Mafic Dykes in Rauer Islands and Vestfold Hills (East Antartica): A Geochemical and Nd Isotopic Comparison Arguing Against Their Correlation

正Mafic dykes have been long considered possible tectonostratigraphic markers in East Antarctica because they are largely confined to Archaean–Early Proterozoic cratonic blocks but are absent from mid-to late Proterozoic or     

重新评估新马德里地震带

以新马德里地震带(以下简称NMSZ，图1)而知名的美国大陆中部地区，尽管远离板块边界，但却频繁发生特大地震，其发震机制一直是个未解之谜。NMSZ地区并没有大多数活动形变地区构造运动特征的显著地形起伏，但当面对该整个地区地震危险性在某些概率水平上可以与旧金山湾地区相比的证据时，我们多数人感到需要“拧自已一下以看看我们是否在做梦”。尽管在很多方面，评估NMSZ地区的危险性比评价美国西部地区更具挑战性，不确定性更大，但经过细致地科学研究，已经在地震危险性评估的最关键问题上达成了共识。[这里给出的一致性看法反映了美国地质调查局和美国中部地震中心(一个由国家科学基金会资助的大学协会组织)2000年1月主办的一次讨论会上与会的二十几位科学家在会上及会后在国际互联网和专业会议上公开发表的一些看法。]     

CORRESPONDENCE ANALYSIS AND ADSORBATE SELECTION FOR CHEMICAL SENSOR ARRAYS

Carey et al.utilized principal components analysis (PCA) to analyze frequency shift data obtained frompiezoelectric sensors formed by coating quartz crystals with 27 different GC stationary phases and testedusing 14 analytes.The objective of the analysis was to determine an optimal reduced set of coatings fordetection of the analytes.The results were correlated with those obtained from cluster analysis.In thispaper the data are re-analyzed using correspondence analysis (CA).The advantage of using CA includea symmetric treatment of sensor coatings and analytes and better identification of the representation ofthe analytes in terms of the detection components.The results obtained by the conjunctive use of PCA,a varimax rotation and cluster analysis were obtained by CA.     

根据长期树木年轮记录再现美国大平原的干旱

1、引言近百年内,美国大平原普遍发生的几次干旱造成农业崩溃,引起经济危机。其中十九世纪90年代、二十世纪30年代和50年代的干旱最引人注目。严重干旱重现的经验概率对研究水资源和农业生产规划很有意义。但目前的降水资料不能描绘十九世纪以前的干旱史。近来的研究证明了利用树木年轮资料延长区域干旱历史的实用性。这些研究仅是个别州的干旱,范围较小。     

EAST ASIA MARGINAL BASINS SEDIMEN-TOGENESIS FEATURES

The alternations of sedimentogenic and asedimentogenic belts on the continental shelf and slope are distinctive features in the East Asia marginal basins.These sedimentogenesis characteristics areconditioned by the terrigenous material supply and their distribution patterns. Facial analysis of the marginal basins reveals a number of typical facial models which are comparablewith the geosynclinal and subplatform formations of the ancient basins. The paragenetical situation and simultaneous coexistence of these facial models in the modern margi-nal seas indicate that the ancient formation could be deposited in the same way,at the same time andeven in the same basin.     

RANK-ORDER ANALYSIS FOR ROBUST MULTIRESPONSE,MULTIBLOCK COMPARISONS:EVALUATION OF HERBICIDE INTERACTIONS

Studies of interactions among bioactive compounds are often difficult to interpret unambiguously.A priori assumptions about the nature of such interactions can seriously distort analysis of the data.Byapplying a rank order analysis appropriate to the naturally ordinal scale of response to xenobiotic insult,several co-herbicides were successfully identified from among numerous candidates in an experimentinvolving multiple blocks,rates and species.Moreover,underlying herbicide interactions weresubstantiated and identified which were not apparent by more traditional parametric analysis.