根据渭河盆地地热井、油气调查井、氦气调查井气样分析成果，结合近年来地质、物探新成果分析，发现渭河盆地各类钻井中普遍存在含氦天然气，且这些天然气，按甲烷和氦气含量可分为富氦天然气和贫氦天然气两类。位于渭河盆地边部的地热井、区域地质和物化探成果均佐证了渭河盆地基底存在上古生界，未见隐伏的花岗岩体。区域构造演化佐证了渭河盆地周边断裂的形成与区域断裂同期，盆地的形成与演化是区域演化的一部分，其主沉降期是新生代。因此，前人对渭河盆地形成的最早时间为始新世以及不存在上古生界煤系地层基底以及氦气的主要气源岩是分布于基底的富铀花岗岩体和秦岭造山带富铀花岗岩体的认识有待进一步探究。对比邻区鄂尔多斯盆地，发现渭河盆地上古生界煤系地层可作为烃源岩，伽马异常层可作为氦源层，这为重新评价渭河盆地的氦气资源地质前景提供了依据。%According to the analysis results of gas samples from the geothermal well, the investigation well of oil and helium in the Weihe Basin, we find that all kinds of drills contain gas with helium prevalently, combining the results of geology and latest geophysical prospecting in recent years. And these gas could be divided into helium-rich gases and helium-poor gases based on the content of methane and helium. The results of geology, latest geophysical prospecting and geothermal well also support that the upper Paleozoic strata exits in the Weihe Bsain and insidious granite is not discovered. The regional tectonic evolution illustrates that the faults around the Weihe Basin and regional faults formed contemporaneously, and the formation of the Weihe Basin is the part of regional evolution, which settles mainly in Cenozoic era. Therefore, the former conclusions such as the Weihe Basin begins to form in the Eocene, there is no upper Paleozoic strata with coal in the basement, and the source rock of gas is bearing-uranium granite in the basement and the Qinling orogenic belt, should be further studied and explored. Compared with Ordos Basin, we find that the upper Paleozoic strata with coal in the basement could be the source rock of gas and the Gamma anomaly strata could be the source of helium, which provides evidence to reappraise the resource prospect of helium in the Weihe Basin.
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