Arc volcanism and rifting

Rifting, lithosphere breakup and volcanism: Comparison of magma-poor and volcanic rifted margins

On rates and styles of late volcanism and rifting on Venus

[1] We investigated the possibility of significant variations in the rates and styles of volcanism and rifting during the time postdating the formation of regional plains on Venus. We analyzed the age relations of all known impact craters 30 km in diameter (183 craters) with the neighboring geologic units. Of these we selected 164 craters which were superposed on regional plains and determined ...

Beta Regio, Venus: Evidence for uplift, rifting, and volcanism due to a mantle plume

Geophysical data have led to the interpretation that Beta Regio, a 2000×25000 km wide topographic rise with associated rifting and volcanism, formed due to the rise of a hot mantle diapir interpreted to be caused by a mantle plume. We have tested this hypothesis through detailed geologic mapping of the V-17 quadrangle, which includes a significant part of the Beta Regio rise, and reconnaissance...

Early stages in the evolution of Izu–Bonin arc volcanism: New age, chemical, and isotopic constraints

A remarkable record of early arc volcanism in the Izu–Bonin–Mariana (IBM) arc is exposed in and around the Bonin Islands, an uplifted segment of the IBM forearc. New Ar/Ar dating results imply that the boninitic volcanism on Chichijima Island occurred in a brief period during Eocene time, between 46–48 Ma. A slightly younger volcanic succession is identified along the Bonin Ridge, including 44....

New Zealand: dating the transition between volcanism in the Coromandel Arc and the Taupo Volcanic Zone

Subduction-related volcanism in the northern part of the North Island of New Zealand shifted abruptly during the late Pliocene. This study focuses on the transition, in time and space, from the NNW-oriented Miocene–Pliocene Coromandel Volcanic Zone to the northeast-oriented active Taupo Volcanic Zone. The volcanic rocks marking this transition are exposed in the Tauranga Basin and adjacent Kaim...