Genesis of the Urals VHMS deposits inferred from coupled Pb-Os isotope systematics

Svetlana G. Tessalina; Jean Jacques Orgeval

Genesis of the Urals VHMS deposits inferred from coupled Pb-Os isotope systematics

Svetlana G. Tessalina^*, Jean Jacques Orgeval

^*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceeding › Conference proceeding contribution › peer-review

Abstract

Coupled Pb-Os isotope systematics were studied within ore facies, host rocks and sediments from the Paleozoic VHMS deposits in Southern Urals, Russia.

Lead isotope composition becomes progressively more radiogenic from early fore-arc environments to intra-arc and back-arc settings, which can be explained in terms of metasomatism of the depleted mantle wedge in the Ordovician - Early Devonian due to subduction of sediments and continental fragments. A metasomatized mantle wedge signature is expressed in LREE enrichment and low epsilon(Nd) values.

Os and other PGEs are enriched in first-stage high-temperature portions of hydrothermal systems, whereas Re has more affinity with lower temperature polymetallic assemblages. In each deposit, the Re/Os ratio and initial (187)OS/(188)Os isotopic compositions in ores decrease from the bottom to the top of hydrothermal system, reflecting variable degrees of mixing between hydrothermal fluid and Devonian seawater.

The Re-Os model ages for four studied deposits from different tectonic settings are similar (about 366 +/- 5 Ma) and younger than the presumed stratigraphic ages. This age could indicate a late Os isotope reequilibration associated with long living hydrothermal processes attending formation and closure of the Urals paleo-ocean in a Late Devonian time.

Original language	English
Title of host publication	Smart science for exploration and mining
Editors	PJ Williams
Place of Publication	Townsville, QLD
Publisher	JAMES COOK UNIV
Pages	263-265
Number of pages	3
ISBN (Print)	9780980558685
Publication status	Published - 2010
Event	10th Biennial SGA Meeting of the Society for Geology Applied to Mineral Deposits - Townsville, Australia Duration: 17 Aug 2009 → 20 Aug 2009

Conference

Conference	10th Biennial SGA Meeting of the Society for Geology Applied to Mineral Deposits
Country/Territory	Australia
City	Townsville
Period	17/08/09 → 20/08/09

Keywords

Massive sulphide deposits
Urals
isotope systematics
Pb
Os
MASSIVE SULFIDE DEPOSITS
SOUTH URALS
CONSTRAINTS
OROGEN

Cite this

@inproceedings{5b6e58986e464592a02d47f84d2648d6,

title = "Genesis of the Urals VHMS deposits inferred from coupled Pb-Os isotope systematics",

abstract = "Coupled Pb-Os isotope systematics were studied within ore facies, host rocks and sediments from the Paleozoic VHMS deposits in Southern Urals, Russia.Lead isotope composition becomes progressively more radiogenic from early fore-arc environments to intra-arc and back-arc settings, which can be explained in terms of metasomatism of the depleted mantle wedge in the Ordovician - Early Devonian due to subduction of sediments and continental fragments. A metasomatized mantle wedge signature is expressed in LREE enrichment and low epsilon(Nd) values.Os and other PGEs are enriched in first-stage high-temperature portions of hydrothermal systems, whereas Re has more affinity with lower temperature polymetallic assemblages. In each deposit, the Re/Os ratio and initial (187)OS/(188)Os isotopic compositions in ores decrease from the bottom to the top of hydrothermal system, reflecting variable degrees of mixing between hydrothermal fluid and Devonian seawater.The Re-Os model ages for four studied deposits from different tectonic settings are similar (about 366 +/- 5 Ma) and younger than the presumed stratigraphic ages. This age could indicate a late Os isotope reequilibration associated with long living hydrothermal processes attending formation and closure of the Urals paleo-ocean in a Late Devonian time.",

keywords = "Massive sulphide deposits, Urals, isotope systematics, Pb, Os, MASSIVE SULFIDE DEPOSITS, SOUTH URALS, CONSTRAINTS, OROGEN",

author = "Tessalina, {Svetlana G.} and Orgeval, {Jean Jacques}",

year = "2010",

language = "English",

isbn = "9780980558685",

pages = "263--265",

editor = "PJ Williams",

booktitle = "Smart science for exploration and mining",

publisher = "JAMES COOK UNIV",

note = "10th Biennial SGA Meeting of the Society for Geology Applied to Mineral Deposits ; Conference date: 17-08-2009 Through 20-08-2009",

}

TY - GEN

T1 - Genesis of the Urals VHMS deposits inferred from coupled Pb-Os isotope systematics

AU - Tessalina, Svetlana G.

AU - Orgeval, Jean Jacques

PY - 2010

Y1 - 2010

N2 - Coupled Pb-Os isotope systematics were studied within ore facies, host rocks and sediments from the Paleozoic VHMS deposits in Southern Urals, Russia.Lead isotope composition becomes progressively more radiogenic from early fore-arc environments to intra-arc and back-arc settings, which can be explained in terms of metasomatism of the depleted mantle wedge in the Ordovician - Early Devonian due to subduction of sediments and continental fragments. A metasomatized mantle wedge signature is expressed in LREE enrichment and low epsilon(Nd) values.Os and other PGEs are enriched in first-stage high-temperature portions of hydrothermal systems, whereas Re has more affinity with lower temperature polymetallic assemblages. In each deposit, the Re/Os ratio and initial (187)OS/(188)Os isotopic compositions in ores decrease from the bottom to the top of hydrothermal system, reflecting variable degrees of mixing between hydrothermal fluid and Devonian seawater.The Re-Os model ages for four studied deposits from different tectonic settings are similar (about 366 +/- 5 Ma) and younger than the presumed stratigraphic ages. This age could indicate a late Os isotope reequilibration associated with long living hydrothermal processes attending formation and closure of the Urals paleo-ocean in a Late Devonian time.

AB - Coupled Pb-Os isotope systematics were studied within ore facies, host rocks and sediments from the Paleozoic VHMS deposits in Southern Urals, Russia.Lead isotope composition becomes progressively more radiogenic from early fore-arc environments to intra-arc and back-arc settings, which can be explained in terms of metasomatism of the depleted mantle wedge in the Ordovician - Early Devonian due to subduction of sediments and continental fragments. A metasomatized mantle wedge signature is expressed in LREE enrichment and low epsilon(Nd) values.Os and other PGEs are enriched in first-stage high-temperature portions of hydrothermal systems, whereas Re has more affinity with lower temperature polymetallic assemblages. In each deposit, the Re/Os ratio and initial (187)OS/(188)Os isotopic compositions in ores decrease from the bottom to the top of hydrothermal system, reflecting variable degrees of mixing between hydrothermal fluid and Devonian seawater.The Re-Os model ages for four studied deposits from different tectonic settings are similar (about 366 +/- 5 Ma) and younger than the presumed stratigraphic ages. This age could indicate a late Os isotope reequilibration associated with long living hydrothermal processes attending formation and closure of the Urals paleo-ocean in a Late Devonian time.

KW - Massive sulphide deposits

KW - Urals

KW - isotope systematics

KW - Pb

KW - Os

KW - MASSIVE SULFIDE DEPOSITS

KW - SOUTH URALS

KW - CONSTRAINTS

KW - OROGEN

M3 - Conference proceeding contribution

SN - 9780980558685

SP - 263

EP - 265

BT - Smart science for exploration and mining

A2 - Williams, PJ

PB - JAMES COOK UNIV

CY - Townsville, QLD

T2 - 10th Biennial SGA Meeting of the Society for Geology Applied to Mineral Deposits

Y2 - 17 August 2009 through 20 August 2009

ER -

Genesis of the Urals VHMS deposits inferred from coupled Pb-Os isotope systematics

Abstract

Conference

Keywords

Fingerprint

Cite this