Characteristics and nature of gold-bearing fluids in Fatira
area, North Eastern Desert of Egypt: possible transition from
intrusion-related to orogenic deposits

J 2020

Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits

MONSEF, Mohamed Abd El; Marek SLOBODNÍK a Ibrahim A. SALEM

Základní údaje

Originální název

Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits

Autoři

MONSEF, Mohamed Abd El; Marek SLOBODNÍK a Ibrahim A. SALEM

Vydání

Arabian Journal of Geosciences, Heidelberg, Springer Heidelberg, 2020, 1866-7511

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10505 Geology

Stát vydavatele

Německo

Utajení

není předmětem státního či obchodního tajemství

Odkazy

URL

Impakt faktor

Impact factor: 1.827

Kód RIV

RIV/00216224:14310/20:00117218

Organizační jednotka

Přírodovědecká fakulta

DOI

https://doi.org/10.1007/s12517-020-05982-8

UT WoS

000576179900003

EID Scopus

2-s2.0-85091718982

Klíčová slova anglicky

Geochemistry; Microprobe; Chlorite geothermometry; Fluid inclusions; Orogenic gold; Granitic emplacement

Štítky

14315010, rivok

Příznaky

Mezinárodní význam, Recenzováno

Změněno: 4. 5. 2021 11:38, Mgr. Marie Novosadová Šípková, DiS.

Anotace

V originále

The gold lode in Fatira area is represented in three modes of occurrence: (1) altered felsite dykes, (2) massive quartz veins that are cutting through the hosting granitic rocks, and (3) siliceous-hybrid shear zone which is trending in NNW-SSE direction and separating between metavolcanic and granitic rocks. Metavolcanic rocks are described by meta-andesite and meta-dolerite varieties; they exhibit calc-alkaline magma type related to island arc system. However, granitic rocks are of I-type granodiorite composition with calc-alkaline affinity developed in convergent plate environment (island arc/active continental margins) during the late stage of orogeny. The wallrock alteration around the ore body includes propylitization, sericitization, and silicification facies. The ore minerals were observed as disseminated sulfides (pyrite, sphalerite, chalcopyrite, and covellite). Goethite, jarosite, and ilmenite are the main iron-rich mineral phase as well as malachite and rutile. Gold was detected by microprobe analysis within the internal composition of pyrite and/or jarosite. Two groups of fluid inclusions could be recognized in samples from different mineralized zones: (a) aqueous fluid inclusions (H2O-NaCl/KCl) and (b) aqueous-carbonic fluid inclusions (H2O-CO2-NaCl/KCl). Isochore construction from fluid inclusion data, combined with chlorite thermometry from alteration zone, revealed that Fatira gold deposits were formed at temperature range of 275-297 degrees C and pressure between 0.2 and 1.1 kb). The Fatira gold deposits exhibit similar features of both intrusion-related and orogenic deposits. Hence, the initial ore-bearing fluid was proposed to have originated from magmatic source at deeper levels related to the granitic emplacement (5-10 kb); moreover, the granitic batholith acted as an important vehicle for driving of the metamorphic hydrothermal currents and probably as a cause for the metamorphic process itself. Then, the migration of gold was taken place in form of bi-sulfide complexes and the final deposition occurred through fluid uplifting consequent with a possibility of mixing with meteoric water at shallow depths, pressure/temperature drop, and fluid/wallrock interactions.

Citovat

MONSEF, Mohamed Abd El; Marek SLOBODNÍK a Ibrahim A. SALEM. Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits. Arabian Journal of Geosciences. Heidelberg: Springer Heidelberg, 2020, roč. 13, č. 19, s. 1-24. ISSN 1866-7511. Dostupné z: https://doi.org/10.1007/s12517-020-05982-8.

@article{1703456,
   author = {Monsef, Mohamed Abd El and Slobodník, Marek and Salem, Ibrahim A.},
   article_location = {Heidelberg},
   article_number = {19},
   doi = {https://doi.org/10.1007/s12517-020-05982-8},
   keywords = {Geochemistry; Microprobe; Chlorite geothermometry; Fluid inclusions; Orogenic gold; Granitic emplacement},
   language = {eng},
   issn = {1866-7511},
   journal = {Arabian Journal of Geosciences},
   title = {Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits},
   url = {https://doi.org/10.1007/s12517-020-05982-8},
   volume = {13},
   year = {2020}
}

TY  - JOUR
ID  - 1703456
AU  - Monsef, Mohamed Abd El - Slobodník, Marek - Salem, Ibrahim A.
PY  - 2020
TI  - Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits
JF  - Arabian Journal of Geosciences
VL  - 13
IS  - 19
SP  - 1-24
EP  - 1-24
PB  - Springer Heidelberg
SN  - 18667511
KW  - Geochemistry
KW  - Microprobe
KW  - Chlorite geothermometry
KW  - Fluid inclusions
KW  - Orogenic gold
KW  - Granitic emplacement
UR  - https://doi.org/10.1007/s12517-020-05982-8
L2  - https://doi.org/10.1007/s12517-020-05982-8
N2  - The gold lode in Fatira area is represented in three modes of occurrence: (1) altered felsite dykes, (2) massive quartz veins that are cutting through the hosting granitic rocks, and (3) siliceous-hybrid shear zone which is trending in NNW-SSE direction and separating between metavolcanic and granitic rocks. Metavolcanic rocks are described by meta-andesite and meta-dolerite varieties; they exhibit calc-alkaline magma type related to island arc system. However, granitic rocks are of I-type granodiorite composition with calc-alkaline affinity developed in convergent plate environment (island arc/active continental margins) during the late stage of orogeny. The wallrock alteration around the ore body includes propylitization, sericitization, and silicification facies. The ore minerals were observed as disseminated sulfides (pyrite, sphalerite, chalcopyrite, and covellite). Goethite, jarosite, and ilmenite are the main iron-rich mineral phase as well as malachite and rutile. Gold was detected by microprobe analysis within the internal composition of pyrite and/or jarosite. Two groups of fluid inclusions could be recognized in samples from different mineralized zones: (a) aqueous fluid inclusions (H2O-NaCl/KCl) and (b) aqueous-carbonic fluid inclusions (H2O-CO2-NaCl/KCl). Isochore construction from fluid inclusion data, combined with chlorite thermometry from alteration zone, revealed that Fatira gold deposits were formed at temperature range of 275-297 degrees C and pressure between 0.2 and 1.1 kb). The Fatira gold deposits exhibit similar features of both intrusion-related and orogenic deposits. Hence, the initial ore-bearing fluid was proposed to have originated from magmatic source at deeper levels related to the granitic emplacement (5-10 kb); moreover, the granitic batholith acted as an important vehicle for driving of the metamorphic hydrothermal currents and probably as a cause for the metamorphic process itself. Then, the migration of gold was taken place in form of bi-sulfide complexes and the final deposition occurred through fluid uplifting consequent with a possibility of mixing with meteoric water at shallow depths, pressure/temperature drop, and fluid/wallrock interactions.
ER  -

MONSEF, Mohamed Abd El; Marek SLOBODNÍK a Ibrahim A. SALEM. Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits. \textit{Arabian Journal of Geosciences}. Heidelberg: Springer Heidelberg, 2020, roč.~13, č.~19, s.~1-24. ISSN~1866-7511. Dostupné z: https://doi.org/10.1007/s12517-020-05982-8.

Přehled o publikaci