Integrating automatic implicit geological modelling in geophysical inversion

Jeremie Giraud and Guillaume Caumon and Lachlan Grose and Paul Cupillard. ( 2022 )
in: 2022 {RING} {Meeting}, pages 33, ASGA

Abstract

We introduce and test methods to integrate automatic implicit geological modelling in the geophysical inversion process. The objective is to enforce structural geological realism in level-set inversion, which inverts for the location of interfaces between rock units. We propose two approaches. In the first one, a geological correction term is applied at each iteration of the inversion to reduce geological inconsistencies. This is achieved by integration of an automatic implicit geological modelling scheme within geophysical inversion. In the second approach, we use automatic geological modelling to derive a dynamic prior model term at each iteration of the inversion. This limits departures from geologically feasible outcomes. We introduce the main theoretical aspect of the proposed approaches and perform the proof-of-concept using two synthetic studies. The analysis of results using indicators measuring geophysical, petrophysical and geological misfits demonstrates that our approach effectively steers inversion towards geologically consistent models and reduces the risk of geologically unrealistic outcomes. Results suggest that geological correction may also be applied to pre-existing models to increase their geological realism and that it can also be used to explore geophysically equivalent models.

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BibTeX Reference

@inproceedings{giraud_integrating_2022,
 abstract = { We introduce and test methods to integrate automatic implicit geological modelling in the geophysical inversion process. The objective is to enforce structural geological realism in level-set inversion, which inverts for the location of interfaces between rock units. We propose two approaches. In the first one, a geological correction term is applied at each iteration of the inversion to reduce geological inconsistencies. This is achieved by integration of an automatic implicit geological modelling scheme within geophysical inversion. In the second approach, we use automatic geological modelling to derive a dynamic prior model term at each iteration of the inversion. This limits departures from geologically feasible outcomes. We introduce the main theoretical aspect of the proposed approaches and perform the proof-of-concept using two synthetic studies. The analysis of results using indicators measuring geophysical, petrophysical and geological misfits demonstrates that our approach effectively steers inversion towards geologically consistent models and reduces the risk of geologically unrealistic outcomes. Results suggest that geological correction may also be applied to pre-existing models to increase their geological realism and that it can also be used to explore geophysically equivalent models. },
 author = { Giraud, Jeremie AND Caumon, Guillaume AND Grose, Lachlan AND Cupillard, Paul },
 booktitle = { 2022 {RING} {Meeting} },
 pages = { 33 },
 publisher = { ASGA },
 title = { Integrating automatic implicit geological modelling in geophysical inversion },
 year = { 2022 }
}