enrichment, probably because of oxygenfugacity buffering.  相似文献   
175.
Carbon and oxygen isotopes were determined on 40 recrystallized shells of Late Jurassic bivalves from the Lusitanian Basin of Portugal. In contrast with the oxygen isotopes, which exhibited considerable diagenetic distortion, the carbon isotopes are thought to preserve a record of the salinity of the Jurassic marginal marine seas in which these bivalves lived. The reconstructed palaeosalinities range from 35%o (euhaline) to 5% (oligohaline). Comparing these values with the palaeosalinity reconstructed from a palaeoecological analysis of 17 stratigraphic levels within the basin, the independently derived values agree in most cases. Strongly differing values are explained as being due to biotic factors and to diagenetic distortion of the isotopic signal; they are less likely to be due to smallscale time-averaging or insufficient microstratigraphic sampling. On the whole, the carbon isotope analyses are thought to produce reasonable palaeosalinity values, although data from infaunal, originally aragonitic bivalves appear to be less reliable than those from epifaunal bivalves with a predominantly or exclusively calcitic shell. As diagenetic alteration of the carbon isotope signal is, however, unpredictable and biotic effects on the isotopic composition are insufficiently known, palaeosalinity reconstructions based on stable isotope data should be supported by palaeoecological data.  相似文献   
176.
The specimens studied were collected by Mr.C.T.Wang (王景尊)from Yuehfangkou (月房溝),a locality at about 1500 m.SW of Shangpei-chuan (上白泉) village,the latter at about 45 km west of Chiaocheng city.  相似文献   
177.
In a short paper entitled "Evidences of the Use of Fire by Sinanthropus",Dr.Davidson Black has discussed the occurrence of burned bone fragments andcharcoal debris in association with the remains of Sinanthropus at Chou KouTien,and has concluded that Sina  相似文献   
178.
基于三角形网格的气象场等值线自动分析   总被引:2,自引:3,他引:2  
针对矩形网格法的不足,提出了用三角形网格法实现气象场等值线自动分析方法。通过对站点资料的边界插值、三角形剖分等处理后,再在剖分出来的三角形网格中按照一定方式连接等值线即可实现等值线的自动分析。给出了等值线自动生成算法,并将实例的分析结果同Grads绘制图进行对比分析。结果表明,该方法不仅有效可行,而且分析的结果更为精确合理。  相似文献   
179.
云南省Internet网络天气预报会商系统   总被引:1,自引:0,他引:1  
黄玮  李蒙  王月庆  陈坚  王灵 《气象》2004,30(10):52-55
云南省基于Internet网络的天气预报会商系统覆盖云南省、地 (州 )、县三级。系统采用了Internet网络技术、数据库技术 ,实现了省、地 (州 )、县天气预报发布及浏览查询、预报讨论BBS、天气预报会商室、系统管理 ,在线短消息互发等功能。  相似文献   
180.
Changes in temperature and precipitation extremes in the CMIP5 ensemble   总被引:5,自引:1,他引:5  
Twenty-year temperature and precipitation extremes and their projected future changes are evaluated in an ensemble of climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5), updating a similar study based on the CMIP3 ensemble. The projected changes are documented for three radiative forcing scenarios. The performance of the CMIP5 models in simulating 20-year temperature and precipitation extremes is comparable to that of the CMIP3 ensemble. The models simulate late 20th century warm extremes reasonably well, compared to estimates from reanalyses. The model discrepancies in simulating cold extremes are generally larger than those for warm extremes. Simulated late 20th century precipitation extremes are plausible in the extratropics but uncertainty in extreme precipitation in the tropics and subtropics remains very large, both in the models and the observationally-constrained datasets. Consistent with CMIP3 results, CMIP5 cold extremes generally warm faster than warm extremes, mainly in regions where snow and sea-ice retreat with global warming. There are tropical and subtropical regions where warming rates of warm extremes exceed those of cold extremes. Relative changes in the intensity of precipitation extremes generally exceed relative changes in annual mean precipitation. The corresponding waiting times for late 20th century extreme precipitation events are reduced almost everywhere, except for a few subtropical regions. The CMIP5 planetary sensitivity in extreme precipitation is about 6 %/°C, with generally lower values over extratropical land.  相似文献   
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