1.1 本指南重点介绍了对通常应用于地质、工程、地下水和环境（以下简称岩土）勘探的钻孔、井、检修管、沉箱或竖井（以下简称钻孔）进行中子或中子孔隙度（以下简称中子）测井所需的一般程序。不包括使用中子水分计进行的中子土壤水分测量。不包括矿物或石油应用的中子测井以及中子活化测井，其中伽马能谱探测器用于表征暴露于中子辐射的矿物的诱发伽马活性。 1.2 本指南将中子测井定义为热中子和超热中子散射回位于中子源附近探头上的一个或多个探测器的速率记录。 1.2.1 感应测井是定量处理的，应尽可能与其他测井和数据一起解释。 1.2.2 中子测井通常用于:( 1. )描绘岩性，以及( 2. )指示地层的充水孔隙度（参见 图1 ). N c = 校正中子测井， N 0 = 原始中子测井， C 上海 = 基于10和120 cps端点之间的伽马测井位置计算的页岩分数，以及 Φ 上海 = 页岩非有效孔隙度估计约为40 % 从日志上的间隔中选取，其中Φ 上海 = 1.0. 1.3 本指南仅限于使用由闪烁探测器（与光电倍增管耦合的晶体）组成的核计数器进行中子测井，或 3. -带或不带Cd箔盖或涂层的管探测器，以排除热中子。 1.4 本指南概述了中子测井，包括:( 1. )一般程序；( 2. )具体文件；( 3. )校准和标准化，以及( 4. )测井质量和解释。 1.5 有关中子测井的更多信息，请参阅本指南中的参考资料部分。 1.6 本指南提供了有组织的信息收集或一系列选项，并不推荐具体的行动方案。本指南不应作为中子测井的唯一标准，也不应取代教育、经验和专业判断。中子测井程序应进行调整，以满足一系列应用的需要，并在一般情况下加以说明，以便不抑制灵活性或创新性。并非本指南的所有方面都适用于所有情况。 本ASTM标准不代表或取代在不考虑项目的许多独特方面的情况下判断给定专业服务是否充分的谨慎标准。本文件标题中的“标准”一词表示该文件已通过ASTM共识程序获得批准。 1.7 单位- 括号中以英寸-磅单位或国际单位表示的数值应单独视为标准值。每个系统中规定的值可能不是精确的等效值；因此，每个系统应独立使用。将两个系统的值合并可能会导致不符合标准。如适用，添加:“以国际单位制以外的单位报告试验结果不应视为不符合本标准。 ” 1.8 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管要求的适用性。中子测井中放射源的使用带来了与中子源的运输和处理相关的重大安全问题，以及确保中子源在测井过程中不会丢失或损坏的程序。不同国家对使用放射源进行测井有不同的限制，核管理机构（NRC）对授权进行核源测井的人员的许可证持有严格的规则和条例。 ====意义和用途====== 5.1 适当制定、记录和执行的指南对于正确收集和应用中子测井至关重要。 5.2 其使用的好处包括改进中子测井方法和设备的选择；中子测井质量和可靠性；中子测井数据对后续显示和解释的有用性。 5.3 本指南适用于岩土工程应用中常用的中子测井方法。

1.1 This guide is focused on the general procedures necessary to conduct neutron or neutron porosity (hereafter referred to as neutron) logging of boreholes, wells, access tubes, caissons, or shafts (hereafter referred to as boreholes) as commonly applied to geologic, engineering, groundwater and environmental (hereafter referred to as geotechnical) explorations. Neutron soil moisture measurements made using neutron moisture gauges, are excluded. Neutron logging for minerals or petroleum applications is excluded, along with neutron activation logs where gamma spectral detectors are used to characterize the induced gamma activity of minerals exposed to neutron radiation. 1.2 This guide defines a neutron log as a record of the rate at which thermal and epithermal neutrons are scattered back to one or more detectors located on a probe adjacent to a neutron source. 1.2.1 Induction logs are treated quantitatively and should be interpreted with other logs and data whenever possible. 1.2.2 Neutron logs are commonly used to: ( 1 ) delineate lithology, and ( 2 ) indicate the water-filled porosity of formations (see Fig. 1 ). N c = corrected neutron log, N 0 = original neutron log, C sh = computed shale fraction based upon the gamma log position between the endpoints of 10 and 120 cps, and Φ sh = estimate of shale non-effective porosity of about 40 % picked from intervals on the log where Φ sh = 1.0. 1.3 This guide is restricted to neutron logging with nuclear counters consisting of scintillation detectors (crystals coupled with photomultiplier tubes), or to He 3 -tube detectors with or without Cd foil covers or coatings to exclude thermalized neutrons. 1.4 This guide provides an overview of neutron logging including: ( 1 ) general procedures; ( 2 ) specific documentation; ( 3 ) calibration and standardization, and ( 4 ) log quality and interpretation. 1.5 To obtain additional information on neutron logs see References section in this guide. 1.6 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This guide should not be used as a sole criterion for neutron logging and does not replace education, experience, and professional judgment. Neutron logging procedures should be adapted to meet the needs of a range of applications and stated in general terms so that flexibility or innovation are not suppressed. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged without consideration of a project's many unique aspects. The word standard in the title of this document means that the document has been approved through the ASTM consensus process. 1.7 Units— The values stated in either inch-pound units or SI units given in brackets are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be use independently of the other. Combining values from the two systems may result in non-conformance with the standard. Add if appropriate: “Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.” 1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use. The use of radioactive sources in neutron logging introduces significant safety issues related to the transportation and handling of neutron sources, and in procedures to ensure that sources are not lost or damaged during logging. There are different restrictions on the use of radioactive sources in logging in different states, and the Nuclear Regulatory Agency (NRC) maintains strict rules and regulations for the licensing of personnel authorized to conduct nuclear source logging. ====== Significance And Use ====== 5.1 An appropriately developed, documented, and executed guide is essential for the proper collection and application of neutron logs. 5.2 The benefits of its use include improving selection of neutron logging methods and equipment; neutron log quality and reliability; usefulness of the neutron log data for subsequent display and interpretation. 5.3 This guide applies to commonly used neutron logging methods for geotechnical applications.