现场录井中取心层位的准确卡取

准确卡取取心层位是现场地质录井工作的重点与难点。不同目的层的取心都涉及地层的对比问题。对取心前的准备工作以及4种卡层方法(地层反射波组追踪法,岩性标准层、标志层对比法,沉积旋回对比法,测井曲线特征对比法)进行了详细介绍。归纳提出现场地质录井人员卡准取心层位需要注意的是根据与邻井的对比结果,作出该段地层的预告剖面,对即将钻开的地层做到心中有数;管理好钻具,确保井深准确;密切注意钻时、气测变化,及时捞取、描述每包岩屑,将实际剖面与预告剖面逐层对比,直至钻达预定的取心深度;当出现与地质预告不符的地层时,要及时分析原因,以便针对地层提前或推后出现而相应提前或推后取心。

Coring zone sticking accurately on wellsite mud logging

Sticking coring zone accurately is the focal and hard points for wellsite geologic logging operation, coring in different target zones involves stratum correlation problem. Therefore, the author introduced pre-drilling preparation work and 4 kinds of zone sticking methods, which were stratum reflected wave group tracing method, lithology standard horizon and reference horizon correlation method, sedimentary rock cycle correlation method, and well logging curve feature correlation method, summarized and provided the attentive items for sticking coring zone accurately on wellsite, which were working out the formation prediction profile for the interval zone according to the correlating results with the adjacent wells, knowing well with the formation that will be drilled with, making a good management on drilling tools, ensuring correct well depth, paying close attention to the changes in drilling time and gas logging, catching cuttings in time and describing each pack of cuttings, correlating the real formation profile with the prediction profile zone by zone till drilling to the predetermined coring depth. When the formation was not in accordance with the prediction profile, the reason should be analyzed in time in order to move forward or put off to coring.