河源断裂与新丰江大桥桥址的选择

按粤赣公路设计方案，拟建的新丰江大桥将从河源断裂附近通过，桥址是选在断层上盘抑或是下盘，关系到大桥的稳定性。经考证，桥址应选在下盘硅化岩上，其理由为：(1)按规范要求，桥址在断裂附近通过时，应在同一侧，最好是下盘；(2)河源断裂虽然是一条活动断裂，但断裂面已经东移至红层与硅化岩交界处，硅化岩是中生代断裂活动标志，到新生代与砂岩花岗岩都已成为断裂下盘，已不是断裂活动标志；(3)硅化岩是坚硬而强度大的岩石。

Heyuan fault and the selection for the location of Xinfengjiang bridge

According to the Guangdong-Jiangxi highway building scheme, Xinfengjiang bridge will be constructed near Heyuan fault. It is very important to the stability of the bridge that the location is selected on the up or the down section of the fault. After investigation, we think that the bridge would be constructed on the down section which is made of quartzite. The reasons are: 1.According to the criterion, a bridge should be constructed in the same side of the fault, the down section the better, when it has to pass by a fault. 2.Though Heyuan fault is an active one, the fault plane has moved eastward to the border between the red layer and the quartzite. The quartzite is the sign of the activity of a fault in Mesozoic but not in Cenozoic. The quartzite, gristone and granite became the down section of the fault in Cenozoic. 3. The quartzite is the hard and high-strength rock.