| 煤层气固井声幅测井方法探讨 |
| |
| 引用本文： | 孟予萍,郭祥云.煤层气固井声幅测井方法探讨[J].中国煤炭地质,2008(12):12-13. |
| |
| 作者姓名： | 孟予萍 郭祥云 |
| |
| 作者单位： | 河南省煤炭地质勘察研究院 |
| |
| 摘 要： | 影响煤层气固井声幅测井的因素较多,如地层软硬变化大、套管内径或壁厚不均、仪器不居中、发射能量不足、接收灵敏度不够等,这些因素的存在将会导致首波丢失、时差曲线产生周波跳跃或波动现象。为提高煤层气固井声幅测井质量,要尽量保证所用仪器外径接近套管内径,以减少无效传播和能量损失,另外需提高仪器的发射能量及接收灵敏度;在自由套管和声波强吸收地层,必须保证自由套管首波不限幅、声波强吸收地层首波不丢失。在现场解释时,一般以＂自由套管＂处的偏转幅度值A为标准,将固井声幅曲线幅度的20%A和40%A作为分界点,评价固井效果。
|
| 关 键 词： | 煤层气 声幅测井 固井质量 |
A Discussion on Acoustic Amplitude Log in CBM Well Cementing |
| |
| Meng Yuping,Guo Xiangyun.A Discussion on Acoustic Amplitude Log in CBM Well Cementing[J].Coal Geology of China,2008(12):12-13. |
| |
| Authors: | Meng Yuping Guo Xiangyun |
| |
| Institution: | (Henan Provincial Coal Geological Exploration Research Institute, Zhengzhou, Henan 450052) |
| |
| Abstract: | There are quite a few factors affecting acoustic amplitude log in CBM well cementing,such as larger change of strata hardness,uneven casing inside diameter or thickness,instrument out of alignment,insufficient transmitting energy and insufficient receiving sensitiveness etc.,the existing of the factors will cause head wave loss,phenomena of periodic wave skip or fluctuation.To improve the quality of acoustic amplitude log in CBM well cementing,ensuring outside diameter of instrument is close to inside diameter of casing as far as possible,thus can reduce frustrating propagation and energy loss,enhance instrument emitted energy and receiving sensitivity.In case of free pipe and strong acoustic absorption strata,have to ensure free pipe head wave not to be sliced,no loss of head wave of strong acoustic absorption strata.During field interpretation,commonly takes deflecting amplitude A at "free pipe" as standard,20%A,40%A of well cementing acoustic curve amplitude as boundary point to evaluate well cementing effect. |
| |
| Keywords: | CBM acoustic amplitude log well cementing quality |
| 本文献已被 CNKI 维普 等数据库收录！ |
|
