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Monarch Magnetics

IFR1

Local crustal refinement for directional drilling.

Monarch IFR1 products add regional crustal-field information beyond the reference field, delivered as reusable vector corrections for a defined area of operation.

Discuss IFR1 coverage How IFR1 works

Why IFR1

Local crustal structure can matter at the scale of a drilling operation.

HDGM provides a high-resolution global reference field. IFR1 adds regional crustal information derived from magnetic survey data where still finer local detail is required.

The result is a vector correction model for the defined geographic area and depth range of operation.

Side-by-side magnetic declination maps over the Permian Basin comparing HDGM and IFR1 on a shared color scale, with IFR1 showing additional local crustal-field structure.
Permian Basin example. Magnetic declination across a 30 × 30 km region at 2.50 km MSL, epoch 2026.0, comparing HDGM and IFR1 on a shared color scale. HDGM provides the high-resolution global reference field; IFR1 incorporates local magnetic-survey information to resolve additional crustal-field structure. Data underlying the crustal-field modeling include U.S. Geological Survey (USGS) magnetic observations and broader international geomagnetic datasets.

Regional product

License the coverage you need and reuse it across wells.

Monarch IFR1 products are licensed for a defined geographic area rather than as a separate correction for each well. Within the licensed coverage, the same regional product can support repeated operations.

Coverage

Defined area and depth range

Coverage is matched to the area of operation and the vertical range required for the drilling program.

Output

Vector correction model

The product provides the regional magnetic correction needed to refine the reference field throughout the licensed volume.

Reference

Referenced to HDGM

Monarch IFR1 products are natively referenced to HDGM so the regional correction fits directly into the broader geomagnetic stack.

Data

Use the best available magnetic data

Depending on the region, production may use suitable public, licensed, or customer-provided magnetic survey data.

Validation

Independent checks are built into IFR1 production.

Monarch uses two independent modeling approaches. Agreement between the results provides a strong internal check on the product, while differences help inform modeling uncertainty. Where suitable independent observations are available, they provide an additional external validation.

Getting started

Start with the area of operation.

Monarch can evaluate the data availability, production requirements, and appropriate coverage before defining the final IFR1 product.

1

Geographic coverage

Provide the area of operation as a boundary, coordinates, or other suitable geographic definition.

2

Vertical range and intended use

Define the depth range and operational requirements the IFR1 product needs to support.

3

Available magnetic data

Share relevant survey data and metadata if available. Monarch can also evaluate appropriate public or licensed data sources.

The geomagnetic stack

IFR1 adds the local crustal refinement.

HDGM provides the reference field, IFR1 adds local crustal refinement, and IFR2 accounts for time-varying changes in the magnetic field.

HDGMReference field IFR1Local crustal refinement IFR2Time-varying correction
Uncertainty + validation across the stack

IFR1 coverage

Need local crustal refinement for an area of operation?

Contact Monarch with the area and depth range you need to cover. We can evaluate available data and discuss the appropriate IFR1 product.

Contact Monarch contact@monarchmag.com
Monarch Magnetics Boulder, Colorado, USA