浅层土（溶）洞的地震探测问题探讨

对埋深≤30m的土(溶)洞做了理论模型,并对其进行研究(高斯射线束法),再依据三维地震勘探方法,根据我院在工作中的实测成果,指出了土(溶)洞异常的解释理论要点和解释依据,说明了土(溶)洞在实际工作中的复杂多变性。     

Characterisation of Heterotrophic Microorganisms Isolated form the "Grotta Azzura" of Cape Palinuro (Salerno, Italy)

Abstract. Hydrothermal vent ecosystems have been extensively investigated during the last 20 years; shallow water hot springs (typically found below 50 m depth) have also been studied, and from these ecosystems many thermophilic and hyperthermophilic organisms were isolated and described.
The submarine caves of Cape Palinuro were discovered long ago, but only during the last decades were geological and biological investigations carried out, yielding a large number of reports on this fascinating environment. During the last two years, several samples of water, mud, and/or bacterial mat were collected within the "Grotta Azzurra", and enrichment experiments were performed using peptone, starch, glucose or pullulan as main organic nutrients. Many heterotrophic strains were isolated and most of them grew optimally between 37 and 43 ° C with the addition of 0-2 % NaCl. Growth was usually observed between 10 and 50 ° C the range of growth pH was 4 to 9, and NaCl concentrations up to 10–12 % were tolerated in most cases.
The analysis of 16S rDNA performed with the most representative isolates showed a close phylogenetic relationship with the genera Bacillus, Vibrio, Citrobacter and Escherichia. Moreover, an isolate showing morphological and physiological similarities with the genus Enterococcus was characterised and taxonomically described based on the 16S rDNA sequence.     

From subsurface to surface: a multidisciplinary approach to decoding uplift histories in tectonically-active karst landscapes

We present an integrated study of subsurface and surficial karst landforms to unravel the uplift history of karst landscape in a tectonically-active area. To this end, we apply a multidisciplinary approach by combining cave geomorphology and Th/U dating of speleothems with remote sensing plus geophysical imaging of surface landforms. We use as an example Mt. Menikio in northern Greece where four caves share well-defined epiphreatic/shallow phreatic characteristics that are related to the distribution of surface and buried doline fields and provide evidence for three distinct water table stillstands (e.g. expressed as cave levels) now lying at ~130 m, ~800 m and ~1600 m a.m.s.l. Our dating constraints delimit the age of the lower water table stillstand prior to 77 ka ago and imply a maximum rate of relative base level drop of 0.45 mma^-1, which is consistent with relative tectonic uplift rate estimates along currently active normal faults. We interpret the elevation of the higher water table stillstands to reflect earlier phases of uplift related to the regional tectonic events associated with the development of the North Anatolian Fault and the Northern Aegean area. Our analysis shows that the combined study of epiphreatic/shallow phreatic caves and surficial karst landforms together, is a robust way to investigate the uplift history of a karst landscape in a tectonically-active setting. © 2019 John Wiley & Sons, Ltd.     

Distribution of trace metals in anchialine caves of Adriatic Sea,Croatia

This study presents results of the first comprehensive research on ecotoxic trace metals (Cd, Pb, Cu and Zn) in aquatic anchialine ecosystems. Data show the influence of hydrological and geological characteristics on trace metals in highly stratified anchialine water columns.     

陆地声纳法在探测岩溶区高铁隧道基底隐患中的应用

沪昆高铁的麻拉寨隧道和贵广高铁的高天隧道在联调联试阶段均发生不均匀沉降和底鼓现象,为了摸清隧道基底致灾原因并对注浆质量进行检测研究,采用陆地声纳法在隧道岩溶段进行了检测,在基底下方探测出较多中、小溶洞,多组中、小断层延伸到基底下方使溶洞之间互相连通,由于雨季隧道周边水压力强烈的变化,造成了隧道不均匀沉降与底鼓,根据数据图像的特殊反应确定了破碎区域和浆注入区,依据探测结果确定治理方案并在治理施工中得到验证。      

Carbon dioxide concentration in temperate climate caves and parent soils over an altitudinal gradient and its influence on speleothem growth and fabrics

Carbon dioxide (CO₂) concentrations in caves and parent soils in the Italian Alps have been studied along a 2100 m altitudinal range – corresponding to a mean annual temperature (MAT) range of 12°C – in order to investigate the relationship between MAT, soil pCO₂ and cave air pCO₂, and to test the influence of soil pCO₂ on speleothem growth and fabric to ultimately gain insight into their palaeoclimatic significance in temperate climate settings. Our findings indicate that soil CO₂ is linearly correlated to MAT and its mean annual concentration is described by the equation: soil CO₂ (ppmv) = 1112 + 460 MAT. Soil pCO₂ can also be exponentially correlated to actual evapotranspiration. The pCO₂ in the aquifer is linearly correlated to MAT at the infiltration site and is more influenced by summer soil pCO₂. Cave air CO₂ in the innermost part of the caves exhibits a similar seasonal pattern, and commonly reaches concentrations of about 15% to 35%, with respect to the corresponding soil values, and is exponentially correlated to the MAT at the infiltration site. The combination of these parameters (soil pCO₂, dripwater pCO₂ and cave air pCO₂) results in speleothem growth and controls their fabrics which are typical of four MAT/elevation belts broadly corresponding to the present‐day vegetation zones. In the lower montane zone [100–800 m above sea level (a.s.l.)] speleothems mostly consist of columnar fabric, in the upper montane zone (800–1600 m a.s.l.) both columnar and dendritic fabrics are common, the Subalpine zone (1600–2200 m a.s.l.) is characterized mostly by moonmilk deposits, whereas in the Alpine zone (above 2200 m a.s.l.) no speleothems are forming today. Therefore, fabric changes in fossil speleothem can potentially be used to reconstruct MAT changes in temperate climate karst areas. Copyright © 2015 John Wiley & Sons, Ltd.     

Speleogenesis of an exhumed hydrothermal sulphuric acid karst in Cambrian carbonates (Mount San Giovanni,Sardinia)

In the past few years the systematic study of caves intercepted by mine workings in southwest Sardinia has permitted us to observe morphologies due to rare speleogenetic and minerogenetic processes related to ancient hydrothermal activity. These relic morphologies are slowly being overprinted by recent speleogenetic processes that tend to obscure the hypogene origin of these caves. A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves. Cave formation had already started in Cambrian times, but culminated in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary a variety of minerals formed inside the caves: calcite and aragonite, that yielded sequences of palaeo‐environmental interest, and also barite, phosgenite, hydrozincite, hemimorphite and many others. These minerals are in part due to a phreatic thermal hypogenic cave forming phase, and in part to later epigene overprinting in an oxidizing environment rich in polymetallic ores. Massive gypsum deposits, elsewhere typical of this kind of caves, are entirely absent due to dissolution during both the phreatic cave formation and the later epigenic stage. Copyright © 2013 John Wiley & Sons, Ltd.     

Fractal dimensions and geometries of caves

Lengths of all caves in a region have been observed previously to be distributed hyperbolically, like self-similar geomorphic phenomena identified by Mandelbrot as exhibiting fractal geometry. Proper cave lengths exhibit a fractal dimension of about 1.4. These concepts are extended to other self-similar geometric properties of caves with the following consequences.Lengths of a cave is defined as the sum of sizes of passage-filling, linked modular elements larger than the cave-defining modulus. If total length of all caves in a region is a self-similar fractal, it has a fractal dimension between 2 and 3; and the total number of linked modular elements in a region is a self-similar fractal of the same dimension. Cave volume in any modular element size range may be calculated from the distribution.The expected conditional distribution of modular element sizes in a cave, given length and modulus, also is distributed hyperbolically. Data from Little Brush Creek Cave (Utah) agree and yield a fractal dimension of about 2.8 (like the Menger Sponge). The expected number of modular elements in a cave equals approximately the 0.9 power of length of the cave divided by modulus. This result yields an intriguing parlor trick. An algorithm for estimating modular element sizes from survey data provides a means for further analysis of cave surveys.     

新型膨大管柱堵漏工具的研究与试制

为了提高钻遇断层、大裂缝、溶洞及流水溶洞情况发生的失返性漏失堵漏的成功率,研制了一种新型膨大管柱堵漏工具。该工具直接送达漏层,使堵漏材料在受限空间内凝固,并在井眼轨迹穿过的通道上建立所需体积和强度的堵塞,从而解决失返性漏失问题。介绍了该堵漏工具的结构组成、选材、制造工艺和使用方法。     

塔里木盆地塔河油田TH12402井区中下奥陶统古岩溶洞穴发育模式*

塔里木盆地塔河油田TH12402井区位于志留系覆盖区,发育典型的古岩溶缝洞型储集层,是塔河油田西北部奥陶系主要的产建阵地之一。基于三维地震数据、测井和钻井资料,并结合地震属性提取技术,对该区下奥陶统岩溶发育条件和储集层发育特征进行了研究,探讨了岩溶洞穴的控制因素和发育模式。结果表明: TH12402井区处于北西向次级鼻状构造的南翼,该区发育加里东中期Ⅲ幕古岩溶作用,岩溶地形以低幅度的溶丘和洼地为主,地表水系呈南北向汇流且分支水系相对欠发育;岩溶储集空间以大型迷宫状岩溶管道和分散的孤立状洞穴为主,主要分布在不整合面以下40~100m,且以未充填为主;近东西向的走向断层、次级鼻状构造以及上奥陶统地层尖灭线联合控制了古岩溶洞穴的发育,形成了平缓岩溶地貌区走向断裂汇流型岩溶洞穴模式。上述成果为相似井区的古岩溶储集层预测和井位部署提供了理论依据。