National foreword

This British Standard is the UK implementation of ISO 24832‑1:2026.

The UK participation in its preparation was entrusted to Technical Committee CPI/30/2, Differential pressure methods.

A list of organizations represented on this committee can be obtained on request to its committee manager.

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 October 2026.

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO document should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 193, Natural gas, Subcommittee SC 3, Upstream area.

A list of all parts in the ISO 24832 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

Shale gas, as an unconventional oil and gas resource, is an important component of the world's energy transformation process. According to the 2015 statistical data from the International Energy Information Agency, the global technically recoverable shale gas reserves have reached 214 trillion cubic meters. Compared with other conventional oil and gas resources, shale gas is stored in the shale developed with micron-sized mineral grains and nanoscale pores, presenting an overall tight structure. This poses significant challenges for measuring fundamental mineral content and characterizing the pore structure of shale reservoirs. In shale gas production practices worldwide, considering measurement resolution, operation generality and result reliability, two methods are widely used:

scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS);
focused ion beam – scanning electron microscopy (FIB-SEM) with EDS.

These two methods allow for direct observation and quantification of the mineral composition of shale at the two-dimensional scale, and nano scale pore structure in both two and three dimensions.

This document aims to improve the accuracy and consistency of analyses, standardize shale evaluation practices and promote global data comparability to facilitate international cooperation among researchers, laboratories, exploration and production companies (E&P companies) and other stakeholders in the natural gas industry.

This document facilitates precise, multi-tier quantitative assessment of shale pores, crucial for reservoir and resource evaluation, as well as optimizing drilling targets and fracturing designs. Such precision is paramount for effective exploration and development of shale gas resources.

1 Scope

This document describes the principles, equipment, materials, testing procedures, quality control and test reports for determining shale pore structure and mineral content using scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS).

This document is applicable to the analysis of pore structure by field emission SEM and mineral content of shale samples by SEM with EDS in shale gas exploration and development.

2 Normative references

3 Terms and definitions

4 Principle

5 Apparatus

5.1

5.2

5.3

5.4

5.5

5.6

5.7

5.8

5.9

6 Materials

6.1

6.2

6.3

6.4

7 Sample preparation

8 Test procedure

8.1 Determination of pore structure

8.2 Determination of mineral content

9 Quality control

9.1 Repeatability

9.2 Reproducibility

10 Test report

Bibliography