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锯缘青蟹秋苗土池越冬的试验研究 总被引：4，自引：0，他引：4
本文报道１９９３和１９９４年秋季作者培育的部分锯缘青蟹仔蟹苗土池越冬试验。结果表明人工培育的青蟹苗在闽南地区的自然条件下,可以在室外土池完全越科,成活率可达６０－８０％,水温是影响青蟹生命活动的主要因素;由于越冬期间青蟹营养积累不足,导致难以顺利地完成越冬后的第一次生长蜕壳,造成大量死亡,这是影响青蟹越冬存活率的主要因素之一;越科后期病死青蟹肝胰组织进行涂片处理,发现６只受检蟹中２只肝胰组织中有日 相似文献
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Earthquake triggering of mud volcanoes 总被引：1，自引：0，他引：1
Mud volcanoes sometimes erupt within days after nearby earthquakes. The number of such nearly coincident events is larger than would be expected by chance and the eruptions are thus assumed to be triggered by earthquakes. Here we compile observations of the response of mud volcanoes and other geologic systems (earthquakes, volcanoes, liquefaction, ground water, and geysers) to earthquakes. The compilation shows a clear magnitude–distance threshold for triggering, suggesting that these seemingly disparate phenomena may share similar underlying triggering mechanisms. The compilation also shows that pre-existing geysers and already-erupting volcanoes and mud volcanoes are much more sensitive to earthquakes than quiescent systems. 相似文献
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Quality control in mud coring 总被引：1，自引：0，他引：1
W. R. Parker 《Geo-Marine Letters》1991,11(3-4):132-137
Consideration of factors influencing the interaction between a corer and sediment suggest the likelihood of significant and
anisotropic straining of the particle framework during coring. Direct observations allow the coring process to be discretised,
the relative motion of corer, core and sediment to be visualized and confirm that the development of differences between corer
penetration and core length is not a continuous process. Records suggest the possibility of dislocation of the relative positions
of porewater and particle framework, which may lead to the disequilibration of sorbed species. 相似文献
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The series connection of multistage pumping module is the common concept of deepwater riserless mud recovery drilling system. In this system, the influence of the mass of pumping module on the vibration of mud recovery line cannot be ignored, and the lumped mass method has been utilized to discretize the mud recovery line. Based on the analysis of different boundary conditions, the paper establishes the axial forced vibration model of the mud recovery line considering the seawater damping, and the vibration model analysis provides the universal solution to the vibration model. An example of the two-stage pumping system has been used to analyze the dynamic response of mud recovery line under different excited frequencies. This paper has the important directive significance for the application of riserless mud recovery drilling technology in deepwater surface drilling. 相似文献
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A. Mazzini H. Svensen S. Planke I. Guliyev G.G. Akhmanov T. Fallik D. Banks 《Marine and Petroleum Geology》2009
The worlds >1500 mud volcanoes are normally in a dormant stage due to the short duration of eruptions. Their dormant stage activity is often characterized by vigorous seepage of water, gas, and petroleum. However, the source of the fluids and the fluid–rock interactions within the mud volcano conduit remain poorly understood. In order to investigate this type of activity, we have combined satellite images with fieldwork and extensive sampling of water and gas at seeping gryphons, pools and salsa lakes at the Dashgil mud volcano in Azerbaijan. We find that caldera collapse faults and E–W oriented faults determine the location of the seeps. The seeping gas is dominated by methane (94.9–99.6%), with a δ13C (‰ V-PDB) in the −43.9 to −40.4‰ range, consistent throughout the 12 analysed seeps. Ethane and carbon dioxide occur in minor amounts. Seventeen samples of seeping water show a wide range in solute content and isotopic composition. Pools and salsa lakes have the highest salinities (up to 101,043 ppm Cl) and the lowest δ18O (‰ V-SMOW) values (1–4‰). The mud-rich gryphons have low salinities (<18,000 ppm Cl) and are enriched in 18O (δ18O = 4–6‰). 相似文献
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Reuse of dredged marine sediments for land reclamation is a sustainable method for disposing the large quantities of dredged spoil, accumulating every year worldwide. However, due to their high water content and low permeability, dewatering and self-sedimentation of the material takes a long time to be completed. Therefore, different methods, such as prefabricated vertical drains and vacuum preloading, are used to improve the consolidation properties of the dredged mud at the port of Brisbane. Among these stabilization methods, vacuum preloading is determined as the most effective method to increase the consolidation of the dredged mud. However, clogging during vacuum consolidation is undesirable. Therefore, electrokinetic stabilization draws attention since it is an environmentally friendly and time efficient method to dewater and consolidate dredged mud significantly. The effectiveness of the electrokinetic stabilization depends on the properties of the soil and the electrode configurations. One-dimensional and two-dimensional electrode configurations are the most popular configurations. In this study, the effect of one-dimensional electrode configuration, which is installation of electrodes in arrays of anodes and cathodes on consolidation parameters of dredged mud, is investigated. Based on this study, the dredged mud sediments can be stabilized using one-dimensional electrokinetic stabilization which resulted in improving compression index and coefficient of volume compressibility and reduction of soil plasticity index. 相似文献
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Pumping rate of a mud shrimp,Callianassa japonica, in its burrow was measured by continuous monitoring of dye concentration in the burrow water. Measurement of dilution in
two directions from stained overlying seawater to normal burrow water andvice versa, gave no significant difference in results. The rate of exchange (v) of burrow water was estimated from,v=(u
t−u
0)V/(m−u
t−1)t, whereV is volume of burrow water,u
0,u
t−1 andu
tis dye concentration of burrow water at time 0,t−1 andt, respectively, andm is dye concentration of overlying water. The pumping rate ranged from 0.63 to 5.46 ml min−1, which corresponded to a turnover time for the burrow water of 7–51 min. Short term changes in the pumping rate were correlated
to intermittent behaviour of the shrimp in the burrow. 相似文献
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C. Ranz-Guerra 《Geo-Marine Letters》1991,11(3-4):172-173
Mud is a complex mixture of water and solid particles and acoustics can help on its control. The mud layer, as an acoustic
channel, is characterized by its propagation constant relating the wave frequency, the sound velocity, and the energy absorption.
If the input acoustic pulse is known, it is feasible to easily characterize the mud layer as a low pass filter (absorption);
if it is also possible to insonify the mud with sound of both low and high frequencies, the sound speed of the mud mixture
can be evaluated, and the propagation constant is then known. 相似文献
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Understanding fluid mud in a dynamic environment 总被引：1，自引：0，他引：1
Ashish J. Mehta 《Geo-Marine Letters》1991,11(3-4):113-118
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Fluid mud accumulation processes in an estuary 总被引：4，自引：0，他引：4
Maynard M. Nichols 《Geo-Marine Letters》1984,4(3-4):171-176
Fluid mud accumulates as pools and blanket deposits greater than 20 cm thick in channels of the James Estuary. It forms mainly in the turbidity maximum zone, a site of high near-bed concentrations (0.5 to 2 g/liter), intensive resuspension, and fast sedimentation (1 to 8 g/cm2/yr). Accumulation is promoted by stratification of interfacial fluid and pore water, by the pseudoplastic behavior of the mud with relatively high viscosity at low shear rates, by the high suspended sediment concentrations, and by resultant rapid-settling flux relative to the consolidation rate in the hindered state.This is Contribution 1211 from the Virginia Institute of Marine Science, Gloucester Point, VA 23062. 相似文献
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深水蕴藏着丰富的油气资源,国内的油气勘探开发重点正在向海上转移。国外有相对成熟的深水钻井工艺,国内的深水钻井工艺研究刚刚起步,与之相配套的深水录井工艺在国内几乎还是空白。从HSE保障、油气显示发现及解释评价、优化钻井、钻井信息化建设等方面分析了国内深水钻井对录井的需求;从保障钻井安全、工程参数获取、岩屑采集、钻井液气体分析、资料的综合解释等方面阐述了深水钻井给录井带来的影响,并提出了对策,对深水录井的发展提出建议。 相似文献
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F. Montserrat W. Suykerbuyk R. Al-Busaidi T.J. Bouma D. van der Wal P.M.J. Herman 《Journal of Sea Research》2011,65(1):170-181
Benthic ecosystem engineering organisms attenuate hydrodynamic or biogeochemical stress to ameliorate living conditions. Bioturbating infauna, like the lugworm Arenicola marina, determine intertidal process dynamics by maintaining the sediment oxygenated and sandy. Maintaining the permeability of the surrounding sediment enables them to pump water through the interstitial spaces, greatly increasing the oxygen availability. In a field experiment, both lugworm presence and siltation regime were manipulated to investigate to what extent lugworms are able to cope with sedimentation of increasing mud percentage and how this would affect its ecosystem engineering. Fluorescent tracers were added to experimentally deposited mud to visualise bioturbation effects on fine sediment fractions. Lugworm densities were not affected by an increasing mud percentage in experimentally deposited sediment. Negative effects are expected to occur under deposition with significantly higher mud percentages. Surface chlorophyll a content was a function of experimental mud percentage, with no effect of lugworm bioturbation. Surface roughness and sediment permeability clearly increased by lugworm presence, whereas sediment erosion threshold was not significantly affected by lugworms. The general idea that A. marina removes fine sediment fractions from the bed could not be confirmed. Rather, the main ecosystem engineering effect of A. marina is hydraulic destabilisation of the sediment matrix. 相似文献
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《Coastal Engineering》2006,53(9):793-797
A systematic approach for predicting the mean erosion and mean deposition rates of mud beneath random waves is derived. This has been accomplished by applying formulas valid for regular waves and by describing the waves as a stationary Gaussian narrow-band random process. The present approach covers flow in the laminar, smooth turbulent and rough turbulent flow regimes. Examples are given, using data typical for field conditions representing laminar and smooth turbulent flow conditions, which are the most common flow regimes over mud beds. 相似文献
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The Guyana coastal system is characterized by very thick deposits of Amazon mud and high mud concentrations in its coastal waters. The mud deposits can be quite soft and may liquefy under incoming waves. Subsequently, the liquefied mud damps the incoming waves effectively. This paper presents a simple model to predict wave attenuation over soft (fluid) mud beds. This model is based on the two-layer approach by Gade [Gade, H.G., 1958, Effects of a non-rigid, impermeable bottom on plane surface waves in shallow water, Journal of Marine Research, 16 (2) 61–82.] which is implemented in the standard version of the state-of-the-art wave-prediction model SWAN. Input to the mud wave damping module consists of the extension, thickness, density and viscosity of the liquefied (fluid) mud layer. 相似文献
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Recent debates about the eruptive behavior of mud volcanoes and their activation mechanisms have been driven particularly by the LUSI eruption in Indonesia that resulted in huge commercial and cultural damages. Numerical modeling of mud volcanoes, of which few exist, can provide insight into eruptive behavior and contribute to hazard evaluation. In this paper, we present a simple model to describe fluid escape from an underground reservoir through a conduit, extruded as a mud volcano at the surface. The governing equations result in oscillatory behavior, and we study the influence of changes in rheological properties of surrounding rock and fluid characteristics of the mud on extrusion dynamics. We focus on understanding long-term eruption behavior, flow cycles, and decay factors. Model results can be used to estimate the discharge rates and extruded volume from assumptions on the mud reservoir and conduit, or conversely, the reservoir or conduit properties from discharge rates. 相似文献
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Daniel Jean Stanley 《Marine Geology》1974,16(1):M1-M8
Direct visual observation of the Wilmington Canyon axis by research submersible shows that the fill is a very poorly sorted mix of coarse fragments (pebbles, cobbles) dispersed in a muddy matrix. This facies resembles pebbly mudstone units not infrequently associated with ancient deep marine sequences. Earlier dredge, television and camera surveys reveal the widespread nature of slump deposits on the adjacent canyon walls; this type of failure is the major process in the canyon head in terms of sediment volume displaced. Surprisingly, however, only a thin fill occupies the V-shaped axial channel. It is proposed here that down-wall slumps are transformed to debris flow in the axis, and the latter serves as the canyon head flushing mechanism. 相似文献
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Ａｍｏｄｅｌｏｆｐｒｏｆｉｌｅｅｖｏｌｕｔｉｏｎｏｎｗａｖｅ－ｄｏｍｉｎａｔｅｄｍｕｄｃｏａｓｔＺｈａｎｇＹｏｎｇ，ＹｕＺｈｉｙｉｎｇａｎｄＪｉｎＬｉｕ（ＲｅｃｅｉｖｅｄＪｕｌｙ２３，１９９６；ａｃｃｅｐｔｅｄＯｃｔｏｂｅｒ．．８，１９９６）Ａｂｓｔ... 相似文献
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大弹涂鱼土池育苗技术研究 总被引：8，自引：0，他引：8
在总面积为3 340 m2的4口土池(835 m2/口)进行大弹涂鱼(Boleophthalmus pecti-nirostris(Linnaeus))育苗试验研究。共放养1龄和2龄亲鱼11 000尾,2004年5月16日~5月21日和5月31日~6月4日先后孵出两批仔鱼,每批次的孵化时间持续5~6 d,共孵出仔鱼330×104尾。采用泼洒泥浆、接种轮虫、施肥、调节池水盐度和遮阳控制水温等方法进行仔稚鱼培育,土池育苗取得了突破性进展。初孵仔鱼经过34~53 d的培育,共培育出幼鱼34.76×104尾,幼鱼平均全长23.1 mm,平均体质量100.0 mg,平均成活率10.5%。试验结果表明,大弹涂鱼亲鱼未经性激素注射能在土池洞穴内自然产卵孵化,采取合理的技术措施在土池中进行大弹涂鱼批量育苗是可行的。 相似文献