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This study highlights the effect of the Cretaceous greenhouse climate on weathering processes. Atmospheric CO2 level was relatively higher in the Cretaceous than it was in both the Jurassic and the Cenozoic. Consequently, temperature and humidity were higher in the Cretaceous than in the Jurassic and the Cenozoic. The interaction among the high levels of atmospheric CO2, extreme global warmth, and humidity in the Cretaceous resulted in widespread deep weathering. Cretaceous palaeo-weathering profiles are observed to occur at higher palaeolatitudes relative to the Jurassic and Cenozoic palaeo-weathering profiles. This implies the upward warming of the Cretaceous palaeolatitude, consistent with palaeotemperature estimates for the Cretaceous. The present thickness of weathering profiles in some selected tropical zones is approximately 200 m. During the greenhouse climatic condition in the Cretaceous, the thickness of weathering profiles at those areas could have been up to 4–5 times the present value. This suggests that many sediments were produced from the Cretaceous weathering events.

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Petroleum systems occur in the Neoproterozoic in several parts of the world, based on organic-rich hydrocarbon source rocks deposited during late Neoproterozoic high sea level. The Dalradian Supergroup in Argyll, Scotland, shows evidence for coupled source rock and reservoir rock. The Easdale Slate and laterally up-dip Scarba Conglomerate in the Easdale Subgroup, Argyll Group, were deposited as deep water mudrocks and submarine fan coarse pebbly sandstone respectively. The Easdale Slate contains several percent organic carbon, rich enough to be a good source rock. The pore-space in the sandstones of the Scarba Conglomerate is infilled with carbonaceous matter that originated as an oil residue. Pyrite spatially associated with the oil residue may reflect microbial sulphate reduction, as occurs in many younger petroleum reservoirs. Despite greenschist facies metamorphism, the Easdale Subgroup records a hitherto unrecognized petroleum system, which adds to a global picture of late Neoproterozoic hydrocarbon generation.

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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.