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1.
The influence of faults in basin-fill deposits on land subsidence,Las Vegas Valley,Nevada, USA 总被引：1，自引：0，他引：1
Thomas J. Burbey 《Hydrogeology Journal》2002,10(5):525-538
The role of horizontal deformation caused by pumping of confined-aquifer systems is recognized as contributing to the development
of earth fissures in semiarid regions, including Las Vegas Valley, Nevada. In spite of stabilizing water levels, new earth
fissures continue to develop while existing ones continue to lengthen and widen near basin-fill faults. A three-dimensional
granular displacement model based on Biot's consolidation theory (Biot, MA, 1941, General theory of three-dimensional consolidation.
Jour. Applied Physics 12:155–164) has been used to evaluate the nature of displacement in the vicinity of two vertical faults.
The fault was simulated as (1) a low-permeability barrier to horizontal flow, (2) a gap or structural break in the medium,
but where groundwater flow is not obstructed, and (3) a combination of conditions (1) and (2). Results indicate that the low-permeability
barrier greatly enhances horizontal displacement. The fault plane also represents a location of significant differential vertical
subsidence. Large computed strains in the vicinity of the fault may suggest high potential for failure and the development
of earth fissures when the fault is assumed to have low permeability. Results using a combination of the two boundaries suggest
that potential fissure development may be great at or near the fault plane and that horizontal deformation is likely to play
a key role in this development.
Electronic Publication 相似文献
2.
Toshiharu Misonou Hisafumi Asaue Tohru Yoshinaga Yuta Matsukuma Katsuaki Koike Jun Shimada 《Hydrogeology Journal》2013,21(7):1593-1603
Groundwater flow exerts a crucial control on the boundary between the sea and freshwater and is thus a key factor for preserving groundwater resources and preventing seawater intrusion in coastal areas. Although it is highly probable that geological faults in coastal areas affect groundwater flow patterns, the effect has not been described yet in detail. This study is aimed at detecting and imaging groundwater flow and its temporal change around a fault in a coastal area through resistivity and chargeability distributions using electrical sounding. The Okoshiki area in central Kyushu, southwest Japan, was selected as a case study area, because of the presence of Kamiouda Fault. The measurements were conducted along six lines of both parallel and perpendicular orientations to the coastline. A feature suggesting a fault zone was evident on two lines. Through the temporal change of resistivity, movement and mixing processes of the seawater and freshwater during the ebb, low and flood tides were interpreted. A conceptual model of the processes was constructed in which a fault zone and the configuration of bedrock are dominant elements by acting as a selective path and a barrier to the groundwater flow, respectively. 相似文献
3.
Groundwater flow dynamics in the complex aquifer system of Gidabo River Basin (Ethiopian Rift): a multi-proxy approach 总被引：2，自引：0，他引：2
Abraham Mechal Steffen Birk Martin Dietzel Albrecht Leis Gerfried Winkler Aberra Mogessie Seifu Kebede 《Hydrogeology Journal》2017,25(2):519-538
Hydrochemical and isotope data in conjunction with hydraulic head and spring discharge observations were used to characterize the regional groundwater flow dynamics and the role of the tectonic setting in the Gidabo River Basin, Ethiopian Rift. Both groundwater levels and hydrochemical and isotopic data indicate groundwater flow from the major recharge area in the highland and escarpment into deep rift floor aquifers, suggesting a deep regional flow system can be distinguished from the shallow local aquifers. The δ18O and δ2H values of deep thermal (≥30 °C) groundwater are depleted relative to the shallow (<60 m below ground level) groundwater in the rift floor. Based on the δ18O values, the thermal groundwater is found to be recharged in the highland around 2,600 m a.s.l. and on average mixed with a proportion of 30 % shallow groundwater. While most groundwater samples display diluted solutions, δ13C data of dissolved inorganic carbon reveal that locally the thermal groundwater near fault zones is loaded with mantle CO2, which enhances silicate weathering and leads to anomalously high total dissolved solids (2,000–2,320 mg/l) and fluoride concentrations (6–15 mg/l) exceeding the recommended guideline value. The faults are generally found to act as complex conduit leaky barrier systems favoring vertical mixing processes. Normal faults dipping to the west appear to facilitate movement of groundwater into deeper aquifers and towards the rift floor, whereas those dipping to the east tend to act as leaky barriers perpendicular to the fault but enable preferential flow parallel to the fault plane. 相似文献
4.
Using saline tracers to evaluate preferential recharge in fractured rocks,Floyd County,Virginia, USA
Potassium chloride (KCl) and potassium bromide (KBr) tracers were used to explore the role of geologic structure on groundwater recharge and flow at the Fractured Rock Research Site in Floyd County, Virginia, USA. Tracer migration was monitored through soil, saprolite, and fractured crystalline bedrock for a period of 3 months with chemical, physical, and geophysical techniques. The tracers were applied at specific locations on the ground surface to directly test flow pathways in a shallow saprolite and deep fractured-rock aquifer. Tracer monitoring was accomplished with differential electrical resistivity, chemical sampling, and physical monitoring of water levels and spring discharge. KCl, applied at a concentration of 10,000 mg/L, traveled 160 m downgradient through the thrust fault aquifer to a spring outlet in 24 days. KBr, applied at a concentration of 5,000 mg/L, traveled 90 m downgradient through the saprolite aquifer in 19 days. Tracer breakthrough curves indicate diffuse flow through the saprolite aquifer and fracture flow through the crystalline thrust fault aquifer. Monitoring saline tracer migration through soil, saprolite, and fractured rock provided data on groundwater recharge that would not have been available using other traditional hydrologic methods. Travel times and flowpaths observed during this study support preferential groundwater recharge controlled by geologic structure. 相似文献
5.
John P. Gannon Thomas J. Burbey Robert J. Bodnar Joseph Aylor 《Hydrogeology Journal》2012,20(1):45-60
The largest undeveloped uranium deposit in the United States, at Coles Hill, is located in the Piedmont region of Pittsylvania County, south-central Virginia, and is hosted in crystalline rocks that are adjacent to and immediately west of Chatham Fault, which separates these crystalline rocks from the metasedimentary rocks of the Danville Triassic Basin (in the east). Groundwater at the site flows through a complex network of interconnected fractures controlled by the geology and structural setting. The role of Chatham Fault in near-surface (<??200?m) groundwater flow is examined using electrical resistivity profiling, borehole logging, a pumping test, groundwater age dating and water chemistry to determine if the fault represents a permeability barrier or conduit for groundwater flow. The volumetric flow per unit width flowing eastward across the fault is estimated at 0.069?C0.17?m2/day. Geochemical data indicate that groundwater in the granitic crystalline rocks represents a mixture of modern and old water, while the Triassic basin contains a possible deeper and older source of water. In regions with shallow water tables, mine dewatering during operation presents significant mining costs. The study??s results yield important information concerning the effect that Chatham Fault would have on groundwater flow during Coles Hill mining operations. 相似文献
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Industrial sites present a challenge to the hydrogeological delineation of pollution sources and their impacts. When large-scale
geologic structures such as grabens exist on such sites, these can have a significant impact on the hydrology and water quality
distribution. At the site investigated, geophysical techniques, standard hydrogeological approaches and hydrochemical characterisation
(with methods such as depth-profiling and isotopes) were used to determine the impact of a graben structure and the hydrogeological
properties and consequent water quality distribution. Zones of high conductivity, corresponding with available data, were
identified from the geophysical investigation and subsequent pumping tests in the area. Through hydrochemical characterisation,
including isotopes, it was determined that the fault zone acts as a barrier for groundwater flow and is thus the reason for
the lower levels of pollutants in groundwater beyond this feature. However, the surface water flow is not restricted by these
zones, and contributes significantly to the flow and salt loads at the discharge point. The study showed that graben structures
are important controls on the movement of contaminants, and that the effect of such geological features on groundwater quality
distribution must be investigated using multiple methodologies to construct a feasible conceptual model of the interactions. 相似文献
9.
A hydrogeological study was completed within a sub-catchment of the Zerka River drainage basin, in western Jordan. The system
is characterized by anticlinal bending with an axis trending SSW–NNE and plunging a few degrees in the SSW direction. The
anticlinal structure diverts groundwater flow towards the SSW while the strike-slipe faults cause the groundwater to diverge
where the fault is perpendicular to the groundwater flow lines, and to converge where the fault is parallel to the groundwater
flow lines. A direct relationship was found between the location of springs and the type of groundwater flow with regard to
the amount of discharge wherein large spring discharges are located in zones of converging groundwater flow lines. In areas
where faults are not abundant, the groundwater retention time in the aquifers is long and a zonation of the electrical conductivity
was detected due to mineral dissolution. By controlling groundwater flow, the anticlinal setting produces three genetic groups
of groundwater flow systems: (1) alkaline–earth alkaline water which is predominately a bicarbonate-type composition, (2)
alkaline–earth alkaline water which is predominately bicarbonate–sulfate, and (3) alkaline–earth alkaline water with a high
alkaline component. 相似文献
10.
Aleksandra Kiecak Grzegorz Malina Ewa Kret Tadeusz Szklarczyk 《Environmental Earth Sciences》2017,76(6):248
Selection of effective groundwater remediation scenarios is a complex issue that requires understanding of contaminants’ transport processes. The effectiveness of cleanup measures may be verified by fate and transport numerical modeling. The goal of this work was to present the usefulness of fate and transport modeling for planning, verification and fulfillment of effective groundwater remediation methods. Selection methodology was developed, which is based on results of numerical flow and transport modeling. A field site located in south-east Poland was selected as a case study, in which groundwater contamination of trichloroethene and tetrachloroethene was detected. The results indicated that “pump and treat” was the most effective among the studied remediation methods, followed by permeable reactive barrier and in situ chemical oxidation. Natural attenuation-based remediation was demonstrated to be the least suitable, as it requires the longest time to reach predefined remediation goals, principally due to low sorption capacity and unfavorable hydrogeochemical conditions for biodegradation. Fate and transport numerical modeling allowed simulating different remediation strategies, and thus the decision-making process was facilitated. 相似文献
11.
Jeonghoon Lee Byeongju Jung Jun-Mo Kim Kyung-Seok Ko Ho-Wan Chang 《Environmental Earth Sciences》2011,63(4):763-770
Understanding groundwater flow and chemical transport is crucial for operating underground storage caverns. Groundwater flow
in the study area is mainly affected by cavern operating conditions, and groundwater chemistry in the study area is modified
by disinfection activities for removing possible biological clogging and by mixing with cement pore water. It is significant
to discern these two effects because wells affected by the disinfection activities, in particular, may have hydrological connections
with water curtains in which disinfectant water was injected to remove the biological clogging. Concentration of tritium (3H) and helium isotopes (4He), and groundwater chemical compositions were used to confirm that there are hydrological connectivities between the water
curtain and the well. Groundwater along the fault areas contains low total dissolved solid (TDS) and high 3H, suggesting that the faults may act as fast flow conduits, which is not inconsistent with previous studies. Certain diagnostic
conditions (high concentrations of Na+, Cl− and TDS and high pH) are presumed by the effect of disinfection activity, indicating that there are hydrological connections
between the water curtain and the wells. This hypothesis is valid in YK2U and YK2L, but is not in YK12L, implying a closed
system or an immobile water to explain the isotopic results. 相似文献
12.
天山北麓玛纳斯河流域山问洼地位于低山丘陵区山前坳陷带的南部，该区褶皱、断裂、近NS向次级张性断裂与平移构造以及山间洼地的第四系沉积物发育．山区地表水流经该段入渗，加之南部中山区的侧向补给形成山间洼地地下水库．正确认识玛纳斯河流域山间洼地地下水库的形成机理并对其进行合理的开发利用，对解决玛纳斯河流域季节性缺水及枯水年缺水有重要意义．笔应用构造及地表水由山区水站至山口渠首站实测流量损失的研究成果，揭示了玛纳斯河流域山间洼地地下水库的形成及调蓄作用，并概算了补给量，为今后开发利用山间洼地地下水库水资源提供了依据． 相似文献
13.
拒马源泉群作为拒马河的源头,受到了较多专家和学者的关注。但这些研究多集中在地下水的水化学、水位动态、泉流量等特征上,对地下水氢氧同位素特征的分析几乎没有,且对北海泉的成因解释多为粗略的定性概述。为了说明涞源北盆地地下水的氢氧同位素特征,详细揭示北海泉的形成模式,首次系统地采集了不同含水岩组的地下水样品,测定了水样的氢氧同位素组分。结果表明:样品点δD和δ18O值均落在区域大气降水线上或附近,大气降水是研究区地下水的主要补给来源;白云岩、灰岩含水岩组高程效应较明显,径流途径长,松散含水层径流途径短,受蒸发作用较强;白云岩、灰岩含水岩组和松散含水层氘盈余d值分别为6.0‰～11.6‰、4.2‰～11.2‰、3.8‰～8.0‰,较大气降水大部分偏小,表明岩溶水和松散孔隙水经历了不同的流动过程;白云岩、灰岩含水岩组从补给区向排泄区各自流动过程中,在小西庄、香炉屯村附近断裂带发生沟通混合,然后在向盆地中心径流过程中受断层阻水上升,上升过程中又接受了松散孔隙水的补给,最后在松散岩层中出露成泉,形成北海泉。在孔隙水混入前,两者的平均补给比例大约为48.4%～57.6%和42.4%～51.6%。 相似文献
14.
Structural geology controls on groundwater flow: Lembang Fault case study, West Java, Indonesia 总被引：2，自引：1，他引：1
Robert M. Delinom 《Hydrogeology Journal》2009,17(4):1011-1023
Field evidence has shown that Lembang Fault (West Java, Indonesia) can act as a groundwater flow barrier. There are outcrops along the footwall comprising consolidated brecciated rock with very low permeability, springs and hot springs occurring along down-thrown hanging-wall rock adjacent to the fault, and a high permeability layer of old and young Tangkuban Parahu eruptive materials (hanging wall) juxtaposed against the low permeability of the older volcanic layer of Bukit Tunggul unit (footwall). Two different environmental tracers were utilized in the study: electrical conductivity measurement and stable isotope analysis. Hydraulic head was measured at some wells along the fault and water electrical conductivity measurements were carried out in a small catchment, the upper part of Cikapundung River basin, which is located just north of Bandung City. Water samples for stable isotope composition analysis were taken from 19 observation wells distributed randomly inside the basin. All analysis data lead to the recognition that Lembang Fault blocks the groundwater flow. No indication was found for water being recharged at higher elevation in the northern part of Bandung Basin, which means the recharged water in Mount Tangkuban Parahu area does not reach Bandung Plain. 相似文献
15.
大型复杂滑坡受断裂构造的水力补给作用,常发育丰富的地下水。断裂构造水力补给主要受区域水文地质条件控制,具有水质、水量较为稳定等特点,对滑坡稳定性影响巨大且具有长期性。目前,有关断裂构造对滑坡的水力补给作用的研究成果较少,缺乏断裂构造对滑坡水力补给作用类型、形成条件等共性规律的系统性研究。本文通过分析研究国内断裂构造水力补给滑坡的典型实例,根据断裂构造的分布位置、力学性质及其对滑坡地下水的补给方式和水力联系等,将断裂构造对滑坡的水力补给类型划分为边界补给型、滑床补给型及复合型3种类型,分析了地下水对滑坡的4种作用机理——滑带孔隙水压力增高、滑床承压水顶托、滑带黏土矿物遇水膨胀及滑带化学溶蚀。研究成果对于揭示滑坡地下水运移规律、定量评价地下水对滑坡的作用及合理确定地下截排水设计等具有重要指导价值。 相似文献
16.
This study used optical brighteners (OB) released from septic systems to show that groundwater flow direction is largely controlled
by the structural framework in a faulted karst groundwater system. Effective protection of groundwater resources requires
that groundwater systems are adequately characterized and source water protection areas (SWPA) are developed for drinking
water wells. Karst aquifers are among the most sensitive to contamination due to high recharge rates, and among the most difficult
aquifers to characterize due to heterogeneity, and anisotropy. Because septic systems may be used to treat wastewater within
SWPAs for karst aquifers there is a need to characterize these groundwater systems using tracers. The objective of this study
was to characterize groundwater flow in a faulted portion of the Edwards aquifer in Bexar County, Texas using OB that are
released as incidental tracers from septic systems. This study included measurement of water levels, sampling of groundwater
and surface water, analysis for OB, and spatial analysis in a GIS. Results show that OB intensities were highest to the southwest
of the septic area, a direction that is sub-parallel to the fault and fracture orientation and nearly perpendicular to the
hydraulic gradient. This indicates that movement of OB, solutes, or non-aqueous liquids/solids in a faulted karst system can
be largely controlled by fault/fracture orientation and structural relay ramps. 相似文献
17.
根据地下水地球化学特征，在福州盆地划分出４个溶质系统，ＥＮＥ断层系列浅循环溶质系统，洪积扇带溶质系统，古河道带溶质系统及ＮＮＷ断层带深循环溶质系统。文中论述了各系统的形成过程及其在开采条件下的变化。 相似文献
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Groundwater modelling is widely used as a management tool to understand the behaviour of aquifer systems under different hydrological stresses, whether induced naturally or by humans. The objective of this study was to assess the effect of a subsurface barrier on groundwater flow in the Palar River basin, Tamil Nadu, southern India. Groundwater is supplied to a nearby nuclear power plant and groundwater also supplies irrigation, industrial and domestic needs. In order to meet the increasing demand for groundwater for the nuclear power station, a subsurface barrier/dam was proposed across Palar River to increase the groundwater heads and to minimise the subsurface discharge of groundwater into the sea. The groundwater model used in this study predicted that groundwater levels would increase by about 0.1?C0.3?m extending out a distance of about 1.5?C2?km from the upstream side of the barrier, while on the downstream side, the groundwater head would lower by about 0.1?C0.2?m. The model also predicted that with the subsurface barrier in place the additional groundwater requirement of approximately 13,600?m3/day (3 million gallons (UK)/day) can be met with minimum decline in regional groundwater head. 相似文献
20.
Constraining fault-zone hydrogeology through integrated hydrological and geoelectrical analysis 总被引：1，自引：1，他引：0
Lyndsay B. Ball Shemin Ge Jonathan Saul Caine André Revil Abderrahim Jardani 《Hydrogeology Journal》2010,18(5):1057-1067
The hydrogeologic influence of the Elkhorn fault in South Park, Colorado, USA, is examined through hydrologic data supplemented by electrical resistivity tomography and self-potential measurements. Water-level data indicate that groundwater flow is impeded by the fault on the spatial scale of tens of meters, but the lack of outcrop prevents interpretation of why the fault creates this hydrologic heterogeneity. By supplementing hydrologic and geologic data with geoelectrical measurements, further hydrogeologic interpretation is possible. Resistivity profiles and self-potential data are consistent with the interpretation of increased fracturing within 70 m of the fault. Further interpretation of the fault zone includes the possibility of a vertical groundwater flow component in a fractured and relatively high permeability damage zone and one or more relatively low permeability fault cores resulting in a conduit-barrier behavior of the fault zone at the meter to tens-of-meters scale. Calculated hydraulic heads from the self-potential data reveal additional complexity in permeability structure, including a steeper hydraulic gradient immediately west of the interpreted fault trace than suggested by the well data alone. 相似文献