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通过对芬兰湾第四纪沉积断面声学探测和地质钻探结果发现与波罗的海盆地各发育阶段相适应的4种结构杂岩体。结构杂岩体的形成受结构和冰川动力作用控制,还受海底地形制约。水动力作用对与海相有关的新杂岩体的形成起着决定性作用,因为这些作用增强了海底侵蚀作用,并形成了复杂的堆积一侵蚀组合形态,即现时所称的海底流地质痕迹。本文以科学考察船“瓦维洛夫院士·谢尔盖”号第9航次于芬兰湾东部进行声学探测和地质钻探获得资料为基础(1991年,见图1),声学探测使用的是多道回声探测仪,波段为2.5~5.okHZ。在软底质,探测深度达几… 相似文献
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从矿物学探讨庙岛列岛黄土成因 总被引:1,自引:1,他引:1
1975年3—7月,作者对庙岛列岛17个岛屿及蓬莱县沿岸分布普遍的第四纪堆积物——黄土进行了观测。现将野外观察和室内矿物分析结果叙述如下。 相似文献
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1 我国海岛水资源状况 1.1 海岛赋水条件和水质状况海岛赋水条件是由海岛所处地理位置、地貌、水文地质条件等决定。面积较小的岛屿,一般水文地质条件不佳,因基岩裸露、地形陡峭,比降大、降水直接排泄。因无松散堆积物盖层,缺少第四系含水层,往往无汇水洼地,虽有大气降水,但也不能储存。加上岩石致密,渗透性差,无良好的地下水补给集水区。所以,这些小 相似文献
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Panno SV Hackley KC Hwang HH Greenberg SE Krapac IG Landsberger S O'Kelly DJ 《Ground water》2006,44(2):176-187
Elevated concentrations of sodium (Na+) and chloride (Cl-) in surface and ground water are common in the United States and other countries, and can serve as indicators of, or may constitute, a water quality problem. We have characterized the most prevalent natural and anthropogenic sources of Na+ and Cl- in ground water, primarily in Illinois, and explored techniques that could be used to identify their source. We considered seven potential sources that included agricultural chemicals, septic effluent, animal waste, municipal landfill leachate, sea water, basin brines, and road deicers. The halides Cl-, bromide (Br), and iodide (I) were useful indicators of the sources of Na+-Cl- contamination. Iodide enrichment (relative to Cl-) was greatest in precipitation, followed by uncontaminated soil water and ground water, and landfill leachate. The mass ratios of the halides among themselves, with total nitrogen (N), and with Na+ provided diagnostic methods for graphically distinguishing among sources of Na+ and Cl- in contaminated water. Cl/Br ratios relative to Cl- revealed a clear, although overlapping, separation of sample groups. Samples of landfill leachate and ground water known to be contaminated by leachate were enriched in I and Br; this provided an excellent fingerprint for identifying leachate contamination. In addition, total N, when plotted against Cl/Br ratios, successfully separated water contaminated by road salt from water contaminated by other sources. 相似文献