3D geological models: A reliable depiction of nature or a sketch of our biases?

Authors: Zorzi, L; Elmo, D; Tafwidla, F; Lenauer, I; Furney, S

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DOI https://doi.org/10.36487/ACG_repo/2535_02

Cite As:
Zorzi, L, Elmo, D, Tafwidla, F, Lenauer, I & Furney, S 2025, '3D geological models: A reliable depiction of nature or a sketch of our biases?', in JJ Potter & J Wesseloo (eds), SSIM 2025: Fourth International Slope Stability in Mining Conference, Australian Centre for Geomechanics, Perth, https://doi.org/10.36487/ACG_repo/2535_02

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Abstract:
3D models represent the modelling team’s hypotheses about the most likely rock mass configuration, constructed from limited and sparse data (often as little as 1/100,000 or 0.00 1% of the rock mass). Therefore, modelling requires reliable professional judgement, which involves making decisions based on one’s beliefs about the information. This judgement is crucial for assessing the trustworthiness of data and interpolating between sample locations. Sound judgement adds value to the interpretation and modelling process. However, since judgement is influenced by personal opinions and beliefs, modellers must balance objectivity with subjective intuition, biases, and uncertainties. They must proactively prevent negative factors – such as guesses, gut feelings, and overconfidence – from entering the model, which still providing experience-based input to supplement the purely mathematical interpolation. Modellers and model users must recognise that a model is merely a sketch of a human interpretation about the rock mass, normally derived from sparse data points, whereas the rock mass itself is a product of natural processes and laws. While a model can be visually appealing or numerically sophisticated, it is unlikely to accurately depict nature's complexity. This work, based on open pit case studies, highlights the importance of explaining intuition, biases, and uncertainties when constructing geological, structural, or geotechnical models. It also discusses how to ensure these models are at least reliable hypotheses about the complex nature they aim to represent.

Keywords: 3D geological modelling, 3D structural model, uncertainties

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