Information on geothermal gradient and heat flow within the subsurface is critical in the quest for geothermal energy exploration. In a bid to ascertain the thermal potential of Nigeria sector of the Chad Basin for energy generation, subsurface temperature information from 19 oil wells, 24 water boreholes drilled to depths beyond 100 metres and atmospheric temperature from the Chad basin were utilized in calculating geothermal gradient of the area. Selected ditch cuttings from the wells were subjected to thermal conductivity test using Thermal Conductivity Scanner (TCS) at the Polish Geological Institute Laboratory in Warsaw. The terrestrial heat flow was calculated according to the Fourier's law as a simple product of the geothermal gradient and the mean thermal conductivity. Results obtained indicated geothermal gradient range of 2.81˚C/100 m to 5.88˚C/100 m with an average of 3.71˚C/100 m. The thermal conductivity values from the different representative samples range from 0.58 W/m*K to 4.207 W/m*K with an average of 1.626 W/m*K. The work presented a heat flow value ranging from 45 mW/m 2 to about 90 mW/m 2 in the Nigerian sector of the Chad Basin.

Onshore mud volcanoes are rare geological phenomena, which in Nigeria were reported for the first time few years ago in the Upper Benue Trough. In this study a detail geological mapping of the area of mud volcanoes occurrence was carried out, with the primary aim of defining their relationship, if any, to the structural geology there. The systematic field reconnaissance included field observations of the structural features, as well as analysis of the location and distribution of the onshore mud volcanoes, marking their locations on the topographic and geological maps, analysis of the aerial photographs and satellite images. The study area covered the central part of the Upper Benue Trough where the onshore mud volcanoes were found. The study area is the part of a sedimentary basin comprising Cretaceous clastic rocks that have been deformed intensively by a network of faults often embedded in the underlying Precambrian basement. This network of faults underwent a rejuvenation period from the Aptian to the Palaeocene. The most prominent tectonic structure in the study area is the NE -SW trending Kaltungo Fault Zone, however, there are other minor faults with N -S and NW -SE trends. This study shows that the mud volcanoes found in the study area are usually located near or within fault zones, within the outcropping Upper Cretaceous Yolde Formation and Upper Bima Sandstone, both of which were deformed by the Kaltungo faults, as well as by other minor faults.Worldwide, incidences of onshore mud volcano formation are usually attributed to areas of tectonic activity, rapid sedimentation or hydrocarbon occurrence. In this study, the interpretation of the field observations and mapping results, combined with information on the structural evolution of the study area and seismic pattern (very scarce), have led to the conclusion that the location of onshore mud volcanoes in the Upper Benue Trough, being located along the fault zones, is structurally controlled. The close relationship between mud volcano location and the structural framework of the area may be interpreted as one of several possible subsurface geological responses to present tectonic activity.

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The forest cover in Poland reaches almost 30% of the country’s area. Polish forests are characterized by high biodiversity. Unfortunately, in recent years, the forests of Central Europe have been affected by climate change problems, in particular meteorological drought. In Poland, even those stands which consist of species that were widely recognized as drought tolerant and easily adaptable to environmental changes are beginning to die. The article presents engineering methods applicable to forest environment protection, largely developed at the University of Life Sciences in Poznań and implemented by the State Forests—National Forest Holding in Poland, to minimize the effects of drought. Among the issues raised are ways to protect forests against fires, modern technologies for fire road surface construction and small-scale water retention in forests. A comprehensive solution to problems related to progressive drought is a must. Scientists and foresters are observing the dying of large areas of stands and, at the same time, intensification of wildlife migration due to the search for new habitats as a consequence of the drought. Therefore, the issue of building animal crossings during the current dynamic expansion of the road network in Poland has also been presented in the paper. Another subject pointed to in the text is forest tourism. Forests provide opportunities for recreation and rest to society. However, the increasing tourist pressure in some regions may cause adverse environmental effects. Finally, the paper shows some examples of supporting forest environment protection using remote sensing techniques. Generally, the aim of the paper is to present experiences and comprehensive solutions implemented in Poland.

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The geological structure of Nigeria influences geothermal exploration extent within each geological province. Sedimentary basins in Nigeria have been explored for hydrocarbons for several decades, thus the oil companies collected large subsurface temperature data basis. But not much is known about geothermal conditions within Nigerian Precambrian crystalline province.On the basis of BHT data from oil wells it has been found that geothermal gradient in Niger Delta ranges from 1.3 to 4.7°C/100m and in Anambra Basin (directly to the north) it can reach 5.5°C/100m. Exploration for geothermal energy in northern Nigeria based on shallow water wells (down to 500 m deep) was carried out over 20 years ago. Research was concentrated mainly on geothermal conditions within Sokoto and Nigerian part of Chad sedimentary basins, where relatively high geothermal gradients were found: 7.6° and 5.9°C/100m respectively. In north-western Nigeria the geothermal anomaly of Sokoto basin extends to the Niger territory.The other aspect of geothermal exploration in Nigeria is investigating of the thermal springs and seepages, which occur mainly within sediments of the Middle and Upper Benue Trough. The water of the warmest springs in that area: Akiri and Ruwan Zafi have the temperature about 54°C and it suggests the occurrence of some geothermal anomalies. So far, there is probably the only one (direct) geothermal energy utilisation site in Nigeria. It is a swimming pool where water from Ikogosi warm spring (37°C) is used. It is located in south-western part of the country, in Ekiti state.

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The manuscript presents the current state and proposals for the management of the old granite, quartz, and serpentinite quarries located in the Ślęża Massif (SW Poland, 50°51′51.22″ N; 16°42′26.80″ E), an area entirely covered by forests and protected by various legal protection measures. The quarries are abandoned and subjected to intense natural plant succession, so they are disappearing from the landscape. Nine quarries were analyzed regarding their natural and landscape characteristics. Due to the variety of their sizes, specific locations, geological–topographical traits, and forest and site conditions, the quarries may be turned into tourist attractions enhancing the social function of forests while, at the same time, ensuring their protective functions. If properly managed, they may contribute to the multifaceted development of tourism, performing scientific-cognitive, educational, sports, or cultural functions, and, as a result, to a partial reduction in the tourist pressure on biotic and abiotic natural resources along the presently most frequently used routes. This paper attempts to present arguments indicating that a former mining working site may be a positive and attractive landscape element in harmony with the vegetation cover, beneficial for both nature and humans.