Field-based experimental study on extraction of heat from volcanoes

从火山中提取热量的现场实验研究

基本信息

批准号：
11305073
负责人：
EHARA Sachio
金额：
$ 14.88万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11305073/
关键词：
volcano energy geothermal energy extraction of heat volcanic eruption volcano Kuju volcano monitoring underground structure

项目摘要

Kuju volcano is situated in the central part of Kyushu, southern Japan. It erupted in October 1995 and the eruption is considered to be not magmatic but phreatic or steam explosion. After the eruption, a large amount of volcanic steam discharge has been continuing. Such a process is considered to be very similar to geothermal fluid production without reinjection of liquid water. Therefore in this study, the response of Kuju volcano to the extraction of heat was estimated by monitoring of volcanic activities by using various kinds of geophysical and geochemical techniques such as estimation of heat and steam discharge rates, estimation of net mass balance by repeat gravity measurement, observation of ground deformation, seismic observation ets.Such observations show that a large amount of cold meteoric water was recharged to the central part of the volcano after the phreatic eruption and therefore the interior of the volcano was cooled down so much. But we had no change of seismic activity and also we had only a small amount of ground subsidence.Combining our observations and numerical simulation of effect of heat extraction on temperature and pressure of the underground volcanic geothermal reservoir clarified that extraction of energy equivalent to electric power generation of 10 to 100MW at Kuju volcano is feasible without remarkable effect to the natural environment in and around Kuju volcano.

九重火山位于日本南部九州中部。它于1995年10月喷发，这次喷发被认为不是岩浆喷发，而是潜水或蒸汽喷发。喷发后，大量的火山蒸汽一直持续喷出。这种过程被认为与地热流体生产非常相似，无需重新注入液态水。因此，在本研究中，通过使用各种地球物理和地球化学技术监测火山活动来估计九重火山对热量提取的响应，例如估计热量和蒸汽排放率、通过重复重力测量估计净质量平衡、地面变形观测、地震观测等。这些观测表明，火山喷发后，大量冷的大气水被补给到火山的中心部分，从而使火山内部降温。但地震活动没有变化，也只有少量的地面沉降。结合观测和数值模拟得出的排热对地下火山地热储层温度和压力的影响，明确了提取的能量相当于电力在九重火山发电10至100兆瓦是可行的，不会对九重火山及其周围的自然环境造成明显影响。