Partition,secession and peace in our time

This paper deals with the comparative issues of partition and secession, both as territorial issues and as problems of sovereignty, focussing on the state system. The democratic principle of national self-determination is recognised by the international community but is unequally and cynically applied, designed to protect the existing system of states. Partition, division, and secession, may heighten tensions between the parties and greatly magnify the extent of any future conflict, by creating new sovereign states. The weakening of the nation-state within its own borders by forces of globalization unleashes intensely nationalist sentiments, increasing instability within the state, and to partition or secession which, in turn, further destabilize the interstate system. This paper was written while an Academic Visitor in the Department of Geography, Queen Mary and Westfield College, University of London.     

Accretion disk boundary layers: Their structure and stability

The importance of the boundary layer has been known for some time, (see Lynden-Bell and Pringle, 1974). Yet this region of the disc has never been studied in great depth. We present here some calculations which are undertaken in order to explore some of the complex processes which can go on in this region. It is shown how the structure of the boundary layer is affected by viscosity, how oscillations can occur in the outer disk and boundary layer regions. We also show how they disperse and dissipate.Paper presented at the IAU Colloquium No. 93 on Cataclysmic Variables. Recent Multi-Frequency Observations and Theoretical Developments, held at Dr. Remeis-Sternwarte Bamberg, F.R.G., 16–19 June, 1986.     

Multi-level Effects of Severe Storms on an Offshore Temperate Reef System: Benthic Sediments, Macroalgae, and Implications for Fisheries

Abstract. Episodic events have been shown to strongly affect structure and function of marine benthic ecosystems. Severe storms can have profound effects on the distribution of marine sediments which could, in turn, influence the development of benthic communities. The rich and diverse epibenthic communities on the United States mid-Atlantic continental shelf owe their existence to the presence of a complex sequence of rocky outcrops. An unusually strong storm struck this shelf system in March 1993. Two of these carbonate platforms had been characterized by moderate sediment cover for at least the previous two years, but bottom water velocities generated by this storm removed considerable amounts of sediment from these upper flat hardbottom habitats. Macroalgal cover on these platforms dramatically increased between 1992 and 1993 with the increased exposure of hard substrate for attachment. The edges of the outcrops (scarps and rubble ramps), which are usually free of sediment, maintained their dense algal cover. Settlement blocks placed in various sub-habitats showed little variation in algal cover among flat hardbottom and scarp areas during both years, indicating that available hard substrate habitat may be the primary limiting factor for algal growth on the North Carolina continental shelf. Since macroalgal meadows provide food and shelter for juvenile fish, the increase in critical habitat following these storms may have implications for recruitment of economically important fish species. Thus, indirect effects of episodic storms, i.e ., redistribution of sand bodies leading to algal meadow development over large spatial scales, may have important consequences for benthic community development and persistence in temperate reef systems.     

Welded slump-graded sand couplets: evidence for slide generated turbidity currents

Some massive channelized strata preserved in the rock record are characterized by a lower slump member which evolves upward to a turbidite. This merging is indicative of probable generation of sediment gravity flows from submarine sliding. Conditions essential for deposition of such sequences are short transport distance between point of failure and depositional site, and an environment likely to retain both facies. Fan valleys are a likely setting for welded couplets: flowing sand, initiated by the sliding event, comes to rest at nearly the same time and position as the slump mass deposited near the base of the valley wall and in the axis proper.     

Variable deposition rates on the slope and rise off the Mid-Atlantic States

Pronounced variations in slope topography and offshelf spillover have produced a three-fold difference (9 to 25 cm/1,000 yr) in Late Quaternary deposition rates among slope cores southeast of the Mid-Atlantic States. Upper rise cores revealed a high rate but lower core-to-core variability (20 to 44 cm/1,000 yr), largely the result of slope bypassing, i.e., effects of gravity-controlled downslope transport. A transport model suggests temporary slope sediment storage and higher accumulation of mud in more distal rise regions. Eustatic change accounts for the four-fold decrease in slope deposition rate between the Late Pleistocene and Holocene.     

Trans-South Atlantic air link in World War II

German-Italian military successes and the fame of General Rommel's Afrika Korps in 1941 spelled disaster for the British war effort in Libya-Egypt. American military assistance was requested and freely given; this was several months before the United States entered the war! Pan American World Airways was the chosen instrument for building a series of airfields in Africa capable of receiving the planes ferried across the ocean from Recife, Brazil.Besides its reputation as the world's leading airline, Pan Am already had a major aircraft servicing facility at Recife. Liberia, because of its proximity to South America, became the first major West African bridgehead for this South Atlantic ferry route. A few existing and numerous newly constructed airfields between Liberia and Khartoum served as the emergency landing, refueling, maintenance and housing sites. The Nile was followed downstream from Khartoum; American-supplied warplanes played an important role in the pivotal Egyptian battle of El-Alemain in October, 1942. Once the threat to Egypt had subsided, the Brazil — West Africa air link was expanded to include a route through Central Africa, primarily to tap a supply of uranium from what was then the Belgian Congo (now Zaire). Khartoum served a new air ferry route to British India via Aden and Karachi. Transport aircraft used in the China-Burma-India theatre of operations were supplied over this ever-expanding air link. A spur to Basra (Iraq) and Tehran provided a secret diplomatic connection to the Soviet Union before the epic struggle at Stalingrad began in earnest. General Doolittle's surviving Tokyo raiders returned to the United States over segments of this long air route. Most of the airfields lost their locational significance after the war. A few, however, were to become their countries' international airports.More correctly, the Trans-South Atlantic Transport and Ferry Service. The author appreciates the fact that except for a secondary route through Central Africa, this wartime air connection was to the North of the Equator and technically, in the North Atlantic. Use of terminology then as now is to differentiate this particular route from the important Newfoundland to Prestwick (Scotland) air bridge.     

Osmium isotope ratios of PGM grains associated with the Freetown Layered Complex,Sierra Leone,and their origin

Osmium isotope ratios for two types of platinum group mineral (PGM) nuggets of eluvial (residual) origin, associated with the Freetown Layered Gabbro Complex, were determined in-situ using an ion microprobe. The values for erlichmanite nuggets are 1.08. Those for PGM inclusions in Pt–Fe alloy nuggets are higher, ranging from 1.2 to 2.1. Ratios of¹⁸⁷Os/¹⁸⁶Os vary between the nuggets, but they are consistent within individual nuggest. The data suggest early formation of the erlichmanite nuggets, prior to a postulated substantial contribution of crustal Os. The Pt–Fe alloy nuggets, on the other hand, were formed later in a residual melt which was contaminated by crustal Os due to the assimilation (<10%) or the gaseous/fluid transport of Os from Archaean host rocks into the magma. The lack of systematic mineralogical and chemical changes of the Complex and extensive granulitization in the adjacent host rocks and xenoliths may favor the latter process.The lack of high¹⁸⁷Os/¹⁸⁶Os ratios, consistent¹⁸⁷Os/¹⁸⁶Os values within individual nuggets and their textures and mineralogy suggest that the studied PGM nuggets were not formed during lateritization or in low-temperature depositional environments.     

A third port for Southwest Africa/Namibia?1)

The end of South African control over its former Southwest Africa Mandate and the imminent emergence of an independent Namibia provide opportunity for reorientation of South-Central Africa's export metal trade. How rapid this may occur will depend in some measure upon the political and commercial environment still to evolve in the Walvis Bay exclave. This, in turn, may be related to the future treatment of Namibia's critically placed white minority and to the political rhetoric of a SWAPO government. Any reorientation of the region's export trade will place the strategic CapriviStrip in a new geopolitical perspective, one better resembling that which Imperial Germany had in mind for this sliver of land than had evolved during 75 years of South African rule. Expansion of trade through the Caprivi Corridor should stimulate transportation development in NE Namibia. Were the Walvis Bay situation not to be resolved in a manner conducive to its future use by an independent Namibia or by neighboring states, then pressure to build a new deep water port will accelerate. The strategically placed fishing industry and the use of these waters by large foreign trawler fleets might be the stimuli for the initial financing of the construction of any new port. Luederitz, the country's true port, is inadequate to the task of modern commerce and is located too far from the economic and population core of the country.     

Carbon and hydrogen isotope fractionation associated with the aerobic microbial oxidation of methane, ethane, propane and butane

Carbon isotope fractionation factors associated with the aerobic consumption of methane (C1), ethane (C2), propane (C3), and n-butane (C4) were determined from incubations of marine sediment collected from the Coal Oil Point hydrocarbon seep field, located offshore Santa Barbara, CA. Hydrogen isotope fractionation factors for C1, C2 and C3 were determined concurrently. Fresh sediment samples from two seep areas were each slurried with sea water and treated with C1, C2, C3 or C4, or with mixtures of all four gases. Triplicate samples were incubated aerobically at 15 °C, and the stable isotope composition and headspace levels of C1-C4 were monitored over the course of the experiment. Oxidation was observed for all C1-C4 gases, with an apparent preference for C3 and C4 over C1 and C2 in the mixed-gas treatments. Fractionation factors were calculated using a Rayleigh model by comparing the δ¹³C and δD of the residual C1-C4 gases to their headspace levels. Carbon isotope fractionation factors (reported in ε or (α-1) × 1000 notation) were consistent between seep areas and were −26.5‰ ± 3.9 for C1, −8.0‰ ± 1.7 for C2, −4.8‰ ± 0.9 for C3 and −2.9‰ ± 0.9 for C4. Fractionation factors determined from mixed gas incubations were similar to those determined from individual gas incubations, though greater variability was observed during C1 consumption. In the case of C1 and C3 consumption, carbon isotope fractionation appears to decrease as substrate becomes limiting. Hydrogen isotope fractionation factors determined from the two seep areas differed for C1 oxidation but were similar for C2 and C3. Hydrogen isotope fractionation factors ranged from −319.9‰ to −156.4‰ for C1 incubations, and averaged −61.9‰ ± 8.3 for C2 incubations and −15.1‰ ± 1.9 for C3 incubations. The fractionation factors presented here may be applied to estimate the extent of C1-C4 oxidation in natural gas samples, and should prove useful in further studying the microbial oxidation of these compounds in the natural environment.     

贾湖遗址人骨的稳定同位素分析

古代人类食谱研究是生物考古的重要组成部分, 也是当前国际科技考古领域的研究前沿. 利用稳定同位素分析方法, 尝试揭示贾湖遗址先民的食物结构以及生活方式的变化. 人骨的骨胶原含量、C含量以及N含量, 尤其是骨胶原C/N摩尔比的分析表明, 28个样品中13个已经受到埋藏环境的污染, 不能用作食谱分析. 其余样品骨胶原的δ ¹³C((-20.37±0.53)‰), 表明先民主要以C₃类作为食物来源. 根据骨胶原中δ¹³C和δ ¹⁵N的不同，先民的食谱可划分为4类. 两者相关性的缺乏, 当与该遗址以农耕经济为主有关. 骨胶原δ¹⁵N和羟磷灰石δ¹³C纵贯整个文化段的变化, 反映了先民从狩猎转向采集、捕捞直至发展稻作农业和家畜饲养的改变. 而羟磷灰石中δ ¹⁸O则无明显变化, 揭示了该遗址气候较为稳定.