摘要
青海共和—贵德盆地位于秦岭—昆仑造山带＂秦昆岔口＂,是新生代断陷盆地。盆缘断裂构造、岩浆岩发育,水热活动强烈,温泉密集,超过60℃的温泉6处,最高可达93.5℃（超过当地沸点92℃为沸泉）。盆地内地温场高,据地热钻井揭露见花岗岩的3个钻孔,共和QR1孔深969m孔底温度为70℃;DR1孔深1455m孔底温度87℃;贵德R2孔深1709.56m,孔底温度可达97℃。钻孔测温,地温梯度高达6-7℃/100m,是正常地温梯度2倍,地热增温随深度而升高,推测3000m温度可达150℃-200℃。重力低推断的基底凹陷,与可控源音频大地电磁测深、地震反射波勘探推断基底界面不符,并有磁异常对应,经钻探证实,此重、磁异常为花岗岩引起。花岗岩为燕山—印支期,据区域资料对比,花岗岩铀、钍、钾丰度高、生热率高,上述进入花岗岩钻孔深部有热无水,花岗岩作为盆地热源称其为干热岩。
Gonghe-Guide Basin is a and Kunlun orogenic system, where fault Cenozoic graben basin located in the structure and magmatic rock around connection fork between Qinling the edge of basin is developed. There are 6 geothermal spring with the temperature of above 60 Celsius degree, the maximum is 93.5℃ among them. Up to now, there are 3 well which have been drilled to granite, QR1 in Gonghe is 969m with the bottom temperature of 70℃, DR1 is 1455m with the temperature of 87℃ R2 in Guide is 1709.56m with the temperature of 97℃.According to well temperature logging, the geothermal gradient is 6-7℃/100m which is 2 times high than the normal gradient. Through studying geophysical data and geological logging, the paper discussed the application of geophysical methods including telluric electromagnetic sounding of controllable source frequency, earthquake reflective wave survey.
作者
赵贵福
尉亮
李百祥
王志林
ZHAO Gui-fu WEI Liang LI Bai-xiang WANG Zhi-lin(No. 2 Geology and Mineral Exploration Team, Gansu Provincial Bureau of Geology and Mineral Exploration and Development, Lanzhou 730000, Chin)
出处
《甘肃地质》
2016年第2期62-67,共6页
Gansu Geology
