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71.
Abstract

Innovations for the British Army during World War I included use of a military geologist to compile 'water supply' maps and to guide well drilling. Between June 1915 and November 1918, W. B. R. King served as a staff lieutenant at General Headquarters of the British Expeditionary Force deployed on the Western Front. He pioneered British development of water supply maps for parts of Belgium and northern France, in several different styles and at scales of 1 : 100 000, 1 : 250 000 and 1 : 40 000. These assisted planning for advances into enemy-occupied territory or the development of water supply infrastructure within the region held ultimately by five British armies: in total about 1,500,000 men with some 500,000 horses and mules, each man/animal requiring on average 10 gallons (45 L) per day of potable water. The maps guided emplacement of over 470 military boreholes to supply drinking water to British forces, especially in provinces underlain by Cretaceous Chalk: Picardy and Artois. German forces also made use of military geologists at the Front, but in much greater number: up to about 300 in total. Water supply tasks were given high priority, and German water supply maps were finally standardized like other medium scale German geotechnical maps at 1 : 25 000. Six geologists were deployed with the American Expeditionary Force late in the war, and for their sector of the Front compiled at least two water supply maps at 1 : 80 000, and 11 at 1 : 50 000 that were supported by explanatory reports. Wartime imperatives thus generated expertise in hydrogeology that became available for civilian use post-war, and laid the foundation for further military development during World War II.  相似文献   
72.
ABSTRACT

During Palestine Campaign of World War I, the British Army’s Egyptian Expeditionary Force produced a series of operation maps to track and control the progress of their offensive into Palestine. These maps demonstrated innovation in both their form and function, and they have been referenced and reproduced by both map scholars and military historians ever since. Leaning on J.B. Harley and Matthew Edney’s ideas about critical map history, this essay provides a critical examination of these operation maps to illuminate the sociocultural context of their creation and examines the maps’ influence over the broader historiography of the Palestine Campaign. In doing so it highlights the interdisciplinary value of critical map histories.  相似文献   
73.
Ulmus carpinifolia tree leaves were successfully used to remove Tl(I) from aqueous solution in a batch system. In order to improve the uptake capacity of sorbent, it was modified by various chemical agents such as NaOH, HNO3, NH3, NaCl, NaHCO3, and CaCl2. Among the modifiers, NaCl was the best. Equilibrium behavior of sorbent with Tl(I) was examined by the several isotherms. Considering modified U. carpinifolia equilibrium data fitted well to the Langmuir model with maximum capacity of 54.6 mg/g. The other isotherms such as: Freundlich and Dubinin‐Redushkevich (D‐R) models were also examined. The central composite design (CCD) was successfully employed for optimization of biosorption process. An empirical model was given through using response surface methodology. Also its validation was recognized by using relevant statistical tests such as ANOVA. The optimum conditions of biosorption: pH, m (amount of sorbent) and C (initial concentration) were found to be 7.9, 11.4 g/L, and 8.8 mg/L, respectively. On the other hand thermodynamic parameters: ΔG, ΔH, and ΔS were evaluated: the obtained results show that biosorption process was spontaneous and exothermic. Eventually, FT‐IR analysis confirmed that the main functional groups of sorbent have been involved through the biosorption process.  相似文献   
74.
DSQ水管仪和SSQ-2I水平摆效能对比研究   总被引:1,自引:1,他引:0  
SSQ-2I型水平摆仪器和DSQ水管仪同属倾斜类前兆仪器,两者观测原理不同,但观测物理量一致.相对于水管仪而言,SSQ-2I型水平摆属于新型仪器,有关其运行效能的评价很少.延庆地震台从2007年开始两种仪器同场地观测,通过年变幅度、滤波残差、周期分析、Venedikov调和分析、相关性分析、抗干扰能力等角度,对两种仪器...  相似文献   
75.
Eight lacustrine Type I kerogen samples from the Songliao Basin were pyrolyzed using the Rock-Eval equipment, and parallel first-order reaction models including the model with a single frequency factor and a discrete distribution of activation energies (SFF model) and the model with multiple frequency factors and a discrete distribution of activation energies (MFF model) were adopted to analyze kinetic characteristics of hydrocarbon generation of the Type I kerogen samples. The results show that the MFF and SFF models can satisfactory simulate hydrocarbon generation under laboratory conditions and the Type I kerogen shows relatively concentrated activation energy distributions (activation energies of MFF model range from 190 kJ/mol to 250 kJ/mol, activation energies of SFF model range from 220 kJ/mol to 240 kJ/mol), which indicates a homogeneous chemical bond structure of the Type I kerogen. The hydrocarbon generated curves from Type I kerogen were calculated by using the two models with a linear heating rate (3.3 K/Ma). It indicates that the hydrocarbon generation potentials (reaction fractions) are underestimated by using the SFF model during the kerogen thermal degradation for the components with chemical bond of lower and higher activation energies, while this problem can be avoided by using the MFF model. The calculated temperatures for 50% transformation ratio (TR) of all samples differ by as much as 20 °C. For the SFF model, the hydrocarbon generation curve obtained by using the weighted averaged kinetic parameters and the SFF model almost includes every curve calculated by using its own kinetic parameters. While the curve obtained by using the weighted averaged kinetic parameters and the MFF model cannot include every curve for all samples, it lies at the position of the averaged curve of all samples. The application of the MFF model in Songliao Basin shows that if TR 10% is taken as the onset of hydrocarbon generation, the threshold depth of hydrocarbon generation is about 1700 m, which is consistent with other geochemical parameters, such as S1/TOC, S1/(S1 + S2) and HC/TOC.  相似文献   
76.
Igneous rocks derived from high‐temperature, crystal‐poor magmas of intermediate potassic composition are widespread in the central Lachlan Fold Belt, and have been assigned to the Boggy Plain Supersuite. These rocks range in composition from 45 to 78% SiO2, with a marked paucity of examples in the range 65–70% SiO2, the composition dominant in most other granites of the Lachlan Fold Belt. Evidence is presented from two units of the Boggy Plain Supersuite, the Boggy Plain zoned pluton and the Nallawa complex, to demonstrate that these high‐temperature magmas solidified under a regime of convective fractionation. By this process, a magma body solidified from margin to centre as the zone of solidification moved progressively inwards. High‐temperature near‐liquidus minerals with a certain proportion of trapped interstitial differentiated melt, separated from the buoyant differentiated melt during solidification. In most cases much of this differentiated melt buoyantly rose to the top of the magma chamber to form felsic sheets that overly the solidifying main magma chamber beneath. Some of these felsic tops erupted as volcanic rocks, but they mainly form extensive high‐level intrusive bodies, the largest being the granitic part of the Yeoval complex, with an area of over 200 km2. Back‐mixing of fractionated melt into the main magma chamber progressively changed the composition of the main melt, resulting in highly zoned plutons. In the more felsic part of the Boggy Plain zoned pluton back‐mixing was dominant, if not exclusive, forming an intrusive body cryptically zoned from 63% SiO2 on the margin to 72% SiO2 in the core. It is suggested that tonalitic bodies do not generally crystallise through convective fractionation because the differentiated melt is volumetrically small and totally trapped within the interstitial space: back‐mixing is excluded and homogeneous plutons with essentially the composition of the parental melt are formed.  相似文献   
77.
Two contrasting granite types: 25 years later   总被引:16,自引:0,他引:16  
The concept of I‐ and S‐type granites was introduced in 1974 to account for the observation that, apart from the most felsic rocks, the granites in the Lachlan Fold Belt have properties that generally fall into two distinct groups. This has been interpreted to result from derivation by partial melting of two kinds of source rocks, namely sedimentary and older igneous rocks. The original publication on these two granite types is reprinted and reviewed in the light of 25 years of continuing study into these granites.  相似文献   
78.
Biotite igneous ages and well‐defined isochron ages of plutons from the composite Blue Tier Batholith and the Coles Bay area in northeastern Tasmania range from 395 to 370 Ma. The older limit of this range, for the George River granodiorite, is considerably older than any age previously recorded for NE Tasmania. The ages of the youngest plutons (Mt Paris and Anchor granites), which host cassiterite ores, record pervasive hydrothermal alteration events. The initial 87Sr/80Sr ratios of the granitoids range from 0.7061 to 0.7136 and suggest different protolith compositions, consistent with mineralogical and geochemical characteristics of each pluton. The S‐type garnetbiotite granites (Ansons Bay and Booby alia granites) have initial ratios greater than 0.7119, indicative of enriched, high Rb/Sr ratio, crustal source‐rocks of Proterozoic age (1700–800 Ma). The S‐type biotite granites (Poimena and Pearson granites) have relatively high initial 87Sr/86Sr ratios (0.7070, 0.7105) but overlap with those of the I‐type granodiorites (George River, Scamander Tier, Pyengana and Coles Bay granodiorites) which are in the range of 0.7061 to 0.7073. The initial ratios of the enriched altered plutons are poorly constrained, and on both hand‐specimen and thin‐section scales, reveal open‐system Sr isotopic patterns.

Isochron ages for the arenite‐lutite and lutite sedimentary associations of the Mathinna Beds, which are intruded by the granitoids, reflect an approach to Sr isotopic equilibrium during regional metamorphism. The metamorphic age (401 ± 7 Ma) of the early Pragian arenite‐lutite association indicates a relatively small time interval between deposition, regional metamorphism and granitoid intrusion. The isotopic age for the lutite sedimentary association (423 ± 22 Ma) is tentatively correlated with a Benambran‐age burial metamorphic event that has not previously been recorded in Tasmania.  相似文献   
79.
Advances in quality, acquisition and processing of high-resolution digital topography over the past decade have enabled geomorphologists to interpret topography in terms of tectonic processes in a quantitative and more objective way. This study defines the tectonic impact of the North Anatolian fault system (NAFS) on the evaluation and activity of the Bolu pull-apart basin using morphometric indices based on topographic maps. In this study, three different indices including valley floor width to height ratio (Vf), asymmetry factor (Af), and Stream Length Gradient Index (SL) are applied to the tectonic basin area. To detect the deviation from spatial randomness of applied indices, the weighted correlation coefficient Moran’s I is used, and results are interpreted at 99% confidence interval. According to the results, the tectonic impact of NAFS on the northern and western sides of the basin distinctly differs from one another. Clustered distribution of Vf and Af values on the southern side of the basin margin reveals that this side of the basin margin is tectonically more deformed compared with the northern side. The applied methodology reveals that the spatial analysis of the morphometric indices proved to be the effective tool in analyzing tectonic influence of the fault system on the opposite side of the basin margins.  相似文献   
80.
文章通过野外对岩脉和含矿构造特征的观察研究,得出它们之间的先后顺序为:NE向花岗斑岩脉→闪长玢岩→矿化构造,NW向岩脉最晚.早期的NE向岩脉为成矿物质提供了运移通道和最佳的容矿空间,并表现为构造矿化带常沿着岩脉产出.  相似文献   
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