Facies and architectural element analysis of a meandering fluvial succession: The Permian Warchha Sandstone, Salt Range, Pakistan

The 30 to 155 m thick Early Permian (Artinskian) Warchha Sandstone of the Salt Range, Pakistan is a conglomerate, sandstone and claystone succession within which seven lithofacies types (Gt, St, Sp, Sr, Sh, Fl and Fm) occur in a predictable order as repeated fining-upward cycles. Common sedimentary structures in the conglomerates and sandstones include planar and trough cross-bedding, planar lamination, soft sediment-deformed bedding, compound cosets of strata with low-angle inclined bounding surfaces and lags of imbricated pebbles. Structures in the finer-grained facies include desiccation cracks, raindrop imprints, caliche nodules and bioturbation. Groups of associated facies are arranged into nine distinct architectural elements (channels, gravel bars, sandy bedforms, downstream and laterally accreting barforms, sand sheets, crevasse splays, levees, floodplain units and shallow lakes), which is consistent with a fluvial origin for the succession. The types of architectural elements present and their relationship to each other demonstrate that the Warchha Sandstone preserves a record of a meandering river system that drained the northern margin of Gondwanaland. The dominance of fine-grained (floodplain) facies over gravel-grade (channel-base) facies and the widespread occurrence of large-scale lateral accretion elements supports the interpretation of a high-sinuosity, meandering fluvial system in which channel bodies accumulated via the lateral accretion of point bars but in which the active channels covered only a small part of a broad floodplain at any time instant. Although the regional and temporal distribution of these deposits is complex, in broad terms the lower part is dominated by stacked, multistorey channel bodies, whereas single-storey channel elements isolated in abundant fine-grained floodplain deposits dominate the middle and upper parts of the formation.     

The revival of white holes as Small Bangs

Black holes are extremely dense and compact objects from which light cannot escape. There is an overall consensus that black holes exist and many astronomical objects are identified with black holes. White holes were understood as the exact time reversal of black holes, therefore they should continuously throw away material. It is accepted, however, that a persistent ejection of mass leads to gravitational pressure, the formation of a black hole and thus to the “death of while holes”. So far, no astronomical source has been successfully tagged a white hole. The only known white hole is the Big Bang which was instantaneous rather than continuous or long-lasting. We thus suggest that the emergence of a white hole, which we name a ‘Small Bang’, is spontaneous - all the matter is ejected at a single pulse. Thus, unlike black holes, white holes cannot be continuously observed rather their effect can only be detected around the event itself. γ-ray bursts are the most energetic explosions in the universe. Long γ-ray bursts were connected with supernova eruptions. There is a new group of γ-ray bursts, which are relatively close to Earth, but surprisingly lack any supernova emission. We propose identifying these bursts with white holes. White holes seem like the best explanation of γ-ray bursts that appear in voids. We also predict the detection of rare gigantic γ-ray bursts with energies much higher than typically observed.     

矿物白度的影响因素与增白机理研究

白度是矿物的重要光学性质之一。为了深化矿物的光学性质及白色矿物功能材料的研究与应用,根据测试分析结果和叶大年的结构光性矿物学理论,系统研究了影响矿物白度的主要因素,以及矿物增白效果的差异性及其产生机理。研究结果表明:(1)晶体化学是决定不同种类透明矿物白度的最主要因素,但对于某种透明矿物来说,影响其白度的主要因素是矿物中的碳质有机质、含铁钛矿物杂质、杂质元素的价态与晶体化学环境、介质环境、矿物中的水和粒度大小等。(2)证明了透明矿物白度大小与折射率呈正相关。白度相同的不同矿物的增白效果存在很大差异性,其根本原因是由矿物折射率所决定的反射率存在很大差别。(3)提出了真白度和假白度的概念,即主要由自色产生的白度称为真白度,主要由假色产生的白度称为假白度;真白度高的矿物具有增白作用,而真白度低的矿物,即使粉末白度高,也没有增白作用。(4)在影响矿物白度的主要因素中,矿物中的碳质有机质、含铁钛矿物杂质、杂质元素的价态等杂质成分对矿物白度和增白效果起负面作用。(5)矿物中与晶体结构相关的水所产生的颜色属于自色,脱去结晶水、层间水和结构水都有利于提高矿物的真白度或增白效果,但脱去沸石水的效果正好相反;由矿物粒度大小变化产生的颜色属于假色;通过降低粉体粒度大小所提高的白度属于假白度,由此增加的白度没有增白作用。另外,矿物粉体与使用介质之间的折射率大小差别越大,增白效果越明显。     

基于GIS的承德乡村地名文化景观空间分布特征

将承德地区乡村地名作为离散点,以GIS中移动搜索法的点距离空间平滑分析法为支撑,从地理区域这一角度分析地名文化景观空间分布特征。研究发现：承德地区自然类景观,以“山”、“水文”、“动植物”命名的地名分布主要位于中低海拔高度的平坦地区;承德地区乡村地名文化景观划分为军事活动类、经济活动类、房屋建筑类、美愿与纪念类、满蒙少数民族语言及方言类,其空间分布特征与当地历史时期的军事、生产生活、社会变迁的相对频繁程度以及人口稠密情况基本上相符合。     

Looking for a White Male Effect in Generation Z: Race,Gender, and Political Effects on Environmental Concern and Ambivalence

The “White male effect” has been presented in past literature as a way to explain the tendency for White males to have lower environmental concern and risk perceptions than female and non-White individuals. Recently, research has proposed the “White male effect” may be a “conservative White male effect,” due to findings that political ideology impacts environmental concern. This study used a sample of young college-educated adults from Generation Z to test whether the conservative White male effect is present for environmental concern and ambivalence toward a proenvironmental worldview in this younger generation. Online surveys were distributed to undergraduate students at a large northeastern university in spring of 2016. A total of 1,940 surveys were returned. Results showed a lack of a unique White male, or conservative White male, effect above and beyond differences explained by gender, Whiteness, and political affiliation. The implications of this effect’s absence are discussed.     

Inferring Glacier Mass Balance Using Radarsat: Results From Peyto Glacier, Canada

The capability of RADARSAT synthetic aperture radar (SAR) for the purpose of snow-line/accumulation area mapping for a temperate alpine glacier is examined. In agreement with other orbital C-band SAR studies, RADARSAT can discriminate between firn and bare ice facies. Limited observations are reported with respect to the electromagnetic variability of the ice facies in the ablation area, but they are inconclusive. Operational considerations are discussed with respect to reconciling the uncertainties of late-summer weather and their possible impact on the dielectric and scattering properties of the glacier surface. Vagaries associated with other glacier settings, mass balance states and their associated facies configurations are discussed including the difficulty of using the transient snow-line to define the equilibrium line and the lower extent of the accumulation area for glaciers where superimposed ice may form.
The radar remote-sensing reconnaissance of equilibrium line altitude (ELA) and accumulation area ratio (AAR) for estimating glacier mass balance requires serious consideration in those instances where traditional ground measurements used in the direct glaciological method are absent. However, with respect to the ELA, such estimates can vary depending on the accuracy of the reference digital elevation information. Moreover, for many glacier configurations, where mass balance variations due to altitude are influenced or in some cases completely masked by local balance variations, defining the ELA may be an irreconcilable problem. Using the AAR may be more robust in this regard. It is further determined that the total error inherent in the reconnaissance method would have serious implications for the confident estimation of mass balance normals and climate-related trends if the method were to be utilized over the longer term.     

Annual Mass Balance of Blue Glacier, USA: 1955–97

Mass changes of Blue Glacier, USA are calculated from topographic maps made from vertical aerial photography in late summer of 1939, 1952, 1957, and 1987, along with laser altimetry flown in June 1996. Changes in elevation between maps were adjusted for seasonal variations in the snow cover, and to account for the ablation between the date of photography and 1 October. Topography obtained from the laser altimetry was adjusted for snow thickness and glacier motion to estimate topography of 1 October 1995. The mass of Blue Glacier has changed less than 7 m (water equivalent) during this 56 year period which is minor compared with other glaciers in the region and elsewhere in the world. Glacier-average annual mass balances, beginning in 1956, have been calculated either from stake measurements and probing of late-season snow, or from a regression analysis using late-season measurements of the equilibrium line altitude. A comparison with the changes derived from surface maps shows values obtained from field measurements are too positive by about 0.4 m a^?1 , indicating that considerable caution is needed when interpreting time series of mass balance. Two alternative time series of mass balance consistent with the long-term mass changes are created by making simple adjustments: (1) a single constant is subtracted from each value so that the series is consistent with the 1957–95 mass change; (2) one constant is subtracted from each value over 1957–87 and another is subtracted from each value over 1987-95 so that the series is consistent with both the 1957–87 and 1987–95 mass changes. The mass balance of Blue Glacier was generally positive until the mid-1970s and negative since. The fluctuations of mass balance closely resemble those of snowfall on the glacier as estimated from the joint distribution of temperature and precipitation. The climate in western Washington was cooler and wetter during the decade before the mid-1970s, but the trend since has been towards warmer and drier conditions.     

Analysis of Winter and Summer Glacier Mass Balances

Seasonal mass balance components b_w (winter balance) and b_s (summer balance) as well as c_t (total accumulation) and a_t (total ablation), can be used directly to infer climate variables. In contrast, a_c (net balance of the accumulation area) and a_a (net balance of the ablation area), and b_a or b_n (annual or net balance) can not. The traditional Alpine system of observations of a_c and a_a , however, can be converted to true seasonal values b_w and b_s if both pairs of components are simultaneously observed for some years, because a correlation between the two pairs of components exists. We analyzed b_w and b_s data and their mean, standard deviations and ratios of these to the corresponding net or annual balances for 50 glaciers with relatively long records representing different regions in the northern hemisphere. We also investigated correlations between seasonal components. A negative correlation between b_w and b_s exists at many glaciers. About two-thirds of the glaciers show insignificant correlations (?0.3 < r < 0.3), implying independence of summer and winter balances. In a few unusual cases the correlations are positive. These different correlations, or lack thereof, may offer insight into feedback conditions that must exist in this climate-related system. The correspondence of the b_w and c_t , and b_s and a_t , appears to depend largely on the relative amounts of summer snowfall, a function of their climatic environment expressed as [α = (b_w+b_s)/2]. The contribution of variability of b_s to the net balance increases markedly with decreasing values of α. The variability of b_w and b_s , and therefore the net balance, has been increasing with time; whether this is due to an increase in climate variability or to other causes is not clear. It appears that b_w has been increasing with time at the highest altitudes, but b_s has been increasing more rapidly especially at low altitudes; the many-glacier average net balance is becoming more negative.     

基于知识的点状符号自动识别

文中根据地形图黑版要素中点状符号的特点,总结了6种易于表达的知识特征,并据此提出了一种基于知识的点状符号识别方法。     

基于ArcGIS点抽稀的河南省灾情速报骨干网建设

河南省地震局灾情速报员队伍经过多年建设,目前在册灾情速报员多达3万余人,数量位居全国前列,但也存在灾情速报员数量过多、管理不易等问题,为确保河南省地震灾情速报员队伍发挥作用,以河南省现有行政村点为基础,根据空间均匀分布的原则,以5×6 km为格网单元,对ArcGIS的三种不同的点抽稀方法进行对比分析,最终选择SubsetFeatures和SubPoints相结合的方法,提取出6000多个行政村点,依此为依据报送人员名单,以保证每个乡(镇、街道办事处)有3～5名灾情速报人员组成河南省骨干灾情速报员队伍,从而强化灾情速报工作管理。