POSC Specifications: Epicentre Version 3.0 | Relational Implementation |
A wavelet (W) or digital filter (F) are differentiated in terms of their effects on a physical process and to data representing it. In seismic, the physical process is a reflection series (R) and the data are the seismic trace values (T). The wavelet is defined by W*R = T and the digital filter by R = F*T, where * represents convolution. A filter is the inverse of a wavelet. Either a wavelet or a filter can be described in terms of both its frequency spectrum and time spectrum. A parametric description of a "notch" response will have a negative value for low cut rate and a positive value for high cut rate.
- instance_s (PK, M: CHAR VARYING(19))
- Surrogate key of the table.
- identifier (M: CHAR VARYING(80))
- wavelet_or_filter.identifier
A name which identifies the wavelet or filter.
- instance_create_date (O: TIMESTAMP)
- e_and_p_data.instance_create_date
This is the date that this instance was created. This date is defined by the source if imported, or is the date the instance is created if a new instance.
- last_updated (O: TIMESTAMP)
- e_and_p_data.last_updated
This is the date that this instance was last updated. This value should be updated when any part of this instance is altered (except for inverse relationships).
- r_wavelet_or_filter (FNK, M: CHAR VARYING(80))
- wavelet_or_filter.ref_wavelet_or_filter
Indicates a wavelet or a type of filter represented by the instance. Recognized values include wavelet, bandpass filter, lowpass filter, highpass filter, notch filter. Indicates whether the waveform described is the wavelet "in" the data or a filter applied "to" the data.
Defines a foreign key to table r_wavelet_or_filter.
- description (O: CHAR VARYING(2000))
- e_and_p_data.description
A remark or comment about the instance.
- dominant_period (O: FLOAT)
dominant_period_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.dominant_period
The dominant period of the wavelet.
dominant_period_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- dominant_wavelength (O: FLOAT)
dominant_wavelength_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.dominant_wavelength
The dominant wavelength of the wavelet.
dominant_wavelength_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- frequency_index_sl (O: CHAR VARYING(16))
- wavelet_or_filter.frequency_index
Defines the frequency axis associated with a frequency spectrum.
- frequency_spectrum_sl (O: CHAR VARYING(16))
- wavelet_or_filter.frequency_spectrum
The amplitude and-or phase values of the frequency spectrum for the wavelet or filter. The corresponding frequency values are defined by the frequency index.
- high_cut (O: FLOAT)
high_cut_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.high_cut
The frequency designator specific to a frequency where the response of the filter is attenuated 3 decibels (to 70% amplitude, or half power) of the total signal amplitude. Frequencies greater than the high cut are reduced by more than 3 decibels, and frequencies less than the high cut are reduced by less.
high_cut_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- high_cut_rate (O: FLOAT)
high_cut_rate_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.high_cut_rate
The rate, in decibels per octave, at which the amplitude spectrum changes with respect to increasing frequency at the high cut. Positive indicates a high cut (or top of a band pass) response. The power spectrum will change at twice this value.
high_cut_rate_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- impulse_response_sl (O: CHAR VARYING(16))
- wavelet_or_filter.impulse_response
The amplitude values of the time spectrum for the wavelet or filter. The time axis of the grid is defined by time index.
- instance_creator (O: CHAR VARYING(80))
- e_and_p_data.instance_creator
This is the person, company or application that created this instance. This identifies the party responsible for loading this instance.
- last_updated_by (O: CHAR VARYING(80))
- e_and_p_data.last_updated_by
This records the person or application making the update to this instance.
- low_cut (O: FLOAT)
low_cut_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.low_cut
The frequency designator specific to a frequency where the response of the amplitude filter is attenuated 3 decibels (to 70% amplitude or half power) of the total signal amplitude. Frequencies less than the low cut are reduced by more than 3 decibels, and frequencies greater than the low cut are reduced by less.
low_cut_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- low_cut_rate (O: FLOAT)
low_cut_rate_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.low_cut_rate
The rate, in decibels per octave, at which the amplitude spectrum of the wavelet/filter changes with respect to increasing frequency at the low cut. Positive indicates a low cut (or bottom of a band pass) response. The power spectrum changes at a value twice the low cut rate.
low_cut_rate_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- peak_amplitude (O: FLOAT(6))
- wavelet_or_filter.peak_amplitude
The peak amplitude in the frequency domain representation of the wavelet or filter.
- peak_frequency (O: FLOAT)
peak_frequency_u (FNK, O: CHAR VARYING(15))
- wavelet_or_filter.peak_frequency
The frequency at which the peak amplitude value occurs.
peak_frequency_u: Defines the unit of measure. Defines a foreign key to table r_unit_of_measure.
- source (O: CHAR VARYING(80))
- e_and_p_data.source
The provider of this instance, which is usually a data provider for imported/purchased data. If this instance is provided by POSC, then this attribute must be "POSC".
- time_index_sl (O: CHAR VARYING(16))
- wavelet_or_filter.time_index
Defines the time axis of the impulse response.
- activity_s (FSK, O: CHAR VARYING(19))
- process_data.activity
Defines the activity which created this instance.
Defines a foreign key to table activity.
- r_wavelet_filter_algorithm (FNK, O: CHAR VARYING(80))
- wavelet_or_filter.ref_wavelet_filter_algorithm
The algorithm for calculating the wavelet or filter. Examples are minimum phase wavelet, Ricker wavelet, Butterworth filter, etc.
Defines a foreign key to table r_wavelet_filter_algorithm.
Table is related to: data_collection_content, document_specification_part, geophysical_fcl_spectral_desc, @graphical_element, process_data_item
Primary Key Constraint on: INSTANCE_S
Generated on Tue Jul 10 17:11:14 2001
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