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Dalhousie University Petroleum Geoscience Field Methods Trinidad
Offshore Energy Research Association of Nova Scotia (OERA)
to fulfill requirements of the Graduate Student Research Travel Program
Basin and Reservoir Laboratory
Department of Earth Sciences
Department of Oceanography
Table of Contents
Benefits and Outcomes of Travel and Significance to Nova Scotia 4
Outcomes Darragh OConnor 8
Significance to Nova Scotia Darragh OConnor 8
Outcomes Alex Hurley 10
Significance to Nova Scotia Alex Hurley 12
Trip Itinerary 14
*Front cover image: sketch of a scarlet ibis, the national bird of Trinidad and Tobago
The Petroleum Geology Field Methods course at Dalhousie University is a collaborative course with
students from Atlantic Canadian Universities, the University of the West Indies (UWI), and professionals
from both Trinity Exploration & Production and Petrotrin. The course focuses on collaboration between
students and professionals in order to define associations between offshore and onshore geology
through field-based and laboratory outcrop, core, and log analyses (Fig. 1). The course is comprised of
three sections: pre-trip literature review of Caribbean geology involving reports on relevant petroleum
systems elements, field and laboratory exercises on the Island of Trinidad, and a presentation post trip.
Students are encouraged to work collaboratively with Trinidadian professionals in order to learn the
application methods of classroom taught concepts.
The course emphasizes the importance of onshore analogues for offshore petroleum systems that are
relevant for offshore Nova Scotia. Trinidad provides an overview of the effects of compressional and
extensional tectonics in the development of petroleum systems. This is best viewed through fluvial-
estuarine, shelf margin delta, and deepwater depositional system outcrops, along with the occurrence
Figure 1: Left A group of Dalhousie University students, UWI students, Trinity E&P employees, and trip organizer Grant
Wach along the beach at Cedros Bay. At this location deltaic sequences and abandonment deltaic lobes were described.
Right Dalhousie University students with Petrotrin employees outside the Petrotrin core laboratory. Students described
and interpreted offshore core to gain insight on the similarities between offshore and onshore geology
of mud volcanoes and oil seeps (Fig. 2). Subsurface data from offshore Trinidad, provided by Trinity
Exploration & Production and Petrotrin, allows students to build a framework for understanding
subsurface geology. Overall, the combined teams and new datasets provide opportunities for students
to conduct petroleum geosciences research on analogues relevant to offshore Nova Scotia geology.
The following topics are introduced in both the laboratory and field:
Basin tectonics and structural setting
Caribbean tectonics and seismicity
Trinidad structural evolution
Source rock, maturation, and overpressure
Source rock, fluid migration, and trap formation
Mud volcanoes, shale tectonics, petroleum migration
Oil and gas generation in the northern and southern basins
Depositional systems and modern day analogues
Figure 2: Left Active petroleum seeps in the city of San Franado, found near the backyard of a family residence. These
oil seeps appear as hydrocarbons travel from depth to surface through interconnected fault systems.
Right An active mud volcano near Piparo, located in central Trinidad. The mud volcano demonstrates the overpressure
of a petroleum system, often associated with active tectonism.
Accommodation space and basin fill
Mechanisms for sediment transport and settling rates
Modern fluvial and deltaic systems
Margin delta and slope reservoir characterization
Outcrop and core descriptions, gamma ray and permeability readings
Resource evolution of modern oil sand open pits
Health, safety, and environmental lectures
A unique component to the course is the addition of industry instructors (e.g. Petrotrin, BP, and Trinity
E&P) who assist in field and laboratory exercises. Their expertise in Trinidadian geology gave us and
Dalhousie and other students from Atlantic Canadian universities an excellent opportunity to develop
the necessary training for future careers in the petroleum industry.
Benefits and Outcomes of Travel and Significance to Nova Scotia
Trinidad is an exceptional location for the study of petroleum geoscience. The island offers remarkable
outcrop which clearly demonstrates petroleum system elements of source, seal, reservoir, trap, and
migration; all of which are required in forming an effective petroleum system. The thick reservoir and
seal packages of deltaic deposits (Fig. 3); the active overpressure shown through mud-volcanoes; the
over mature Northern Range organic rich source rock; the large number of faults indicating tectonic
activity; and the many oil seeps are examples of petroleum systems elements on the island of Trinidad.
In order to better understand the formation of petroleum system elements, the trip involved studying
modern wetlands and deltaic systems. Researching modern depositional systems, we were able to use
present day deposition models as keys to decipher and understand the formation of outcrop.
Aside from containing world-class outcrops and modern depositional analogues, Trinidad has a number
of other benefits in the study of petroleum geoscience. These benefits are:
1. The island is approximately 4700 km2, or about half the size of Cape Breton Island. This allows
for daily trips to be completed from the lodge to points of interest, all within reasonable time.
The longest period spend travelling from point to point was approximately two hours.
2. The island is a current hydrocarbon producing nation. Many of the rock formations seen on the
coast extend far into the subsurface of offshore Trinidad. The Trinidadians have learned to
exploit their well exposed onshore geology to aid in understanding and producing of offshore
subsurface reservoirs. This connection between onshore and offshore geology is a vital point of
proof when teaching and learning about petroleum system elements. Observations are made on
outcrop, then interpretations on how they formed, theories are conceived on how these would
produce hydrocarbons, and then offshore platforms are seen producing from these same
Figure 3: A collaborative effort amongst
Dalhousie students and Trinity E&P and
Petrotrin employees to try and piece
together the depositional history of this
outcrop. The outcrop is part of a known
deltaic sequence which often forms
both reservoir and sealing units. Both
of these petroleum system elements
are seen here: gray sediments are fine
grained silts and sand producing sealing
units and yellow sediments are clean
sands which produce hydrocarbon
reservoirs. A fault also highlights the
past tectonic influence on this system.
This deltaic system is an analogue for
the depositional systems of the sable
field offshore Nova Scotia.
reservoirs. These same procedures are being used to aid in describing reservoirs offshore Nova
3. There is a strong connection between academic, industrial, and governmental groups in Trinidad
with Dalhousie University, in part to close ties between Grant Wach and geologists of Trinidad.
This connection gives students the opportunity to meet and learn from Trinidadian geologic
professionals. The University of West Indies is a current member of the Atlantic Association of
Universities, again connecting Dalhousie University to UWI. Trinity Exploration & Production
often collaborates in field participation by sending a number of young geologists, engineers, and
chemists, as well as experienced managers, to both learn from and teach us. Petrotrin, the
petroleum company of Trinidad and Tobago, invited all Dalhousie University course participants
to study offshore core and to learn from some of the Worlds top biostratigraphers. Trinidad is
known to be one of the founding nations in biostratigraphy, giving students a unique
opportunity to meet the founding fathers of modern petroleum geoscience biostratigraphers.
4. Hydrocarbon production is clearly integrated into the Trinidadian culture. The mesh of
hydrocarbons and culture is shown in political relations, national monuments, employment and
the economy, and day to day life. A national monument in Trinidad is Naparima Hill, located in
the city of San Fernando. Culture and petroleum are tied together once again as the hill is the
only outcrop of the petroleum systems source rock, known as the Naparima Hill Formation.
The economy also s