CAJ | 학술논문

脆性断层一般产生于低温环境中，通常不会生成新的变质矿物，因此无法用普通的测年方法来确定断层的活动年龄。由于脆性断层中常会伴生有同期生成的石英脉，可以通过热活化电子自旋共振（ ESR）法测定石英脉的生成年龄，从而得出断层活动的年龄。如果断层带中发育了多期的石英脉，通过测定还可以得出断层多次活动的年龄。鄂尔多斯盆地西缘构造复杂，对其断裂发育机制历来存在较多争议，通过对贺兰山地区石英脉体的ESR测年分析，证实了该区由东向西逆冲的南北向断裂带形成于晚侏罗世之后，且具有多期次活动的特征。
취성단층일반산생우저온배경중，통상불회생성신적변질광물，인차무법용보통적측년방법래학정단층적활동년령。유우취성단층중상회반생유동기생성적석영맥，가이통과열활화전자자선공진（ ESR）법측정석영맥적생성년령，종이득출단층활동적년령。여과단층대중발육료다기적석영맥，통과측정환가이득출단층다차활동적년령。악이다사분지서연구조복잡，대기단렬발육궤제력래존재교다쟁의，통과대하란산지구석영맥체적ESR측년분석，증실료해구유동향서역충적남북향단렬대형성우만주라세지후，차구유다기차활동적특정。
It is very difficult to form new metamorphic minerals in the movement of brittle faults under shallow and low-temperature situation. Therefore it is impossible to determine the active ages of faults exactly through tra-ditional methods. In the activation of shallow faults, homochromous quartz veins often develop. As a result, we can use thermal activated ESR dating to obtain the ages of quartz veins, and then to determine the active ages of faults. If there are several stages of quartz veins in fault belts, the corresponding active ages of faults can also be determined. The western Ordos thrust-fold belt has a complicated structure, and its development mechanism is still controversial. A case study was made in the Helan Mountain area. According to the ESR dating of quartz veins, the SN-trending fault which thrusted from east to west in the study area was formed after the Late Jurassic, and experienced several active stages.