First break picking¶

Detection of the earliest coherent seismic arrival time on each recorded trace for near-surface velocity and timing analysis.

Version: v1 · 2026-09-08 · History
Domain-specific #: 4545
Origin domain: exploration geophysics
Subdomain: exploration geophysics

Core Idea¶

Manual, statistical and machine-assisted pickers distinguish the first refracted or direct arrival from noise using amplitude, phase, correlation or multitrace coherence, with uncertainty propagated into inversion and static correction.^[1] A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence. The abstraction is therefore identified by a declared carrier, a transformation or constraint over that carrier, and an invariant that tells an analyst whether the named structure is genuinely present.

The load-bearing residual is not the broad topic of exploration geophysics. It is the domain-specific identity fixed by the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. That residual remains recognizable when examples, notation, scale, or implementation change, but it disappears if the carrier is mistyped, the condition that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit fails, a neighboring object is substituted, or notation and topical resemblance replace the constitutive test. This gives the entry an operational identity rather than merely a historical label.

A useful analysis keeps three layers separate. The constitutive layer says what must be true: the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. The evidential layer asks what observation or proof warrants the claim: type the carrier, state every parameter and convention in the definition, test that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases. The use layer asks what reasoning becomes available once the identity is established: recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions. Conflating the layers is the most common source of scope inflation.

Structural Signature¶

Carrier: the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets
Inputs or antecedent state: the exact exploration geophysics carrier, defining parameters and conventions, boundary conditions, source evidence, comparison cases, and any measurement or proof assumptions needed to evaluate First break picking
Constitutive operation: A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence.
Invariant: the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit
Recognition test: type the carrier, state every parameter and convention in the definition, test that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases
Output or consequence: recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions
Failure boundary: the carrier is mistyped, the condition that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit fails, a neighboring object is substituted, or notation and topical resemblance replace the constitutive test

What It Is Not¶

It is not the whole field of exploration geophysics. The field contains many questions and methods that do not instantiate First break picking.
It is not its most familiar example. A canonical instance directly demonstrates that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. exhibits the structure, but the example is evidence for the abstraction rather than its definition.
It is not the neighboring catalog concept Phase picking. Phase picking is the broader detection of seismic phase arrivals; first-break picking specifically chooses the earliest qualifying onset on each trace.
It is not a claim that every boundary case has one uncontested classification. a generalized or degenerate case may change existence, uniqueness, measurement, or naming conventions, so the exact definition of First break picking must control the decision
It is not an unrestricted metaphor for any process that seems similar. Outside exploration geophysics, the vocabulary and validity conditions do not transfer literally.

Scope of Application¶

First break picking belongs to exploration geophysics and is useful where the analyst can specify the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets, then evaluate the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. The scope is broad within that domain but bounded by the need for the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. Conceptual signal-analysis identity only; no seismic-source, explosive, high-voltage or field-acquisition operating procedure is provided.^[2]

Definition and recognition. Determine whether a proposed instance satisfies the constitutive conditions rather than merely sharing terminology.
Construction or evolution. Track how the exact exploration geophysics carrier, defining parameters and conventions, boundary conditions, source evidence, comparison cases, and any measurement or proof assumptions needed to evaluate First break picking are converted, constrained, or organized by A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence..
Comparison. Compare instances using carrier, parameters, convention, domain, scale, boundary conditions, evidence, exact versus approximate form, and limiting behavior, without treating convenience measures as the definition.
Boundary analysis. Diagnose cases where a generalized or degenerate case may change existence, uniqueness, measurement, or naming conventions, so the exact definition of First break picking must control the decision and state which convention or theorem controls the decision.
Downstream reasoning. Use the established identity to support recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions while preserving the assumptions under which the inference is valid.

Clarity¶

The abstraction clarifies a crowded vocabulary by making the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit the center of the account. A claim should name the carrier, the governing operation or relation, the applicable assumptions, and the recognition test. A bare label is insufficient because the name First break picking can be used for a formal identity, an implementation, or a neighboring result unless carrier and convention are stated. The disciplined statement is: given the exact exploration geophysics carrier, defining parameters and conventions, boundary conditions, source evidence, comparison cases, and any measurement or proof assumptions needed to evaluate First break picking, the structure counts as First break picking exactly when the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit.

This format also separates identity from measurement. Empirical, computational, or documentary proxies support recognition only under declared validity and uncertainty assumptions; formal cases require proof rather than measurement. Measurements can be noisy, implementations can approximate, and proofs can use equivalent characterizations; none of those facts licenses changing the object being measured. When reports disagree, first check scope and convention, then data or proof, and only then interpret the disagreement as substantive.

Manages Complexity¶

Without the abstraction, an analyst must reason directly over many local details: the carrier roles, admissibility assumptions, competing conventions, derived invariants, boundary cases, and proof or validation obligations specific to First break picking. First break picking compresses them into the roles in the structural signature. That compression permits comparison across instances without erasing the variables that determine validity. It also exposes which details may be varied safely and which are constitutive.

The compression has a price. A single label can hide canonical, generalized, restricted, approximate, computational, empirical, and historically variant formulations of First break picking. Good use therefore carries a small declaration of assumptions alongside the name. The abstraction manages complexity when it reduces the state space of the question while keeping the failure boundary visible; it mismanages complexity when the label substitutes for that boundary analysis.

Abstract Reasoning¶

Identify the carrier. State what the elements, states, objects, or observations are: the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets. Reject examples whose alleged carrier belongs to a different problem.
Lock the constitutive rule. Express the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit independently of one notation or implementation. This step prevents the canonical example from becoming the definition.
Derive consequences. From the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit, infer recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions. Record each assumption used so that a later change of setting does not silently preserve an invalid conclusion.
Test adversarial cases. Examine a generalized or degenerate case may change existence, uniqueness, measurement, or naming conventions, so the exact definition of First break picking must control the decision and an object that resembles First break picking in purpose or vocabulary but does not satisfy its invariant is outside the class. A robust identity explains why the first is convention-sensitive and why the second is outside the class.
Compare and refine. Use carrier, parameters, convention, domain, scale, boundary conditions, evidence, exact versus approximate form, and limiting behavior to compare legitimate instances, and refine the model when discrepancies reflect hidden variation rather than failure of the abstraction itself.

Knowledge Transfer¶

Knowledge transfers strongly among subfields of exploration geophysics because they reuse the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets, A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence., and type the carrier, state every parameter and convention in the definition, test that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases. A theorem, diagnostic, or modeling warning can travel when those roles remain literal. For example, the distinction between constitutive identity and a convenient observable transfers from A canonical instance directly demonstrates that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. to An applied instance preserves the same invariant under changed scale, notation, dataset, jurisdiction, or implementation..^[3]

Transfer outside the home domain is weaker. The skeletal pattern—type the carrier, apply the defining mechanism of First break picking, preserve its invariant, and derive only consequences licensed by the stated boundary—may suggest an analogy, but the domain-specific mechanisms, admissible evidence, and consequences do not come along automatically. The safe transfer procedure maps each role explicitly, checks the invariant again, and refuses the name when only a superficial resemblance remains.

Examples¶

Canonical¶

A canonical instance directly demonstrates that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit. The example exposes the carrier and directly tests that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit; changing incidental notation preserves the identity, while removing that condition destroys it. This example is canonical because every role can be inspected: the carrier is the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets; the operative rule is A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence.; the invariant is the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit; and the result supports recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions.^[1] Changing incidental notation or scale leaves the structure intact, while removing the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit destroys the classification.

Mapped back: the typed exploration geophysics carrier, including its objects, relations, parameters, conventions, evidence, boundary cases, and comparison targets → A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence. → the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit → recognizing and comparing instances of First break picking, deriving its domain-specific consequences, selecting valid models or methods, and preventing transfer beyond its assumptions

Applied / In Practice¶

An applied instance preserves the same invariant under changed scale, notation, dataset, jurisdiction, or implementation. The applied case qualifies only because the same invariant and boundary test remain literal under changed parameters or implementation. The applied case is not licensed merely by vocabulary. It qualifies because the same recognition test—type the carrier, state every parameter and convention in the definition, test that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit, compare the nearest accepted identity, and report counterexamples, uncertainty, and limiting cases—can be run and because the same failure boundary—the carrier is mistyped, the condition that the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit fails, a neighboring object is substituted, or notation and topical resemblance replace the constitutive test—remains meaningful.^[2] The case also shows why practical outputs should report assumptions, resolution, and uncertainty instead of a naked label.

Mapped back: declared instance → recognition test → boundary check → qualified use

Structural Tensions¶

T1: Axiomatic identity vs. operational recognition. The defining conditions may be exact while empirical or computational recognition is approximate. Neither pole can be removed without changing the analytical task. Diagnostic: Can the reviewer state both the exact condition and the evidence used to infer it?
T2: Local roles vs. global consequence. The mechanism is enacted through local relations, but the abstraction is usually valued for a global classification or prediction. Neither pole can be removed without changing the analytical task. Diagnostic: Does the claimed global result actually follow from the declared local conditions?
T3: Ideal form vs. finite representation. Theory states a clean invariant while data structures, measurements, or proofs expose only finite representations. Neither pole can be removed without changing the analytical task. Diagnostic: Would increasing resolution converge toward the same classification?
T4: Canonical convention vs. legitimate variants. A standard formulation supports communication, while variants may preserve the same core under changed assumptions. Neither pole can be removed without changing the analytical task. Diagnostic: Which role is invariant across variants, and which convention-specific conclusion changes?
T5: Compression vs. hidden assumptions. The name compresses a complex argument but can conceal prerequisites. Neither pole can be removed without changing the analytical task. Diagnostic: Can each downstream inference be traced to an explicit assumption?
T6: Autonomous residual vs. reduction to catalog neighbors. The candidate uses broader structures but adds an identity-bearing residual. Neither pole can be removed without changing the analytical task. Diagnostic: After subtracting the proposed parent and named neighbors, does the constitutive residual still support independent diagnostics?

Structural–Framed Character¶

The entry is structurally mixed but domain-framed. Its portable skeleton is type the carrier, apply the defining mechanism of First break picking, preserve its invariant, and derive only consequences licensed by the stated boundary. Its identity-bearing terms—First break picking, carrier, parameter, invariant, boundary, evidence, model, transformation, and application—derive their meaning from exploration geophysics and cannot be replaced by generic systems language without losing the tests that distinguish valid from invalid instances.

This mixed character explains why the abstraction is reusable inside the domain yet does not meet the Prime bar. The structure organizes reasoning, but its claims still depend on domain-specific objects, evidence, and intervention semantics.

Structural Core vs. Domain Accent¶

The structural core consists of a carrier, A trace is filtered or represented, an onset score is evaluated through time, spatial consistency across receivers constrains candidates and the earliest qualifying arrival is recorded with confidence., a recognition invariant, and a consequence. That skeleton may resemble patterns elsewhere, especially type the carrier, apply the defining mechanism of First break picking, preserve its invariant, and derive only consequences licensed by the stated boundary. The domain accent is not decorative: First break picking, carrier, parameter, invariant, boundary, evidence, model, transformation, and application determine what counts as an admissible carrier, a valid transition, and successful evidence.

The abstraction therefore remains domain-specific. A cross-domain reuse that preserves only words such as 'balance,' 'cut,' 'sequence,' 'loss,' or 'simulation' is metaphor. Literal transfer requires the original role structure and diagnostics, which in this case remain anchored in exploration geophysics.

The proposed strict upward parent is prime:threshold. prime:threshold is the nearest broader Prime; the source-domain carrier and recognition invariant supply the autonomous residual. This is a proposal-only workspace relationship: the accepted Prime supplies a genuinely instantiated structural prerequisite or superclass, while First break picking adds domain-specific constraints.

The entry does not collapse into that parent because the domain-specific identity fixed by the survey geometry and acquisition record, source time and receiver traces, preprocessing, target arrival type, onset feature or score, threshold and multitrace constraint, picked time, uncertainty and validation against interpreters or travel-time residuals are explicit It also declines a nearby thematic catalog node: the neighbor does not literally subsume the constitutive identity of First break picking. This explicit assert-and-decline pattern keeps the proposed DAG narrow and prevents a merely thematic edge.

The prospective workspace queue contains one strict upward edge to prime:threshold. No live DAG mutation is authorized.

Relationships to Other Abstractions¶

Current abstraction First break picking Domain-specific

Parents (1) — more general patterns this builds on

First break picking is a kind of Threshold Prime

The proposed strict upward parent is prime:threshold.

Hierarchy path (1) — routes to 1 parentless root

First break picking → Threshold

Neighborhood in Abstraction Space¶

First break picking sits in a crowded region of the domain-specific corpus (35^th percentile for distinctiveness): several abstractions share nearly its structure, so a description that fits it tends to fit its neighbors too.

Family — Seismology, Geophysics & Surveying (25 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-09-08

Not to Be Confused With¶

Phase picking. Phase picking is the broader detection of seismic phase arrivals; first-break picking specifically chooses the earliest qualifying onset on each trace.
One canonical example. An instance demonstrates the structure but does not define the whole abstraction.
Measurement or implementation of First break picking. A proxy or realization is evidence for the abstraction, not the abstraction itself.
Generalized First break picking. An extension qualifies only when its changed axioms and retained invariant are stated.

References¶

[1] Significance 'First-break picks' associated with the refracted arrival times are used in an inversion scheme to study the near-surface low-velocity zone and subsequent determination of static corrections. Static correction is a correction applied to geophysical data, especially seismic data, to compensate for the effect of near-surface irregularities, differences in the elevation of shots and geophones, or any application to correct the positions of source and receivers. History of First Break Picking Gelchinsky and Shtivelman (1983) used correlation properties of signals and applied a statistical criterion for the estimation of first arrivals time. Coppens (1985) calculated the ratio of energy of seismogram of the two windows and used that to differentiate in signal and noise. Michael D. McCormark et al. (1993) introduced a backpropagation neural network (BNN) method. The Neural network which edits seismic data or pick first breaks was trained by users, who were just selecting and presenting to the network examples of trace edits or refraction picks. The network then changes internal weights iteratively until it can reproduce the examples accurately provided by the users. Fabio Boschetti et al. (1996) introduce a fractal-based algorithm, which detects the presence of a signal by analyzing the variation in fractal dimension along the trace. This method works when signal-to-noise ratio is small, but it is considerably slow. A direct correlation method was introduced by Joseph et al. (1999) which was developed for use in highly time-resolved, low-noise signals acquired in the laboratory. In this method, the greatest value of Pearson's correlation coefficient between segments of observed waveforms near the pulse onset and at an appropriate reference serves as the time determination criterion. Zuolin Chen, et al. (2005) introduced a multi-window algorithm to detect the first break. In this method, three moving windows were used and the averages of absolute amplitudes in each window need to be calculated, then ratios based on the averages of the windows provide standards to differentiate signals from unwanted noise. Wong et al. (2009) introduced STA/LTA ratio method. This method is similar as Coppens' algorithm. The difference is to do the ratio of two averages of energy between a short-term window and a long-term window, which is denoted as STA/LTA (short-term average/long-term average), instead of calculating the ratio of energy of seismogram of the two windows in Coppens' algorithm. Methods of Automatic First Break Picking ===STA/LTA ratio Method=== Source: This method is similar as Coppens' (1985) algorithm. The difference is to do the ratio of two averages of energy between a short-term window and a long-term window, which is denoted as STA/LTA (short-term average/long-term average), instead of calculating the ratio of energy of seismogram of the two windows in Coppens' algorithm. The numerical derivative of the ratio can be defined as, : \begin{align} & d_i=r_{i+1}-r_i , i=1,2,...(n-1) \ \end{align} where r i+1 is the STA/LTA ratio at time index i+1, and r i is the STA/LTA ratio at time index i. For noise-free seismograms, the maximum value of the numerical derivative of the STA/LTA ratio is close to the time of the first arrival. Wong et al. (2009) modified the algorithm of the energy ratio method, where they named the method as modified energy ratio. In this method, they define the energy ratio as, : \begin{align} & er_i=\sum_{j=i}^{i+ne} x^{2_j/\sum_{j=i-ne}}i x^2_j \ \end{align} where x i is the times series representing a seismogram with the time index i=1, 2 ... N. and the number of points in an energy window is ne. Then, the modified energy ratio is defined as : \begin{align} & er3_i=(abs(x_i)^*er_i)3 \ \end{align} The peak of the modified energy ratio er3i is very closed to the time of first arrivals on noise-free seismograms. === Multi-Window Method=== Source: This method needs to calculate the averages of absolute amplitudes from a seismic trace by using three moving time windows before and after each time point (sample). When the instantaneous absolute amplitude exceeds an automatically adjusted threshold, ratios based on the averages of the windows over previous time samples provide standards to differentiate signals from unwanted noise. The multi-window automatic P phase picker operates in the time-domain. It includes procedures to define: time windows, standards, corresponding thresholds and waveform correction. 1. The averages of absolute amplitudes within BTA (Before Term Average), ATA (After Term Average) and DTA (Delayed Term Average) windows are respectively defined as follows: : \begin{align} &\overline{BTA(t)}=\sum_{i=1}^{m}\frac{|u(t-i)|}{m}\ &\overline{ATA(t)}=\sum_{i=1}^{n}\frac{|u(t+j)|}{n}\ &\overline{DTA(t)}=\sum_{j=1}^{q}\frac{|u(t+j+d)|}{q}\ &R_2(t)=\frac{\overline{ATA(t)}}{\overline{BTA(t)}}\ &R_3(t)=\frac{\overline{DTA(t)}}{\overline{BTA(t)}}\ \end{align} Standards R 2 (t) and R 3 (t) are used for the discrimination of high-amplitude short-duration and long-duration noise. 2.Thresholds is defined as : \begin{align} & H_1(t)=E_m(t-p)+\alpha E_{sd}(t-p) \ \end{align} where E m is mean and E sd is standard deviation; p is the number of shifted samples; α is the coefficient to adjust the height of the first threshold and is taken to be 3. From this equation it is obvious that H 1 (t) is automatically adjusted with the variance of the background noise. 3. H 1 (t) is defined larger than most pre-existing noise levels, and the instantaneous absolute amplitude at the trigger time point is higher than H 1 (t), according to the configuration of the first arrival of an event the real onset time must be earlier than the trigger time point. A waveform correction should be used to compensate this belated onset time. For an impulsive first arrival, the height of the absolute amplitude and the representative gradient at the trigger point can be used to accomplish the correction. Available Code Potash SU is a package including Seismic Unix style codes developed by Balazs Nemeth, it provides a subroutine called simple window-based first break picker, the figure shows the seismic images before and after the application of subroutine. thumb|Right one is before first break picking, left one is after first break picking Future Trend of the Topic Methods of Picking: automatic first-break picking has played an important role in seismic data processing, and directly influences the quality of seismic sections. Because of the increase of seismic survey size, more efficient and fast first break picking methods are needed, with parallel methods being preferred. Application of First Break detection: Traditionally the geophysicist uses first breaks for static correction. First break signal can also be used as observation data for history matching. == Notes ==. registry ↩a ↩b

[2] Coppens F., (1985). First arrival picking on common-offset trace collections for automatic estimation of static corrections. Geophysical Prospecting, 33, 1212-1231. registry ↩a ↩b

[3] Fabio Boschetti, Mike D. Dentith, and Ron D. List, (1996). A fractal-based algorithm for detecting first arrivals on seismic traces. Geophysics, Vol.61, No.4, P. 1095-1102. registry ↩