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Ph.D. Thesis Defence – April 24, 2018 – John Evangelatos

JOHN EVANGELATOS
B.Sc. Honours (Earth Science), McGill University, 2005
M.Sc. (Geology), University of New Brunswick, 2008
DEPARTMENT OF EARTH SCIENCE

THE GENESIS AND EVOLUTION OF
MAKAROV BASIN, ARCTIC OCEAN

9:30a.m., Tuesday, April 24, 2018
Room 3107, The Mona Campbell Building
1459 LeMarchant Street

EXAMINING COMMITTEE:
Dr. Carmen Gaina, Centre for Earth Evolution and Dynamics, University of Oslo (External Examiner)
Dr. Keith Louden, Department of Oceanography, Dalhousie University (Reader)
Dr. Gordon Oakey, Geological Survey of Canada (Atlantic), Bedford Institute of Oceanography (Reader)
Dr. John Gosse, Department of Earth Science, Dalhousie University (CoSupervisor)
Dr. David Mosher, Adjunct, Department Earth Sciences, Dalhousie University and Geological Survey of Canada- Atlantic, Natural Resources Canada, Bedford Institute of Oceanography (Co-Supervisor)
DEPARTMENTAL
REPRESENTATIVE:
Dr. James Brenan, Department of Earth Science, Dalhousie University
CHAIR:
Jure Gantar, PhD Defence Panel, Faculty of Graduate Studies

ABSTRACT

Plate tectonic theory commenced with the observation that continental margins fit together like pieces of a puzzle. No such fit is readily apparent to the margins of Amerasia Basin of the Arctic Ocean, resulting in a stubborn outlier to global plate-reconstructions. This problem persists partly because of a paucity of data in the perennial ice-covered seas. Makarov
Basin is well-positioned to address this problem, situated at the northern margin of Amerasia Basin, adjacent to Lomonosov Ridge. This study tests the hypothesis that this segment is a transform margin that resulted from rotational opening of Amerasia Basin. For this purpose, this study analyses the seismic stratigraphy, geomorphology, potential field and seismic
velocity data of Makarov Basin and surrounding areas. The data are mainly from a unique seismic line that transects Makarov Basin and onto Lomonosov Ridge.

The sedimentary cover averages 1.9 km-thick in Makarov Basin, with a maximum thickness of – 5 km in a northern deep subbasin. The deeper successions within the subbasin host interbedded volcanic and/or volcaniclastic material. A shift in sedimentary supply, from proximal to distal, is recorded after the onset of Cenozoic rifting that separated Lomonosov Ridge from the Barents-Kara Shelf and formed Eurasia Basin. Thereafter, sedimentation is largely pelagic to hemipelagic.

The crust of Makarov Basin is typically 9 to 11 km thick, except beneaththe subbasin where it is 5 km thick. The crust abruptly thickens to >20 km from Makarov Basin to central Lomonosov Ridgb. Results from gravity modelling reveal that the tectonic style of the Amerasian margin of Lomonosov Ridge varies from passive rifting to strike-slip along its length. The rhomboid shape of Makarov Basin, the straight and steep morphology of the Amerasian flank of Lomonosov Ridge, the presence of numerous sub-parallel ridges created by splay faulting and the abrupt crustal transition between the two provinces is evidence of transverse/transtensional tectonics along the central segment of the ridge. This result supports a rotational model of opening for Amerasia Basin, at least for its initial stages, and is a critical element to understanding the larger tectonic framework of the Arctic Ocean.

Defence Notice (PDF)

ERTH 6300 GRADUATE MINI-SYMPOSIUM – APRIL 11, 2018

On April 11, 2018,starting at 9:00 am, the ERTH 6300 Graduate Mini-Symposium will be held in the Milligan Room on the 8th floor of the Biology/Earth Sciences Wing of the Life Sciences Centre.

ERTH 6300 Graduate Mini-Symposium Schedule

4 graduate candidate will be presenting preliminary data from their thesis project.

  • Sydney Stahin, MSc candidate working with John Gosse
    TITLE OF PROPOSAL: Beaufort Formation Chronostratigraphy and Pliocene Landscape Evolution
  • Richard Chow, MSc candidate working with Yana Fedortchouk
    TITLE OF PROPOSAL: Volatile degassing and formation of different kimberlite facies as recorded in apatite
  • Yuqiu Zhao, MSc candidate working with Djordje Grujic
    TITLE OF PROPOSAL: Recurrence Interval of Large Earthquakes in the Eastern Himalaya
  • Mathilde Banjan, PhD candidate working with Dawn Kellett and Isabelle Coutand
    TITLE OF PROPOSAL: Late Mesozoic to Tertiary thermo-tectonic history of the Intermontane terranes, Canadian Cordillera.

MSc Thesis Defence – Taylor Campbell – April 20, 2018

M.Sc. THESIS DEFENCE

 by

 Taylor Jane Campbell

 DEPARTMENT OF EARTH SCIENCES

DALHOUSIE UNIVERSITY


“SEISMIC STRATIGRAPHY AND ARCHITECTURE OF THE JURASSIC ABENAKI MARGIN,

AT COHASSET-MIGRANT, AND POTENTIAL FOR DISTAL ORGANIC-RICH FACIES”

                                                                                   

PLACE:          The Milligan Room, 8th Floor Biology Wing, LSC, Dalhousie University    

 DATE:            Friday, April 20, 2018

 TIME:             10:00 a.m.

 

EXAMINING COMMITTEE:

 Dr. Laurence Davis                            Husky Energy, Atlantic Region                                   External Examiner

Dr. Mladen Nedimovic                       Dalhousie University                                                  Reader

 Mr. David Brown                                Canada-N.S. Offshore Petroleum Board                    Reader

 Dr. Grant Wach                                  Dalhousie University                                                  Supervisor      

Dr. John Gosse                                   Dalhousie University                                                  Chair

PLEASE NOTE:       A copy of the thesis is available in the main Earth Sciences Office

 

ABSTRACT

 This study uses well data, extensive 3D seismic data and geologic analogs to test and extend stratigraphic concepts and models in a mixed clastic-carbonate depositional setting: the Middle Jurassic to Early Cretaceous of the Sable Sub-basin, offshore Nova Scotia. The study focuses on basinward mapping of third-order depositional sequences identified in the Abenaki carbonate bank at Deep Panuke Field and addresses: source rock potential in coeval basinal calcareous mudstones; changes in bank margin morphology related to underlying basement; the transition from a dominantly carbonate system at the shelf margin to a fluvio-deltaic system, the Sable Delta, that extends to the Late Cretaceous; the presence of thick fluvio-deltaic sediments adjacent to basinal mudstones outboard of the carbonate bank.

These depositional systems are uniquely imaged by 3D seismic data in the area around the Cohasset L-97 and Migrant N-20 well penetrations. Core studies of wells which penetrated the Abenaki carbonate bank and field studies in the Lusitanian Basin, onshore Portugal, provide calibration and analogs to shallow water carbonates in the Cohasset area. Further ancient and modern analogs are discussed in Morocco and at the termination of the Great Barrier Reef in the Gulf of Papua.

Geological, petrophysical and geophysical interpretation methods are used to interpret the depositional cycles and stratigraphic framework of limestones and calcareous shales that were deposited in increasingly deeper water outboard of the Abenaki margin. This framework formed the basis for a 3D geocellular model that was populated with lithologies from well data via a seismic inversion. This model was interpreted in terms of environments of deposition and source rock potential.

The third-order sequence stratigraphic framework was modified from a framework established at Deep Panuke gas field where commercial production began in August 2013. This third-order chrono-stratigraphic framework (“Abenaki 1-7 surfaces”) incorporates multiple litho-stratigraphically defined formations: the Mohican, Mohawk, Mic Mac, Abenaki, Missisauga and Verrill Canyon formations. Thick fluvio-deltaic successions adjacent to basinal mudstones in the Migrant N-20 well are interpreted to be structurally controlled, deposited in local depocentres, that formed in response to sediment loading, listric faulting and mobile salt substrate.

Results from the study show that condensed sections of the distal carbonate depositional system in Abenaki 1-4 sequences have potential to host organic-rich material. The basinal shales of these sequences are estimated to have been deposited in up to approximately 200 m water depths and have type 2 source rock potential. A change in seismic signatures and facies occurs between Abenaki sequences 1-4 and Abenaki sequences 5-7 reflecting encroachment of the Sable Delta, and it is interpreted that the Abenaki 5-7 sequences have predominantly type 3 source potential, with some potential for a type 2 source in intervening calcareous mudstones.

Thesis Defence Webpage

 

The Marcos Zentilli Graduate Award

Zentilli-Picture-2005

In honour of Dalhousie Emeritus Professor of Economic Geology, Marcos was a member of the Department of Earth Sciences (Geology) fron 1973-2005. A pioneer in apatite fission-track geochemistry and beloved mentor, he shaped the lives  and careers of many Dalhousie geologists.

We invite you to support…

This award recognizes Marcos’ legacy by providing support to attract and retain graduate students of the highest calibre to conduct their studies in the Department of Earth Sciences.

Please support students in the Department of Earth Sciences today.

To give, please visit,  giving.dal.ca/zentilli

Marcos_Zentilli_Graduate_Award_2
PDF (13 Mb)

Dal Earth Sciences at the 2018 PDAC Convention in Toronto

The Dept held a joint alumni reception with the Faculty of Engineering on Tuesday night in the Nova Scotia Room at the Royal York Hotel.  Our special guest was Emeritus Professor Marcos Zentilli.  It was a great night of making new acquaintances and renewing old ones.  Here’s a photo of the whole group with the interesting backdrop of what appears to be Champlain having a feast in the new world.

2018_PDAC_ALUMNI_RECEPTION

Congratulations to  Erin Keltie for winning the 1st place masters student poster at PDAC 2018!

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If you are interested in her research, ere is a PDF of her poster.

Putting a Spin on Earth Sciences

This year’s Faculty-Graduate Student Curling Challenge was held at the Halifax Curling club on Friday 16 February.  It was touch and go for awhile, but the faculty managed to muster a strong team against the graduate students, who were the Challenge victors in 2017.

As per last year, PhD student Bryan Maciag organized the event and shared with us some of his curling talent – thanks Bryan!

Here’s Bryan showing Shannon Sterling the finer points, with one of our visiting graduate students, Falko, curiously looking on.

1

The faculty secret weapon was Richard Cox, who was genetically modified in his Scottish homeland to have porphyritic granite running through his veins, and bones.  Here’s Richard (far left) relaxing between ends, with the graduate student cohort excitedly waiting to watch and learn Richard’s masterful techniques.

2

The faculty, clever that they are, also managed to sneak in Sean “the evil leprechaun” Hartwell, just to throw the graduate students off guard.  Here’s Sean cleverly distracting Bryan with a beguiling limerick.

3

The final score.  I think it was a tie?

4

While the graduate students relax after the event, little do they know that the faculty is now putting the collective wisdom of a dozen PhDs to develop a winning strategy for next year.

5

EAGE: The Laurie Dake Challenge. Dalhousie Makes the finals

Dalhouise University was selected as one of the 10 finalists from around the world

Team Members: Graham Kerford, Sam Balcom, Jennifer Lee,  Massoud Alli, Colton Bentley

Advisor: Grant Wach

To participate in the European Association of Geologists and Engineers (EAGE) Petroleum Geoscience competition.

eage

The finalists will meet in Copenhagen in June for final competition where the students will present in front of a panel of industry experts. They will present their analysis of an oil and has field looking at all the data and history of field production.

Congratulations!