Research Status and Development Direction of Well Log Cyclostratigraphy

Well log cyclostratigraphy has become the foundation for studying many key scientific issues in the field of geosciences by identifying, extracting, and interpreting astronomical cycles recorded by geophysical logs. This paper analyzes the driving forces behind the development of well log cyclostratigraphy by systematically examining the research needs of cyclostratigraphy and the characteristics of geophysical logs. This paper assesses the current state in well log cyclostratigraphy by reviewing domestic and international research achievements in geophysical log proxies for paleoclimates, astronomical cycle analysis methods, and related areas. Based on the development trends in geosciences, this paper explores future directions for well log cyclostratigraphy. Although most geophysical logging techniques are initially developed for oil and gas exploration, their continuous, high-resolution, and multi-parameter measurement data have made them a crucial tool for studying orbitally forced paleoclimate. Currently, conventional logs, natural gamma-ray spectroscopy logs, and electrical imaging logs have been successfully used in cyclostratigraphy research. Progress has also been made in the response mechanisms of geophysical logs to orbital-scale climates, the identification methods of astronomical cycles in geophysical logs, and the evaluation methods for sensitivities of geophysical log proxies. In the future, the development of proxies based on imaging logging data, the establishment of joint analysis methods for multiple log proxies, and the application of intelligent processing and big data analytics will further unlock the potential of well log cyclostratigraphy in deep-time research, oil and gas exploration, and other fields.