1.1 本指南涵盖了对通常应用于地质、工程、地下水和环境（以下简称岩土）调查的钻孔、井、检修管、沉箱或竖井（以下简称钻孔）进行伽马、自然伽马、总计数伽马或伽马射线（以下简称伽马）测井所需的一般程序。不包括与核源一起进行伽马测量的频谱伽马和测井（例如中子活化和伽马密度测井）。不包括矿物或石油应用的伽马测井。 1.2 本指南将伽马测井定义为随深度钻孔附近地层伽马活动的记录（见 图1 和 图2 ). 图1 美国大峡谷南缘附近的伽马测井示例（在cps中） 注1: 该图演示了如何使用测井来识别特定地层，并说明了比例包络- 观察局部伽马峰，并显示如何选择两个地层之间的接触点，以与两个地层伽马活动之间过渡的中点重合。 图2 位于美国堪萨斯州海斯附近的水文观测井KGS#1 Braun的伽马测井示例（采用API单位，其中SGR反映导出的总伽马射线测井（所有辐射贡献的总和），CGR反映计算的伽马射线测井（钾和钍响应的总和，不包括铀的贡献）。 1.2.1 伽马测井通常用于描绘岩性，对比不同测井过程中进行的测量，并定义钻孔之间的地层对比（参见 图3 ). 图3 两个钻孔的伽马测井示例 注1: 研究现场显示了如何使用伽马测井来确定岩层与每个钻孔相交的位置，从而证明了地下地质的横向连续性。 1.3 本指南仅限于使用由闪烁探测器（晶体与光电倍增管耦合）组成的核计数器进行伽马测井，闪烁探测器是岩土应用中最常见的伽马测量设备。 1.4 本指南概述了伽马测井，包括一般程序、特定文件、校准和标准化以及测井质量和解释。 1.5 本指南将与指南一起使用 D5753 . 1.6 伽马测井应由受过地球物理测井程序培训的操作员收集。伽马测井应由具有测井分析经验的专业人员进行解释。 1.7 以国际单位制或英寸-磅单位（括号中给出）表示的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，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 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。 1.7.1 伽马测井通常以每秒计数（cps）或美国石油学会（API）单位记录。γ射线API单位定义为 1. / 200 校准坑内记录的放射性层中间测井仪器记录的计数率与非放射性层中间记录的计数率之间的差异。休斯顿大学目前有API装置的校准设施，是简单伽马射线工具的世界标准，但近年来校准坑的有效性受到质疑。 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、健康和环境实践，并确定监管限制的适用性。 1.9 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。本文件不能取代教育或经验，应与专业判断一起使用。并非本指南的所有方面都适用于所有情况。本ASTM标准不代表或取代必须根据其判断给定专业服务的充分性的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本文件。本文件标题中的“标准”一词仅表示该文件已通过ASTM共识程序获得批准。 1.10 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====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伽马测井至关重要。本指南将与指南一起使用 D5753 . 5.2 其使用的好处包括改进伽马测井方法和设备的选择、伽马测井质量和可靠性，以及伽马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伽马测井方法。 5.4 重要的是人员（请参阅指南的人员部分 D5753 )查阅有关伽马技术、应用和解释方法的最新教科书和报告。

1.1 This guide covers the general procedures necessary to conduct gamma, natural gamma, total count gamma, or gamma ray (hereafter referred to as gamma) 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) investigations. Spectral gamma and logging where gamma measurements are made in conjunction with a nuclear source are excluded (for example, neutron activation and gamma-gamma density logs). Gamma logging for minerals or petroleum applications are excluded. 1.2 This guide defines a gamma log as a record of gamma activity of the formation adjacent to a borehole with depth (See Fig. 1 and Fig. 2 ). FIG. 1 Example of a Gamma Log From Near the South Rim of the Grand Canyon in the USA (in cps) Note 1: This figure demonstrates how the log can be used to identify specific formations, illustrating scale wrap-around for a local gamma peak, and showing how the contact between two formations is picked to coincide with the half-way point of the transition between the gamma activities of the two formations. FIG. 2 Example of a Gamma Log for the Hydrologic Observation Well KGS #1 Braun located near Hays, Kansas in the USA (in API units whereby SGR reflects the derived total gamma ray log (the sum of all the radiation contributions), and CGR reflects the computed gamma ray log (the sum of the potassium and thorium responses, leaving out the contribution from uranium). 1.2.1 Gamma logs are commonly used to delineate lithology, correlate measurements made on different logging runs, and define stratigraphic correlation between boreholes (See Fig. 3 ). FIG. 3 Example of Gamma Logs From Two Boreholes Note 1: From a study site showing how the gamma logs can be used to identify where beds intersect each of the individual boreholes, demonstrating lateral continuity of the subsurface geology. 1.3 This guide is restricted to gamma logging with nuclear counters consisting of scintillation detectors (crystals coupled with photomultiplier tubes), which are the most common gamma measurement devices used in geotechnical applications. 1.4 This guide provides an overview of gamma logging including general procedures, specific documentation, calibration and standardization, and log quality and interpretation. 1.5 This guide is to be used in conjunction with Guide D5753 . 1.6 Gamma logs should be collected by an operator that is trained in geophysical logging procedures. Gamma logs should be interpreted by a professional experienced in log analysis. 1.7 The values stated in either SI units or inch-pound 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 used independently of the other. Combining values from the two systems may result in nonconformance with the standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard. 1.7.1 The gamma log is typically recorded in units of counts per second (cps) or American Petroleum Institute (API) units. The gamma ray API unit is defined as 1 / 200 of the difference between the count rate recorded by a logging tool in the middle of the radioactive bed and that recorded in the middle of the nonradioactive bed” recorded within the calibration pit. A calibration facility for API units currently exists at the University of Houston and is the world standard for the simple Gamma Ray tool, however the validity of the calibration pit has been called into question in recent years. 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.9 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. 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, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 An appropriately developed, documented, and executed guide is essential for the proper collection and application of gamma logs. This guide is to be used in conjunction with Guide D5753 . 5.2 The benefits of its use include improving selection of gamma logging methods and equipment, gamma log quality and reliability, and usefulness of the gamma log data for subsequent display and interpretation. 5.3 This guide applies to commonly used gamma logging methods for geotechnical applications. 5.4 It is essential that personnel (see the Personnel section of Guide D5753 ) consult up-to-date textbooks and reports on the gamma technique, application, and interpretation methods.