mec 
Logical Entity Name  mec 
Default Table Name  mec 
Definition  Summary information on a moment tensor 

mec Attributes 
Attribute/Logical Rolename  Domain  Datatype  NULL  Definition 
mecid(PK)    NUMERIC(15, 0)  NO  Mechanism identification. Each mechanism is assigned a unique positive integer which identifies it in the database 
oridin(FK)    NUMERIC(15, 0)  YES  Input origin. This attribute holds the origin identifier, orid, that points to the origin from which the mechanism was computed 
oridout(FK)    NUMERIC(15, 0)  YES  Output origin. This attribute holds the origin identifier, orid, that points to the origin computed from the mechanism 
magid(FK)    NUMERIC(15, 0)  YES  Magnitude identifier. This key is used to identify a magnitude in the Netmag relation. It is required for every magnitude 
commid    NUMERIC(15, 0)  YES  Comment identification. This is a key used to point to free-form comments entered in the Remark relation. These comments store additional information about a tuple in another relation. Within the Remark relation, there may be many tuples with the same commid and different lineno, but the same commid will appear in only one other tuple among the rest of the relations in the database 
mechtype    VARCHAR(2)  YES  Mechanism type 
mecalgo    VARCHAR(15)  YES  This attribute represents the algorithm used to compute the mechanism (TDMT,TMTS=Dreger's code; FPFIT=fpfit; SMTINV=Pasyanos code) 
scalar    DOUBLE PRECISION  YES  Seismic scalar moment (no value stored for fpfit) 
erscalar    DOUBLE PRECISION  YES  Error in scalar moment. This is the standard deviation of the scalar moment 
tft    VARCHAR(8)  YES  Type of source time function. Used to specify if time function and source half-duration are assumed, derived, or determined 
tfd    DOUBLE PRECISION  YES  Duration of the source time function 
mxx    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
myy    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
mzz    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
mxy    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
mxz    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
myz    DOUBLE PRECISION  YES  Moment tensor elements. Given in Aki convention 
smxx    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
smyy    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
smzz    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
smxy    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
smxz    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
smyz    DOUBLE PRECISION  YES  Uncertainties in moment tensor elements 
srcduration    NUMERIC(6, 3)  YES  Source half-duration 
auth    VARCHAR(15)  NO  The auth field specifies the source of the information. This may be a network identifier (FDSN or otherwise), or any other string indicating the source of the information in the record 
subsource    VARCHAR(8)  YES  A second identifier to specify the system or process that derived the data. e.g., the origin's AUTH is CI, but the subsource (the solution) was computed by JIGGLE 
strike1    NUMERIC(3, 0)  YES  Strike of fault plane 1 from the best double couple 
dip1    NUMERIC(3, 0)  YES  Dip of fault plane 1 from the best double couple 
rake1    NUMERIC(4, 0)  YES  Rake of fault plane 1 from the best double couple solution 
strike2    NUMERIC(3, 0)  YES  Strike of fault plane 2 from the best double couple 
dip2    NUMERIC(2, 0)  YES  Dip of fault plane 2 from the best double couple 
rake2    NUMERIC(4, 0)  YES  Rake of fault plane 2 from the best double couple solution 
unstrike1    NUMERIC(6, 3)  YES  Uncertainty in strike 1 
undip1    NUMERIC(5, 3)  YES  Uncertainty in dip 1 
unrake1    NUMERIC(6, 3)  YES  Uncertainty in rake 1 
unstrike2    NUMERIC(6, 3)  YES  Uncertainty in strike 2 
undip2    NUMERIC(5, 3)  YES  Uncertainty in dip 2 
unrake2    NUMERIC(6, 3)  YES  Uncertainty in rake 2 
eigenp    DOUBLE PRECISION  YES  Eigen value of compressional axis in the principal axes representation of the best double couple 
plungep    NUMERIC(2, 0)  YES  Plunge of the compressional axis in the principal axes representation of the best double couple 
strikep    NUMERIC(3, 0)  YES  Strike of compressional axis in the principal axes representation of the best double couple 
eigenn    DOUBLE PRECISION  YES  Eigen value of null axis in the principal axes representation of the best double couple 
plungen    NUMERIC(2, 0)  YES  Plunge of the null axis in the principal axes representation of the best double couple 
striken    NUMERIC(3, 0)  YES  Strike of null axis in the principal axes representation of the best double couple 
eigent    DOUBLE PRECISION  YES  Eigen value of tension axis in the principal axes representation of the best double couple 
plunget    NUMERIC(2, 0)  YES  Plunge of the tension axis in the principal axes representation of the best double couple 
striket    NUMERIC(3, 0)  YES  Strike of tension axis in the principal axes representation of the best double couple 
nsta    NUMERIC(5, 0)  YES  This quantity is the number of observations with non-zero input weights used to compute the mechanism. For CW=nsta, for FPFIT=nPobs, for HASH=nobs 
pvr    NUMERIC(5, 0)  YES  Goodness of fit. For TDMT this is percent variance reduction; for FPFIT this is (1-misfit)*100 
quality    NUMERIC(2, 1)  YES  This attribute denotes the quality of an origin, an arrival, or a mechanism. 1.0 = good, 0.0 = bad 
pdc    NUMERIC(3, 0)  YES  Percent double couple of the seismic moment tensor 
pclvd    NUMERIC(3, 0)  YES  Percent compensated linear vector dipole of the seismic moment tensor 
piso    NUMERIC(3, 0)  YES  Percent isotropic of the seismic moment tensor. If the solution is constrained to have zero trace (no "ISO"), then "ISO" should be NULL, as opposed to a case where the full moment tensor was used, and the ISO component ended up being very small ("0") 
datetime    NUMERIC(25, 10)  NO  The date of associated with information in the record, in true epoch format 
rflag    VARCHAR(2)  YES  This flag describes whether an observation was generated automatically, by a human, or has been finalized 
lddate    DATE  YES  Load date. Date and time that the record was created, in Oracle date datatype 

mec Keys 
Key Name  Key Type  Keys 
meckey01  PrimaryKey  mecid 

mec Relationships 
Parent Relationships: 
Entity Name  Type  Cardinality  Business Name  VerbPhrase  InversePhrase  Foreign Keys  Is Supertype 
netmag  Non-Identifying  Zero or One to Zero or More        magid  NO 
origin  Non-Identifying  Zero or One to Zero or More        oridin  NO 
origin  Non-Identifying  Zero or One to Zero or More        oridout  NO 
remark  Non-Specific            NO 
Child Relationships: 
Entity Name  Type  Cardinality  Business Name  VerbPhrase  InversePhrase  Foreign Keys  Is Subtype 
mecobject  Non-Identifying  One To Zero or More          NO 
mecdata  Non-Identifying  One To Zero or More          NO 
eventprefmec  Non-Identifying  One To Zero or More          NO 
event  Non-Identifying  One To Zero or More          NO 
origin  Non-Identifying  One To Zero or More          NO 

mec Check Constraints 
Check Constraint Name  CheckConstraint 
mec13  plungen >= 0 and plungen <= 90 
mec14  plungep >= 0 and plungep <= 90 
mec15  plunget >= 0 and plunget <= 90 
mec16  pclvd >= 0 and pclvd <= 100 
mec17  pdc >= 0 and pdc <= 100 
mec18  piso >= 0 and piso <= 100 
mec19  pvr >= 0 and pvr <= 100 
mec20  rake1 >= -180 and rake1 <= 180 
mec21  rake2 >= -180 and rake2 <= 180 
mec23  srcduration >= 0.0 and srcduration <= 100.0 
mec24  striken >= 0 and striken <= 360 
mec25  strikep >= 0 and strikep <= 360 
mec26  striket >= 0 and striket <= 360 
mec27  strike1 >= 0 and strike1 <= 360 
mec28  strike2 >= 0 and strike2 <= 360 
mec29  tfd > 0 
mec30  undip1 >= -180 and undip1 <= 180 
mec31  undip2 >= -180 and undip2 <= 180 
mec38  unrake1 >= -180.0 and unrake1 <= 180.0 
mec39  unrake2 >= -180.0 and unrake2 <= 180.0 
mec40  unstrike1 >= -180.0 and unstrike1 <= 180.0 
mec41  unstrike2 >= -180.0 and unstrike2 <= 180.0 
mec01  dip1 >= -90 and dip1 <= 90 
mec02  dip2 >= -90 and dip2 <= 90 
mec03  erscalar >= 0.0 
mec05  mecid > 0 
mec06  mechtype in ('FP','MT') 
mec42  quality >= 0.0 and quality <= 1.0