西秦岭地区1959年以前,在地层研究方面基本属半空白区;叶连俊、关士聪(1944)和黄振辉(1959)的调查也仅限于东部天水、武都一带。根据他们的报导,西秦岭仅存在有中泥盆世晚期至晚泥盆世沉积,而缺失中泥盆世早期及早泥盆世沉积。1960年前后,兰州地层古生物中心站对迭部下吾那沟、当多沟的铁矿层进行了初步研究,采集了丰富的腕足、珊瑚化石,确定了铁矿层时代属中泥盆世早期。从1967年以来,西北地质科学研究所、甘肃地质 Before 1959, the West Qinling Mountains belonged basically to the semi-blank area in stratigraphic research. The investigations by Ye Lianjun, Guan Shicong (1944) and Huang Zhenhui (1959) were limited to the eastern Tianshui and Wudu areas. According to their reports, there are only sediments from the Late Middle Devlop to Late Devonian in the West Qinling, and the Early Devonian sediments in the Middle Devonian. Around 1960, Lanzhou Institute of Paleontology Center conducted a preliminary study on the iron deposits in Xiaoduogou and Dangdougou, and collected rich brachiopod and coral fossils. It was confirmed that the iron ore layer belonged to the early Middle Devonian. Since 1967, Northwest Institute of Geological Sciences, Gansu Geology