Introduction to this special section: Deep exploration

In the 1920s, the first oil discovery in Seminole, Oklahoma, was made at a depth of approximately 4000 ft using seismic reflection data. This breakthrough was achieved through the collaboration of Karcher's Geophysical Research Corporation and Amerada Petroleum Corporation. Today, J. Clarence Karcher's legacy lives on through SEG's prestigious annual award, presented to outstanding young geophysicists. Over the years, there has been a notable increase in the average depth of oil wells drilled. In 1949, the average depth was 3600 ft. By 2008, it was 6000 ft. As the consumption of oil and gas continues to grow globally, exploring deeper is a steady trend for hydrocarbon discovery. Currently the world's deepest oil well in Russia extends 49,000 ft into the earth's surface. Deep exploration below existing production, complex overburden, or at the limits of geophysical resolution is critical for existing and emerging ventures. To meet these challenges, researchers and geoscientists are actively working to acquire better data and develop innovative methods to improve imaging. Recent advances in hardware and equipment, data acquisition, algorithm development, computing, and digital technology allow for offshore and onshore exploration success and extended capability for exploration and production at higher efficiency in challenging deep environments. © 2023 by The Society of Exploration Geophysicists.