Exécution de notre outil de synthèse sur un nouvel article
Vérifiez l’article ci-dessous, puis lancez sa synthèse.
The fractured Moon: Production and saturation of porosity in the lunar highlands from impact cratering
Jason M. Soderblom (Massachusetts Institute of Technology), Alexander Joseph Evans (Lamont-Doherty Earth Observatory, Columbia University), Brandon C. Johnson (Massachusetts Institute of Technology), H. J. Melosh (Purdue University West Lafayette), Katarina Miljković (Curtin University, Massachusetts Institute of Technology), Roger J. Phillips (Southwest Research Institute), J. C. Andrews‐Hanna (Colorado School of Mines), C. J. Bierson (University of California, Santa Cruz), James W. Head III (Brown University), C. Milbury (Purdue University West Lafayette), Gregory A. Neumann (Goddard Space Flight Center), F. Nimmo (University of California, Santa Cruz), David E. Smith (Massachusetts Institute of Technology), Sean C. Solomon (Lamont-Doherty Earth Observatory, Carnegie Institution for Science), Michael M. Sori (University of Arizona), Mark A. Wieczorek (Institut de physique du globe de Paris, Sorbonne Paris Cité), Maria T. Zuber (Massachusetts Institute of Technology)
Résumé : Abstract We have analyzed the Bouguer anomaly (BA) of ~1200 complex craters in the lunar highlands from Gravity Recovery and Interior Laboratory observations. The BA of these craters is generally negative, though positive BA values are observed, particularly for smaller craters. Crater BA values scale inversely with crater diameter, quantifying how larger impacts produce more extensive fracturing and dilatant bulking. The Bouguer anomaly of craters larger than km in diameter is independent of crater size, indicating that there is a limiting depth to impact‐generated porosity, presumably from pore collapse associated with either overburden pressure or viscous flow. Impact‐generated porosity of the bulk lunar crust is likely in a state of equilibrium for craters smaller than ~30 km in diameter, consistent with an ~8 km thick lunar megaregolith, whereas the gravity signature of larger craters is still preserved and provides new insight into the cratering record of even the oldest lunar surfaces.