2022 Annual Meeting
Sudbury, ON
May 10 & 11

Accommodation

Registration

Field trips

Sponsors

ILSG Student Research Fund

Goldich Medal Guidelines and Award Winners

Eisenbrey student awards

Student paper awards

ILSG main page

Links

1. A Traverse Across the Sudbury Impact Structure (Sunday, May 8 and Monday, May 9, 2022)

Leaders: W. Bleeker, M. Lesher and others

This 2-day field trip is a traverse across the deformed 1850 Ma Sudbury impact structure, from the older country rocks and brecciated target rocks to the south of the preserved melt sheet, across the entirety of the folded impact structure, melt sheet, and crater fill, and onto its northern rim. Day 1 will concentrate on the regional cross-section/traverse and will introduce many of the key aspects (and controversies) associated with the structure. Day 2 will finish the regional traverse and allow time to examine some of the ore environments in more detail, along the basal contact of the differentiated melt sheet and into the brecciated footwall.

Note 1: ore environments to be examined are dependent on company approval to access properties, as well as the evolving situation regarding COVID.
Note 2: This trip is a more detailed examination of the Sudbury impact structure than that offered by post-meeting trip 4. Trip 4 provides more of an overview of the structure.

5. A cross-section through the Huronian Supergroup at Elliot Lake, Ontario (Saturday, May 7, 2022)

Leader: R.M. Easton

This 1-day field trip will be a modification to the original field trip that was run by the ILSG in 2006. The trip will start and end in Sudbury. The trip provides an opportunity to view a near continuous section through all 4 groups of the Huronian Supergroup in an area of low-metamorphic grade and with excellent preservation of primary sedimentary structures. All field trip stops are located along roadways, and the trip is not physically demanding.

2. Geology of the Grenville Front in the Sudbury area (Sunday, May 8, 2022)

Leader: R.M. Easton

Through a mixture of previous and newly identified stops, on this 1-day trip we will examine the Grenville Front, the boundary between the Paleoproterozoic Southern and the Mesoproterozoic Grenville provinces in the Sudbury area. The first half of the trip will focus on the Grenville Front, whereas the second half of the trip will examine recently studied (fall 2021) exposures along Highway 69 located within the Nepewassi domain of the Grenville Province and in the Grenville Front tectonic zone. Discussion will focus on the disappearance of identifiable Huronian Supergroup rocks south of the Grenville Front, as well as key marker units, such as the Sudbury dike swarm (circa 1235 Ma). In addition, we will examine granulite-facies rocks within Nepewassi domain located only 15 km southeast of the Grenville Front. All field trip stops are located along roadways, and the trip is not physically demanding.

3. Magmatism and Brecciation in the Footwall Rocks, southwestern Sudbury Structure (Thursday, May 12, 2022)

Leaders: C. Gordon, C.A. Généreux and B. Clarke

This 1-day field trip will examine footwall rocks in the South Range of the world-renowned Ni-Cu-PGE producing Sudbury Igneous Complex (SIC). The field trip visits the southwestern exposure of the Sudbury impact structure in Denison and Drury townships, approximately 50 km west of Sudbury. Footwall rocks in the South Range consist of metavolcanic and metasedimentary rocks of the Paleoproterozoic Huronian Supergroup crosscut by numerous mafic intrusions of various ages, as well as economically significant SIC-related offset dikes, Footwall breccia and Sudbury breccia. Post-SIC deformation folded the Huronian rocks and produced reverse-dextral shear zones throughout the area. This field trip will focus on 1) SIC-related breccias and offset dikes, 2) Huronian volcanism, 3) regional deformation, and 4) Proterozoic mafic intrusions in the South Range. Field trip stops are located near or along roadways and trails.

4. An overview of the geology of the Sudbury Structure (Thursday, May 12, 2022)

Leader: S Peloquin

This 1-day field trip will provide an overview of the Sudbury Structure, one of the most prolific nickel camps in the world and the remnant of one of the world’s largest impact craters. The sites visited will provide a cross-section of the area from the footwall rocks through the Sudbury Igneous Complex and the crater-fill sediments of the Whitewater Group. In the footwall rocks, the evidence for the impact origin of the structure include Sudbury Breccia (pseudotachylite) and shatter cones. The nickel deposits formed at the base of the Sudbury Igneous Complex, and in the associated quartz-diorite “Offset” dikes. The first of the crater-fill units, the Sandcherry Member of the Onaping Formation, is fallback breccia from the impact. The subsequent crater-fill units, the Onwatin and Chelmsford formations will also be visited.

Note 2: This trip provides an overview of the Sudbury impact structure. For those of you interested in a detailed examination of the Sudbury impact structure, you should sign up for trip 1.