Tectonometamorphic evolution and U–Pb dating of the high-grade Hammar Domain (Southern Ethiopian Shield), implications for the East-African Orogeny
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F21%3A00542869" target="_blank" >RIV/67985831:_____/21:00542869 - isvavai.cz</a>
Alternative codes found
RIV/00025798:_____/21:00000022 RIV/00216208:11310/21:10435360
Result on the web
<a href="https://www.sciencedirect.com/science/article/pii/S0301926821001984?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0301926821001984?via%3Dihub</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.precamres.2021.106270" target="_blank" >10.1016/j.precamres.2021.106270</a>
Alternative languages
Result language
angličtina
Original language name
Tectonometamorphic evolution and U–Pb dating of the high-grade Hammar Domain (Southern Ethiopian Shield), implications for the East-African Orogeny
Original language description
Based on new U–Pb zircon data, field structural analysis and a detailed petrological study of the plutonic and high-grade metamorphic rocks of the Hammar Domain (Southern Ethiopian Shield) overall geodynamic scenario was inferred, bringing broad implications for the East-African Orogeny. The structural evolution of the Hammar Domain can be summarized into four phases, D1 to D4, resulting in (a) relict compositional banding (S1), (b) flat-lying migmatite foliation (S2) defining the primary contacts of granulites and migmatites, (c) superimposed steeply dipping N–S trending compressional foliation (S3) due to regional ~E–W oriented compression and (d) later ~NW–SE trending left-lateral transpressive fabric (S4). New geochronological data point to long-lasting orogenic convergence forming the East-African Orogeny which resulted in two main geodynamic events: (a) Late Tonian to late Cryogenian episode (ca. 770 to 650 Ma) where large volcanic arc construction as the source of rock photoliths (dated at ca. 770 Ma) was followed by crustal accretion and flat-lying fabrics origin (D2 stage), intense migmatization and HT-MP metamorphism (T: 700–850 °C and P: 0.7–0.9 GPa) at depths of ~25–35 km (dated at ca. 720 and 715 Ma). (b) Late Cryogenian to early Ediacaran episode (ca. 650 to 620 Ma) as the key era of continental collision leading to the Greater Gondwana assembly. An early ~E–W oriented compression (D3 stage) resulted in ~N–S trending fabrics that have been continuously changed to the left-lateral transpression (D4 stage) forming ~NW–SE oriented foliations. The time-scale of D3 and D4 events is inferred by syn-tectonic granitoid intrusions yielded at ca. 648 Ma and ca. 630 Ma respectively. Furthermore, the syn- to post-tectonic leucogranite dike, dated at ca. 630 Ma, marks the upper limit for the ductile or brittle-ductile deformation and regional metamorphic events.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10505 - Geology
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2021
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Precambrian Research
ISSN
0301-9268
e-ISSN
1872-7433
Volume of the periodical
361
Issue of the periodical within the volume
August 2021
Country of publishing house
NL - THE KINGDOM OF THE NETHERLANDS
Number of pages
18
Pages from-to
106270
UT code for WoS article
000663340100021
EID of the result in the Scopus database
2-s2.0-85107146351