دورية أكاديمية

Upper Crustal Structure of Superfast‐Spread Oceanic Crust Exposed at the Pito Deep Rift: Implications for Seafloor Spreading

التفاصيل البيبلوغرافية
العنوان: Upper Crustal Structure of Superfast‐Spread Oceanic Crust Exposed at the Pito Deep Rift: Implications for Seafloor Spreading
المؤلفون: J. A. Karson, L. A. Chutas, N. W. Hayman, R. N. Hey, A. J. Horst, S. D. Hurst, E. M. Klein, D. F. Naar, R. J. Varga
المصدر: Geochemistry, Geophysics, Geosystems, Vol 24, Iss 3, Pp n/a-n/a (2023)
بيانات النشر: Wiley, 2023.
سنة النشر: 2023
المجموعة: LCC:Geophysics. Cosmic physics
LCC:Geology
مصطلحات موضوعية: seafloor spreading, oceanic crust, sheeted dikes, ophiolites, faulting, Geophysics. Cosmic physics, QC801-809, Geology, QE1-996.5
الوصف: Abstract A tectonic window into the upper 2,000 m of oceanic crust generated at the superfast spreading (∼142 mm/yr) southern East Pacific Rise exposes a continuous layered structure of basaltic lavas and sheeted dikes over gabbroic rocks. This relatively simple structure is in accord with expectations for crustal accretion at a very fast spreading rate and high magma budget where magmatic construction keeps pace with plate separation. Detailed observations show that basaltic lava flows dip progressively more steeply inward (toward the spreading axis where they were erupted). Underlying sheeted dikes are faulted and tectonically rotated to dip steeply outward. These structures are interpreted in terms of subsidence beneath the axis of the southern East Pacific Rise during crustal construction that allowed the lava unit to thicken to >400 m without creating comparable relief at the spreading center. Transitional units above and below the sheeted dike complex show that the thickness of upper crustal rock units is modified by tectonic and intrusive processes during accretion. The crustal structure shows that even approaching the superfast spreading end‐member of seafloor spreading, crustal accretion involves dramatic tectonic processes that are not obvious from the surface geology of spreading centers.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1525-2027
Relation: https://doaj.org/toc/1525-2027
DOI: 10.1029/2022GC010527
URL الوصول: https://doaj.org/article/8efd84fa3ff7496e9ad292f7422365e7
رقم الأكسشن: edsdoj.8efd84fa3ff7496e9ad292f7422365e7
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:15252027
DOI:10.1029/2022GC010527