Geophysical indicators for gas hydrate. Data from CAGE-UiT. Data are represented as polygons.

Geological/geochemical evidences of gas hydrate. Represented as polygons. Data from Prichornomorske State Regional Geological Enterprise

Geophysical indicators for gas hydrate. Data from CSMS University of Haifa. Data are represented as polygons.

Geophysical indicators for gas hydrate. Data from UNI-Hamburg. Data are represented as polygons.

Geophysical indicators for gas hydrate. Data from CAGE-UiT, Centre for Arctic Gas Hydrate, Environment and Climate.The Arctic University of Norway . Data are represented as points.

D parameter represents the depth of the surface below the ground level where all the pore spaces are filled with water. The values of the depth to water (m) are classified into seven classes and a rate is assigned to each class (<1.5 m = [10]; 1.5 - 5 = [9]; 5 - 10 [7]; 10 - 15: [5]; 15 - 25: [3]; 25 - 50: [2]; >50 = [1]). In the Upper Guadiana Basin pilot, depth to water table is higher than 15 meters in most of the pilot area due to the intensive groundwater withdrawal since the early 1970s.

T parameter represents the slope of the land surface . The values of the slope (%) are classified into five classes and a rate is assigned to each class (0 - 2 m = [10]; 2 - 6 = [9]; 6 - 12 = [5]; 12 - 18 = [3]; >18 = [1]). In the Upper Guadiana Basin pilot, the land surface is predominantly flat, sloping gently over 150 km, from the northeast (elevation 730 m.a.s.l.) to the southwest (600 m.a.s.l.).

C parameter refers to the ability of the aquifer materials to transmit water. The values of the conductivity (m/s) are classified into eight classes and a rate is assigned to each class: < 5.0*10-7: [1] 5.0*10-7 - 5.0*10-5: [2] > 5.0*10-5 - 1.5*10-4: [3] > 1.5*10-4- 3.5*10-4: [4] > 3.5*10-4- 5.0*10-4: [6] > 5.0*10-4- 1.0*10-3: [8] > 1.0*10-3 - 1.0*10-2: [9] > 1.0*10-2: [10] In the Upper Guadiana Basin pilot, the conductivity in the Upper Guadiana Basin takes values in all the ranges proposed for the classification of this parameter in DRASTIC. The north area has low conductivity (below 1.5*10-4 m/s although there exists a small area with conductivity higher than 10-3. The central area takes values between 1.5*10-4 and 10-3 m/s and the conductivity in the southern area is mainly in the range of 3.5*10-4 – 5*10-4 m/s.

Net recharge map expressed as an index value according to DRASTIC ranges from 1 to 10, being 10 the net recharge greater than 500 mm and 1 the recharge less than 50mm.

Type of soil media map expressed as an index value according to DRASTIC ranges from 1 to 10. The lowest values in the area (index value of 4) - correspond to loam and silty loam soils and the highest values (index value of 10) correspond to gravel soils or terrains with non-existent soil.