Who: David J. Reynolds

What: A Virtual Field Trip to the Greater Death Valley Region; Implications for interpreting highly-extended basins

The scale and rates of extensional tectonic processes in the Greater Death Valley Region (GDVR) are impressive and are similar to what is observed in the early stages of passive margin evolution. Exposures in the GDVR give insight into regions now covered with several kilometers of water and sediment. The GDVR is approximately 350km in width with some interpretations suggesting the original width (pre-Cenozoic extension) was only 100km, implying 250 km of extension (Wernicke et al., 1989; Snow and Wernicke, 2000). This extension is accomplished primarily by high displacement, low-angle normal faults, resulting in the exhumation of mid-crustal rocks that are now exposed in core complexes.

As revealed by long-offset seismic data, coupled with field observations, this degree of extension and its associated processes are fundamentally the same as those that control the development of highly extended basins and passive margins. Additionally, highly extended regions are often characterized by complex deformational histories (polyphase deformation, not all basins of the same age), that can be difficult to recognize using seismic and/or potential field data. Deconvolving these events is important when predicting the distribution of facies in the subsurface, as well as providing constraints on subsidence and heat flow histories.

The GDVR field area offers an opportunity to better recognize and evaluate these processes and understand the rates and geometries associated with them. Although this virtual trip is a poor substitute for seeing and mapping the structures in person, especially when it comes to appreciating the rates and scales that are operative, our goal is to use observation-based interpretations in order to determine the amount of extension and how different structures are manifest so that we might recognize them in the subsurface. To do so, we will make a dip transect, similar in scale to a longoffset seismic profile, along an intact extensional system from Las Vegas to the Panamint Mountains, then another with approximately a strike orientation along the Black Mountain Front, tracking constraints on the timing and magnitude of deformation and associated sedimentation along the way.

When: 11:00 a.m., Wednesday, September 23, 2020

Where: Join Zoom Meeting

Who: Felix Gradstein

What: The first 40 million years of the planktonic foraminifera from Canada to Dagestan

Lands & Minerals Sector Mining Field School: Hands-on Experiences with Canadian Minerals and Metals

Felix Gradstein(1), Anna Waskowska(2) and Larisa Glinskikh(3)

This invited seminar deals with: 1) Grand Banks exploration; 2) Jurassic planktonic foraminifera evolution, paleoceanography and commercial application; and 3) new digital microscopy that reveals remarkable slow, but modernistic evolution of these 'critters'.

When: 11:00 a.m., FRIDAY, February 14, 2020

Where: AGC Boardroom, 5th Floor Murray, Bedford Institute of Oceanography, Dartmouth, Nova Scotia

Who: Christopher Sangster

What: Predictive modelling of reservoir quality associated with reservoir distribution and the dissolution of K-feldspar during diagenesis
Lower Cretaceous, central Scotian Basin

The distribution and quality of the Lower Cretaceous reservoir sandstone units of the Scotian Basin is poorly understood, particularly in the deep basin. Exploration is further complicated by the widespread salt tectonism and the strong influence of diagenesis on reservoir quality. This research aims to predict reservoir quality by applying stratigraphic modeling techniques and petrographic studies to the Scotian Basin, simulating the distribution of potential reservoir sand intervals. It also investigates the influence of burial diagenesis on the breakdown of detrital K-feldspar and preservation of the resulting secondary porosity.

Models have been calibrated against reference wells and seismic surfaces, and implement a multidisciplinary approach to define simulation parameters. K-feldspar proportions were determined using scanning electron microscope back-scattered electron images, and are shown to decline with depth. No change in sediment source or evidence for influence of climate on feldspar proportions is seen, thus the decrease in feldspar is primarily related to dissolution with burial and the increased temperatures and fluid interaction during diagenesis. To asses the impact of the dissolution of K-feldspar on reservoir quality, its distribution has been simulated using forward stratigraphic modelling, and is compared to thermal modelling (to predict secondary porosity generation), fault mapping (to assess flux of fluids and hence porosity preservation), and sand distribution (to determine reservoir potential) to determine the risk on reservoir quality.

Sand is dominantly trapped on the shelf in all units, with transport into the basin along salt corridors and as a result of turbidity current flows occurring in the Upper Missisauga Formation and Cree Member. Additionally, sand appears to by-pass the basin beyond the down-slope edge of the study area. Based on predicted preserved secondary porosity, the sand deposits on the shelf and slope have a lower risk of poor reservoir quality than those in the basin, with the lowest risk along the shelf edge and upper slope of the central and western study area. In the basin, the lowest risk is located near the slope to basin transition, and is classified as moderate, with the sands predicted to be transported to the deep basin likely to have a high risk.

When: 11:00 a.m., Wednesday, February 5, 2020

Where: AGC Boardroom, 5th Floor Murray, Bedford Institute of Oceanography, Dartmouth, Nova Scotia

Who: Michael Parsons

What: Lands and Minerals Sector Mining Field School
Hands-on Experiences with Canadian Minerals and Metals

Our modern lives are full of gadgets, ranging from smart phones, personal computers, and gaming systems to hybrid cars, wind turbines and medical imaging equipment. Have you ever stopped to wonder what's inside all of these devices, and where the materials come from? This talk will explore the wide range of chemical elements that underlie our modern standard of living, discuss the main sources of these elements, and examine Canada's current and future role as an environmentally responsible supplier of these important minerals and metals. Here at Natural Resources Canada (NRCan), our staff are involved in all aspects of the mining life cycle, including exploration, development, operation, and mine closure. In response to the growing demand for minerals and metals, I helped to co-lead a Mining Field School for NRCan science and policy staff in June and October 2019 to active and decommissioned mining and mineral processing sites in Ontario and Quebec. The main goal of these trips was to showcase mining-related work undertaken by NRCan, strengthen interaction with the mining sector, and to discuss science and policy issues facing the Canadian mining industry now and in the future. This presentation will provide a virtual tour of the mining camps visited during these field schools and summarize the key challenges and opportunities faced by the modern mining industry.

When: 11:00 a.m., Wednesday, January 15, 2020

Where: AGC Boardroom, 5th Floor Murray, Bedford Institute of Oceanography, Dartmouth, Nova Scotia