SIST EN ISO 19901-10:2022

Petroleum and natural gas industries - Specific requirements for offshore structures - Part 10: Marine geophysical investigations (ISO 19901-10:2021)

This document provides requirements and guidelines for marine geophysical investigations. It is applicable to operators/end users, contractors and public and regulatory authorities concerned with marine site investigations for offshore structures for petroleum and natural gas industries.
This document provides requirements, specifications, and guidance for:
a)   objectives, planning, and quality management;
b)   positioning;
c)   seafloor mapping, including instrumentation and acquisition parameters, acquisition methods, and deliverables;
d)   sub-seafloor mapping, including seismic instrumentation and acquisition parameters, and non-seismic-reflection methods;
e)   reporting;
f)   data integration, interpretation, and investigation of geohazards.
This document is applicable to investigation of the seafloor and the sub-seafloor, from shallow coastal waters to water depths of 3 000 m and more. It provides guidance for the integration of the results from marine soil investigations and marine geophysical investigations with other relevant datasets.
NOTE 1   The depth of interest for sub-seafloor mapping depends on the objectives of the investigation. For offshore construction, the depths of investigation are typically in the range 1 m below seafloor to 200 m below seafloor. Some methods for sub-seafloor mapping can also achieve much greater investigation depths, for example for assessing geohazards for hydrocarbon well drilling.
There is a fundamental difference between seafloor mapping and sub-seafloor mapping: seafloor signal resolution can be specified, while sub-seafloor signal resolution and penetration cannot. This document therefore contains requirements for the use of certain techniques for certain types of seafloor mapping and sub-seafloor mapping (similarly, requirements are given for certain aspects of data processing). If other techniques can be shown to obtain the same information, with the same or better resolution and accuracy, then those techniques may be used. Mapping of pre-drilling well-site geohazards beneath the seafloor is part of the scope of this document.
NOTE 2   This implies depths of investigation that are typically 200 m below the first pressure-containment casing string or 1 000 m below the seafloor, whichever is greatest. Mapping of pre-drilling well-site geohazards is therefore the deepest type of investigation covered by this document.
In this document, positioning information relates only to the positioning of survey platforms, sources and receivers. The processes used to determine positions of seafloor and sub-seafloor data points are not covered in this document.
Guidance only is given in this document for the use of marine shear waves, marine surface waves, electrical resistivity imaging and electromagnetic imaging.

Erdöl- und Erdgasindustrie - Spezielle Anforderungen für Offshore-Anlagen - Teil 10: Meeresgeophysikalische Untersuchungen (ISO 19901-10:2021)

Industries du pétrole et du gaz naturel - Exigences spécifiques relatives aux structures en mer - Partie 10: Enquêtes géophysiques marines (ISO 19901-10:2021)

Industrija nafte in zemeljskega plina - Posebne zahteve za konstrukcije na morju - 10. del: Morske geofizikalne preiskave (ISO 19901-10:2021)

Ta dokument določa zahteve in smernice za morske geofizikalne preiskave. Uporablja se za upravljavce/končne uporabnike, pogodbenike ter javne in regulativne organe, ki izvajajo morske geofizikalne preiskave za konstrukcije na morju v industriji za predelavo nafte in zemeljskega plina.
Ta dokument določa zahteve, specifikacije in smernice za:
a)   cilje, načrtovanje in vodenje kakovosti;
b)   določanje položaja;
c)   kartiranje morskega dna, vključno s parametri za instrumentacijo in pridobivanje, metodami za pridobivanje in rezultati;
d)   kartiranje območja pod morskim dnom, vključno s parametri za seizmično instrumentacijo in pridobivanje ter metodami za neseizmično refleksijo;
e)   poročanje;
f)   vključevanje in razlago podatkov ter preiskave geoloških nevarnosti.
Ta dokument se uporablja za preiskave morskega dna in območja pod morskim dnom, od obalnih plitvin do globin voda 3000 m in več. Zagotavlja smernice za vključitev rezultatov iz preiskav morskega dna in morskih geofizikalnih preiskav z drugimi ustreznimi nabori podatkov.
OPOMBA 1:   Globina, pri kateri se izvaja kartiranje območja pod morskim dnom, je odvisna od ciljev preiskave. Pri konstrukcijah na morju se preiskave običajno izvajajo na globini od 1 do 200 m pod morskim dnom. Z nekaterimi metodami za kartiranje območja pod morskim dnom je mogoče preiskave izvajati tudi veliko globlje (npr. za ocenjevanje geoloških nevarnosti pri izvrtinah ogljikovodikov).
Kartiranje morskega dna in kartiranje območja pod morskim dnom se bistveno razlikujeta: ločljivost signalov na morskem dnu je mogoče določiti, medtem ko to ne velja za ločljivost signalov v območju pod morskim dnom in njihov prodor. Ta dokument zato vsebuje zahteve za uporabo določenih tehnik za določene vrste kartiranja morskega dna in kartiranja območja pod morskim dnom (podobno so podane tudi zahteve za določene vidike obdelave podatkov). Če je mogoče za druge tehnike dokazati, da podajajo enake informacije – z enako ali boljšo ločljivostjo in točnostjo – se lahko uporabljajo te tehnike. Kartiranje geoloških nevarnosti pod morskim dnom na območjih izvrtin pred vrtanjem je del področja uporabe tega dokumenta.
OPOMBA 2:   To pomeni izvajanje preiskav na globinah, ki so običajno 200 m pod prvim cevnim stebrom za zadrževanje tlaka ali 1000 m pod morskim dnom (odvisno od tega, kaj je globlje). Zato je kartiranje geoloških nevarnosti pod morskim dnom na območjih izvrtin pred vrtanjem najgloblja vrsta preiskav, zajetih v tem dokumentu.
V tem dokumentu se informacije o določanju položaja navezujejo le na določitev položaja raziskovalnih ploščadi, virov in sprejemnikov. Postopki za določanje položajev podatkovnih točk na morskem dnu in v območju pod morskim dnom v tem dokumentu niso zajeti.
V tem dokumentu so podane zgolj smernice za uporabo morskih strižnih valov, morskih površinskih valov, meritev električne upornosti in elektromagnetnega slikanja.

General Information

• Status: Published
• Public Enquiry End Date: 31-Dec-2021
• Publication Date: 21-Feb-2022
• ICS: 75.180.10 - Exploratory, drilling and extraction equipment
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 16-Feb-2022
• Due Date: 23-Apr-2022
• Completion Date: 22-Feb-2022
• Ref Project: EN ISO 19901-10:2022 - Petroleum and natural gas industries - Specific requirements for offshore structures - Part 10: Marine geophysical investigations (ISO 19901-10:2021)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 19901-10:2022
01-april-2022
Industrija nafte in zemeljskega plina - Posebne zahteve za konstrukcije na morju -
10. del: Morske geofizikalne preiskave (ISO 19901-10:2021)
Petroleum and natural gas industries - Specific requirements for offshore structures -
Part 10: Marine geophysical investigations (ISO 19901-10:2021)
Erdöl- und Erdgasindustrie - Spezielle Anforderungen für Offshore-Anlagen - Teil 10:
Meeresgeophysikalische Untersuchungen (ISO 19901-10:2021)
Industries du pétrole et du gaz naturel - Exigences spécifiques relatives aux structures
en mer - Partie 10: Enquêtes géophysiques marines (ISO 19901-10:2021)
Ta slovenski standard je istoveten z: EN ISO 19901-10:2022
ICS:
75.180.10 Oprema za raziskovanje, Exploratory, drilling and
vrtanje in odkopavanje extraction equipment
SIST EN ISO 19901-10:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 19901-10:2022

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SIST EN ISO 19901-10:2022


EN ISO 19901-10
EUROPEAN STANDARD

NORME EUROPÉENNE

February 2022
EUROPÄISCHE NORM
ICS 75.180.10
English Version

Petroleum and natural gas industries - Specific
requirements for offshore structures - Part 10: Marine
geophysical investigations (ISO 19901-10:2021)
Industries du pétrole et du gaz naturel - Exigences Erdöl- und Erdgasindustrie - Spezielle Anforderungen
spécifiques relatives aux structures en mer - Partie 10: für Offshore-Anlagen - Teil 10: Meeresgeophysikalische
Enquêtes géophysiques marines (ISO 19901-10:2021) Untersuchungen (ISO 19901-10:2021)
This European Standard was approved by CEN on 7 February 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19901-10:2022 E
worldwide for CEN national Members.

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SIST EN ISO 19901-10:2022
EN ISO 19901-10:2022 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 19901-10:2022
EN ISO 19901-10:2022 (E)
European foreword
The text of ISO 19901-10:2021 has been prepared by Technical Committee ISO/TC 67 "Materials,
equipment and offshore structures for petroleum, petrochemical and natural gas industries” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 19901-10:2022
by Technical Committee CEN/TC 12 “Materials, equipment and offshore structures for petroleum,
petrochemical and natural gas industries” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2022, and conflicting national standards shall
be withdrawn at the latest by August 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 19901-10:2021 has been approved by CEN as EN ISO 19901-10:2022 without any
modification.

3

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SIST EN ISO 19901-10:2022

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SIST EN ISO 19901-10:2022
INTERNATIONAL ISO
STANDARD 19901-10
First edition
2021-03
Petroleum and natural gas
industries — Specific requirements
for offshore structures —
Part 10:
Marine geophysical investigations
Industries du pétrole et du gaz naturel — Exigences spécifiques
relatives aux structures en mer —
Partie 10: Enquêtes géophysiques marines
Reference number
ISO 19901-10:2021(E)
©
ISO 2021

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SIST EN ISO 19901-10:2022
ISO 19901-10:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

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SIST EN ISO 19901-10:2022
ISO 19901-10:2021(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3  Terms and definitions . 2
4 Symbols and abbreviated terms .12
4.1 Symbols .12
4.2 Abbreviated terms .13
5  Objectives, planning, and quality management .14
5.1 General .14
5.1.1 Objectives and project specifications .14
5.1.2 Georeferencing and GIS .15
5.1.3 Ground model .15
5.2 Desk study .16
5.2.1 General.16
5.2.2 Use of exploration 2D and 3D seismic data in a desk study .17
5.2.3 Desk study for pre-drilling well-site investigations .17
5.3 Scoping and planning .17
5.3.1 General.17
5.3.2 Scoping of seafloor mapping and sub-seafloor mapping .19
5.4 Operations planning and data quality management .22
5.4.1 Quality plan .22
5.4.2 Effects of attenuation .23
5.4.3 Data quality management .23
6 Positioning .23
6.1 General .23
6.2 Coordinate reference systems .24
6.2.1 Horizontal coordinate reference system .24
6.2.2 Vertical coordinate reference system.24
6.3 Surface positioning requirements .25
6.4 Vessel heading .25
6.4.1 General.25
6.4.2 Gyro compass .25
6.4.3 GNSS based heading reference .26
6.4.4 Alignment .26
6.5 Sub-sea positioning — Ultra-short baseline system .26
6.6 Inertial navigation system .27
6.7 Auxiliary sensor: doppler velocity log .27
6.8 Auxiliary sensor: altimeter .27
6.9 Auxiliary sensor: pressure-depth sensor .28
7  Seafloor mapping .28
7.1 General .28
7.2 Instrumentation and acquisition parameters .29
7.2.1 Multi-beam echo sounder .29
7.2.2 Side scan sonar .31
7.2.3 Auxiliary sensor: velocity of sound in seawater .31
7.3 Data acquisition methods .32
7.3.1 General.32
7.3.2 Reconnaissance seafloor mapping .32
7.3.3 Engineering seafloor mapping .33
7.3.4 Detailed engineering seafloor mapping .33
7.4 Seafloor mapping deliverables .33
© ISO 2021 – All rights reserved iii

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SIST EN ISO 19901-10:2022
ISO 19901-10:2021(E)

8  Sub-seafloor mapping .34
8.1 General .34
8.1.1 Resolution and signal penetration .34
8.1.2 Equipment selection for sub-seafloor mapping methods .35
8.1.3 Assessment of data quality .35
8.1.4 Deliverables .36
8.2 Acquisition equipment and parameters for seismic data .36
8.2.1 Equipment performance .36
8.2.2 Acquisition and processing parameters .37
8.2.3 High resolution seismic reflection .40
8.2.4 Ultra-high-resolution seismic reflection .44
8.2.5 Ultra-ultra-high resolution seismic reflection .44
8.2.6 Sub-bottom profiling .45
8.3 Non-seismic reflection methods .46
8.3.1 Seismic refraction .46
8.3.2 Magnetometer and magnetic gradiometer.47
8.3.3 Marine shear waves .47
8.3.4 Marine surface waves .48
8.3.5 Electrical resistivity imaging .48
8.3.6 Electromagnetic imaging .48
9  Reporting of seafloor mapping and sub-seafloor mapping .48
9.1 General .48
9.2 Record of data acquisition operations .48
9.3 Record of data processing .49
9.4 Results report .49
10 Data integration, interpretation and investigation of geohazards.50
10.1 General .50
10.2 Horizons, isopachs and isochores .50
10.3 Mapping stratigraphic units and defining geochronology .50
10.4 Time-to-depth conversion .51
10.5 Borehole geophysical logging .51
10.6 Investigation of geohazards .52
10.7 Integrated studies . .52
Annex A (informative) Additional information and guidance .53
Bibliography .78
iv © ISO 2021 – All rights reserved

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SIST EN ISO 19901-10:2022
ISO 19901-10:2021(E)

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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 7, Offshore
structures.
A list of all parts in the ISO 19901 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.
© ISO 2021 – All rights reserved v

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SIST EN ISO 19901-10:2022
ISO 19901-10:2021(E)

Introduction
The general objective of a marine site investigation is to provide information about the seafloor, the
sub-seafloor and geological processes affecting both, geohazards, and human-made objects at or
below the seafloor. Marine site investigations can encompass both marine soil investigations and
marine geophysical investigations, as shown in Figure 1. This document provides requirements for
marine geophysical investigations to support oil and gas developments offshore, is complementary to
ISO 19901-8 on marine soil investigations, and provides guidance on the integration of both types of
investigations.
Figure 1 — Marine geophysical investigations as part of marine site investigations.
NOTE Subjects denoted in grey boxes in Figure 1 are neither covered in ISO 19901-8 nor in this document.
However, marine geophysical investigations can provide information about soils and rocks, whereas rocks are
only covered by ISO 19910-8 to the extent that ordinary marine soil investigation tools can be used, e.g. for chalk.
Marine site investigations for a specific project can comprise both geophysical and geotechnical
investigations, depending on project scale and complexity. It is common practice to conduct first a
marine geophysical investigation, sometimes in combination with a limited marine soil investigation
consisting of shallow soil sampling and/or in situ testing. A more extensive marine soil investigation
is often conducted at a later stage. In some cases, a marine site investigation can consist solely of a
stand-alone geophysical survey that has a specific and limited purpose. A marine site investigation
can also consist solely of a stand-alone marine soil investigation, for which details on soil investigation
equipment and procedures are provided in ISO 19901-8.
Particular objectives of a marine geophysical investigation should be addressed in project specifications,
which should specify desired investigation depths, desired resolutions (horizontal and vertical), and
whether the objective is to illuminate the seafloor and/or the sub-seafloor. Caution is necessary in
the selection of the type of equipment to be used, and operational parameters for that equipment, in
order to meet those desired depths, resolutions, and illumination targets, particularly because local
site conditions can affect the abilities of certain equipment to meet those objectives. This document
includes discussion of the selection and operation of appropriate geophysical equipment.
Marine geophysical investigations and marine soil investigations can be (and often are) carried out as
separate exercises, the results of which can be integrated into a ground model. This document applies
to critical stages in the development of a ground model, from the initial conception stage through
successive stages of increased detail.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “can” indicates a possibility or a capability;
— “may” indicates a permission.
Annex A provides additional information intended to assist the understanding or use of this document.
vi © ISO 2021 – All rights reserved

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SIST EN ISO 19901-10:2022
INTERNATIONAL STANDARD ISO 19901-10:2021(E)
Petroleum and natural gas industries — Specific
requirements for offshore structures —
Part 10:
Marine geophysical investigations
1 Scope
This document provides requirements and guidelines for marine geophysical investigations. It is
applicable to operators/end users, contractors and public and regulatory authorities concerned with
marine site investigations for offshore structures for petroleum and natural gas industries.
This document provides requirements, specifications, and guidance for:
a) objectives, planning, and quality management;
b) positioning;
c) seafloor mapping, including instrumentation and acquisition parameters, acquisition methods, and
deliverables;
d) sub-seafloor mapping, including seismic instrumentation and acquisition parameters, and non-
seismic-reflection methods;
e) reporting;
f) data integration, interpretation, and investigation of geohazards.
This document is applicable to investigation of the seafloor and the sub-seafloor, from shallow coastal
waters to water depths of 3 000 m and more. It provides guidance for the integration of the results from
marine soil investigations and marine geophysical investigations with other relevant datasets.
NOTE 1 The depth of interest for sub-seafloor mapping depends on the objectives of the investigation. For
offshore construction, the depths of investigation are typically in the range 1 m below seafloor to 200 m below
seafloor. Some methods for sub-seafloor mapping can also achieve much greater investigation depths, for
example f
...

SLOVENSKI STANDARD
oSIST prEN ISO 19901-10:2021
01-december-2021
Industrija nafte in zemeljskega plina - Posebne zahteve za konstrukcije na morju -
10. del: Morske geofizikalne preiskave (ISO 19901-10:2021)
Petroleum and natural gas industries - Specific requirements for offshore structures -
Part 10: Marine geophysical investigations (ISO 19901-10:2021)
Erdöl- und Erdgasindustrie - Spezielle Anforderungen für Offshore-Anlagen - Teil 10:
Meeresgeophysikalische Untersuchungen (ISO 19901-10:2021)
Industries du pétrole et du gaz naturel - Exigences spécifiques relatives aux structures
en mer - Partie 10: Enquêtes géophysiques marines (ISO 19901-10:2021)
Ta slovenski standard je istoveten z: prEN ISO 19901-10
ICS:
75.180.10 Oprema za raziskovanje, Exploratory, drilling and
vrtanje in odkopavanje extraction equipment
oSIST prEN ISO 19901-10:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 19901-10:2021

---------------------- Page: 2 ----------------------
oSIST prEN ISO 19901-10:2021
INTERNATIONAL ISO
STANDARD 19901-10
First edition
2021-03
Petroleum and natural gas
industries — Specific requirements
for offshore structures —
Part 10:
Marine geophysical investigations
Industries du pétrole et du gaz naturel — Exigences spécifiques
relatives aux structures en mer —
Partie 10: Enquêtes géophysiques marines
Reference number
ISO 19901-10:2021(E)
©
ISO 2021

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oSIST prEN ISO 19901-10:2021
ISO 19901-10:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

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oSIST prEN ISO 19901-10:2021
ISO 19901-10:2021(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3  Terms and definitions . 2
4 Symbols and abbreviated terms .12
4.1 Symbols .12
4.2 Abbreviated terms .13
5  Objectives, planning, and quality management .14
5.1 General .14
5.1.1 Objectives and project specifications .14
5.1.2 Georeferencing and GIS .15
5.1.3 Ground model .15
5.2 Desk study .16
5.2.1 General.16
5.2.2 Use of exploration 2D and 3D seismic data in a desk study .17
5.2.3 Desk study for pre-drilling well-site investigations .17
5.3 Scoping and planning .17
5.3.1 General.17
5.3.2 Scoping of seafloor mapping and sub-seafloor mapping .19
5.4 Operations planning and data quality management .22
5.4.1 Quality plan .22
5.4.2 Effects of attenuation .23
5.4.3 Data quality management .23
6 Positioning .23
6.1 General .23
6.2 Coordinate reference systems .24
6.2.1 Horizontal coordinate reference system .24
6.2.2 Vertical coordinate reference system.24
6.3 Surface positioning requirements .25
6.4 Vessel heading .25
6.4.1 General.25
6.4.2 Gyro compass .25
6.4.3 GNSS based heading reference .26
6.4.4 Alignment .26
6.5 Sub-sea positioning — Ultra-short baseline system .26
6.6 Inertial navigation system .27
6.7 Auxiliary sensor: doppler velocity log .27
6.8 Auxiliary sensor: altimeter .27
6.9 Auxiliary sensor: pressure-depth sensor .28
7  Seafloor mapping .28
7.1 General .28
7.2 Instrumentation and acquisition parameters .29
7.2.1 Multi-beam echo sounder .29
7.2.2 Side scan sonar .31
7.2.3 Auxiliary sensor: velocity of sound in seawater .31
7.3 Data acquisition methods .32
7.3.1 General.32
7.3.2 Reconnaissance seafloor mapping .32
7.3.3 Engineering seafloor mapping .33
7.3.4 Detailed engineering seafloor mapping .33
7.4 Seafloor mapping deliverables .33
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8  Sub-seafloor mapping .34
8.1 General .34
8.1.1 Resolution and signal penetration .34
8.1.2 Equipment selection for sub-seafloor mapping methods .35
8.1.3 Assessment of data quality .35
8.1.4 Deliverables .36
8.2 Acquisition equipment and parameters for seismic data .36
8.2.1 Equipment performance .36
8.2.2 Acquisition and processing parameters .37
8.2.3 High resolution seismic reflection .40
8.2.4 Ultra-high-resolution seismic reflection .44
8.2.5 Ultra-ultra-high resolution seismic reflection .44
8.2.6 Sub-bottom profiling .45
8.3 Non-seismic reflection methods .46
8.3.1 Seismic refraction .46
8.3.2 Magnetometer and magnetic gradiometer.47
8.3.3 Marine shear waves .47
8.3.4 Marine surface waves .48
8.3.5 Electrical resistivity imaging .48
8.3.6 Electromagnetic imaging .48
9  Reporting of seafloor mapping and sub-seafloor mapping .48
9.1 General .48
9.2 Record of data acquisition operations .48
9.3 Record of data processing .49
9.4 Results report .49
10 Data integration, interpretation and investigation of geohazards.50
10.1 General .50
10.2 Horizons, isopachs and isochores .50
10.3 Mapping stratigraphic units and defining geochronology .50
10.4 Time-to-depth conversion .51
10.5 Borehole geophysical logging .51
10.6 Investigation of geohazards .52
10.7 Integrated studies . .52
Annex A (informative) Additional information and guidance .53
Bibliography .78
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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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 7, Offshore
structures.
A list of all parts in the ISO 19901 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.
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Introduction
The general objective of a marine site investigation is to provide information about the seafloor, the
sub-seafloor and geological processes affecting both, geohazards, and human-made objects at or
below the seafloor. Marine site investigations can encompass both marine soil investigations and
marine geophysical investigations, as shown in Figure 1. This document provides requirements for
marine geophysical investigations to support oil and gas developments offshore, is complementary to
ISO 19901-8 on marine soil investigations, and provides guidance on the integration of both types of
investigations.
Figure 1 — Marine geophysical investigations as part of marine site investigations.
NOTE Subjects denoted in grey boxes in Figure 1 are neither covered in ISO 19901-8 nor in this document.
However, marine geophysical investigations can provide information about soils and rocks, whereas rocks are
only covered by ISO 19910-8 to the extent that ordinary marine soil investigation tools can be used, e.g. for chalk.
Marine site investigations for a specific project can comprise both geophysical and geotechnical
investigations, depending on project scale and complexity. It is common practice to conduct first a
marine geophysical investigation, sometimes in combination with a limited marine soil investigation
consisting of shallow soil sampling and/or in situ testing. A more extensive marine soil investigation
is often conducted at a later stage. In some cases, a marine site investigation can consist solely of a
stand-alone geophysical survey that has a specific and limited purpose. A marine site investigation
can also consist solely of a stand-alone marine soil investigation, for which details on soil investigation
equipment and procedures are provided in ISO 19901-8.
Particular objectives of a marine geophysical investigation should be addressed in project specifications,
which should specify desired investigation depths, desired resolutions (horizontal and vertical), and
whether the objective is to illuminate the seafloor and/or the sub-seafloor. Caution is necessary in
the selection of the type of equipment to be used, and operational parameters for that equipment, in
order to meet those desired depths, resolutions, and illumination targets, particularly because local
site conditions can affect the abilities of certain equipment to meet those objectives. This document
includes discussion of the selection and operation of appropriate geophysical equipment.
Marine geophysical investigations and marine soil investigations can be (and often are) carried out as
separate exercises, the results of which can be integrated into a ground model. This document applies
to critical stages in the development of a ground model, from the initial conception stage through
successive stages of increased detail.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “can” indicates a possibility or a capability;
— “may” indicates a permission.
Annex A provides additional information intended to assist the understanding or use of this document.
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oSIST prEN ISO 19901-10:2021
INTERNATIONAL STANDARD ISO 19901-10:2021(E)
Petroleum and natural gas industries — Specific
requirements for offshore structures —
Part 10:
Marine geophysical investigations
1 Scope
This document provides requirements and guidelines for marine geophysical investigations. It is
applicable to operators/end users, contractors and public and regulatory authorities concerned with
marine site investigations for offshore structures for petroleum and natural gas industries.
This document provides requirements, specifications, and guidance for:
a) objectives, planning, and quality management;
b) positioning;
c) seafloor mapping, including instrumentation and acquisition parameters, acquisition methods, and
deliverables;
d) sub-seafloor mapping, including seismic instrumentation and acquisition parameters, and non-
seismic-reflection methods;
e) reporting;
f) data integration, interpretation, and investigation of geohazards.
This document is applicable to investigation of the seafloor and the sub-seafloor, from shallow coastal
waters to water depths of 3 000 m and more. It provides guidance for the integration of the results from
marine soil investigations and marine geophysical investigations with other relevant datasets.
NOTE 1 The depth of interest for sub-seafloor mapping depends on the objectives of the investigation. For
offshore construction, the depths of investigation are typically in the range 1 m below seafloor to 200 m below
seafloor. Some methods for sub-seafloor mapping can also achieve much greater investigation depths, for
example for assessing geohazards for hydrocarbon well drilling.
There is a fundamental difference between seafloor mapping and sub-seafloor mapping: seafloor signal
resolution can be specified, while sub-seafloor signal resolution and penetration cannot. This document
therefore contains requirements for the use of certain techniques for certain types of seafloor mapping
and sub-seafloor mapping (similarly, requirements are given for certain aspects of data processing). If
other techniques can be shown to obtain the same information, with the same or better resolution and
accuracy, then those techniques may be used.
Mapping of pre-drilling well-site geohazards beneath the seafloor is part of the scope of this document.
NOTE 2 This implies depths of investigation that are typically 200 m below the first pressure-containment
casing string or 1 000 m below the seafloor, whichever is greatest. Mapping of pre-drilling well-site geohazards
is therefore the deepest type of investigation covered by this document.
In this document, positioning information relates only to the positioning of survey platforms, sources
and receivers. The processes used to determine positions of seafloor and sub-seafloor data points are
not covered in this document.
Guidance only is given in this document for the use of marine shear waves (A.8.3.3), marine surface
waves (A.8.3.4), electrical resistivity imaging (A.8.3.5) and electromagnetic imaging (A.8.3.6).
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2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 19901-8, Petroleum and natural gas industries — Specific requirements for offshore structures —
Part 8: Marine soil investigations
3  Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
abyssal water
water depths greater than 3 000 m
3.2
acoustic impedance
seismic velocity multiplied by density
Note 1 to entry: Compressional-wave impedance uses compressional-wave velocity, and shear-wave impedance
uses shear-wave velocity.
3.3
acoustic noise
unwanted acoustic signal
3.4
active tail buoy
buoy fitted with a global navigation satellite system transponder attached to the end of a streamer
3.5
airgun
seismic source that injects a bubble of highly compressed air into the water
Note 1 to entry: Whereas single airguns can be used, it is common practise to deploy and fire several airguns in
arrays to produce an acoustic pulse that has certain temporal and spatial characteristics.
3.6
aliasing
effect that causes signals to be misrepresented in recorded data as a result of undersampling
Note 1 to entry: Undersampling can be in time or spatial domain.
3.7
anisotropy
dependence of velocity on direction or upon angle of wave propagation
3.8
array
system of linked hydrophones or seismic sources arranged in a geometric pattern to increase sensitivity
and/or directionality and/or in the case of a seismic source, the pulse characteristics
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3.9
attenuation
reduction in amplitude or energy
Note 1 to entry: Attenuation in seismic data is related in part to soil conditions.
3.10
attribute
characteristic of a given object, structure or feature
Note 1 to entry: A seismic attribute is a quantity or property derived or extracted from seismic data that provides
specific information contained within the data as an aid in interpretation.
3.11
backscatter
amplitude of echo sounder energy reflected by the seafloor that can be processed into information
about seafloor features and texture
3.12
bandwidth
range of frequencies in an acoustic signal between the two half power points
Note 1 to entry: This corresponds with
...