IASPEI standard phase list

The following list of seismic phases was approved by the IASPEI Commission on Seismological Observation and Interpretation (CoSOI) and adopted by IASPEI on July 9th 2003.

More details may be found in Storchak et al. (2003) and Storchak et al. (2011):

Storchak, D.A., J. Schweitzer, P. Bormann (2003). The IASPEI Standard Seismic Phase List,Seismol. Res. Lett. 74, 6, 761-772, https://doi.org/10.1785/gssrl.74.6.761
Storchak, D.A., J. Schweitzer, P. Bormann (2011). Seismic phase names: IASPEI Standard, in Encyclopedia of Solid Earth Geophyiscs, 1162-1173, Ed. H.K. Gupta, Springer.

IASPEI Working Group members
Adams R.D.
Bormann P.
Engdahl R.E.
Havskov J.
Kennett B. L. N.
Schweitzer J.
Storchak D.A. (Chairman)

Contents
Crustal Phases
Mantle Phases
Core Phases
Near Source Surface Reflections (Depth Phases)
Surface Waves
Acoustic Phases
Amplitude Measurement Phases
Unidentified Arrivals

Notations used:
alt - acceptable alternative name;
old - name used in the past, no longer acceptable.

CRUSTAL PHASES
Pg At short distances, either an upgoing P wave from a source in the upper crust or a P wave bottoming in the upper crust. At larger distances also arrivals caused by multiple P-wave reverberations inside the whole crust with a group velocity around 5.8 km/s.
Pb (alt:P*) Either an upgoing P wave from a source in the lower crust or a P wave bottoming in the lower crust
Pn Any P wave bottoming in the uppermost mantle or an upgoing P wave from a source in the uppermost mantle
PnPn Pn free-surface reflection
PgPg Pg free-surface reflection
PmP P reflection from the outer side of the Moho
PmPN PmP multiple free surface reflection; N is a positive integer. For example, PmP2 is PmPPmP
PmS P to S reflection/conversion from the outer side of the Moho
Sg At short distances, either an upgoing S wave from a source in the upper crust or an S wave bottoming in the upper crust. At larger distances also arrivals caused by superposition of multiple S-wave reverberations and SV to P and/or P to SV conversions inside the whole crust.
Sb (alt:S*) Either an upgoing S wave from a source in the lower crust or an S wave bottoming in the lower crust
Sn Any S wave bottoming in the uppermost mantle or an upgoing S wave from a source in the uppermost mantle
SnSn Sn free-surface reflection
SgSg Sg free-surface reflection
SmS S reflection from the outer side of the Moho
SmSN SmS multiple free-surface reflection; N is a positive integer. For example, SmS2 is SmSSmS
SmP S to P reflection/conversion from the outer side of the Moho
Lg A wave group observed at larger regional distances and caused by superposition of multiple S-wave reverberations and SV to P and/or P to SV conversions inside the whole crust. The maximum energy travels with a group velocity of approximately 3.5 km/s
Rg Short-period crustal Rayleigh wave

MANTLE PHASES
P A longitudinal wave, bottoming below the uppermost mantle; also an upgoing longitudinal wave from a source below the uppermost mantle
PP Free-surface reflection of P wave leaving a source downward
PS P, leaving a source downward, reflected as an S at the free surface. At shorter distances, the first leg is represented by a crustal P wave.
PPP analogous to PP
PPS PP which is converted to S at the second reflection point on the free surface; travel time matches that of PSP
PSS PS reflected at the free surface
PcP P reflection from the core-mantle boundary (CMB)
PcS P converted to S when reflected from the CMB
PcPN PcP reflected from the free surface N-1 times; N is a positive integer. For example PcP2 is PcPPcP
Pz+P (alt:PzP) P reflection from outer side of a discontinuity at depth z; z may be a positive numerical value in km. For example P660+P is a P reflection from the top of the 660 km discontinuity.
Pz−P P reflection from inner side of a discontinuity at depth z. For example, P660−P is a P reflection from below the 660 km discontinuity, which means it is precursory to PP.
Pz+S (alt:PzS) P converted to S when reflected from outer side of discontinuity at depth z
Pz−S P converted to S when reflected from inner side of discontinuity at depth z
PScS P (leaving a source downward) to ScS reflection at the free surface
Pdif (old:Pdiff) P diffracted along the CMB in the mantle
S Shear wave, bottoming below the uppermost mantle; also an upgoing shear wave from a source below the uppermost mantle
SS Free surface-reflection of an S wave leaving a source downward
SP S, leaving a source downward, reflected as P at the free surface. At shorter distances the second leg is represented by a crustal P wave.
SSS analogous to SS
SSP SS converted to P when reflected from the free surface; travel time matches that of SPS.
SPP SP reflected at the free surface
ScS S reflection from the CMB
ScP S converted to P when reflected from the CMB
ScSN ScS multiple free-surface reflection; N is a positive integer. For example ScS2 is ScSScS
Sz+S (alt:SzS) S reflection from outer side of a discontinuity at depth z; z may be a positive numerical value in km. For example S660+S is an S reflection from the top of the 660 km discontinuity.
Sz−S S reflection from inner side of discontinuity at depth z. For example, S660−S is an S reflection from below the 660 km discontinuity, which means it is precursory to SS.
Sz+P (alt:SzP) S converted to P when reflected from outer side of discontinuity at depth z
Sz−P S converted to P when reflected from inner side of discontinuity at depth z
ScSP ScS to P reflection at the free surface
Sdif (old:Sdiff) S diffracted along the CMB in the mantle

CORE PHASES
PKP (alt:P') unspecified P wave bottoming in the core
PKPab (old:PKP2) P wave bottoming in the upper outer core; ab indicates the retrograde branch of the PKP caustic
PKPbc (old:PKP1) P wave bottoming in the lower outer core; bc indicates the prograde branch of the PKP caustic
PKPdf (alt:PKIKP) P wave bottoming in the inner core
PKPpre (old:PKhKP) a precursor to PKPdf due to scattering near or at the CMB
PKPdif P wave diffracted at the inner core boundary (ICB) in the outer core
PKS Unspecified P wave bottoming in the core and converting to S at the CMB
PKSab PKS bottoming in the upper outer core
PKSbc PKS bottoming in the lower outer core
PKSdf PKS bottoming in the inner core
P'P' (alt:PKPPKP) Free surface reflection of PKP
P'N (alt:PKPN) PKP reflected at the free surface N−1 times; N is a positive integer. For example P'3 is P'P'P'
Pz−P' PKP reflected from inner side of a discontinuity at depth z outside the core, which means it is precursory to P'P'; z may be a positive numerical value in km
P'S' (alt:PKPSKS) PKP converted to SKS when reflected from the free surface; other examples are P'PKS, P'SKP
PS' (alt:PSKS) P (leaving a source downward) to SKS reflection at the free surface
PKKP Unspecified P wave reflected once from the inner side of the CMB
PKKPab PKKP bottoming in the upper outer core
PKKPbc PKKP bottoming in the lower outer core
PKKPdf PKKP bottoming in the inner core
PNKP P wave reflected N−1 times from inner side of the CMB; N is a positive integer
PKKPpre A precursor to PKKP due to scattering near the CMB
PKiKP P wave reflected from the inner core boundary (ICB)
PKNIKP P wave reflected N−1 times from the inner side of the ICB
PKJKP P wave traversing the outer core as P and the inner core as S
PKKS P wave reflected once from inner side of the CMB and converted to S at the CMB
PKKSab PKKS bottoming in the upper outer core
PKKSbc PKKS bottoming in the lower outer core
PKKSdf PKKS bottoming in the inner core
PcPP' (alt:PcPPKP) PcP to PKP reflection at the free surface; other examples are PcPS', PcSP', PcSS', PcPSKP, PcSSKP
SKS (alt:S') unspecified S wave traversing the core as P
SKSac SKS bottoming in the outer core
SKSdf (alt:SKIKS) SKS bottoming in the inner core
SPdifKS (alt:SKPdifS) SKS wave with a segment of mantle side Pdif at the source and/or the receiver side of the ray path
SKP Unspecified S wave traversing the core and then the mantle as P
SKPab SKP bottoming in the upper outer core
SKPbc SKP bottoming in the lower outer core
SKPdf SKP bottoming in the inner core
S'S' (alt:SKSSKS) Free-surface reflection of SKS
S'N SKS reflected at the free surface N−1 times; N is a positive integer
S'z−S' SKS reflected from inner side of discontinuity at depth z outside the core, which means it is precursory to S'S'; z may be a positive numerical value in km
S'P' (alt:SKSPKP) SKS converted to PKP when reflected from the free surface; other examples are S'SKP, S'PKS
S'P (alt:SKSP) SKS to P reflection at the free surface
SKKS Unspecified S wave reflected once from inner side of the CMB
SKKSac SKKS bottoming in the outer core
SKKSdf SKKS bottoming in the inner core
SNKS S wave reflected N−1 times from inner side of the CMB; N is a positive integer
SKiKS S wave traversing the outer core as P and reflected from the ICB
SKJKS S wave traversing the outer core as P and the inner core as S
SKKP S wave traversing the core as P with one reflection from the inner side of the CMB and then continuing as P in the mantle
SKKPab SKKP bottoming in the upper outer core
SKKPbc SKKP bottoming in the lower outer core
SKKPdf SKKP bottoming in the inner core
ScSS' (alt:ScSSKS) ScS to SKS reflection at the free surface; other examples are: ScPS', ScSP', ScPP', ScSSKP, ScPSKP

NEAR SOURCE SURFACE REFLECTIONS (Depth phases)
pPy All P-type onsets (Py) as defined above, which resulted from reflection of an upgoing P wave at the free surface or an ocean bottom; WARNING: The character "y" is only a wild card for any seismic phase, which could be generated at the free surface. Examples are: pP, pPKP, pPP, pPcP etc.
sPy All Py resulting from reflection of an upgoing S wave at the free surface or an ocean bottom; For example: sP, sPKP, sPP, sPcP, etc
pSy All S-type onsets (Sy) as defined above, which resulted from reflection of an upgoing P wave at the free surface or an ocean bottom; for example: pS, pSKS, pSS, pScP, etc
sSy All Sy resulting from reflection of an upgoing S wave at the free surface or an ocean bottom; for example: sSn, sSS, sScS, sSdif, etc
pwPy All Py resulting from reflection of an upgoing P wave at the ocean's free surface
pmPy All Py resulting from reflection of an upgoing P wave from the inner side of the Moho
SURFACE WAVES
L Unspecified long period surface wave
LQ Love wave
LR Rayleigh wave
G Mantle wave of Love type
GN Mantle wave of Love type; N is integer and indicates wave packets traveling along the minor arcs (odd numbers) or major arc (even numbers) of the great circle
R Mantle wave of Rayleigh type
RN Mantle wave of Rayleigh type; N is integer and indicates wave packets traveling along the minor arcs (odd numbers) or major arc (even numbers) of the great circle
PL Fundamental leaking mode following P onsets generated by coupling of P energy into the waveguide formed by the crust and upper mantle
SPL S wave coupling into the PL waveguide; other examples are SSPL, SSSPL
ACOUSTIC PHASES
H A hydroacoustic wave from a source in the water, which couples in the ground
HPg H phase converted to Pg at the receiver side
HSg H phase converted to Sg at the receiver side
HRg H phase converted to Rg at the receiver side
I An atmospheric sound arrival, which couples in the ground
IPg I phase converted to Pg at the receiver side
ISg I phase converted to Sg at the receiver side
IRg I phase converted to Rg at the receiver side
T A tertiary wave. This is an acoustic wave from a source in the solid earth, usually trapped in a low velocity oceanic water layer called the SOFAR channel (SOund Fixing And Ranging)
TPg T phase converted to Pg at the receiver side
TSg T phase converted to Sg at the receiver side
TRg T phase converted to Rg at the receiver side
AMPLITUDE MEASUREMENT PHASES

The following set of amplitude measurement names refers to the IASPEI Magnitude Standard (see http://download.iaspei.org/commissions/CSOI/Summary_WG_recommendations_20130327.pdf), compliance to which is indicated by the presence of leading letter I. The absence of leading letter I indicates that a measurement is non-standard. Letter A indicates a measurement in nm made on a displacement seismogram, whereas letter V indicates a measurement in nm/sec made on a velocity seismogram.

IAML Displacement amplitude measured according to the IASPEI standard for local magnitude ML
IAMs_20 Displacement amplitude measured according to IASPEI standard for surface-wave magnitude MS(20)
IVMs_BB Velocity amplitude measured according to IASPEI standard for broadband surface-wave magnitude MS(BB)
IAmb Displacement amplitude measured according to IASPEI standard for short-period teleseismic body-wave magnitude mb
IVmB_BB Velocity amplitude measured according to IASPEI standard for broadband teleseismic body-wave magnitude mB(BB)
AX_IN Displacement amplitude of phase of type X (e.g., PP, S, etc), measured on an instrument of type IN (e.g., SP - short-period, LP - long-period, BB – broadband)
VX_IN Velocity amplitude of phase of type X and instrument of type IN (as above)
A Unspecified displacement amplitude measurement
V Unspecified velocity amplitude measurement
AML Displacement amplitude measurement for non-standard local magnitude
AMs Displacement amplitude measurement for non-standard surface-wave magnitude
Amb Displacement amplitude measurement for non-standard short-period body-wave magnitude
AmB Displacement amplitude measurement for non-standard medium to long-period body-wave magnitude
END Time of visible end of record for duration magnitude
UNIDENTIFIED ARRIVALS
x (old:i,e,NULL) unidentified arrival
rx (old:i,e,NULL) unidentified regional arrival
tx (old:i,e,NULL) unidentified teleseismic arrival
Px (old:i,e,NULL,(P),P?) unidentified arrival of P-type
Sx (old:i,e,NULL,(S),S?) unidentified arrival of S-type