Isotopic constraints of vein carbonates on fluid sources and processes associated with the ongoing brittle deformation within the accretionary wedge of Taiwan   总被引：1，自引：0，他引：1  

Pei‐Ling Wang  Jia‐Jing Wu  En‐Chao Yeh  Sheng‐Rong Song  Yue‐Gau Chen  Li‐Hung Lin 《地学学报》2010,22(4):251-256

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Numerical modeling of coupled fluid flow and thermal and reactive biogeochemical transport in porous and fractured media     

Gour-Tsyh Yeh  Yilin Fang  Fan Zhang  Jiangtao Sun  Yuan Li  Ming-Hsu Li  Malcolm D. Siegel 《Computational Geosciences》2010,14(1):149-170

Subsurface contamination problems of metals and radionuclides are ubiquitous. Metals and radionuclides may exist in the solute phase or may be bound to soil particles and interstitial portions of the geologic matrix. Accurate tools to reliably predict the migration and transformation of these metals and radionuclides in the subsurface environment enhance the ability of environmental scientists, engineers, and decision makers to analyze their impact and to evaluate the efficacy of alternative remediation techniques prior to incurring expense in the field. A mechanistic-based numerical model could provide such a tool. This paper communicates the development and verification of a mechanistically coupled fluid-flow thermal-reactive biogeochemical-transport model where both fast and slow reactions occur in porous and fractured media. Theoretical bases, numerical implementations, and numerical experiments using the model are described. A definition of the “rates” of fast/equilibrium reactions is presented to come up with a consistent set of governing equations. Two example problems are presented. The first one is a reactive transport problem which elucidates the non-isothermal effects on heterogeneous reactions. It also demonstrates that the rates of fast/equilibrium reactions are not necessarily greater than that of slow/kinetic reactions in the context of reactive transport. The second example focuses on a complicated but realistic advective–dispersive–reactive transport problem. This example exemplifies the need for innovative numerical algorithms to solve problems involving stiff geochemical reactions. It also demonstrates that rates of all fast/equilibrium reactions are finite and definite. Furthermore, it is noted that a species-versus-time curve cannot be used to characterize the rate of homogeneous fast/equilibrium reaction in a reactive transport system even if one and only one such reaction is responsible for the production of this species.  相似文献   

Reply to Comment on “Analysis of pumping test data for determining unconfined-aquifer parameters: Composite analysis or not?”: paper published in Hydrogeology Journal (2009) 17:1133–1147, by Hund-Der Yeh and Yen-Chen Huang     

Hund-Der Yeh  Yen-Chen Huang 《Hydrogeology Journal》2010,18(8):1979-1981

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The effect of the variation of river water levels on the estimation of groundwater recharge in the Hsinhuwei River,Taiwan   总被引：1，自引：1，他引：0  

Jung-Wei Chen  Hsun-Huang Hsieh  Hsin-Fu Yeh  Cheng-Haw Lee 《Environmental Earth Sciences》2010,59(6):1297-1307

Land subsidence is a serious problem in Taiwan’s Yunlin area due to groundwater overpumping. There are safety risks in the high-speed railway structures in the areas of Siluo, Huwei, Tuku, and Yuanchang towns that run from north to south in the Yunlin area. Therefore, it is important to increase the groundwater recharge and to remedy the land subsidence in this area. The purpose of this study is to use the stream-flow estimation model (SF) and the groundwater flow numerical software MODFLOW (MF) to estimate the stream infiltration with consideration to the variation of the river water level in the Hsinhuwei River. The Ferris analytical model (FA) and MF are used to estimate the increased stream infiltration after the water level of the river rises. The hydraulic parameters required for each model are obtained from field observations and laboratory experiments. The results indicate that the assessment of the stream infiltration obtained through the SF and MF models are 264.2 × 10⁴ and 170.9 × 10⁴ m³/year, respectively. When the river water level increases by about 2.5 m, the annual stream infiltration obtained through the FA and MF models significantly increases by 31.6 × 10⁴ and 26.4 × 10⁴ m³/year, respectively. Taken together, the stream storages estimated using these two models indicate that an increasing efficiency of groundwater recharge is within the range of 10.0–18.5%.  相似文献   

Copula‐based flood frequency (COFF) analysis at the confluences of river systems     

Cheng Wang  Ni‐Bin Chang  Gour‐Tsyh Yeh 《水文研究》2009,23(10):1471-1486

Many civil infrastructures are located near the confluence of two streams, where they may be subject to inundation by high flows from either stream or both. These infrastructures, such as highway bridges, are designed to meet specified performance objectives for floods of a specified return period (e.g. the 100 year flood). Because the flooding of structures on one stream can be affected by high flows on the other stream, it is important to know the relationship between the coincident exceedence probabilities on the confluent stream pair in many hydrological engineering practices. Currently, the National Flood Frequency Program (NFF), which was developed by the US Geological Survey (USGS) and based on regional analysis, is probably the most popular model for ungauged site flood estimation and could be employed to estimate flood probabilities at the confluence points. The need for improved infrastructure design at such sites has motivated a renewed interest in the development of more rigorous joint probability distributions of the coincident flows. To accomplish this, a practical procedure is needed to determine the crucial bivariate distributions of design flows at stream confluences. In the past, the copula method provided a way to construct multivariate distribution functions. This paper aims to develop the Copula‐based Flood Frequency (COFF) method at the confluence points with any type of marginal distributions via the use of Archimedean copulas and dependent parameters. The practical implementation was assessed and tested against the standard NFF approach by a case study in Iowa's Des Moines River. Monte Carlo simulations proved the success of the generalized copula‐based joint distribution algorithm. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Investigation of non-linear site amplification at two downhole strong ground motion arrays in Taiwan     

Kuo-Liang Wen  Igor A. Beresnev  Yeong Tein Yeh 《地震工程与结构动力学》1995,24(3):313-324

Non-linear seismic response of soil is studied by comparing the spectral ratios of surface to downhole horizontal accelerations on weak and strong motion. Data from two boreholes are analysed. One is drilled in the alluvial deposits in the south–west quadrant of the SMART 1 array. The second one penetrates Pleistocene terrace deposits in the northern part of the SMART2 array. Observed weak and strong motion spectral ratios are compared with the theoretical ones predicted by the geotechnical soil model which postulates a hysteretic constitutive law. A significant non-linear response is found at the first site for the events with surface peak acceleration exceeding roughly 0–15g. Deamplification of the strong motion occurred in the frequency range from approximately 1 to 10 Hz. The maximum observed difference between the average weak and strong motion amplification functions of an 11 m-thick near-surface stratum is a factor of 2–3. Nonlinear response characteristics are in qualitative agreement with the model. An additional corollary is that the amplification function calculated from the shear wave coda is equivalent to the average amplification calculated over the ensemble of small earthquakes. No statistically significant non-linear response is detected on the second array, that is tentatively accounted for by the stiffer soil conditions and weaker accelerations achieved at the SMART2 site. The results indicate that the non-linear amplification can be detectable at certain soil conditions above a threshold acceleration level.  相似文献   

骨灰－伊利石－高岭石体系假相图的研究          下载免费PDF全文

戴长禄  张振禹  叶大年  吴美清  刘蔚玲  郭伯芝 《地质科学》1994,(2)

采用骨灰、伊利石粘土和高岭石粘土作为端元组分，并根据ＤＴＡ、热台显微镜、互ＲＤ方法测定的数据，组成了这个三元体系的假相图。依据假相图讨论了该体系的热相变特征以及有关骨灰瓷工艺学问题。  相似文献   

Hydrogen and carbon isotopes of petroleum and related organic matter     

Hsueh-Wen Yeh  Samuel Epstein 《Geochimica et cosmochimica acta》1981,45(5):753-762

$\text{D}\text{H}$ and ${}^{13}\text{C}{}^{12}\text{C}$ ratios were measured for 114 petroleum samples and for several samples of related organic matter. δD of crude oil ranges from ?85 to ?181‰, except for one distillate (?250‰) from the Kenai gas field; δ¹³C of crude oil ranges from ?23.3 to ?32.5‰, Variation in δD and δ¹³C values of compound-grouped fractions of a crude oil is small, 3 and 1.1%., respectively, and the difference in δD and δ¹³C between oil and coeval wax is slight. Gas fractions are 53–70 and 22.6–23.2‰ depleted in D and ¹³C, respectively, relative to the coexisting oil fractions.The δD and δ¹³C values of the crude oils appear to be largely determined by the isotopic compositions of their organic precursors. The contribution of terrestrial organic debris to the organic precursors of most marine crude oils may be significant.  相似文献   

结构光性矿物学研究——论无水碳酸盐的折射度          下载免费PDF全文

曾荣树  叶大年 《地质科学》1980,15(1):43-49

研究矿物的晶体结构与其光学性质之间的关系,这是结构光性矿物学重要的研究内容。如何把矿物晶体结构中原子的性质及相互之间的关系应用到晶体光学中,有效地定量地解释矿物的光学参数,从而又推动晶体光学进一步发展,这是矿物学家所共同关心的问题。早在1924年布拉格就注意到方解石与文石光性的差异,并用晶体内部电场的理论进行解释。帕伯斯特(A.Pabst,1973,1974)在研究两个碳酸盐矿物的折射率时,根据布拉格的方法,计算了它们的折射度,得到了满意的结果。叶大年(1974)在论述具有氖型结构离子的化合物的折射率时,指出矿物的折射率取决于电子层结构和核电荷,而不是取决于原子量。  相似文献   

Earthquake strong motions recorded by a large near-source array of digital seismographs     

B. A. Bolt  Y. B. Tsai  K. Yeh  M. K. Hsu 《地震工程与结构动力学》1982,10(4):561-573

Specially designed arrays of strong-motion seismographs near to the earthquake source are required for seismological and engineering studies of the generation and near-field properties of seismic waves. The first such large digital array, called SMART 1 (with radius 2 km and 37 accelerometers), to record substantial ground motion (up to 0·24g horizontal acceleration) became operational in late 1980 in a highly seismic region of Taiwan. During the first 6 months of operation, SMART 1 recorded nine earthquakes with magnitudes ranging from M_L 3·8 to 6·9. Three were located directly below the array at focal depths of 59 to 76 km. The remaining six had shallow depths and epicentral distances from 7 to 193 km. Digital records from 27 three-component accelerographs were obtained from a magnitude 6·9 (M_L) local earthquake on 29 January 1981. Representative measurements are described of seismic wave coherency and power spectrum as a function of wave number, frequency, azimuth of propagation and wave type. Acceleration waveforms varied significantly across the array for each event. On average, peak acceleration of horizontal components was about three times that of the vertical component. Relative spectral changes from earthquake to earthquake were large.  相似文献