Abstract:The postulate that geothermal energy might be recoverable from strata laterally equivalent to the Fell Sandstone Formation (Carboniferous: Mississippian) beneath Newcastle upon Tyne has been examined by the drilling and testing of the 1821 m deep Newcastle Science Central Deep Geothermal Borehole. This proved 376.5 m of Fell Sandstone Formation below 1400 m, much of which resembled braided river deposits found at outcrop, although some lower portions were reddened and yielded grains of aeolian affinity. Downhole logging after attainment of thermal equilibrium proved a temperature of 73°C at 1740 m, and allowed estimation of heat flow at about 88 mW m −2 . This relatively high value probably reflects deep convective transfer of heat over a distance of >8 km from the North Pennine Batholith, along the Ninety Fathom Fault. The Fell Sandstone traversed by the borehole proved to be of low hydraulic conductivity (c. 7 × 10 −5 m d −1 ). The water that entered the well was highly saline, with a Na-(Ca)-Cl signature similar to other warm waters encountered in the region. It remains for future directional drilling to establish whether sufficient natural fracture permeability can be encountered, or wells stimulated, to support commercial heat production.

Additional information:Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. In 2015 the primary energy demand in the UK was 202.5 million tonnes of oil equivalent (mtoe = 848 EJ). Of this about 58 mtoe (2.43 EJ) was used for space heating. Almost all of this heat was from burning fossil fuels either directly (50% of all gas used is for domestic purposes) or indirectly for power generation. Burning fossil fuels for heat released about 160 million tonnes of carbon dioxide in 2015. The UK must decarbonize heating for it to meet its commitments on emissions reduction.UK heat demand can be met from ultra-low-carbon, low enthalpy geothermal energy. supply. Presently only one geothermal system is exploited in the UK. It has been supplying about 1.7MWT (heat) to Southampton by extracting water at a temperature of 76°C from a depth of 1.7 km in the Wessex Basin. Like Southampton, most of the major population centers in the UK lie above or adjacent to major geothermal heat sources. The opportunity for using such heat within district heating schemes is considerable.The consequences of developing a substantial part of the UK's geothermal resource are profound. The baseload heating that could be supplied from low enthalpy geothermal energy would cause a dramatic fall in the UK's emissions of greenhouse gases, reduce the need for separate energy storage required by the intermittent renewables (wind and solar) and underpin a significant position of the nation's energy security for the foreseeable future, so lessening the UK's dependence on imported oil and gas. Investment in indigenous energy supplies would also mean retention of wealth in the UK. AbstractIn 2015 the primary energy demand in the UK was 202.5 million tonnes of oil equivalent (mtoe = 848 EJ). Of this about 58 mtoe (2.43 EJ) was used for space heating. Almost all of this heat was from burning fossil fuels either directly (50% of all gas used is for domestic purposes) or indirectly for power generation. Burning fossil fuels for heat released about 160 million tonnes of carbon dioxide in 2015. The UK must decarbonize heating for it to meet its commitments on emissions reduction. The consequences of developing a substantial part of the UK's geothermal resource are profound. The baseload heating that could be supplied from low enthalpy geothermal energy would cause a dramatic fall in the UK's emissions of greenhouse gases, reduce the need for separate energy storage required by the intermittent renewables (wind and solar) and underpin a significant position of the nation's energy se...

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The origin of the fourth member of the Eocene Shahejie Formation in the northern steep slopes of the Minfeng Sub‐sag, Dongying Sag, China, was investigated by integrating core studies and flume tank depositional simulations. A non‐channelized depositional model is proposed in this paper for nearshore subaqueous fans in steep fault‐controlled slopes of lacustrine rift basins. The deposits of nearshore subaqueous fans along the base of steep border‐fault slopes of rift basins are typically composed of deep‐water coarse‐grained sediment gravity‐flow deposits directly sourced from adjacent footwalls. Sedimentation processes of nearshore subaqueous fans respond to tectonic activities of boundary faults and to seasonal rainfall. During tectonically active stages, subaqueous debris flows triggered by episodic movements of border‐faults dominate the sedimentation. During tectonically quiescent stages, hyperpycnal flows generated by seasonal rainfall‐generated floods, normal discharges of mountain‐derived rivers and deep‐lacustrine suspension sedimentation are commonly present. The results of a series of flume tank depositional simulations show that the sediments deposited by subaqueous debris flows are wedge‐shaped and non‐channelized, whereas the sediments deposited by hyperpycnal flows generated by sporadic floods from seasonal rainfall are characterized by non‐channelized, coarse‐grained lobate depositional bodies which switch laterally because of compensation sedimentation of hyperpycanal flows. The hyperpycnal‐flow‐deposited non‐channelized lobate depositional bodies can be divided into a main body and lateral edges. The main body can be further subdivided into a proximal part, middle part and frontal part. Normal mountain‐derived river‐discharge‐deposited sediments are characterized by thin‐bedded, fine‐grained sandstones and siltstones with a limited distribution range. Normal mountain‐derived river‐discharge‐deposited sediments and deep‐lacustrine mudstones are commonly eroded in the area close to boundary faults. A nearshore subaqueous fan can be divided into three segments: inner fan, middle fan and outer fan. The inner fan is composed of debrites and the proximal part of the main body. The middle fan consists of the middle part of the main body and lateral edges, normal mountain‐derived river‐discharge‐deposited fine‐grained sediments and deep‐lacustrine mudstones. The outer fan comprises the frontal part of the main body, lateral edges, and deep‐lacustrine mudstones. Based on the non‐channelized depositional model for nearshore subaqueous fans, criteria for stratigraphic subdivision and correlation are discussed and applied.