Tag: geology

September 26, 2019

Public lecture: Hydrothermal fields from the Mid-Atlantic Ridge – The role of brecciate rocks in ore formation

By Isabel Costa (INCITE and IDL-FCUL)

Lucky Strike and Menez Gwen hydrothermal fields are located in the Mid-Atlantic Ridge (MAR), southwest of the Azores islands. In the areas surrounding the active sites, the alteration processes affecting basaltic rocks are prominent and form hydrothermal breccias by the circulation of low temperature hydrothermal fluids in diffuse vents. These breccias play an important role in the protection of subseafloor hydrothermal sulphide deposits by forming an impermeable cap due to the high content in siliceous material. Since the discovery and description of recent mineralized submarine hydrothermal deposits, comparison with ancient volcanic massive sulphide deposits is appropriate. Thus, the model for the formation of the Atlantic brecciated rocks can explain some of the processes taking place in the early phase of development of old deposits, where equivalent siliceous material is found in the hanging wall of the ore bodies.

 

0
December 4, 2018

Public lecture: Seafloor Mineral Resources

Public lecture: SEAFLOOR MINERAL RESOURCES by Prof. Vesselin Dekov

on 4th Dec., 2018, 6:00pm

@ ISE, USJ – Institute of Science and Environment of the University of Saint Joseph. Speakers´ Hall. Rua de Londres 106, Macau, China. 中國澳門倫敦街一零六號（環宇豪庭三樓）

Abstract

The lecture will discuss the main characteristics, types, mode of formation, occurrence and economic value of the major seafloor mineral resources. It will comment on the mineral potential of the continental margins and formation of marine placers, on the formation and possible mining of the polymetallic Mn-nodules at the abyssal plains, on the deposition of Co-rich Fe-Mn-crusts at the seamounts, and on the spectacular polymetallic hydrothermal sulphides precipitated at mid-ocean ridges, back-arc basins and volcanic arcs. The lecture is designed for students, researchers but also for non-professionals.

 

 

 

0
November 13, 2018

Visit: Prof. Ágata Dias visited the Dep. of Earth Sciences of the HKU

On 13th of November Prof. Ágata Alveirinho Dias visited the department of Earth Sciences of the University of Hong Kong.

She met Prof Mei-Fu Zhou, Prof. Zhao, Prof. Min Sun and Prof. Jin and worked in the ICP-MS lab running Hf isotopic analyses on zircons from granites of Macau

0
May 1, 2018

Visit: Head from COMRA (China) and the Head of EMEPC (Portugal) visit to ISE

The head from COMRA (China) and the Head of EMEPC (Portugal) visited us on May 2015

Aldino Santos de Campos: Head of the Task Group for the Portuguese Continental Shelf Extension / Estrutura de Missão para a Extensão da Plataforma Continental  (EMEPC): http://www.emepc.pt/

LIU Feng: Secretary-General of China Ocean Mineral Resources R&D Association / 中国在国际海底区域的活动及“蛟龙号”载人潜水器的海底发现 (COMRA): http://www.comra.org/2014-04/29/content_6856835.htm

They came to participate in the following exhibition

0
March 25, 2018

Meeting: New geochemical constraints on I-type granites of Macao: evidences for fractional crystallization and petrogenetic affinities with Jurassic-Cretaceous granites in SE China.

Quelhas P, Mata J, Lou U T, Ribeiro M L, Borges R, Dias Á (2018) I-type granites of Macao: evidences for fractional crystallization and petrogenetic affinities with Jurassic-Cretaceous granites in SE China. XIV Congresso de Geoquímica dos Países de Língua Portuguesa e XIX Semana de Geoquímica (XIV CGPLP/XIX SG, 25-29 March 2018, Trás-os-Montes e Alto Douro, Portugal

Poster presented by Pedro Quelhas (ISE, Nacau; IDL, Portugal)

0

Earth Sciences

February 6, 2018

EArth and Marine Sciences

Our studies combine tools in mineralogy and petrology, geochemistry (including radiogenic and stable isotope geochemistry) and cartography to research the following two topics:

DEEP-SEA HYDROTHERMAL SYSTEMS AND MINERAL DEPOSITS

The discovery of hydrothermal fields on the seafloor was one of the greatest scientific discoveries of the last century not only for the earth sciences but also for the life sciences. These systems are oasis of life in the otherwise inconspicuous seafloor where vents emanate hot fluids rich in metals that are used as an energy source by unique and spectacular vent-associated organisms. For this reason, the study of hydrothermal systems may provide clues on diverse topics such as how live can thrive in extreme and toxic conditions or how potential ore resource are formed. Our research on seafloor hydrothermal systems aims to understand the genesis, evolution and distribution of hydrothermal deposits in the deep-sea. It is mainly focused in the Mid-Atlantic Ridge (MAR) and in the Southwest Indian Ridge (SWIR). The main goals of this research are: to understand the contribution of mafic and ultramafic rocks on the deposition of hydrothermal ore deposits; to contribute with the development of tools for the detection of SMS deposits either active and discrete, diffuse and inactive; to contribute for the geochemical and mineralogical characterization of deep-seafloor deposits both on active and discrete hydrothermal; to understand the role of  sub-seafloor ore-forming hydrothermal systems on the preservation of sulphide minerals.

 

PROJECTS:

SWIMAR– The role of ultramafic-hosted hydrothermal systems in the formation of seafloor deposits: comparison between SWIR and MAR fields / 超基性岩系海底熱泉系統於海床熱液礦床扮演之角色:以 SWIR 及 MAR 熱泉系統相互比較為例

InterRidge WG – Working Group on Seafloor Massive Sulfides along Mid-Ocean Ridges

BLUE MINING – Breakthrough Solutions for the Sustainable Exploration and Extraction of Deep Sea Mineral Resources.

GEOLOGY OF MACAO

Macao is located on the Southeast (SE) China coast, south of Guangdong Province, about 50 km west of Hong Kong. In this area, there is a predominance of granitic intrusions that belong to the ~ 3500 km long and ~ 800 km wide NE-trending magmatic belt cropping out on the SE part of the Cathaysia Block. 

Our research includes the study of the origin and evolution of the magmas of Macao, as well as the dating of its magmatic events. It has further allowed developing a detailed digital cartographic map of the igneous rocks of Macao, and to contribute to a deeper understanding of the South China tectono-magmatic evolution. 

PROJECTS

MagIC– Petrology and Geochemistry of Igneous Rocks from Macao: Implications for the Crustal Evolution of Southern China / 澳门火成岩之岩石学与地球化学—对华南地壳演化的影响).

 To know more about the geology of Macau click here.
0

Ágata Alveirinho Dias (Á. A. Dias)

November 25, 2014

ÁGATA ALVEIRINHO DIAS

ASSOCIATE PROFESSOR

AUTHOR IDENTIFIERS

FORMATION: 
PhD in Geology (Crystallography, Mineralogy and Metallogeny), UL; MSc in Dynamic Geology, FCUL; Graduation in Geology, FCUL.

POST-DOC ACTIVITIES: 
(1) Arctic ultra-low spreading ridges: Jan Mayen and Loki’s Castle Hydrothermal fields, integrated in an European project (H2Deep-EUROCORES);

(2) Seafloor hydrothermal systems and associated mineral deposits in the Portuguese EEZ and adjacent areas (FCT: SFRH/BPD/68648).

CURRENTLY: Associate Professor and PI at ISE – USJ, Mo / Researcher at Instituto Dom Luis / Associated Lab

RESEARCH INTERESTS

Marine geochemistry, Mineralogy and Petrology; Deep sea hydrothermal systems and associated ore deposits; Magmatic and Ultramafic systems; Isotopic geochemistry and geochronology.

OCEANOGRAPHIC CRUISES
(Marine fieldwork)

Luso2009 – Scientist in on board of NRP Almirante Gago Coutinho (PT) with the ROV (Remotely Operated Underwater Vehicle) Luso; Governmental Task Group for the Portuguese Continental Shelf Extension (EMEPC); Azores island slopes geomorphology and geology and scientific studies for the Portuguese continental shelf extension in the Atlantic Ocean. Coordinator of survey dives at AMAR region.

Luso2008 – Scientist in on board NRP Almirante Gago Coutinho (PT) with the ROV Luso; Scientific studies for the Portuguese continental shelf extension in the Atlantic Ocean; Governmental Task Group for the Portuguese Continental Shelf Extension (EMEPC); Coordinator of the sediment corers sampling PI: Manuel Pinto de Abreu e Nuno Lourenço.

H2Deep (leg)- Scientist and gravity core drilling coordinator at leg 2, on board of G.O. SARS (Norway) with the ROV Bathysaurus; Survey of hydrothermal systems from Ultraslow spreading ridges. European cruise (EuroMARC Project).

CD167 (SEAHMA) – Scientist and gravity core drilling coordinator on board of RRS Charles Darwin (UK). The aim of the cruise was the geological and geophysical survey of the Saldanha hydrothermal system (Mid-Atlantic Ridge).

SEAHMA 1 – Scientist on board of Atalante (IFREMER) with ROV Victor. MAR seafloor research Portuguese mission (Seahma project/FCT); Participation as researcher and responsible of ROV research dives (FCUL).

SALDANHA – Scientist on board of NADIR (IFREMER), with a deep diving submersible – NAUTILE  (IFREMER). MAR seafloor research. Participation as researcher and coordinator of one of the Nautile submersible dives. Portuguese and French mission financed by Portuguese Government funds (Programa PRAXIS XXI).

PLAMIBEL I – Junior scientist on board Auriga oceanographic vessel. Portuguese mission (IH – Portuguese Hydrographic Institute) with collaboration of Bordéus University. Research participation. Study of the Portuguese continental shelf between Douro and Minho rivers and the turbiditic plumes connected with rivers from northern.

SELECTED RESEARCH PROJECTS

SeaMar – InSituMin projectIn-situ trace elemental and isotopic constraints on modern seafloor massive sulfide mineralization – 现代海底块状硫化物成矿作用的原位微量元素和同位素限制 FDCT File No.: 0041/2021/A1, 2021-2024 (Principal Investigator)

SWIMAR – The role of ultramafic-hosted hydrothermal systems in the formation of seafloor deposits: comparison between SWIR and MAR fields/超基性岩系海底熱泉系統於海床熱液礦床扮演之角色:以 SWIR 及 MAR 熱泉系統相互比較為例. FDCT File No.: 002/2018/A1, 2018-2021 (Principal Investigator)

SMSMOR – Seafloor Massive Sulfides Resource along Mid-Ocean Ridges. InterRidge Working Group. on http://www.interridge.org/WG_SMS_MOR (team member)

Mag.I.C. – Petrology and Geochemistry of Igneous Rocks from Macao: Implications for the Crustal Evolution of Southern China. FDCT File No.: 043/2014/A1, 2015-2018.

BLUE MINING – Breakthrough Solutions for the Sustainable Exploration and Extraction of Deep Sea Mineral Resources. FP7 (7th research framework programme), EU Research Projects. Proj. ref.: 604500, 2014-2018

H2DEEP – Ultra-slow spreading and hydrogen-based deep biosphere (H2DEEP). EuroMARC Project  (ESF) No. ERAS-CT-2003-980409 of the European Commission. EUROCORES Program  – EuroMarc /0001/2007, 2007-2013

SEAHMA – Seafloor and Sub-seafloor Hydrothermal Modelling in the Azores Sea POCTI/P/MAR/15281/1999. 2001-2008 (team member)

MOMAR – Monitoring the Mid-Atlantic Ridge: MOMAR I, 1998; MOMAR II, 2002.

AMAR – Localização e Caracterização de Fontes Hidrotermais no Segmento AMAR: FCT (Praxis XXI) 1997-98

AMORES – Azores. Mid-Oceanic Ridge Ecosystem Studies: MAS3-CT95-0040) – EU – MAST III 1996 – 1998 (Team member)

MARFLUX / ATJ – Study of Hydrothermal Fluxes in the Azores Triple Junction – EU – 1994-1996

SCIENCE SPREADING PROJECTS:
“The Earth’s Last Frontier – Mysteries of the Deep Sea / 地球最後的樂土 – 深海探索 ” Macau Foundation project Ref. No. MF/2014/25, May 2015. (coordinator)

“Mesozoic magmatism of Macao and Hong Kong in the context of SE China geodynamics – 澳門 與香港的中生代岩漿作用”, Macau Foundation project Ref. No. MF/2016/08, March 2017 (Coordinator)

Others:

“Wetland ecosystems as a nature-based solution for climate change adaptation and mitigation in Macao” CTW/2021 (team member)

“Nature-based solutions for a cleaner and safer Macao” CTW/2020 (team member)

 

SELECTED PUBLICATIONS

SELECTED COMMUNICATIONS

0