PrirodaPrirodaПрирода0032-874XAkademizdatcenter Nauka62794510.7868/S0032874X20100026ArticlesСтатьиResearch ArticleRifts on Venus and Earth: Similarities and DifferencesРифты Венеры и Земли: сходство и различиеGusevaE. NГусеваЕ. Нguseva-evgeniya@yandex.ruIvanovM. AИвановМ. Аmikhail_ivanov@brown.eduИнститут геохимии и аналитической химии имени В.И.Вернадского РАН1512202010NO10 (2020)№10 (2020)112002032024Copyright ©; 2020, Издательство «Наука»2020Издательство «Наука»https://journals.eco-vector.com/0032-874X/article/view/627945

The terrestrial rift zones of the Eastern branch of the East African Rift System (EARS) have the greatest similarity with the Venusian rifts of Atla and BetaRegions where the dominant features are large dome-shaped rises. However, the rift-bearing domes of Venus are about two times larger than their terrestrial counterparts. The rift zones on Venus and Earth are similar in their linear axial grabens bounded by side uplifts; however their quantitative morphometric characteristics differ significantly. The rifts on Venus are about twice as long and wide comparing with the rifts of the Earth, although their horizontal extensions are significantly less. The mechanisms of rift origin appear to be similar for the Venusian Atla and Beta regions and for the Eastern branchof EARS. The impact of an ascending mantle flows onto the lithosphere, followed by formation of the domical rises and extension resulted in rift formation.The significant dissimilarities in their morphometric characteristics is most likely associated with the lithospheric thickness of the pre-rift lithosphere.

Наибольшее сходство с венерианскими рифтовыми областями Атла и Бета имеют земные рифты восточной ветви Восточно-Африканской рифтовой зоны. В обоих случаях доминирующие особенности рельефа — крупные сводовые поднятия. Однако рифтонесущие своды Венеры значительно крупнее своих земных аналогов. Рассматриваемые рифтовые зоны на нашей планете и на Венере выражены в рельефе схожими линейными осевыми грабенами, ограниченными бортовыми поднятиями, но их количественные морфометрические характеристики существенно различаются. Рифты Венеры приблизительно вдвое протяженнее и шире земных, а их горизонтальное растяжение значительно меньше. Механизмы рифтообразования, по-видимому, схожи для венерианских областей Атла и Бета и для восточной ветви Восточно-Африканской зоны Земли. Рифты сформированы в результате воздействия восходящего мантийного потока на литосферу с последующим сводообразованием и растяжением, а существенное различие их морфометрических характеристик, скорее всего, связано с разной мощностью дорифтовой литосферы.

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