1 / 25

A.Taheri Tizro(1) , M. Salehzade(2)

Estimation of Hydraulic Properties of Ground water by application of Geoelecterical Method– a case Study in West Iran. A.Taheri Tizro(1) , M. Salehzade(2). (1& 2) Dept. of Water Engineering, College of Agriculture, Razi University, Kermanshah, Iran. Fig. :Index map of Iran.

oren-henry
Télécharger la présentation

A.Taheri Tizro(1) , M. Salehzade(2)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Estimation of Hydraulic Properties of Ground water by application of Geoelecterical Method– a case Study in West Iran A.Taheri Tizro(1) , M. Salehzade(2) (1& 2) Dept. of Water Engineering, College of Agriculture, Razi University, Kermanshah, Iran.

  2. Fig. :Index map of Iran

  3. Fig. Structural Map of Iran Stocklin (1986) has classified the area in between tectonic zone of Zagros formation and Sanandaj- Sirjan zones and considered to be a tectonically active area.

  4. Aims and Scope Evaluation hydraulic characteristicby Litho logical data and pumping test data • The transmissivity of the unconfined aquifers have been computed by solving the Dar-Zarrouk Parameter and was compared with the actual field transmissivity. • Estimation aquifer transmissivity from resistivity data for alluvial aquifers in Kangavar Basin

  5. Table 1 Kangavar aquifer parameters from the field test method

  6. Fig. 1 Geological map of the study area, showing the location of VES Unconsolidated alluvial deposits, underlain by a thick sequence of Mesozoic and Cenozoic formations

  7. BackgroundSince the late 1960s resistivities determined from surface measurements have been used to estimate aquifer properties such as yield, hydraulic conductivity and transmissivity. Three types of activities were used to derive a relation between the geoelectric and hydraulic properties: -Relation between formation factor (F) and hydraulic properties -Relation between formation resistivity () and hydraulic conductivity -Relation between transverse resistance (R) and transmissivity

  8. Material and methods • Acquisition of data and interpretation • From resistivity data, Dar-Zarrouk parameter i.e. transverse unit resistance and longitudinal unit conductance was calculated If prism is isotropic and homogeneous aquifer material having unit cross sectional area and thickness “h” is considered, Darcy’s law and Ohm’s law can be combined (1) Equation (1) was modified by taking into consideration a modified aquifer resistivity

  9. Modification factor is always the ratio of the average aquifer resistivity and the aquifer resistance at a particular location. Equation (1) can be written as (2) are modified conductivity” and “modified Transverse resistance” of the aquifer. assumed to be constant of the aquifer at a reference point is known. The product A corollary of equation (2) can thus be written as: (3) Equation (2) and (3) are useful for computing transmissivity and hydraulic conductivity of the aquifers in porous, homogenous and isotropic media.

  10. Fig. 2 Hydrograph of groundwater table fluctuations in Kangavar basin Average decline in the water table of about 10.4 m during the period 1982–2003

  11. Fig. 3 Contour map showing Electrical conductivity (microsiemens/cm) variation of monitored wells

  12. Result Fig. 4 Selected sounding curves and relevant lithological profiles in the study area: (a) Firooz Abad-Kocha village, and (b) Karkhane village

  13. Fig. 5 -a (Geoelectrical Section AA) The upper layer (resistivity 20–30 ohm.m, thickness 70-250 m) is composed of alluvium mixed with sand and pebbles and is underlain by hard rock formations. At VES2, the decrease in resistivity to 38 ohm.m observed at a depth of about 250 m indicates the presence of weathered and fractured hard rock formations.

  14. Fig. 5-b (Geoelectrical Section BB)

  15. Fig. 5-c (Geoelectrical Section CC)

  16. Fig. 7 Fig.6 The Kσ' distinguished zones in the study area

  17. Fig. 7 Contour map showing transmisivity variation in the basin.

  18. Fig. 8 Relation between transmissivity (T) and transverse resistance (R)

  19. Fig. 9 Relation between transmissivity (T) and modified transverse resistance (R')

  20. Fig. 10 Relation between field hydraulic conductivity and computed hydraulic conductivity

  21. Conclusions -The use of VESs provide an inexpensive technique for characterizing the geological setting, as well the hydrogeological conditions (geometry of the aquifer systems) of the basin. -The closeness of hydraulic conductivity values obtained from pumping tests and grain size analysis and those estimated from VES interpretations is a good indication of the reliability of this method -Based on calculated values of hydraulic parameters it is concluded that the north eastern part of the study area is very important with respect to favourable hydrogeological conditions -Direct relation between aquifer transmissivity and the modified transverse resistance of alluvial aquifers is a reliable method that can be utilised for the estimation of transmissivity using geoelectrical methods

  22. Many Thanks

More Related