D1.1: Report describing the site(s) for applying the proposed methodology.
The site selection procedure was initiated in the kick off meeting held in Chania, Greece between 17 and 18 February 2012. Eleven participants representing the three partners: Technical University of Crete, Ankara University and Greifswald University were present. Τhe evaluation system developed for the needs of the site selection was based on 15 factors extracted from the three criteria initially set for WP1a. Each factor is given a grade on a scale to 5, where the highest grade (5) denotes most propitious conditions for the site selection, while zero value denotes that the site is inappropriate for the application of developed methodology. A total of 8 sites were proposed from the partners. These sites were studied, discussed and evaluated in the kick off meeting, using the evaluation system described above. Tybaki in Greece and Bafra in Turkey were the sites finally selected for the application of the proposed methodology.
D1.2: 2D and 3D detailed geological and hydrogeological maps of the selected studied area(s).
This deliverable deals with the construction of the geological and hydrogeological maps of Tybaki and Bafra Plain sites in order to support the geological and hydrogeological studies of the existing phenomenon of seawater intrusion in the aforementioned sites. In order to construct a 3D geological model for both sites a GIS geological database (ArcGIS®) was developed using all the available data. The limited capabilities in handling real 3D data with GIS packages, is overcome with the use of a 3D geomodeler software. So, the GIS database of Tybaki area was transferred into the geomodeler sofware (RockWorks15) to be integrated into the 3D modelling process in order to generate more complete and realistic models. Several types of data were imported into the database, such as topographical, surface-geological data, borehole descriptions and geophysical measurements. Topographical data comprise a digital elevation model that was produced from point elevation data acquired over a regular grid of 5m x 5m cell dimensions for Tybaki and a digital elevation model that was produced from a contour elevation map for Bafra (DSI, 1985). In addition, surface geological data comprise digitized formation boundaries and faults. The digitizing process presupposes the re-projection of all data in a common and synchronous coordinate system. Furthermore, a large number of boreholes were used in terms of lithologic and stratigraphic descriptions. Finally, existing geophysical data comprise 71 VES measurements, 89 TEM measurements and 260 RTM measurements for Tybaki and 418 VES measurements for Bafra.
D1.3: Petrophysical parameters of the studied area(s).
This deliverable deals with the hydraulic parameters of the water bearing formations in Tympaki Basin and the hydrochemical data in Bafra plain, Samsun, Turkey in order to support the geological and hydrogeological studies of the existing phenomenon of seawater intrusion in the aforementioned sites.
D2.1: Joint inversion code for 2D seismic refraction, electromagnetic and electric data.
Development of an electric, electromagnetic and seismic data joint inversion algorithm, dedicated to salt water intrusion imaging. A seismic refraction and electric data joint inversion algorithm using the cross gradients constraint has already been developed at the Applied Geophysics Laboratory of the Technical University of Crete (TUC), while an electric and electromagnetic data joint inversion algorithm has been developed at the Ankara University. These two algorithms were combined in order to achieve a powerful tool for the joint inversion of the three above mentioned types of geophysical data. Synthetic resistivity and velocity models were created for studying the efficiency of the inversion algorithm. The individual inversion reproduced either the geoelectrical test model or the seismic model satisfactorily, which was not the case for the other model. In the models derived from the joint inversion of the DCR, RMT and seismic data the resolution of both the resistivity and the seismic velocity models is improved as the geological structures are better delineated. The outcome of joint inversion of the Tybaki data consists of a geoelectrical section with increased resolution regarding its shallow part, while for Bafra joint inversion increased the lateral resolution of the seismic model. The developed algorithm provides a powerful tool for more valid and easier interpretation of the geophysical sections, by obtaining a common geophysical model for all collected geophysical data.
D2.2: Raw geophysical data and report with the processed data and interpreted results.
This deliverable deals with the geophysical surveys at Tybaki, Crete, Greece and Bafra Plain, Turkey sites which were conducted in order to support the geological and hydrogeological studies of the existing phenomenon of seawater intrusion in the aforementioned sites.
The available information for Tybaki, consisted of data from geophysical surveys which have been conducted in the framework of the MEDIS project (MEDIS, 2005) and FAO project (FAO, 1969, 1972). A geophysical investigation during the MEDIS project was carried out by employing three geophysical methods, namely transient electromagnetics (TEM), vertical electrical soundings (VES) and radiomagnetotellurics (RMT), while the FAO project involved the VES method. Existing geoelectrical data at Bafra consisted of a large number of VES in sections (DSI, 1985).
The processed data acquired within the framework of the ClearWater project and interpreted results of the geophysical investigation are presented. This investigation consisted of Vertical Electrical Soundings (VES), Electrical Resistivity Tomography (ERT), Seismic Tomography (ST), Time Domain Electromagnetic (TDEM) (or Transient Electromagnetic – TEM as they are also named) and Radiomagnetotellurics (RMT) surveys at both the sites of interest. Geophysical data processing consisted of separate processing for each geophysical method, as well as joint inversion of ERT, ST and RMT data. A calibration with nearby boreholes data and geological mapping data was utilized for the final interpretation results.
D3.1: A small scale tank model to simulate the geological and hydrogeological conditions of the studied area(s).
For the application of a small-medium monitoring controlled laboratory experiment, a tank of 1 cubic meter (1mx1mx1m) was constructed using a high performance 1 cm thick plexiglass with high transparency and strength. The constructed tank was also inserted in a metal frame able to support the whole assembly of inner forces and pressures generated by the tank and containing materials. The construction was made to accept a maximum load of about 4000X10 m/s2 or 40kN. Four boreholes with twelve electrodes each were constructed. The boreholes were constructed by using high density PVC tube material. Electrodes were steal screws with 5 cm interval (12 electrodes on each tube). The distance between two neighboring tubes was 30cm and the distance from the sides of the tank was 35 cm and the last (the deeper) electrodes were installed at the depth of 0.582 cm (0.418 m from the bottom) Copper wire was used for the connection of the electrodes with the data logging device. After the construction of the borehole electrodes, the tubes were filled with silicone for isolating the electrodes from each other and avoiding current leakages (short circuit). The position of each electrode was projected and marked on the sides of plexiglass in order the position of each electrode to be able to be compared with the water level.
Three different stages of the tank construction. (Left) Simulation of the tank construction, (middle) the plexiglass tank constructed before placing it within the metal base and (right) the plexiglass tank in the metal base with the four boreholes electrode configuration.
D3.2: Water flow model of the studied area(s).
This deliverable deals with the water flow model of Tybaki, Greece and Bafra Plain, Turkey sites in order to support the geological and hydrogeological studies of the existing phenomenon of seawater intrusion in the aforementioned sites. The hydrogeological outline of both sites and the results of the water flow modeling are presented.
D3.3: Updated GIS database with the new hydrogeological information.
Due to the heterogeneity of aquifers, representing the spatial distribution of the parameters and variables that are involved in the constitutive laws, describing the simulated processes created a huge data volume. Effective managing of these data involved GIS. All the available and the newly acquired data were integrated in a GIS database. Moreover, GIS simplified significantly the implementation of data management tasks of model building and model calibration. The integration of GIS and groundwater models aided in maintaining and assessing management options (WP4).
D4: Report for groundwater management plan in the studied area(s).
D5.1: Final report of the proposed project results including at least two scientific publications (or accepted submissions for publications) and one presentation at conference (or accepted submissions for presentation).
Kourgialas N., Dokou Z., Karatzas G.P., Panagopoulos G., Soupios, P., Vafidis, A., Manoutsoglou E., Schafmeister M., (2015), Saltwater intrusion in an intensively irrigated agricultural area: combining density-dependent modeling and geophysical methods, Environmental Earth Sciences, submitted.
Vafidis, A., P. Soupios, G. Kritikakis, N. Andronikidis, N. Economou, H. Hamdan, E. Manoutsoglou, E. Steiakakis, E. Candansayar, M.T. Schafmeister and M. Kritsotakis, (2014), Salt Water Intrusion Imaging at Tybaki (Greece) Using Geophysical Methods, Near Surface Geoscience 2014 – 20th European Meeting of Environmental and Engineering Geophysics.
Vafidis, A. Soupios, P., Economou, N., Hamdan, H., Andronikidis, N., Kritikakis, G., Panagopoulos, G., Manoutsoglou, E., Steiakakis, E., Candansayar, E., and Schafmeister, M., (2014), Seawater intrusion imaging at Tybaki, Crete, Greece, using geophysical data and joint inversion of electrical and seismic data, First Break, 32, 8, 107 – 114.
Vafidis, A., N. Andronikidis, H. Hamdan, G. Kritikakis, N. Economou, G. Panagopoulos, P. Soupios, E. Steiakakis & E. Manoutsoglou, (2013), The CLEARWATER project: preliminary results from the geophysical survey in Tympaki, Crete, Greece, EGE13, Chania.
Panagopoulos, G., Giannakakos, E., Manoutsoglou, E., Steiakakis, E., Soupios, E., and Vafidis, A., (2013), Definition of inferred faults using 3D geological modeling techniques: A case study in Tybaki basin in Crete, Greece, EGE13, Chania.
Emin Candansayar , İsmail Demirci, Antonis Vafidis, Pantelis Soupios, (2013), Investigation of Salt Water Intrusion with Joint Inversion of Direct Current Resistivity and Seismic Refraction Data, accepted for oral presentation to 20th International Geophysical Congress and Exhibition of Turkey, 25-27 November, Antalya, Turkey.
Pantelis Soupios, Nektarios Kourgialas, Zoi Dokou, George Karatzas, George Panagopoulos, Antonis Vafidis, Emmanuil Manoutsoglou, (2014), Modeling Saltwater Intrusion at an Agricultural Coastal Area using Geophysical Methods and the FEFLOW Model, IAEG XII Congress, 15-19 September, Torino, ITALY.
D5.2: Brochure with the results of project.
D5.3: Web page of the project.
A dedicated webpage was developed. All the relevant information available is imported in this webpage. Also, a user group tool was created in order the partners to exchange files and uoload deliverables and reports.
D5.4: Organization of one workshop and seminars on national or regional level.