Manual Picking (Horizon)

Insight includes intuitive manual picking tools to help you better define your horizon.

There are three methods of manual picking available:

Tip: Hotkeys are available to help speed up horizon picking. Click the Help icon at the top right of the Details Panel (also see Hotkeys).

Changes to horizons are stored in the Undo history. See (Undo/Redo horizon changes).

Manual picking configuration

Manually pick a horizon - straight line mode
  1. In the Horizon tab, select the horizon.
  2. Expand the Picking section.
  3. Choose a Picking Mode:
    • Straight Line
    • Amplitude Snapping
    • Propagator Guided
  4. Click the Manual Picking pencil icon. You can also click the pencil icon in the control panel horizon list to activate manual picking. 
  5. Replace existing picks: Check this box to replace horizon picks without erasing first. If unchecked, existing picks will remain in place.

Tip: When multiple horizons are listed, the pencil icon highlighted in the control panel is the horizon currently being picked.

Straight line mode

  1. In a section view or the 3D View.
  2. Select the line to interpret.
  3. Click on the section. The picker creates straight lines from one point to the next.

Amplitude snapping mode

Manually pick a horizon - amplitude snapping mode
  1. Select the Volume.
  2. Insight will snap to amplitudes from this volume
  3. Choose the Event Type to snap to:
    • Peak: The nearest positive peak
    • Trough: The nearest negative trough
    • Zero Inc: The nearest zero value (increasing from negative to positive)
    • Zero Dec: The nearest zero value (decreasing from positive to negative)

Note: A peak or trough is defined as having a greater magnitude than either neighbouring sample. The first or last sample of a range can never be a peak or trough.

  1. Snap Limit (ms): The maximum distance to search for the specified event

To use the amplitude snapping mode, click in the section on the horizon and roughly follow the event with the mouse. Insight will examine the data follow the event that matches the selected type.

Propagator guided mode

Manually pick a horizon - propagator guided mode
  1. Select the Volume. 
    • Insight will compare the waveform between traces in a window around the horizon and snap to the best matching amplitudes from this volume.
  2. Above, Below: 
    • The amount of each trace to compare. Defined in distance (or time) distance above and below the starting point.
    • Values are in-depth or time, depending on the horizon
  3. Symmetric window:
    • Use a symmetric window, with the same distance above and below
  4. Search (ms): The amount of vertical shift allowed from trace to trace
    • Use larger search values when picking steeply dipping horizons
    • Tip: Reducing the value can help prevent the propagator from moving to a different event or oscillating between two similar events.
  5. Threshold (%): How closely a propagated result must match the waveform to be included
  6. Snap (when enabled):
    • After finding the best point (by waveform), adjust the result to land exactly on the specified event
  7. Event: When snapping is enabled, use this event type
    • Peak: Nearest positive peak.
    • Trough: Nearest negative trough
    • Zero Inc: The nearest zero value (increasing from negative to positive)
    • Zero Dec: The nearest zero value (decreasing from positive to negative)
  8. Snap Limit: When snapping is enabled, the maximum distance to adjust the result

To use the propagator-guided mode, click on the section on the horizon and roughly follow the event with the mouse. Insight will examine the data following the event that matches the selected type. If it starts tracking the wrong event, move back and click on the last good point, then continue moving.

Tip: When using asymmetric windows with different above and below values, it can help to disable the snap function. Snapping often works against the propagation, miscorrecting the correct choices.

Note: When you hover over the horizon in a section view, the horizon name appears in the information bar at the base of the window to better identify the horizon.

Completing horizon picking

  1. Right-click or double-click to stop picking.
  2. Navigate to a new line or section:
    • Move the inline (up/down arrow keys) and/or crossline (left/right arrow keys) marker

Tip: Open a Map view window and select the horizon to evaluate your picking and compare to neighbouring lines. 

Exiting interpretation

Exit interpretation by pressing the Esc hotkey. Alternatively, you can turn off the active pencil icon in the control panel horizon list or the manual picking pencil icon.