کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8907662 1635126 2018 29 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Biostratigraphy and petrography of upper Paleozoic rocks of Sierra Las Pintas, northern Baja California
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
پیش نمایش صفحه اول مقاله
Biostratigraphy and petrography of upper Paleozoic rocks of Sierra Las Pintas, northern Baja California
چکیده انگلیسی
A transported crinoid fauna is herein described for the first time in the Paleozoic succession cropping out in the Sierra Las Pintas, northern Baja California, northwestern Mexico. The fossil association includes Heterostelechus texanus Moore and Jeffords, Preptopremnum laeve? Moore and Jeffords, and Mooreanteris perforatus Moore and Jeffords, which indicates a Middle Pennsylvanian-early Permian time-averaged age. The studied area corresponds with the northernmost outcrop of definitely late Paleozoic deep-water facies in northwestern Mexico and the southern United States. Petrographic analyses indicate that the studied metasandstones were primarily derived from high-grade metamorphic rocks and from a shallow-water platform environment dominated by crinoid meadows. These results allow the correlation of the studied metasedimentary rocks with the Carboniferous Rancho Nuevo Formation of the Sonora allochthon, which crops out in central Sonora. The Sonora allochthon includes an Early Ordovician-Late Pennsylvanian sedimentary succession that was deposited in the oceanic basin located south of the Laurentian craton. Therefore, upper Paleozoic metasedimentary rocks of the Sierra Las Pintas were deposited along the same continental margin of Laurentia as those rocks in the Sonora allochthon, and were mostly derived from metamorphic rocks of the continental craton and by the typical Carboniferous encrinites, which characterize the shallow-water rocks of central and northern Sonora.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of South American Earth Sciences - Volume 84, July 2018, Pages 160-171
نویسندگان
, , , ,