松原市扶余北断裂的发现及活动性鉴定

The discovery and identification of activities of the Fuyubei fault in Songyuan

摘要:

通过对3D及大量2D石油勘探资料的精细解释，发现并确认了位于松原市主城区北侧、距主城区仅10km处的扶余北断裂。该断裂是扶余隆起的北部边界，走向近EW，全长26km，西起孙家围子，向东延伸至大洼镇附近；断层倾向南，视倾角较陡，约60°~80°，早白垩纪为正断层，新构造运动以来表现为逆冲作用。利用浅层人工地震勘探、钻探、释光测年等多重组合方式对扶余北断裂的活动性作了鉴定，结果表明，扶余北断裂最新活动距今（23.9±0.6）ka~（28.9±0.6）ka，为晚更新世活动断裂，断裂活动造成第四系底界位错2.5m，中晚更新世地层存在明显扰动。

Abstract:

Based on 3D and a large number of 2D oil seismic exploration data,the paper discovered and identified the Fuyubei fault in Songyuan which is only 10km away in the north of the city. The Fuyubei fault is northern boundary of the Fuyu uplift with the total length 26km,in the direction of near EW. The fault starts in the west of Sunjiaweizi and extends to the east of Dawa town. The fault has an apparent sharp dip of 60°-80° and the main fault is an early Cretaceous layer and serves as a thrust since the new tectonic movement. Shallow artificial seismic,drilling,optical stimulated luminescence dating and other ways were used to study the Fuyubei fault activities. The results show that the latest active period was at(23.9±0.6)ka-(28.9±0.6)ka ago. It reveals the Fuyubei fault is a concealed active fault of late Pleistocene. The Quaternary strata dislocation by fault activities is 2.5m and there is an obvious disturbance in the middle-late strata of Pleistocene series.