先成 meaning in Chinese
antecedence
preformation
Examples
- Antecedent sedimentary basin
先成沉积盆地 - Planation surface is a wide - ranging and undulating surface formed by planation in a long and relative stable period or in a decreacing - development period . it is near the base level and there always exists some deposits such as crust of weathering above it . planation surface is often uplifted or buried by the later tectonic activities
夷平面是在长期的地壳相对稳定时期或地壳下降发展阶段，由广泛的夷平作用以截断面形式横切所有先成的地层和构造的接近侵蚀基准面的平缓的地表形态，其上常有风化壳等碎屑堆积，常遭到后期的抬升切割或埋藏，分布于地球的各纬度带。 - At first , i analyses the geological characters , and studies the procedure of the construction of deep water pile foundation of the highway bridges . then i put forward two programs of the construction in this condition : one is the construction of the steel round the barrage before the bore peg ' s , the other is on the contrary , and compare the shortcomings and the advantages of those
本文通过对岩溶地区公路桥梁深水桩基础施工的地质特征分析，研究了深水桩基施工程序，提出了在岩溶地质条件下先下钢围堰后施工钻孔桩和先成桩后施工钢围堰的两种施工方案，并对两方案的优缺点进行了分析比较。 - And the generalized homothetic composite action of metallogenic subsystems mentioned above formed the multiple - composite metallogenic system of the jiangda tectonic belt . the typical ore deposits of jiangda tectonic belt , such as dingqinnong , jiaduoling , renda etc , are contact metasomatic type deposits formed intracontinental rifting stage , and the tectonic - magmatic - hydrotherm of intracontinental orogenic stage superposed and rebuilt some preexistent ore body . their space distribution is controlled by composite intrusive rock belt of ne direction
对丁钦弄、加多岭、仁达等典型矿床的研究表明，它们均为形成于陆内裂谷作用阶段的接触交代型矿床，陆内造山期的构造?岩浆?热液作用叠加改造了先成矿体，矿床空间分布受北东向复合侵入岩带控制。