Future lunar exploration will provide opportunities to expand the human scientific exploration of the Moon and, eventually, Mars. Planning for renewed field exploration of the Moon entails the selection, training, and capabilities of explorers; selection of landing sites; and adoption of an operational approach to extravehicular activity. Apollo program geological exploration, and subsequent analysis and interpretation of findings and collected samples underpin our current understanding of lunar origin and history. That understanding continues to provide new and important insights into the early histories of Earth and other bodies in the solar system, particularly during the period when life formed and began to evolve on Earth and possibly on Mars. Specific new lunar exploration objectives include: (1) testing the consensus “giant impact” hypothesis for the origin of the Moon; (2) testing the consensus impact “cataclysm” hypothesis; (3) determining the temporal flux of large impacts in the inner solar system; and (4) investigating the internal structure of the Moon. Apollo samples also identified significant and potentially commercial lunar resources that could help satisfy future demand for both terrestrial energy alternatives and space consumables. Equipment necessary for successful exploration includes that required for sampling, sample documentation and preservation, communications, mobility, and position knowledge. Easily used active geophysical, portable geochemical, and in situ petrographic equipment can greatly enhance the scientific and operational returns of extended exploration compared to that possible during the Apollo program.

Field geological research, as traditionally practiced on Earth, is an extremely flexible science. Although field geologists plan their traverses ahead of time—nowadays with the advantage of remote-sensing data—initial plans are continually modified in response to observations, such that traverses evolve over time. This research modality differs from that utilized in extreme environments on Earth (e.g., on the ocean floor), on the Martian surface by the mobile laboratories Spirit and Opportunity , and by the Apollo astronauts during their explorations of the Moon. Harsh and alien conditions, time constraints, and resource limitations have led to the development of operational modes that provide a constrained and usually lower science return than traditional field geology. However, emerging plans for renewed human exploration of the Moon, Mars, and near-Earth asteroids serve as an opportunity to invent a new paradigm for advanced planetary field geology that embraces coordinated human and robotic research activities. This approach will introduce an operational flexibility that is more like that of traditional field geology on Earth. In addition, human and robotic collaborations, combined with the integration of new “smart” tools, should provide an augmented reality that leads to even greater science return than traditional field geology. In order to take full advantage of these opportunities when planetary field geology again becomes practical, it is imperative for field geologists on Earth to begin right now to learn how best to incorporate advanced technologies into their research. Geologic studies of analog sites on Earth that employ new technology-enabled strategies rather than traditional research methods provide ideal opportunities to test and refine emerging designs for advanced planetary field geologic studies, as well as to gain new insights into terrestrial geologic processes. These operational experiments will be most informative if they embrace the entire geologic research process—including problem definition, field observation, and laboratory analysis—and not simply field work. The results of such comprehensive research can be used to inform the design of a maximally effective training regimen for future astronaut explorers.

Abstract Study of the distribution of the age-populations of detrital zircons in the Snake River system suggest that specific stream systems can be identified based on the detrital-zircon age-population signature (“barcode”) of ancient and Holocene sand deposits. Detrital zircon studies can be used on regional and local scales to determine changes in drainage patterns using both surface and subsurface data. Regional study of drainage patterns using detrital zircons found in Neogene strata of Idaho and southwest Montana suggest northeastward late Miocene to Holocene migration of the Continental Divide from the western side of the Pioneer Mountains to the current position in southwest Montana. Specifically, mixed populations of recycled Proterozoic detrital zircons that define the Wood River drainage are not found in the western Snake River Plain until after 7 Ma. Late Miocene eastward drainage from the central Snake River Plain to southwest Montana is suggested by 9–12 Ma detrital zircons found in fluvial strata less than 6 million years old, of the Sixmile Creek Formation Basalt eruptions of the Eastern Snake River Plain during the Pliocene and Pleistocene also caused drainage diversion. Detrital zircons in Pliocene sands from coreholes at Wendell and Mountain Home Air Force Base contain Big Lost River zircon provenance, suggesting that during the Pliocene, the Big Lost River flowed west along the central Snake River Plain. Late Pliocene and early Pleistocene basaltic volcanoes and rhyolite dome eruptions resulted in volcanic highlands, the Axial Volcanic Zone of the eastern Snake River Plain and the northwest-trending Arco Volcanic Rift Zone (which includes Craters of the Moon volcanic center). The development of these volcanic highlands disrupted the ancestral drainage of the Pliocene Big Lost River system, confining it to the Big Lost Trough, a volcanically dammed basin of internal drainage on the Idaho National Laboratory. After the Big Lost Trough was cut off from the main Snake River, basalt eruptions, local subsidence, and climate controlled the courses of the rivers that flowed into it. Detrital-zircon populations in core samples reveal the provenance of specific sand beds from the Big or Little Lost River systems.

The character and distribution of cooling ages in modern river sediment provide useful constraints on rates and patterns of uplift and erosion within actively deforming mountain ranges. Such sediment effectively samples all locations within the catchment area, irrespective of remoteness. We evaluate how successfully detrital cooling ages may be used to constrain hinterland erosion rates by examining the modern catchment of the Marsyandi River in central Nepal. Over the 100–200-km-length scale of the catchment, laser fusion 40 Ar/ 39 Ar data for detrital muscovite collected from 12 separate sites illustrate the downstream development of a detrital cooling-age signal that is both systematic and representative of the contributing area. Comparisons of paired samples indicate that, at short spatial (tens of meters) and temporal (hundreds of years) scales, the detrital cooling-age signal is consistent. The distribution of bedrock cooling ages in a subcatchment and the resulting detrital signal at the catchment mouth can be modeled as a function of the erosion rate, relief, hypsometry, catchment area, and muscovite distribution. Given that independent constraints are available for most of these variables, the detrital age signal should be a robust indication of the spatially averaged erosion rate. In the Marsyandi, our model predicts erosion rate differences of approximately twofold, with higher rates (>2 mm/yr) along the southern topographic front of the Himalaya.