EpiSeismic_SeismicDataset

Derived From:

EpEntity_Entity

Derivatives:

EpiSeismic_PostStack2d, EpiSeismic_PostStack3d

Capabilties:

read

Column Summary
Type	Name and Description
String ro	KeyString Unique identifier for each table entry.
PointSeq ro db	ActualExtent Very similar to the Extent column except this is the bounding box where seismic data exists in the dataset.
String ro db	Comment The comments associated with the seismic data set.
Float ro db	CompressionFactor Indicates if the seismic data is physically stored on disk in a compressed format.
Float ro req db	DeltaZ The Z axis sampling rate for the traces in the dataset.
String ro req db	DomainType Indicates if the seismic data is sampled in time or depth.
PointSeq ro db	Extent The seismic dataset's bounding box.
Float ro req db	MaxZ The maximum Z (time/depth) range for the trace data.
Float ro req db	MinZ The minimum Z (time/depth) range for the trace data.
String ro req db	Name The name of the seismic dataset.
ULong ro db	NumSamplesPerTrace The number of samples per trace in the data set.
ULong ro db	NumTraces The number of traces in the data set.
Boolean ro db	OwnedByProject Returns true if the seismic dataset is stored in the project identified by the Project Column.
String ro db	SampleDataType Identifies the default data type of how the seismic data will be returned to the client application.
String ro db	SampleKind A description of the seismic "bulk" data representation, such as "SEISMIC AMPLITUDE".
Float ro db	SampleMax The maximum amplitude of the seismic "bulk" data.
Float ro db	SampleMin The minimum amplitude of the seismic "bulk" data.
String ro db	SampleUnit The unit associated to the seismic "bulk" data.
Float ro db	SeismicElevationDatum The elevation datum giving meaning to time = zero for the SeismicDataset.
String ro db	SeismicElevationDatumUnit Unit associated with the SeismicElevationDatum.
String ro db	SeismicElevationReference The reference point for the seismic elevation datum.
String ro req db	StorageDataType Identifies the data type of how the seismic data is physically stored on disk.
String ro req db	UnitsZ Identifies the Z units for the MinZ, MaxZ, and DeltaZ columns.

 

Columns inherited from EpEntity_Entity

LastModifiedDate, Name, Project, ProjectName, StoreInstallationName, StoreType

 

Column Detail

KeyString

Unique identifier for each table entry.

StorageDataType

Identifies the data type of how the seismic data is physically stored on disk. This is important when making decisions for copying data to a new seismic dataset. The returned value can be different than getSampleDataType(). For example, some vendors support creating BYTE datasets but due to internal seismic scaling processing only support retrieving the data as FLOAT data.

Comment

The comments associated with the seismic data set.

DomainType

Indicates if the seismic data is sampled in time or depth.

SampleKind

A description of the seismic "bulk" data representation, such as "SEISMIC AMPLITUDE".

SeismicElevationDatum

The elevation datum giving meaning to time = zero for the SeismicDataset. This datum is used when displaying well data at the proper elevation with respect to the seismic data.

OwnedByProject

Returns true if the seismic dataset is stored in the project identified by the Project Column. Returns false if the seismic dataset is shared and owned by a different project.

SampleMax

The maximum amplitude of the seismic "bulk" data. This SampleMin and SampleMax values are useful for scaling the data when doing seismic visualization. In some cases, the value might not truly reflect the actual values stored on disk. Some vendor databases do not keep track of the actual min/max values and the only way to know the real min/max values is to read every trace and sample contained in the dataset which is not feasible. OpenSpirit does not read seismic data to determine the min/max values due to performance reasons. It is possible this column will be zero if the maximum cannot be determined without reading seismic data. If your application must know the true min/max values then you should use the getStatistics() method and specify your own samplingPercent for more accurate results.

SeismicElevationReference

The reference point for the seismic elevation datum. Some possible values are "Mean Sea Level", "Ocean Floor", etc.

ActualExtent

Very similar to the Extent column except this is the bounding box where seismic data exists in the dataset. Clients should always set the coordinate system when retrieving this column so they know the exact coordinate system the points are returned in; otherwise, the points will be returned in the default coordinate system and each vendor store might have a different default. It is possible the dataset was created with a large extent but the dataset hasn't been fully populated. This reflects the bounding box of existing traces. If the dataset is fully populated, the Extent and ActualExtent columns will return identical results. The ActualExtent and Extent will be identical if the vendor store doesn't have an easy way of identifying the actual extent without reading all the seismic traces. In other words, the ActualExtent is not guaranteed to be the minimum bounding box of the seismic data.

MaxZ

The maximum Z (time/depth) range for the trace data. The Z value is relative to the seismic reference datum, not the elevation datum (e.g. sea level), so the Z attribute will be positive. This maximum Z is the same for all traces in the dataset.

CompressionFactor

Indicates if the seismic data is physically stored on disk in a compressed format. The compression factor is a percentage (value between zero and one) that represents the amount of compression. A value of zero indicates no compression; a value of one indicates maximum compression.

NumTraces

The number of traces in the data set. For PostStack3d, it's (numInlines * numCrosslines), while the definition of a trace is independent of the volume's storage organization (i.e. TRACE, SLICE, BRICK). It is related to the how the seismic was acquired which is in the vertical orientation. For PostStack2d, it's the number of traces that have been written to the dataSet.

SampleDataType

Identifies the default data type of how the seismic data will be returned to the client application. This will be the data type of the returned samples if the seismic accessor is created without specifying a data type.

SampleUnit

The unit associated to the seismic "bulk" data. Seismic data is usually unitless but seismic velocity usually has a unit associated with it.

Name

The name of the seismic dataset..

UnitsZ

Identifies the Z units for the MinZ, MaxZ, and DeltaZ columns. This Z unit does not have to match the unit of the associated SeismicBinGridCS's third axis.

NumSamplesPerTrace

The number of samples per trace in the data set. The definition of a trace is independent of the volume's storage organization (i.e. TRACE, SLICE, BRICK). It is related to the how the seismic was acquired which is in the vertical orientation.

Extent

The seismic dataset's bounding box. Clients should always set the coordinate system when retrieving this column so they know the exact coordinate system the points are returned in; otherwise, the points will be returned in the default coordinate system and each vendor store might have a different default. The coordinate system has a big impact on the Z values. The Z values are unit converted to match the specified coordinate system's third axis. Must pass in a time-based coordinate system (third axis has a time Z unit) when the seismic dataset has a DomainType of TIME and a depth-based coordinate system when the DomainType is DEPTH so the Z unit can be successfully converted. The extent's Z range will not match the MinZ and MaxZ attributes if the specified coordinate system's third axis is not the same as UnitsZ (e.g. one could be milliseconds and the other seconds). All time-based coordinate systems have Z as the 2-way travel time relative to a seismic reference datum. The Z values are positive downward in these systems. For the SeismicBinGrid time and depth coordinate systems, the Z values are positive downward and are relative to the seismic datum. For the MapDepth coordinate system, the Z values are the elevation with respect to the projection system's geodetic datum. The Z values are negative downward below the datum. This is the maximum possible extent which the dataset is constrained (e.g. the dataset can not grow beyond this extent). Extent is returned in the form of an array of points (total 8) where first four points lie in minimum (start) time/depth plane and last four points lie in maximum (ending) time/depth plane. The points form a rectangular solid bounding box. The points are first and last inclusive (for example, if the volume was 1x1x1 then all eight points would be identical). For PostStack3d entities: The first point in the sequence identifies the volume's origin. All other points are in relation to this origin. The points are returned in the following order: (first Inline, first Crossline, minimum Z) - volume origin, (last Inline, first Crossline, minimum Z), (last Inline, last Crossline, minimum Z), (first Inline, last Crossline, minimum Z), (first Inline, first Crossline, maximum Z), (last Inline, first Crossline, maximum Z), (last Inline, last Crossline, maximum Z), (first Inline, last Crossline, maximum Z).

MinZ

The minimum Z (time/depth) range for the trace data. The Z value is relative to the seismic reference datum, not the elevation datum (e.g. sea level), so the Z attribute will be positive. This minimum Z is the same for all traces in the dataset.

SampleMin

The minimum amplitude of the seismic "bulk" data. This SampleMin and SampleMax values are useful for scaling the data when doing seismic visualization. In some cases, the value might not truly reflect the actual values stored on disk. Some vendor databases do not keep track of the actual min/max values and the only way to know the real min/max values is to read every trace and sample contained in the dataset which is not feasible. OpenSpirit does not read seismic data to determine the min/max values due to performance reasons. It is possible this column will be zero if the minimum cannot be determined without reading seismic data. If your application must know the true min/max values then you should use the getStatistics() method and specify your own samplingPercent for more accurate results.

DeltaZ

The Z axis sampling rate for the traces in the dataset.

SeismicElevationDatumUnit

Unit associated with the SeismicElevationDatum.