Fracture Orientation

This document details Datarock’s product Fracture Orientation.

Widespread orientation measurement of fractures offers several significant benefits across the mining value chain, ranging from geological understanding to geotechnical assessments and mining efficiency.

Contents

Dependent Models

The outputs of the following models are used:

Model Name

Model Type

Fracture Detection and Classification

Object Detection

Drillers Break

Object Detection

Fracture Mask

Instance Segmentation

Orientation Line Tick

Object Detection

Data Processing

The following steps are taken to determine the orientation of a given fracture. This process is completed on every fracture we can measure.

  1. Take the output of the fracture detection model, “simple” classes only

  2. Run a segmentation model to extract the fracture profile

  3. image-20240118-003108.png

    Prediction of the orientation line proceed with detection of the orientation tick marks on the core.

  4. image-20240118-004019.png

    Combine the fracture profiles and the orientation line ticks

  5. Fit ellipses to the left, middle and right of the fracture interface, undertake QA to determine which measurements are suitable.

  6. Using survey file, determine the dip and dip direction of the fracture.

Product Configuration Options

Configuration

Options

Configuration

Options

Location of ori line as marked by the orientation tool

Bottom (default) or top of core

Positive dip direction as measured by the survey tool

Down (default) or up

User Data

Downhole survey data must be provided in the following format format:

  • HoleID_survey.csv

CSV file to contain the following headers:

File Header

Description

hole_id

Hole Name

depth

The vertical distance from the surface down to the bottom of the drilled hole

azimuth

Azimuth is the horizontal orientation of the drill path, measured in degrees from true north (or grid north).

dip

Dip refers to the angle at which the drill hole deviates vertically from the horizontal plane, measured in degrees.

Data Output

Results from this product is delivered in a batch nature.

Integration of the required technologies into Datarock production is ongoing.

The available CSV files include the following:

  • ProjectID_fracture_orientation.csv

This output includes a list of every detected fracture in the hole, with orientation measurements included, or reason for not successfully measuring.

File Header

Description

hole_id

Customer’s Hole ID

depth_m

Depth of fracture downhole (metres)

depth_ft*

Depth of fracture downhole (feet)

depth_from_m

Depth of the beginning of the fracture detection bounding box (metres)

depth_to_m

Depth of the end of the fracture detection bounding box (metres)

depth_from_ft*

Depth of the beginning of the fracture detection bounding box (feet)

depth_to_ft*

Depth of the end of the fracture detection bounding box (feet)

class_reduced

Fracture type (based on fracture detection model)

shape_status

Fracture overlay success or failure (with reason)

ori_status

Orientation line detection success or failure with respect to specific fracture

selected_skeleton

The selected side of the fracture to reporting orientation measurements

ori_azimuth

Fracture azimuth angle

ori_dip

Fracture dip angle

ori_error

Error of the ellipse fitting step to the selected side of the fracture

ori_tick_count

Orientation tick marks associated with the ori line detection for that fracture

*Only included if project depths are in feet.

Product Limitations

Limitations

Comments

Image Quality and Resolution

Like all Datarock products, the accuracy of fracture orientation measurements rely on well presented and photographed drill core.

Poor core markup and curation, as well as poor quality imaging can limit the quality of the outputs.

Core Surface Conditions

Drilled cores can have irregular surfaces, cracks, or fragmented areas. These conditions can obscure or mimic tick marks, leading to false detections or missed fracture measurements.

Orientation Tick Mark Clarity

Orientation line tick marks made during the core markup process may not always be clear or consistent. If the tick marks are faint, worn off or partially damaged, the models model may be limited in their ability to detect them.

Overlap with Other Markings

Other types of markings on the core, such as geological annotations and cut lines, can be mistaken for orientation lines if not clearly differentiated. We recommend following Datarock’s Core Photography Guidelines for best practice (contact us for details)

Fractures parallel to core axis

Fractures that are parallel to the core axis are generally not measured due to the way they are normally presented within the image.

Difference between Datarock and logged data

Datarock will measure and provide data for every measurable fracture, whereas manually logged data will include selected measurements only.

Document Version

Version

Date

Author

Rationale

1

10 Jan 2024

L Yanez

Initial release

2

29 Jan 2024

S Johnson

Updated to include depth in feet