Age relationships of the Rembrandt basin and Enterprise Rupes, Mercury

Abstract

The Rembrandt basin is the largest well-preserved impact feature in the southern hemisphere of Mercury. Its smooth volcanic infill hosts wrinkle ridges and graben, and the entire basin is cross-cut by the Enterprise Rupes scarp system. On the basis of the Model Production Function crater chronology, our analysis shows that the formation of the Rembrandt basin occurred at 3.8±0.1 Ga during the Late Heavy Bombardment, consistent with previous studies. We also find that the smooth plains interior to the basin were emplaced between 3.7 and 3.6±0.1 Ga, indicative of a resurfacing event within the Rembrandt basin that is consistent with the presence of partially buried craters. These youngest plains appear temporally unrelated to basin formation, and so we regard their origin as likely to be due to volcanism.We identify the same chronological relationship for the terrain cross-cut by Enterprise Rupes to the west of the basin. Therefore, volcanic activity affected both the basin and its surroundings, but ended prior to the majority of basin and regional-scale tectonic deformation. If Enterprise Rupes formed prior to the Rembrandt basin, then regional-scale tectonic activity along this structure might have lasted at least 200 myr

Widespread effusive volcanism on Mercury likely ended by about 3.5 Ga

“…The N (10) values we report here for these nine sites are similar to those for the largest expanses of effusive volcanic deposits on Mercury—the NSP, Caloris Planitia and the smooth plains exterior to Caloris, and the Rembrandt interior plains [ Fassett et al ., ; Head et al ., ; Strom et al ., ; Denevi et al ., ; Ferrari et al ., ; Ostrach et al ., ]—as well as for smaller units, including smooth plains near Rudaki crater [ Denevi et al ., ] (Tables and S1). Further, our results for the Beethoven and Faulkner sites resemble N (10) values for those deposits reported earlier [e.g., Denevi et al ., ; Whitten et al ., ].…”

“…In the southern hemisphere, the plains interior to the Rembrandt basin form the largest volcanic deposit. Crater size–frequency analyses have shown that the NSP and the Caloris and Rembrandt interior plains were emplaced at around 3.7 Ga [ Fassett et al ., ; Head et al ., ; Strom et al ., ; Denevi et al ., ; Ferrari et al ., ; Ostrach et al ., ] for many of the published chronology models for Mercury [e.g., Marchi et al ., ], including the model of Le Feuvre and Wieczorek [] that incorporates the effects of a porous megaregolith. Further, the areal density of impact craters for an additional large smooth plains deposit on Mercury—southeast of the Rachmaninoff basin, near Faulkner crater—is comparable to those for the NSP and the Caloris interior plains [ Fassett et al ., ; Denevi et al ., ; Whitten et al ., ; Ostrach et al ., ], implying that this additional unit is similar in age.…”

Fault‐bound valley associated with the Rembrandt basin on Mercury

“…Smooth plains in the interior of Rembrandt, mapped on the basis of morphology and spectral characteristics, are interpreted to be volcanic in origin and are the oldest expanse of smooth plains on Mercury with an N (20) value of 45 ± 12 [ Denevi et al , ]. Ferrari et al [] estimated ages for Rembrandt (~3.8 Ga) and the interior smooth plains (~3.6 Ga) using a model production function method, comparable to previous estimates [ Watters et al , ; Fassett et al , ; Denevi et al , ].…”

“…Ferrari et al [] speculated that the formation of Enterprise Rupes predates the formation of the Rembrandt basin. They suggested that postscarp formation of the basin perturbed the stress field and reoriented the strike of a branch of the fault as it grew within the new basin.…”

Volcanism and tectonism across the inner solar system: an overview

“…The time-stratigraphic relationship between the 715 km-diameter Rembrandt impact basin and the Enterprise Rupes scarp system, which extends for over 800 km across the surface of Mercury, is the focus of the work by Ferrari et al (2014). These authors find that the Rembrandt basin formed at about 3.8 Ga, with resurfacing of its interior by volcanic smooth plains occurring within 100 -300 myr after basin formation.…”