Presentation for the January 2025 meeting:
Advancements in Pulsed Neutron Generator based Formation Evaluation while Drilling by Mathias Horstmann from SLB.
Abstract
Updates on the established pulsed-neutron-generator (PNG) based technology enable a new sourceless neutron-gamma density (sNGD) algorithm, improving measurement accuracy across various formation types and drilling environments. This algorithm, based on recent advances in nuclear modeling and downhole hardware capabilities, eliminates the need for radioactive sources, addressing challenges in handling, transportation, storage, and regulatory constraints. The integration of sourceless density measurement with other pulsed neutron generator such as the LWD high-resolution pulsed-neutron-induced gamma ray spectroscopy with an advanced lanthanum bromide (LaBr) detector and an artificial neural network-based mineralogy algorithm allows to determine mineral composition in real time. This technology effectively identifies and quantifies complex mineralogy during drilling, revealing discrepancies with subjective cuttings descriptions. Examples from complex Triassic formations of the NCS demonstrates that LWD spectroscopy accurately identifies varying degrees of dolomitization across several wells. The presentation is based on SPWLA manuscripts SPWLA-2024-0108, SPWLA-2024-0138 and SPWLA-2024-0141.
Bio
Mathias Horstmann is principal domain expert for petrophysics, geology and acoustics with SLB, supporting the offshore Atlantic region located in Stavanger, Norway. Mathias holds a MS in Geology from the EUCOR University of Freiburg, Germany and after working for a period in the mining industry, he joined SLB in 2002 as a field engineer in Europe and Africa. Mathias worked in management positions and held various petro-technical roles in formation evaluation and geosteering in Asia and Europe. Within Society of Petrophysicists and Well Log Analysts (SPWLA) he currently serves as the Regional Director for Europe and was the General Chairman of the 63rd annual symposium. Mathias is past president of the Norwegian Formation Evaluation Society (NFES) in which he held presidency between 2016-2023, he is also member of the European Association of Geoscientists and Engineers (EAGE) and also the Oberrheinischer Geologischer Verein (OGV).