From the 2000s onwards, unprecedented space missions have brought about a wealth of novel investigations on the different aspects of space geomechanics. Such aspects are related to the exploratory activities such as drilling, sampling, coring, water extraction, anchoring, etc. So far, a whole range of constitutive research projects on the plate tectonics, morphology, volcanic activities and volatile content of planetary bodies have been implemented. Furthermore, various laboratory experiments on extraterrestrial samples and their artificial terrestrial simulants are continually conducted to obtain the physical and mechanical properties of the corresponding specimens. Today, with the space boom being steered by diverse space agencies, the incorporation of geomechanics into space exploration appreciably appears much needed. The primary objective of this article is to collate and integrate the up-to-date investigations related to the geomechanical applications in space technologies. Emphasis is given to the new and future applications such as planetary drilling and water extraction. The main impetus is to provide a comprehensive reference for geoscience scientists and astronauts to quickly become acquainted with the cutting-edge advancements in the area of space geomechanics. Moreover, this research study also elaborates on the operational constraints in space geomechanics which necessitate further scientific investigations.

In this research, two empirical correlations have been introduced to calculate the dynamic Biot coefficients of low-porosity and high-porosity sandstone samples from two open pit mines located in South-West Poland. The experiments were conducted using an acoustic velocity measurement apparatus. Under the undrained condition, firstly, the confining pressure was increased in increments of 200 psi, and the values of pore pressure and dynamic elastic modulus were recorded. This experiment was continued until the Skempton coefficient remained in the range of 0.98–1. Secondly, an experiment on the same sample was conducted under drained conditions, and the corresponding dynamic elastic moduli were calculated. Then, using the calculated dynamic elastic moduli, the dynamic Biot coefficient was determined for each sample under different confining pressure. Finally, two empirical correlations were formulated for each sandstone category. The results demonstrate that, as the confining pressure increases, the Biot coefficient decreases from 0.79 to 0.50 and from 0.84 to 0.45 for low-porosity and high-porosity samples, respectively. Furthermore, as the porosity increases, the sandstone behavior increasingly approaches that of soil. The empirical correlations can be used for sandstone formations with the same porosity in projects where there is not a measurement method for the Biot coefficient.

A new applicable safety factor index (SFI) was developed to identify the impact of mechanical stresses and hydrodynamic forces on the potential sanding of a sandstone reservoir. The SFI is calculated by a fully numerically coupled analysis of the mechanical deformation and hydrocarbon fluid flow in the sandstone formation via FLAC3D software, Itasca Consulting Group, Minneapolis, USA. Sand production is commonly ascribed to mechanical failure while the influence of hydrodynamic forces on sandstone erosion is neglected or underestimated. However, the new SFI enables the designer to quantify the impact of mechanical and hydrodynamic forces separately on the future occurrence of sanding. Quantitative comparison is a beneficial tool to choose the most appropriate layout of the wellbore and perforations. The results demonstrated that hydrodynamic forces may have a more significant effect on sand production than mechanical stresses. Furthermore, the sanding process does not necessarily commence at the wellbore wall and may occur at any spot around the perforations with the highest stress state. The calculated SFI was effectively utilized to reduce the sand production, an intensely problematic issue in the oil field used here as a case study. The new SFI can be deployed to design the optimum wellbore and perforation configuration to decrease the sanding potential in a sandstone formation.

A number of empirical correlations have been achieved between the hydraulic properties measured through geoelectrical methods and water well data of Arak Aquifer located in Markazi province, Iran. The geoelectrical method of Vertical Electrical Sounding (VES) technique was used to calculate the hydraulic properties of the aquifer. Through the VES technique, the pivotal hydraulic properties such as porosity, hydraulic conductivity, and specific yield of the layers were calculated. The results of VES technique were compared with the data obtained from seven observation water wells that were already drilled as exploratory coring boreholes in the region. The results demonstrate that as the porosity and hydraulic conductivity of the water-bearing layer increase, the results of VES technique appear much identical to the water well records. Furthermore, the specific yield was calculated as 4.6% that was very close to the value of 3.5% measured through the previous pumping tests. Moreover, VES technique predicted the water table of the aquifer very close to the water level monitored in the observation water wells. The obtained correlations can be used as an alternative for drilling of new observation wells that are inefficient in time and expense, and may encounter environmental limitations of drilling and site construction.

The majority of global conventional oil reservoirs have been dramatically depleted during the last few decades. To increase the oil production rate, enhanced oil recovery (EOR) techniques are commonly utilized. The ratio of the recovered oil volume to the rock volume change is defined as Biot’s coefficient. During the EOR operations, Biot’s coefficient continuously changes due to the fluid injection and oil production; however, so far, only porosity-dependent or constant values of Biot’s coefficient have been incorporated in the EOR calculations, which is not valid since the role of external stress changes is overlooked. In this research, the Biot’s coefficient of a sandstone formation was measured through the acoustic wave propagation technique. A stress-dependent equation of Biot’s coefficient was achieved for application in the EOR calculations. The findings illustrated that Biot’s coefficient decreases logarithmically with the hydrostatic stress. Moreover, the Biot’s coefficient varied from 0.52 to 0.60 for an applied hydrostatic stress of 3.50 MPa to 21 MPa. Furthermore, it was found that there was no anisotropy of Biot’s coefficient in the sandstone formations. The extracted empirical correlation can be utilized for EOR projects in which the recovered oil volume is of paramount importance economically.