ISO 22932-2:2020

Mining — Vocabulary — Part 2: Geology

This document specifies the geologic terms commonly used in mining. Only those terms that have a specific meaning in this field are included.

Exploitation minière — Vocabulaire — Partie 2: Géologie

General Information

• Status: Published
• Publication Date: 07-Jun-2020
• ICS: 01.040.73 - Mining and minerals (Vocabularies)
• ICS: 73.020 - Mining and quarrying
• Technical Committee: ISO/TC 82 - Mining
• Drafting Committee: ISO/TC 82/WG 8 - Terminology
• Current Stage: 9060 - Close of review
• Completion Date: 02-Dec-2030

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 22932-2
First edition
2020-06
Mining — Vocabulary —
Part 2:
Geology
Exploitation minière — Vocabulaire —
Partie 2: Géologie
Reference number
©
ISO 2020
© ISO 2020
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 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General terms . 1
3.2 Physical geology . 6
3.3 Mineralogy . 7
3.4 Petrology . 8
3.5 Historical geology .17
3.6 Topography .19
3.7 Structural geology and tectonics .20
3.8 Geomorphology .33
3.9 Geochemistry.34
3.10 Geophysics .35
3.11 Geohydrology .36
3.12 Hydrology .37
3.13 Economic geology .40
3.14 Soils .42
Bibliography .44
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. 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. 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 82, Mining.
A list of all parts in the ISO 22932 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.
iv © ISO 2020 – All rights reserved

Introduction
The ISO 22932 series has been prepared in order to standardize and to co-ordinate the global use of
technical terms in mining, for the benefice of the experts working on different types of mining activities.
The need for the ISO 22932 series arose from the widely varying interpretation of terms used within
the industry and the prevalent use of more than one synonym.
INTERNATIONAL STANDARD ISO 22932-2:2020(E)
Mining — Vocabulary —
Part 2:
Geology
1 Scope
This document specifies the geologic terms commonly used in mining. Only those terms that have a
specific meaning in this field are included.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
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 General terms
3.1.1
bedrock
solid rock underlying superficial deposits (3.4.3.16)
Note 1 to entry: See also saddle reef (3.13.11).
[SOURCE: BS 3618-5:1971]
3.1.2
economic geology
study and analysis of formations (3.7.22) and materials that can be useful or profitable to man
Note 1 to entry: These materials can be fuels, metallic minerals (3.13.4), nonmetallic minerals (3.13.4), water and
geothermal resources.
Note 2 to entry: For additional terms related to economic geology, see 3.13.
3.1.3
geochemistry
study of the relative and absolute abundances of the elements and their nuclides (isotopes) in the Earth,
including the distribution and migration of the individual elements or suites of elements in the various
envelopes of the Earth
Note 1 to entry: The envelopes of the Earth are the atmosphere, the hydrosphere, the lithosphere, etc.
Note 2 to entry: For additional terms related to geochemistry, see 3.9.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
2 to entry added.]
3.1.4
geohydrology
study of hydraulics pertinent to the flow of water and similar liquids through soils (3.1.19) and rocks
Note 1 to entry: For additional terms related to geohydrology, see 3.11.
[SOURCE: BS 3618-5:1971, modified - Note 1 to entry added.]
3.1.5
geology
study of the planet Earth, the materials of which it is made, the processes that act on these materials,
the products formed, and the history of the planet and its life forms since its origin
Note 1 to entry: Geology considers the physical forces that act on the Earth, the chemistry of its constituent
materials, and the biology of its past inhabitants as revealed by fossils. Clues on the origin of the planet are sought
in a study of the Moon and other extraterrestrial bodies. The knowledge thus obtained is placed in the service
of humans to aid in discovery of minerals (3.13.4) and fuels of value in the Earth's crust, to identify geologically
stable sites for major structures (3.4.1.4), and to provide foreknowledge of some of the dangers associated with
the mobile forces of a dynamic Earth.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.6
geomorphology
science that treats the general configuration of the Earth's surface (3.1.23), specifically the study of the
classification, description, nature, origin, and development of present landforms and their relationships
to underlying structures (3.4.1.4), and of the history of geologic changes as recorded by these surface
features
Note 1 to entry: For additional terms related to geomorphology, see 3.8.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
1 to entry added.]
3.1.7
geophysics
branch of physics dealing with the Earth using specific physical phenomena in order to elucidate
processes of dynamic geology (3.1.5) and physical geography
Note 1 to entry: The term "Earth" includes atmosphere and hydrosphere.
Note 2 to entry: The physical phenomena dealt with include seismic, gravitational, electric, thermal, radiometric
and magnetic.
Note 3 to entry: Earth sciences such as geodesy (3.8.4), geology, seismology (3.7.10), meteorology, oceanography,
and magnetism make use of physics in collecting and interpreting Earth data.
Note 4 to entry: Methods applying geophysics have been applied successfully to the identification of underground
structures (3.4.1.4) in the Earth and to the search of structures of a particular type, for example those associated
with oil bearing sands.
Note 5 to entry: For additional terms related to geophysics, see 3.10.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
5 to entry added.]
3.1.8
historical geology
major branch of geology (3.1.5) concerned with the evolution of the Earth and its life forms from its
origins to the present day, involving investigations into stratigraphy, paleontology, and geochronology,
as well as the consideration of paleoenvironments, glacial periods, and plate-tectonic motions
Note 1 to entry: It is complementary to physical geology (3.1.15). Not to be confused with the history of geology.
2 © ISO 2020 – All rights reserved

Note 2 to entry: For additional terms related to historical geology, see 3.5.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
2 to entry added.]
3.1.9
hydrology
study of the movement of water on and within the Earth’s crust
Note 1 to entry: See also hydrogeology (3.11.4).
Note 2 to entry: For additional terms related to hydrology, see 3.12.
[SOURCE: BS 3618-5:1971, modified - Note 2 to entry added.]
3.1.10
ironstone
rock containing a substantial proportion of an iron compound, or any iron ore from which the metal can
be smelted commercially; specifically, an iron-rich sedimentary rock (3.4.3), either deposited directly as
a ferruginous sediment or resulting from chemical replacement
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.11
mineralogy
study of minerals (3.13.4), including their formation, occurrence, use, properties, composition, and
classification
Note 1 to entry: For additional terms related to mineralogy, see 3.3.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
1 to entry added.]
3.1.12
mining geology
geological aspects of mineral (3.13.4) deposits related to mining activities
Note 1 to entry: Its objectives, besides studying the geologic structures (3.4.1.4) in place and their continuity in
space, are the modes of formation and the occurrence of mineral deposits and their discovery, in particular.
3.1.13
nongraded sediment
bed (3.4.1.1) detrital sediment, loose or cemented, containing notable amounts of more than one grade,
e.g. loam or boulder clay (3.14.2)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.14
petrology
study of the origin, chemical and mineral (3.13.4) composition, structure (3.4.1.4), and alteration
(3.4.4.1) of rocks
Note 1 to entry: For additional terms related to petrology, see 3.4.
[SOURCE: BS 3618-5:1971, modified - Note 1 to entry added.]
3.1.15
physical geology
broad division of geology (3.1.5) concerned with the processes and forces involved in the inorganic
evolution of the Earth and its morphology, and with its constituent minerals (3.13.4), rocks, magmas,
and core materials
Note 1 to entry: For additional terms related to physical geology, see 3.2.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
1 to entry added.]
3.1.16
rank
position of a coal (3.4.3.1) relative to other coals in the coalification series from brown coal (low rank)
to anthracite (3.4.4.2) (high rank), indicating its maturity in terms of its general chemical and physical
properties
[SOURCE: BS 3618-5:1971]
3.1.17
seam
layer or bed (3.4.1.1) of mineral (3.13.4)
Note 1 to entry: This term can also be used for minerals.
3.1.18
segregate
to separate from the general mass, and collect together or become concentrated at a particular place or
in a certain region
Note 1 to entry: Particles can segregate such as in the process of crystallization or solidification.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.19
soil
all unconsolidated materials above bedrock (3.1.1)
Note 1 to entry: For additional terms related to soils, see 3.14.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
1 to entry added.]
3.1.20
subsurface geology
underground geology
geology (3.1.5) and correlation (3.5.2) of rock formations (3.7.22), structures (3.4.1.4), and other
features beneath the land or sea-floor surface (3.1.23) as revealed or inferred by exploratory drilling,
underground workings, and geophysical methods
Note 1 to entry: Usually implies direct evidence derived from shafts, wells, and borings, or obtained by
geophysical methods.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.21
smut
thin band of soft, inferior coal (3.4.3.1)
[SOURCE: BS 3618-5:1971]
3.1.22
structural geology
branch of geology (3.1.5) that deals with the form, arrangement, and internal structure (3.4.1.4) of
the rocks, and especially with the description, representation, and analysis of structures, chiefly on a
moderate to small scale
Note 1 to entry: The subject is similar to tectonics (3.1.26), but the latter is generally used for the broader regional
or historical phases.
Note 2 to entry: For additional terms related to structural geology, see 3.7.
4 © ISO 2020 – All rights reserved

[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
2 to entry added.]
3.1.23
surface
boundary surface between one bed (3.4.1.1) or mass of rock and another immediately adjacent
EXAMPLE Bedding surface, fault (3.7.17) surface, surface of unconformity (3.5.8), surface of igneous compact.
Note 1 to entry: This term can also designate an imaginary surface, such as the axial surface of a fold (3.7.21).
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.24
surface geology
geology (3.1.5) and correlation (3.5.2) of rock formations (3.7.22), structures (3.4.1.4), and other features
as seen at the Earth's surface (3.1.23)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.25
surficial geology
geology (3.1.5) of surficial deposits, including soils (3.1.19)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.1.26
tectonics
branch of geology (3.1.5) dealing with the broad architecture of the outer part of the Earth, i.e., the
regional assembling of structural or deformational features, the study of their mutual relations, origin,
and historical evolution
Note 1 to entry: It is closely related to structural geology (3.1.22), with which it overlaps, although tectonics
generally deals with larger features.
Note 2 to entry: For additional terms related to tectonics, see 3.7.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified - Note
2 to entry added.]
3.1.27
topography
general configuration of a land surface (3.1.23) or any part of the Earth's surface, including its relief and
the position of its natural and manmade features
Note 1 to entry: The natural or physical surface features of a region, considered collectively as to form the
features revealed by the contour (3.6.3) lines of a map. In nongeologic usage, the term includes manmade features
(such as are shown on a topographic map).
Note 2 to entry: For additional terms related to topography, see 3.6.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996, modified -
Note2 to entry added.]
3.1.28
transportation
shifting of material from one place to another on the Earth's surface (3.1.23) by moving water, ice, or air
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2 Physical geology
3.2.1
catastrophe
sudden, violent change in the physical conditions of the Earth's surface (3.1.23)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.2
contact bed
bed (3.4.1.1) lying next to or in contact with a formation (3.7.22) of different character
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.3
field geology
field work
geology (3.1.5) as practiced by direct observation in the field; original, primary reconnaissance
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.4
geologic drilling
drilling done primarily to obtain information from which the geology (3.1.5) of the formations (3.7.22)
penetrated can be determined
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.5
geological province
area throughout which geological history has been essentially the same or one that is characterized by
particular structural or physiographic features
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.6
measures
series of beds or strata, nowadays generally limited to rock within the coal (3.4.3.1) measures
[SOURCE: BS 3618-5:1971]
3.2.7
rake vein
steeply inclined metalliferous lode (3.13.3) or vein (3.13.13)
[SOURCE: BS 3618-5:1971]
3.2.8
rider
mass of country rock (3.3.5) enclosed in a lode (3.13.3)
Note 1 to entry: Compare with 3.4.1.3 and 3.13.9.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.9
shell bed
bed (3.4.1.1) containing abundant fossil shells
[SOURCE: BS 3618-5:1971]
6 © ISO 2020 – All rights reserved

3.2.10
slump bedding
disturbed bedding, specifically deformed bedding produced by subaqueous slumping or lateral
movement of newly deposited sediment
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.2.11
stringer
mineral (3.13.4) veinlet or filament, usually one of a number, occurring in a discontinuous subparallel
pattern in host rock
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.3 Mineralogy
3.3.1
barren ground
unmineralised strata
3.3.2
blackband ironstone
bed (3.4.1.1) of ironstone (3.1.10) containing sufficient carbonaceous (3.4.3.14) matter to make it self-
calcining
[SOURCE: BS 3618-5:1971]
3.3.3
clay band ironstone
impure argillaceous (3.14.1) carbonate of iron occurring in sand stones and shales (3.4.3.34), either as
definite layers or as nodules
[SOURCE: BS 3618-5:1971]
3.3.4
cleavage
in a crystalline mineral (3.13.4), one or more series of parallel planes along which the mineral tends to split
[SOURCE: BS 3618-5:1971]
3.3.5
country rock
rock adjacent to a mineral (3.13.4) deposit or igneous intrusion (3.4.2.7) or other geologic features
[SOURCE: BS 3618-5:1971]
3.3.6
exsolution
process whereby an initially homogeneous solid solution separates into two (or possibly more) distinct
crystalline phases without addition or removal of material, i.e., without change in the bulk composition
Note 1 to entry: It generally, though not necessarily, occurs on cooling.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.3.7
fluid inclusion
cavity, with or without negative crystal faces, containing one or two fluid phases, and possibly one or
more minute crystals, in a host crystal
Note 1 to entry: If two fluid phases are present, the vapor phase (bubble) can show Brownian motion.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.3.8
matrix
finer grained material between the larger particles of a rock or the material surrounding a fossil or
mineral (3.13.4)
[SOURCE: BS 3618-5:1971]
3.3.9
polymorph
minerals (3.13.4) that have the same chemical composition, but different crystal structures (3.4.1.4)
EXAMPLE 1 Kyanite, andalusite, and sillimanite.
EXAMPLE 2 Quartz, tridymite, cristobalite, coesite, and stishovite.
3.3.10
polymorphism
characteristic of a chemical compound to crystallize in more than one crystal class
Note 1 to entry: See polymorph (3.3.9).
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4 Petrology
3.4.1 General terms
3.4.1.1
bed
layer of rock or mineral (3.13.4)
[SOURCE: BS 3618-5:1971]
3.4.1.2
lithology
character of a rock expressed in terms of its mineral (3.13.4) composition, structure (3.4.1.4), grain size,
color and arrangement of its component parts
[SOURCE: BS 3618 -5:1971, modified - definition reworded.]
3.4.1.3
rider
bed (3.4.1.1) in a coal (3.4.3.1) seam (3.1.17)
Note 1 to entry: Compare with 3.2.8 and 3.13.9.
EXAMPLE Shale (3.4.3.34) or mudstone (3.4.3.30).
3.4.1.4
structure
larger feature of a rock mass and total sum of such features
EXAMPLE Bedding, flow banding, jointing, cleavage (3.7.8), shear, fault (3.7.17) and brecciation.
3.4.1.5
texture
general physical appearance or character of a rock, including the geometric aspects of, and the mutual
relations among, its component particles or crystals
EXAMPLE 1 Size, shape, and arrangement of the constituent elements of a sedimentary rock (3.4.3).
8 © ISO 2020 – All rights reserved

EXAMPLE 2 Crystallinity, granularity, and fabric of the constituent elements of an igneous rock (3.4.2).
Note 1 to entry: The term is applied to the smaller (megascopic or microscopic) features as seen on a smooth
surface (3.1.23) of a homogeneous rock or mineral (3.13.4) aggregate. The term structure (3.4.1.4) is generally
used for the larger features of a rock. The two terms should not be used synonymously, although certain textural
features can parallel major structural features.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2
igneous rock
rock formed by the solidification of molten material that originated within the Earth
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.1
agglomerate
naturally cemented unstratified mass of coarse volcanic fragments
[SOURCE: BS 3618-5:1971]
3.4.2.2
volcanic ash
fine loose debris ejected in volcanic eruptions
Note 1 to entry: It gives rise to tuff (3.4.2.17) when compacted.
[SOURCE: BS 3618-5:1971]
3.4.2.3
batholith
bathylith
large, generally discordant (3.5.3) plutonic mass that has more than 104 km of surface (3.1.23) exposure
and no known floor
Note 1 to entry: Its formation (3.7.22) is believed by most investigators to involve magmatic processes.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.4
dolerite
whin
dark crystalline igneous rock (3.4.2) forming intrusions (3.4.2.7) such as dykes (3.4.2.5) and sills
(3.4.2.16)
[SOURCE: BS 3618-5:1971]
3.4.2.5
dyke
more or less perpendicular wall-like igneous mass intruded into other rocks
[SOURCE: BS 3618-5:1971]
3.4.2.6
hard-rock geology
colloquial term for geology (3.1.5) of igneous rocks (3.4.2) and metamorphic rocks (3.4.4), as opposed to
soft-rock geology (3.4.3.37)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.7
intrusion
mass of igneous rock (3.4.2) which, while molten, was forced into or between other rocks
[SOURCE: BS 3618-5:1971]
3.4.2.8
laccolith
concordant (3.4.4.12) igneous intrusion (3.4.2.7) with a known or assumed flat floor and a postulated,
dike-like feeder commonly thought to be beneath its thickest point
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.9
lopolith
large, concordant (3.4.4.12), typically layered igneous intrusion (3.4.2.7), of planoconvex or lenticular
shape, that is sunken in its central part owing to sagging of the underlying country rock (3.3.5)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.10
phacolith
concordant (3.4.4.12) intrusion (3.4.2.7) in the crest of an anticline (3.7.1) and trough of a syncline (3.7.51)
that, in a cross section, has the shape of a doubly convex lens
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.11
phenocryst
large crystal or mineral (3.13.4) grains floating in the matrix (3.3.8) or groundmass of a porphyry
(3.4.2.14)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.12
pluton
body of medium- to coarse-grained igneous rock (3.4.2) that formed beneath the surface (3.1.23) by
crystallization of a magma
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.13
porphyritic
texture (3.4.1.5) of an igneous rock (3.4.2) in which larger crystals [phenocrysts (3.4.2.11)] are set in a
finer-grained groundmass, which can be crystalline or glassy or both
Note 1 to entry: Also, said of a rock with such texture, or of the mineral (3.13.4) forming the phenocrysts.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.14
porphyry
porphyritic igneous rock
igneous rock (3.4.2) of any composition that contains conspicuous phenocrysts (3.4.2.11) in a fine-
grained groundmass
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
10 © ISO 2020 – All rights reserved

3.4.2.15
pyroclastic
produced by explosive or aerial ejection of ash (3.4.3.4), fragments, and glassy material from a
volcanic vent
Note 1 to entry: It applies to the rocks and rock layers as well as to the texture (3.4.1.5) so formed.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.2.16
sill
intrusive sheet of igneous rock (3.4.2) parallel or nearly parallel to the general stratification
[SOURCE: BS 3618-5:1971]
3.4.2.17
tuff
compacted fine volcanic ash (3.4.2.2) and dust
[SOURCE: BS 3618-5:1971]
3.4.2.18
vitrophyric
porphyritic (3.4.2.13) igneous rock (3.4.2) having a glassy groundmass
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3
sedimentary rock
rock formed from materials derived from the weathering of previously existing rock masses
[SOURCE: BS 3618-5:1971]
3.4.3.1
coal
combustible sedimentary rock (3.4.3), formed from variously altered plant remains
[SOURCE: BS 3618-5:1971]
3.4.3.1.1
anthracology
branch of geology (3.1.5) dealing with the physical constitution of coal (3.4.3.1) in much the same way
that petrography deals with the mineral (3.13.4) composition of rocks
Note 1 to entry: It is concerned with the physical variations in coal that make it possible to classify coal material
by types.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.2
alluvium
deposits, normally unconsolidated, made by streams in channels and over their flood plains and deltas
[SOURCE: BS 3618-5:1971]
3.4.3.3
arenaceous
said of a sediment or sedimentary rock (3.4.3) consisting wholly or in part of sand-sized fragments, or
having a sandy texture (3.4.1.5) or the appearance of sand
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.4
ash
inorganic residue after the incineration of coal (3.4.3.1) to constant weight under standard conditions
Note 1 to entry: In general, it differs in weight and composition from the original mineral (3.13.4) matter.
[SOURCE: BS 3618-5:1971]
3.4.3.5
basement complex
series of rocks generally with complex structure (3.4.1.4) beneath the dominantly sedimentary rocks (3.4.3)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.6
bedding plane
interface between two adjacent beds of sedimentary rock (3.4.3)
[SOURCE: BS 3618-5:1971]
3.4.3.7
bituminous coal
coal (3.4.3.1) other than anthracite (3.4.4.2) and low-volatile coal on the one hand and lignite (3.4.3.28)
on the other
[SOURCE: BS 3618-5:1971]
3.4.3.8
boghead coal
coal (3.4.3.1) resembling cannel coal (3.4.3.12) in physical appearance and properties, but distinguished
microscopically by the presence of the remains of algae
[SOURCE: BS 3618-5:1971]
3.4.3.9
breccia
rock consisting of broken angular, unworn fragments held together by a natural cement
[SOURCE: BS 3618-5:1971]
3.4.3.10
buried channel
old channel filled and concealed by glacial or other superficial deposits (3.4.3.16)
[SOURCE: BS 3618-5:1971]
3.4.3.11
burnt coal
coal (3.4.3.1) altered by heat from an igneous intrusion (3.4.2.7) within or near the seam (3.1.17)
[SOURCE: BS 3618-5:1971]
3.4.3.12
cannel coal
strong, non-banded coal (3.4.3.1) with a satin sheen or wax lustre, showing a conchoidal fracture;
distinguished microscopically from boghead coal (3.4.3.8) by the presence of the remains of spores
Note 1 to entry: Generally having high volatile matter content and readily ignitable.
[SOURCE: BS 3618-5:1971]
12 © ISO 2020 – All rights reserved

3.4.3.13
cank
hard, dark-grey massive rock consisting largely of ankerite
Note 1 to entry: Cank is found in some coal (3.4.3.1) measures (3.2.6) marine beds.
[SOURCE: BS 3618-5:1971]
3.4.3.14
carbonaceous
consisting of or containing coal (3.4.3.1) or coal-like material
Note 1 to entry: The term is used especially of shale (3.4.3.34) with particles of such material distributed
throughout the mass.
[SOURCE: BS 3618-5:1971]
3.4.3.15
cauldron bottom
concretionary mass surrounded by glossy surfaces (3.1.23) and usually occurring in the roof of a coal
(3.4.3.1) seam (3.1.17)
[SOURCE: BS 3618-5:1971]
3.4.3.16
superficial deposit
most recent deposit, generally unconsolidated (e.g. most, peat, sand, gravel, silt (3.4.3.35), mud, etc.)
lying above the rockhead (3.13.10)
[SOURCE: BS 3618-5:1971]
3.4.3.17
coal balls
calcareous concretions of mineralized plant debris occurring in certain coal (3.4.3.1) seams (3.1.17)
[SOURCE: BS 3618-5:1971]
3.4.3.18
conglomerate
coarse-grained sedimentary rock (3.4.3) composed of rounded fragments embedded in a matrix (3.3.8)
of cementing material such as silica
3.4.3.19
crop coal
oxidized coal (3.4.3.1) found near the surface (3.1.23)
[SOURCE: BS 3618-5:1971]
3.4.3.20
cross bedding
laminations, in a bed (3.4.1.1) of sedimentary rock (3.4.3), which are inclined to the general stratification
Note 1 to entry: See Figure 1.
[SOURCE: BS 3618-5:1971]
Figure 1 — Cross bedding
3.4.3.21
dirt band
thin stratum of shale (3.4.3.34) or other inorganic rock material in a coal (3.4.3.1) seam (3.1.17)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.22
splint coal
hard coal (3.4.3.1) with a dull lustre and uneven fracture
[SOURCE: BS 3618-5:1971]
3.4.3.23
drift
superficial deposit
EXAMPLE Boulder clay (3.14.2), glacial gravel, alluvium (3.4.3.2), peat.
[SOURCE: BS 3618-5:1971]
3.4.3.24
evaporite
rock, formed by the evaporation of lakes or seas
EXAMPLE Anhydrite, rock salt, potash salts.
[SOURCE: BS 3618-5:1971]
3.4.3.25
freestone
uniform, fine-grained sandstone (3.4.3.33) or limestone (3.4.3.29) that can be readily sawn and shaped
[SOURCE: BS 3618-5:1971]
3.4.3.26
ganister
compact, highly siliceous, sedimentary rock (3.4.3), often containing plant remains
[SOURCE: BS 3618-5:1971]
14 © ISO 2020 – All rights reserved

3.4.3.27
intrusion
mass of sedimentary rock (3.4.3) occurring in a coal (3.4.3.1) seam (3.1.17)
[SOURCE: BS 3618-5:1971]
3.4.3.28
lignite
coal (3.4.3.1) of low rank (3.1.16) with a high inherent moisture and volatile matter
Note 1 to entry: In this general sense, lignite can be sub-divided into black lignite, brown lignite and brown coal.
[SOURCE: BS 3618-5:1971]
3.4.3.29
limestone
sedimentary rock (3.4.3) consisting predominantly of calcium carbonate
3.4.3.30
mudstone
indurated sedimentary rock (3.4.3) consisting largely of clay (3.14.2) minerals (3.13.4), with little or no
fissility
[SOURCE: BS 3618-5:1971]
3.4.3.31
rashings
carbonaceous (3.4.3.14) shale (3.4.3.34) with coal (3.4.3.1) streaks
[SOURCE: BS 3618-5:1971]
3.4.3.32
rashings
soft shale (3.4.3.34), normally carbonaceous (3.4.3.14)
Note 1 to entry: Rashings often are associated with coal (3.4.3.1) seams (3.1.17) containing sheared coal
fragments.
[SOURCE: BS 3618-5:1971]
3.4.3.33
sandstone
medium-grained clastic sedimentary rock (3.4.3) composed of fragments of sand size set in a fine-
grained matrix (3.3.8) [silt (3.4.3.35) or clay (3.14.2)] and more or less firmly united by a cementing
material (commonly silica, iron oxide, or calcium carbonate)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.34
shale
fine-grained detrital sedimentary rock (3.4.3), formed by the consolidation (especially by compression)
of clay (3.14.2), silt (3.4.3.35), or mud
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.3.35
silt
fine grained sediment having a particle size intermediate between that of fine sand and clay (3.14.2)
[SOURCE: BS 3618-5:1971]
3.4.3.36
siltstone
consolidated silt (3.4.3.35).
[SOURCE: BS 3618-5:1971]
3.4.3.37
soft-rock geology
colloquial term for geology (3.1.5) of sedimentary rocks (3.4.3), as opposed to hard-rock geology (3.4.2.6)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4
metamorphic rock
rock altered by the action of heat, pressure, or migrating fluids, acting separately or together
[SOURCE: BS 3618-5:1971]
3.4.4.1
alteration
change in the mineralogic composition of a rock brought about by physical or chemical means, especially
by the action of hydrothermal solutions
Note 1 to entry: It can be a secondary, i.e., supergene, change in a rock or mineral (3.13.4).
Note 2 to entry: Alteration is sometimes considered as a phase of metamorphism (3.4.4.9), but is usually
distinguished from it because of being milder and more localized than metamorphism is generally thought to be.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.2
anthracite
coal (3.4.3.1) of the highest rank (3.1.16) having volatile matter in the region of 100 g/Kg or less
3.4.4.3
contact metamorphism
metamorphism (3.4.4.9) taking place in rocks at or near their contact with a body of igneous rock (3.4.2)
Note 1 to entry: Metamorphic changes are effected by the heat and materials emanating from the magma and by
some deformation connected with the emplacement of the igneous mass.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.4
dynamometamorphism
dynamic metamorphism
metamorphism (3.4.4.9) resulting from the processes and effects of orogenic movements and differential
stresses in producing new rocks from old, with marked structural and mineralogical changes due to
crushing and shearing at low temperatures and extensive recrystallization at higher temperatures
Note 1 to entry: It can involve large areas of the Earth's crust, i.e., be regional in character.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.5
gneiss
foliated rock formed by regional metamorphism (3.4.4.10), in which bands or lenticles of granular
minerals (3.13.4) alternate with bands or lenticles in which minerals having flaky or elongate prismatic
habits predominate
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
16 © ISO 2020 – All rights reserved

3.4.4.6
hydrolysis
decomposition of organic compounds by interaction with water; either cold, or on heating alone, or in
the presence of acids or alkalies
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.7
hydrothermal alteration
alteration (3.4.4.1) of rocks or minerals (3.13.4) by the reaction of hydrothermal fluid with preexisting
solid phases
3.4.4.8
marble
metamorphic rock (3.4.4) composed essentially of calcite, dolomite, or a combination of the two, with a
fine- to coarse-grained crystalline texture (3.4.1.5)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.9
metamorphism
mineralogical, chemical, and structural adjustment of solid rocks to physical and chemical conditions
that have generally been imposed at depth below the surface (3.1.23) zones of weathering and
cementation, and that differ from the conditions under which the rocks in question originated
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.10
regional metamorphism
metamorphism (3.4.4.9) affecting an extensive region, as opposed to local or contact metamorphism
(3.4.4.3)
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.11
slate
compact, fine-grained metamorphic rock (3.4.4) that possesses slaty cleavage (3.7.8) and hence can be
split into slabs and thin plates
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.4.4.12
concordant
metamorphic processes at the extreme upper range of temperatures and pressures,
at which partial to complete fusion of the affected rocks takes place and magma is produced
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.5 Historical geology
3.5.1
concordant
radiometric ages, either determined by more than one method, that are in
agreement within the analytical precision for the determining methods, or given by coexisting minerals
(3.13.4), determined by the same method, that are in agreement
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.5.2
correlation
determination of the equivalence in the stratigraphical position of beds in separated areas
[SOURCE: BS 3618-5:1971]
3.5.3
discordant
contact between an igneous intrusion (3.4.2.7) and the country rock (3.3.5) that is not parallel to the
foliation or bedding planes (3.4.3.6) of the latter
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.5.4
inlier
area of older rocks surrounded by younger rocks
[SOURCE: BS 3618-5:1971]
3.5.5
outlier
area of younger rocks surrounded by older rocks
[SOURCE: BS 3618-5:1971]
3.5.6
stratabound
mineral (3.13.4) deposit confined to a single stratigraphic unit
Note 1 to entry: The term can refer to a stratiform (3.5.7) deposit, to variously oriented orebodies contained
within the unit, or to a deposit containing veinlets and alteration (3.4.4.1) zones that may or may not be strictly
conformable with bedding.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.5.7
stratiform
special type of strata-bound deposit in which the desired rock or ore constitutes, or is strictly
coextensive with, one or more sedimentary, metamorphic, or igneous layers
EXAMPLE Beds of salt or iron oxide, or layers rich in chromite or platinum, in a layered igneous complex.
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
3.5.8
unconformity
substantial break in the continuity of deposition, where one rock formation (3.7.22) is overlain by
another that is not the next in geological succession
[SOURCE: BS 3618-5:1971]
3.5.8.1
angular unconformity
unconformity (3.5.8) in which the older underlying strata dip (3.7.13) at a different angle (generally
steeper) than the younger overlying strata
[SOURCE: Dictionary of Mining, Mineral and Related Terms, U.S. Bureau of Mines, 1996]
18 ©
...