准噶尔地区磁场解释及区域构造特征

根据准噶尔盆地及周围山区航空磁测结果,发现了5个沉积盖层厚度大于12km的拗陷,其中3个的盖层厚度可达18km,从而提高了盆地的油气远景评价。盆地内为隆拗相间的格局。 盆地内有一范围比盆地略小的以前寒武系为基底的稳定地块--准噶尔地块,它以断裂为边界。 盆地中部的北西西向长条状正异常,推断是由发育在下古生代裂陷槽中以基性为主的基性超基性杂岩体引起的。

INTERPRETATION OF THE MAGNETIC FIELD IN THE JUNGGAR AREA AND ITS REGIONAL STRUCTURAL FEATURES

In the area aeromagnetic maps of Junggar Basin and its peripherals, we have discovered five great depressions with the sedimentary covers more than 12 kilometres deep, and three of them, reach to 18 kilometres. The finding of these depressions greatly improve the oil-gas prospect in the basin. The structural pattern in the basin is depressions alternating with upheavals.In the basin, there is a stable block on the small side, i.e. the Junggar block that based upon the Precambrian succesion, and faults around may be taken as the boundary of it.The NWW linear high anomaly in the central part of the basin is inferred to be caused by the basic and ultrabasic complex rocks which developed in the lower Paleozoic auIacogen.