Impacts of the Jessica oil spill on intertidal and shallow subtidal plants and animals

Densities of fishes, invertebrates and plants at rocky intertidal and shallow subtidal sites were censused 1-2 days prior to the Jessica oil spill and compared with information obtained for the same sites one month after the spill, both for sites impacted by oil and unaffected reference sites. While the availability of pre-spill data made this analysis one of the most powerful to date for testing impacts of oil on shoreline environments, no clear changes attributable to oiling could be identified. Discharged oil appeared to cause very little impact in the intertidal and shallow subtidal zones, with such impacts lying within the range of natural spatial and temporal variation at sites investigated. Factors considered to minimize impact in Galápagos included paucity of fully sheltered shores in spill path, moderate wave action, warm temperature, high levels of sunlight, and mixing of bunker oil with diesel.     

Effects of chitin on microbial emulsification, mineralization potential, and toxicity of bunker C fuel oil

Bunker C, one of the most frequently spilled petroleum products in the US, is difficult to remove from oiled surfaces and is relatively recalcitrant to biodegradation; therefore, emulsification and biodegradability must be optimized before bioremediation can be considered a viable treatment option. Sand from a freshly oiled beach near Dutch Harbor, Alaska, was incubated at 10 degrees C with nutrients (Bushnell-Haas (BH)) or nutrients with crab shell chitin (BH-C). BH-C amendment resulted in greater numbers of bunker C emulsifiers and greater mineralization potentials for hexadecane, phenanthrene, and fluorene than with BH only. Compared to BH alone, mineralization potentials for bunker C also were higher in BH-C, with an estimated 8% of fuel oil mineralized after 6 weeks. Microbially emulsified oil was more toxic than in uninoculated controls (p < 0.05) as measured by Microtox assays. However, toxicity was significantly lower in BH-C than BH after 4 and 6 weeks incubation (p < 0.05).     

Temporal and spatial biomonitoring of heavy metals in eastern Aegean coastal waters using Amphibalanus amphitrite

This biomonitoring study presents the spatial and temporal distributions of heavy metals in the soft tissues of a major fouling species Amphibalanus amphitrite living on hard substrate at different sites along the eastern Aegean coast. A. amphitrite has been chosen as a strong candidate for monitoring heavy metals. Sediment and seawater samples were also collected to detect their metal contents in order to gain more information on the environmental conditions and possible bioaccumulation patterns. The physico-chemical characteristics of sampling stations have been measured in order to characterize the sampling area. The order of metal concentrations in barnacles, sediment and seawater decreased in the following order Cu > Fe > Zn > Mn > Cd > Cr > Pb > Hg, Fe > Mn > Zn > Cu > Pb > Cr > Hg > Cd and Fe > Zn > Mn > Cu > Pb > Cr > Cd > Hg, respectively. These results showed that barnacles accumulate Cu in a higher degree than both sediment and seawater. Moreover, metal concentrations in barnacle have the potential for use in any future regulatory framework monitoring and eventually controlling ambient metal pollution levels.     

布什维尔德杂岩UG—2铬铁岩层中亲铜元素和铂族元素的分布

绪言 Hiemstra(1985)曾在有关UG—2层的研究中指出,铂族元素浓度的对数值随高度(从铬铁岩底部升高某一距离后的高度)直线下降。铂族元素的这一关系早已由有关元素分馏的瑞利定律所预言。然而,亲铜元素镍和铜的行为并不与此相似,尽管它们与UG—2层和梅林斯基层中的铂族元素通常有着很好的相关关系。这种区分即使存在的话大概也被随后     

1997年2月27日巴基斯坦地震（Ms=7.3）

本对１９９７年２月２７日巴基斯坦地震（Ｍｓ＝７．３）进行了分析研究,该地震发生在巴鲁奇斯坦（Ｂａｌｕｃｈｉｓｔａｎ）省的剪切带内。１９９７年２月２７日至３月２２日记录的余震分布图,提出了破裂长度及破裂取向及破裂取向的第一手资料。破裂区范围为２２ｋｍ×１１０ｋｍ,在剪切带西部呈北西走向,与区域构造趋势一致。采用Ｋｉｋｕｃｈｉ Ｋａｎａｍｏｒｉ（１９９１）公式计算震源机制解,表明西北－南东向冲断层为     

Estimating ground water recharge from topography, hydrogeology, and land cover

Proper management of ground water resources requires knowledge of the rates and spatial distribution of recharge to aquifers. This information is needed at scales ranging from that of individual communities to regional. This paper presents a methodology to calculate recharge from readily available ground surface information without long-term monitoring. The method is viewed as providing a reasonable, but conservative, first approximation of recharge, which can then be fine-tuned with other methods as time permits. Stream baseflow was measured as a surrogate for recharge in small watersheds in southeastern Wisconsin. It is equated to recharge (R) and then normalized to observed annual precipitation (P). Regression analysis was constrained by requiring that the independent and dependent variables be dimensionally consistent. It shows that R/P is controlled by three dimensionless ratios: (1) infiltrating to overland water flux, (2) vertical to lateral distance water must travel, and (3) percentage of land cover in the natural state. The individual watershed properties that comprise these ratios are now commonly available in GIS data bases. The empirical relationship for predicting R/P developed for the study watersheds is shown to be statistically viable and is then tested outside the study area and against other methods of calculating recharge. The method produces values that agree with baseflow separation from streamflow hydrographs (to within 15% to 20%), ground water budget analysis (4%), well hydrograph analysis (12%), and a distributed-parameter watershed model calibrated to total streamflow (18%). It has also reproduced the temporal variation over 5 yr observed at a well site with an average error < 12%.     

根据诱发微震确定岩石的大尺度原地渗透张量

利用钻孔的水力学测试或随机的注水试验诱发的地震发射信号,我们了一种确定渗透率张量的方法,对于完全非质岩体,当记录到地震发射信号时,该方法给出了确定其渗透张量的唯一解,该方法是对Ｓｈａｐｉｒｏ等人（１９９７）针对各向同性情况提出的方法的扩展和延伸,它要求假设：水力诱发的微震触发前缘的扩展如同第二类压缩性比奥特波（对应于孔隙压力松弛过程）在等效的均质、各向同性饱和态的也隙障性介质中传播和扩展,该等效介质中的渗透率张量即是该各向异性岩石体积放大至地震活动区域铁尺寸时的渗透率张量,利用Ｈｏｔ Ｄｒｙ Ｒｏｃｋ Ｓｏｕｓ－Ｆｏｒｅｔｓ试验过程中采集到的微震数据（Ｙｙｅｒ ｅｔ ａｌ．１９９４）我们证实了该方法,这些数据表明,相对应的岩石体积以定向裂隙系统导致的明显的渗透率各向异性为特征,渗透率张量的最大主分量近于垂向,它     

Assessment of the historical trace metal contamination of sediments in the Elizabeth River, Virginia

Two sediment cores (Southern Branch, PC-1, and Western Branch, WB-2) were taken from the highly industrialized Elizabeth River, Virginia. The concentrations of trace metals cadmium, cobalt, chromium, copper, nickel, lead and zinc, major elements iron, manganese and aluminum, organic carbon content and the specific surface area of the sediments were determined in each of the cores. Down-core variations in metals varied significantly in each core with maximum contamination events occurring at different times in different portions of the river. In PC-1, maximum metal concentrations were seen after the appearance of (137)Cs. In contrast, the highest levels in WB-2 occurred well before the appearance of (137)Cs. Although stricter environmental regulations have caused a decrease in metal concentrations since the 1980s, the concentrations in the surface sediments of many trace metals were elevated to levels 2-5 times higher than the levels at the bottom of the cores in both the Southern and Western Branches of the river.     

中国最老岩石和锆石

在中国大陆的许多地区都已发现大于3.4Ga的锆石和岩石.鞍山是全球仅有几个存在≥3.8Ga岩石的地区之一.它们以不大的规模存在于白家坟、东山、深沟寺杂岩中,由糜棱岩化奥长花岗岩、条带状奥长花岗岩和变质石英闪长岩组成.近年来,在鞍山地区还发现了许多3.7～3.6Ga岩石和锆石.锆石Hf同位素组成表明鞍山地区在3.8～3.6Ga期间存在周期性的地幔添加和陆壳形成.除鞍山外,在中国许多地区的不同类型岩石中也获得了≥3.4Ga锆石,虽然它们大多数都是碎屑和残余成因.(1)华北克拉通冀东铬云母石英岩中3.85～3.55Ga碎屑锆石:(2)华北克拉通信阳中生代火山岩长英质麻粒岩中3.66Ga岩浆锆石;(3)华南克拉通宜昌地区杨子地块新元古代砂岩中3.80Ga碎屑锆石(一颗);(4)华南克拉通华夏地块新元古代一古生代变质沉积岩中3.76～3.6Ga碎屑锆石;(5)西北地区塔里木地块阿克塔什塔格地区古元古代片麻状花岗岩中3.6Ga残余锆石;(6)西秦岭奥陶纪变质火山岩中4.08Ga捕掳锆石(一颗);(7)西藏普兰地区奥陶纪石英岩中4.1Ga碎屑锆石(一颗,有3.61Ga增生边).一些古老锆石有高达4.1～4.0Ga的Hf同位素模式年龄.在中国,>3.4Ga地壳物质的比例以往被低估了,发现冥古宙和始太古代物质的可能性仍然存在,它们将对中国早期陆壳演化提供新的制约.