Structural Control on the Formation of Pb-Zn Deposits: An Example from the Pyrenean Axial Zone

Pb-Zn deposits and specifically Sedimentary-Exhalative (SEDEX) deposits are frequently found in deformed and/or metamorphosed geological terranes. Ore bodies structure is generally difficult to observe and its relationships to the regional structural framework is often lacking. In the Pyrenean Axial Zone (PAZ), the main Pb-Zn mineralizations are commonly considered as Ordovician SEDEX deposits in the literature. New structural field analyzes focusing on the relations between mineralization and regional structures allowed us to classify these Pb-Zn mineralizations into three types: (I) Type 1 corresponds to minor disseminated mineralization, probably syngenetic and from an exhalative source. (II) Type 2a is a stratabound mineralization, epigenetic and synchronous to the Variscan D1 regional deformation event and (III) Type 2b is a vein mineralization, epigenetic and synchronous to the late Variscan D2 regional deformation event. Structural control appears to be a key parameter in concentrating Pb-Zn in the PAZ, as mineralizations occur associated to fold hinges, cleavage, and/or faults. Here we show that the main exploited type 2a and type 2b Pb-Zn mineralizations are intimately controlled by Variscan tectonics. This study demonstrates the predominant role of structural study for unraveling the formation of Pb-Zn deposits especially in deformed/metamorphosed terranes.

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The predominant role of IP3 type 1 receptors in activation of store-operated Ca2+ entry in liver cells

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/j.bbamem.2010.12.013 ◽

2011 ◽

Vol 1808 (3) ◽

pp. 745-751 ◽

Cited By ~ 3

Author(s):

L. Jones ◽

L. Ma ◽

J. Castro ◽

T. Litjens ◽

G.J. Barritt ◽

...

Keyword(s):

Liver Cells ◽

Predominant Role

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The clonal and molecular aetiology of emergency dendritic cell development

10.1101/2020.05.28.120188 ◽

2020 ◽

Author(s):

Dawn S. Lin ◽

Luyi Tian ◽

Sara Tomei ◽

Daniela Amann-Zalcenstein ◽

Tracey M. Baldwin ◽

...

Keyword(s):

Progenitor Cell ◽

Immune Cell ◽

Cell Development ◽

Natural Immunity ◽

Flt3 Ligand ◽

Predominant Role ◽

Transcriptional State ◽

Cellular Barcoding

SummaryExtrinsic regulation of single haematopoietic stem and progenitor cell (HSPC) fate is crucial for immune cell development. Here, we examine the aetiology of Flt3 ligand (Flt3L)-mediated emergency development of type 1 conventional dendritic cells (cDC1s), which results in enhanced immunity against infections and cancer. Using cellular barcoding, we demonstrate a predominant role of enhanced clonal expansion and moderate contribution via recruitment of additional cDC1-generating HSPCs. The selective cDC1 expansion occurs primarily via multi-/oligo-potent clones, without compromising output to other lineages. To understand the molecular hallmarks early during a Flt3L response, we develop Divi-Seq to simultaneously profile cell division history, surface phenotype and transcriptional state of single HSPCs. We discover that Flt3L-responsive HSPCs maintain a proliferative ‘early progenitor’-like state, which leads to selective emergence of CD11c+cKit+ transitional precursors with high cellular output to cDC1s. These findings inform the mechanistic action of Flt3L in natural immunity and immunotherapy at a clonal level.

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Immunoglobulin isotypes reveal a predominant role of type 1 immunity in multiple sclerosis

Journal of Neuroimmunology ◽

10.1016/s0165-5728(01)00436-2 ◽

2001 ◽

Vol 121 (1-2) ◽

pp. 120-125 ◽

Cited By ~ 20

Author(s):

B Greve ◽

C.G.M Magnusson ◽

A Melms ◽

R Weissert

Keyword(s):

Multiple Sclerosis ◽

Predominant Role ◽

Immunoglobulin Isotypes

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The Orogenic Crixás Gold Deposit, Goiás, Brazil: A Review and New Constraints on the Structural Control of Ore Bodies

Minerals ◽

10.3390/min11101050 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1050

Author(s):

Stanislav Ulrich ◽

Steffen Hageman ◽

Juliana Charão Marques ◽

Frederico Lana A. R. Figueiredo ◽

João E. F. Ramires ◽

...

Keyword(s):

Gold Deposit ◽

Structural Control ◽

Gold Mineralization ◽

Current Knowledge ◽

Current Model ◽

Regional Scale ◽

Structural Data ◽

Stratigraphic Sequence ◽

Structural Framework ◽

Ore Bodies

A review of the current knowledge of lithostratigraphy, geochronology, mineralogy, alteration, fluid chemistry and structural data is provided in order to discuss the main controls on mineralization in the Crixás gold deposit and the existing structural framework and evolution. Gold mineralization at Crixás represents orogenic upper mesothermal to lower hypothermal types developed within the overturned Paleoproterozoic (Rhyacian) stratigraphic sequence. The structural data indicates that upright folding of the stratigraphy and formation of a distinct S1 foliation characterizes D1 deformation. This controls the formation of laminated quartz veins, precipitation of Au-rich sulfides, and the development of NW trending orebodies. Localized F2 folding of D1 structures and strong L2 stretching lineations characterizes the D2 event. This localized F2 folding created oreshoots trending W-WNW within distinct orebodies. The D2 deformation is associated with the precipitation of native Au. The ‘bulk plunge’ of these orebodies is a combination of both plunges defined by D1 and D2 deformation events. A critical assessment of lithostratigraphic and structural data reveal two possible tectonic scenarios operating during the Paleoproterozoic. The first possible tectonic scenario considers sagduction and the development of a regional-scale synclinorium, followed by tilting and localized folding of D1 structures. The second scenario, which is similar to the current model, considers accretion producing a synclinorium, followed by thrusting. Based on the current knowledge, both models are considered to be permissible and a series of focused research studies are proposed to test both the current and the new tectonic models.

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