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Increasing use of the ground as a thermal reservoir is expected in the near future. Shallow geothermal energy (SGE) systems have proved to be sustainable alternative solutions for buildings and infrastructure conditioning in many areas across the globe in the past decades. Recently novel solutions, including energy geostructures, where SGE systems are coupled with foundation heat exchangers, have also been developed. The performance of these systems is dependent on a series of factors, among which the thermal properties of the soil play a major role. The purpose of this paper is to present, in an integrated manner, the main methods and procedures to assess ground thermal properties for SGE systems and to carry out a critical review of the methods. In particular, laboratory testing through either steady-state or transient methods are discussed and a new synthesis comparing results for different techniques is presented. In situ testing including all variations of the thermal response test is presented in detail, including a first comparison between new and traditional approaches. The issue of different scales between laboratory and in situ measurements is then analysed in detail. Finally, the thermo-hydro-mechanical behaviour of soil is introduced and discussed. These coupled processes are important for confirming the structural integrity of energy geostructures, but routine methods for parameter determination are still lacking.

Geoelectrical and electromagnetic (time and frequency domains) hydrogeophysical methods were applied and jointly interpreted together with auxiliary information such as regional piezometric maps, borehole lithological logs and offshore data. The objective was to retrieve the structure and geometry of the AlbufeiraRibeira de Quarteira coastal aquifer system (Algarve, Portugal) and to upgrade the current hydrogeological conceptual model. The results allowed for the detection of the freshwater-saltwater interface along the coastline and identification of the water-bearing layers and aquitards and their hydraulic relationships. An explanation for the location of the inter-and subtidal fresh groundwater discharge is also presented and a new modeling unit is proposed for groundwater flow modeling. Limitations of the used hydrogeophysical methods are indicated and recommendations are made for follow-up studies.

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The present study was carried out in the Khor-El-Ramlah area, in a Nubian sandstone aquifer. It is located in the western bank of Nasser Lake, southern Egypt, in a tectonically active area, which is dissected by many regional faults extending towards the lake. For this reason, the Nubian sandstone aquifer in this area is expected to be recharged by a large amount of seepage water from the lake. One important parameter used to quantify seepage is hydraulic conductivity. Since in this area there is no available information about hydraulic conductivity via pumping tests or laboratory examination of core samples, an attempt is made in this study to estimate hydraulic conductivity using available resistivity logs by applying the Kozeny-Carman model. The clay contamination effect on porosity estimation has been removed via application of the Waxman-Smits model. The hydraulic conductivity is estimated to be 9.5 ± 2.5 m/day for the Nubian sandstone aquifer in this area. The present result is in agreement with the estimated and measured hydraulic conductivity values for the same aquifer in nearby areas and could be used to estimate seepage in this zone. The application of geophysical well logging often provides a cost-effective and efficient alternative to estimate aquifer parameters.out. Therefore, no information about hydraulic conductivity or seepage water quantity is known for that area. In particular, the seepage quantity is expected to be higher than in other parts around the lake due to the local dense fault system.The main objective of the present study is to estimate the hydraulic conductivity of the Nubian sandstone aquifer for this area, from the measured resistivity logs of well RML, in order to make it available for any future estimation of seepage. GEOLOGICAL SETTINGThe Arabo-Nubian granitic massif is bisected by the Red Sea rift and it is the continuation of the Gulfs of Suez and Aqaba, occupying 10% of Egypt's surface. Recent tectonic structures, which represent the most active regions of the Precambrian shield outcrop in the eastern part of Egypt and Sinai.Many researchers have studied the Nubian section in the Aswan area, which lies just north of the basement trough. Shawa and Issawi (1978), Van Houten et al. (1984) and Yan et al. (2003) divided the Nubian formation into three members from bottom to top: the Tarf, Qusier and Shab members. The Tarf member overlies the Precambrian basement and is composed of yellowish and white coloured sandstone, shale and pebbly sandstone. The sandstone is well cemented and has a grain size ranging from fine to coarse. This is unconformably overlain by the Qusier member,