Diatremes,
Dykes, and Diapirs: Rrevisiting Ultra-alkaline to Carbonatitic
Magmatism of the Monteregian Hills GAC-MAC 2006 |
2006 Geological Association of Canada - Mineralogical Association of Canada two and one-half day field trip (May 18 to May 20) to the western intrusions of the Monteregian Hills, Canada. Day 1 focused on the diatremes, dykes, and the Oka carbonatite complex west of Montreal. Day 2 focused on the Mont Royal alkaline intrusion and Île Ste-Hélène. Day 3 was spent at Mont St. Hilaire with a visit to the Poudrette quarry, one of the world's most prolific mineral localities (>365 species identified from this locality), and a brief look at the mafic alkaline suites of the main intrusion. The field trip guide (GAC-MAC 2006) is available as a pdf file. |
|||
|
|||
Monts Bruno (l), St. Hilaire, and Rougemont (r) as seen from Mont Royal. |
|||
Île Bizard breccia pipe. The "backyard" exposure. | Limestone fragments in Île Bizard breccia pipe. | Investigating lower slopes of Île Bizard breccia pipe. Not the "backyard" exposure. | Syenitic segregations in monchiquite sill at Ste. Dorothée. |
Examining the sill at Ste. Dorothée. Rain makes the grass grow (photo by G. Duke). | Flooded pit at Oka. | Collecting from the dump at Oka. | Examining Oka drill core. The search for niocalite. |
A "gnat attack" while examining the Oka drill core (photo by G. Duke). | A well behaved "gaggle of geologists" leaving the Monastery pipe at La Trappe (photo by G. Stott). | Utica shale, country rock for the Mont Royal intrusion. | Aligned feldspars in melanocratic gabbro. Mont Royal. |
Syenitic veins cutting melanocratic gabbro. Mont Royal. | Deformed limestone at entrance to Cimetière Côte des Neiges. Mont Royal. | Adrian indicating the source of the aqueous phase at Île Ste.-Hélène (photo by G. Stott). | Hornfels dipping in toward intrusion. Poudrette quarry. Mont St. Hilaire. |
Examining outcrops in Poudrette quarry during the height of the monsoon. | Pegmatitic pod in nepheline syenite. Poudrette quarry. | Partially digested inclusion of coarse-grained syenite in porphyritic nepheline syenite. Poudrette quarry. | Fluorite in breccia. Poudrette quarry. |
Marble xenoliths, surrounded by reaction rims, in nepheline syenite. Poudrette quarry. | Breccia blocks by Lac Hertel (they really do exist). Mont St. Hilaire. | Group photograph at the Chalet. Mont Royal (photo by K. Yang). |
Return to Field Excursion Photos |