苏联地形学现况及其在国民经济发展中的作用

大家知道,作为一门科学的地形学,在近四、五年来已经开辟了广泛发展的道路。 地形学自从在上世纪初从地质学中诞生出来之后,就逐渐地确定了自己的研究对象,发展了自己的研究方法。     

Deep water circulation, residence time, and chemistry in a karst complex

We investigated the hydrochemistry of a complex karst hydrosystem made of two carbonate units along a coastal lagoon. Ground water emerges on the lagoon floor from a submarine spring. In addition, thermal waters circulate through the limestone and mix with karst water near the lagoon shore. A distinction between the water from the two carbonate units is related to marine influences and human activities. In one of the massifs, the data show an incongruent dissolution of dolomite with time. In the other system, a slight contamination by saline fluids from the thermal reservoir has led to high calcium and magnesium concentrations. 36Cl, 14C, and 3H data constrain the residence time of the water, and allow for the distinguishing of four circulation types: (1) shallow surface circulation (primarily above sea level) in the karstic units with short residence times (<20 years); (2) shallow subsurface circulation (approximately 0 to -50 m) below the karstic units with residence time in the order of 50 years; (3) deep circulation at depth of 700 to 1500 m in the Jurassic limestones below thick sedimentary cover, with residence time of several thousand years for a part of the water; and (4) deep circulation at a depth of approximately 2500 m, which represents the thermal reservoir in the Jurassic units with residence time of approximately 100,000 years. An interpretative hydrogeological framework is based on the constraints of the geochemical analyses of the deep thermal system, and by water flow from the surface to the deep parts of the carbonate formations.     

膨胀性矿物引起的供水隧洞稳定性问题

为改善哥伦比亚波哥大市的供水状况，开挖了３８ｋｍ隧洞，穿过白垩系、第三系沉积岩层，隧洞投入运营４个月后，最长隧洞中喷射混凝土衬砌部分大量剥落与滑动，使水流完全中断，大多数剥落发生在以黑色页岩为主，夹间粉砂岩与灰岩的福迈克岩层中，对福迈克岩层的岩石试样作了膨胀性分析与岩石矿物分析。