Low crater frequencies and low model ages in lunar maria: Recent endogenic activity or degradation effects?

التفاصيل البيبلوغرافية
العنوان: Low crater frequencies and low model ages in lunar maria: Recent endogenic activity or degradation effects?
المؤلفون: Valantinas, A., Kinch, K. M., Bridžius, A.
سنة النشر: 2018
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Earth and Planetary Astrophysics
الوصف: Recently a number of studies have identified small lunar geologic structures to be <100 Ma in age using standard remote sensing techniques. Here we present new crater size frequency distributions (CSFD) and model ages using craters D> 10 m for 5 small target units: 1 Irregular Mare Patch (IMP) in Mare Nubium and 4 regions located on lunar wrinkle ridges in Mare Humorum. For comparison we also date another IMP found in a recent study in Mare Tranquillitatis (Braden et al., 2014). Absolute model age derivation corresponds to 46$\pm$5 Ma and 22$\pm$1 Ma for Nubium and Sosigenes IMP. We show that for IMPs and in nearby control mare regions similar production-like cumulative log-log SFD slopes of -3 are observed. In contrast control mare regions in Mare Humorum exhibit shallower equilibrium slopes from -1.83 to -2. 3 out of 4 wrinkle ridges appear to be in equilibrium but with crater life times lower than on the corresponding maria. Low crater frequencies on one wrinkle ridge result in an age of 8.6$\pm$1 Ma. This study region contains 80% fresh craters which suggests that the crater population is still in production indicative of a recent resurfacing event.
نوع الوثيقة: Working Paper
DOI: 10.1111/maps.13033
URL الوصول: http://arxiv.org/abs/1801.02575
رقم الأكسشن: edsarx.1801.02575
قاعدة البيانات: arXiv