Laser cleaning of paleontological specimens from Rancho La Brea, California

For Russian citation (Opticheskii Zhurnal):

Morley S.L., Potze S., Парфенов В.А. Лазерная очистка предметов из палеонтологической коллекции музея Ла-Бреа // Оптический журнал. 2026. Т. 93. № 10. С. 86–96. http://doi.org/10.17586/1023-5086-2026-93-10-86-96

Morley S.L., Potze S., Parfenov V.A. Laser cleaning of paleontological specimens from Rancho La Brea, California [in Russian] // Opticheskii Zhurnal. 2026. V. 93. № 10. P. 86–96. http://doi.org/10.17586/1023-5086-2026-93-10-86-96

For citation (Journal of Optical Technology):

Abstract:

Subject of study. The use of laser processing for the pre-restoration preparation of objects from paleontological collections for display in museums. Aim of study. Investigation of the possibility of using laser cleaning technology to remove asphalt deposits from the surface of Late Pleistocene (55 kya – 10 kya) fossils. Scientific novelty. For the first time in the practice of one of the world’s largest paleontological centers, La Brea Tar Pits & Museum, experimental studies have been conducted comparing the effectiveness of laser treatment and traditional methods of cleaning fossils. Method. Experiments on laser cleaning of fossils were carried out using a pulsed Q-switched Nd:YAG laser generating radiation at a fundamental wavelength of 1064 nm and a second harmonic wavelength of 532 nm. Dry and wet laser cleaning was used. A Canon EOS 5 digital camera and an optical stereo microscope with 7x – 45x magnification were used to evaluate the effectiveness and safety of laser processing. Main results. Based on experimental data, it has been established that an Nd:YAG laser with a wavelength of 532 nm and an energy density in the range of 0.5...1 J/cm2 makes it possible to effectively and safely remove asphalt deposits from the surface of fossils containing chitin and plant remains. Laser cleaning is more effective than mechanical and chemical methods. Practical significance. The results obtained can be used in carrying out practical restoration works to prepare objects from paleontological collections for display.

Keywords:

laser cleaning, Nd:YAG laser, paleontological collections, The La Brea Tar Pits & Museum, fossils, asphalt matrix, restoration, Cultural Heritage

OCIS codes: 350.3390; 140.3460

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