Numerous publications address the petrogenesis of the partially dolomitized Latemar carbonate platform, Italy. A common factor is interpretation of geochemical data in terms of heating via regional igneous activity that provided kinetically favorable conditions for replacement dolomitization. New field, petrographic, XRD, and geochemical data demonstrate a spatial, temporal, and geochemical link between replacement dolomite and local mafic igneous dikes that pervasively intrude the platform. Dikes are dominated by strongly altered plagioclase and clinopyroxene. Significantly, where ferroan dolomite is present, it borders dikes. We hypothesize that seawater interacted with mafic minerals, causing Fe enrichment in the fluid that subsequently participated in dolomitization. This hypothesis was tested numerically through thermodynamic (MELTS, Arxim-GEM) and reactive flow (Arxim-LMA) simulations. Results confirm that seawater becomes Fe-enriched during interaction with clinopyroxene (diopside-hedenbergite) and plagioclase (anorthite-albite-orthoclase) solid solutions. Reaction of modified seawater with limestone causes ferroan and nonferroan replacement dolomitization. Dolomite quantities are strongly influenced by temperature. At 40 to 80°C, ferroan dolomite proportions decrease with increasing temperature, indicating that Latemar dolomitization likely occurred at lower temperatures. This relationship between igneous dikes and dolomitization may have general significance due to the widespread association of carbonates with rifting-related igneous environments.
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2oXA3Xd
via IFTTT
Εγγραφή σε:
Σχόλια ανάρτησης (Atom)
Δημοφιλείς αναρτήσεις
-
Abstract Bromodomain proteins function as epigenetic readers that recognize acetylated histone tails to facilitate the transcription of t...
-
Abstract Purpose Overcoming the flaws of current data management conditions in head and neck oncology could enable integrated informatio...
-
1 abqls-210rm.html Read the latest Journal of Clinical Neurophysiology - Vol. 37, No. 1, January 2020.eml 2 agx3v-nxz96.html Read the late...
-
Ambergris Caye's best News Source. A weekly tourism and community oriented newspaper providing local news, stories, and reports on what...
-
by Yanwei Li, Haifeng Liu, Wei Zeng, Jing Wei An increase in the osmolarity of tears induced by excessive evaporation of the aqueous tear p...
-
http://ift.tt/2p41efZ
-
Abstract In present work, the electronic structure and optical properties of the FeX 2 (X = S, Se, Te) compounds have been evaluated by t...
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου