Our Team

Stephen Reford, B.A.Sc., P.Eng.

President, Senior Consulting Geophysicist

Stephen joined PGW in 1981 after a B.A.Sc. in Engineering Science (geophysics) from the University of Toronto. In 1994, he became a partner and Vice-President of PGW before being appointed President in 2016.

Throughout his 40 years at PGW, Stephen's expertise and leadership has garnered a reputation of being one of the most respected Geophysicists in the Exploration Geophysics Industry. He has managed and played a technical role on numerous projects for government agencies worldwide, including World Bank, UN and CIDA-sponsored projects. His prolific resume has allowed him to have on-site experience in: Canada, India, Thailand, Malaysia, Cameroon, Malawi, DR Congo, Burkina Faso, Angola, Mauritania, Uganda, Senegal, Morocco, Nigeria, Botswana, Brazil, Chile, Suriname, Guyana, French Guiana, Saudi Arabia, and Peru. He specializes in all aspects of airborne geophysics for mineral, hydrocarbon and groundwater applications.

He is also a director of IDPeX, PGW’s 1/3-owned consultancy in India.

Stephen is a member of the Canadian Exploration Geophysical Society (KEGS) and served on its executive committee from 1995-1999. He is also President of the KEGS Foundation, a non-profit foundation that awards scholarships to up-and-coming Geophysics Students. He is a registered Professional Engineer with the Professional Engineers Ontario. He is also a member of PDAC, SEG, ASEG and EAGE.

Edna Mueller-Markham, M.Sc., P.Geo.

Vice-President, Senior Consulting Geophysicist

Edna joined PGW in 1997 after obtaining a M.Sc. in Geology from McMaster University and a B.Sc. in Physics (geophysics) from the University of Toronto. In 2016 she was appointed as the Vice-President of PGW, and acts as the managing director dealing with day-to-day operations.

Edna specializes on quality control, processing, modelling and interpretation of magnetic, gravity, radiometric and electomagnetic data. Her roles in various projects has led her to have site visits to: Canada, Laos, India, Cameroon, Angola, Gabon, Saudi Arabia, Peru and Colombia. She has extensive experience provided technical training on geophysical theory, quality control, proper field practices, and geophysical software. She has given training in both English and French in Gabon, Cameroon, Laos, and in-person from PGW's Toronto office.

Edna is a member of KEGS and served on its executive committee from 2011-2015. She a registered Professional Geoscientist with the Professional Geoscientists of Ontario (PGO).

Peter Tschirhart, M.Sc., P.Geo.

Senior Consulting Geophysicist

Peter Tschirhart graduated from McMaster University in 2011 with a B.Sc in Earth and Environmental Science. Following undergraduate studies, Peter completed an M.Sc in Earth Science in 2013, also at McMaster University.

After graduation, Peter worked as a Geophysical Data Analyst at Sander Geophysics. He travelled extensively on numerous field projects across 4 continents performing QA/QC and data processing in aeromagnetics, radiometrics, and airborne gravity. He was also involved with several large magnetic and gravity interpretation projects. In January 2017 Peter joined PGW as a staff geophysicist where he has been involved with data processing, interpretation, QA/QC and modelling services. His time with PGW has sent him to India, Cameroon, Malawi, and Botswana.

Peter is a member of KEGS where he is currently serving on its executive committee. He is a registered Professional Geoscientist with PGO.

Ali Latrous, M.Sc., P.Geo.

Senior Consulting Geophysicist

Ali graduated in 1996 from Université des Sciences et de la Technologie Houari Boumediene with a B.Eng in Geophysical Engineering. He followed it up with a M.Sc. in Geophysics from Institut de Physique du Globe de Paris in 2000.

Following graduation, Ali specialized in providing technical training to government employees and industry professionals before working as a Geophysicist for Aeroquest Surveys. During this period post-graduation, he worked several field crews carrying out ground magnetic, IP, and resistivity surveys in several countries. From 2010 to 2018, Ali worked with Geotech Ltd. as a Senior Geophysicist specializing in their ZTEM™ system. Ali joined PGW in 2019, bringing his expertise in airborne EM to assist in QA/QC, interpretation, modelling, and machine learning services.

Ali is a member of KEGS and a registered Professional Geoscientist with PGO.

Skyler Mallozzi, M.Sc., G.I.T.

Geophysical Consultant

Skyler graduated from Carleton University in 2017 with a B.Sc. Honours in Earth Science with a Concentration in Geophysics. He completed his M.Sc. in Earth Science in 2019, also at Carleton University.

Following graduation, Skyler worked as a Geophysicist with De Beers Canada  in their Exploration Department. He worked with both the Targeting and Field Teams during his time there; with the Targeting team, he data compilation of thousands of legacy geophysical surveys of various methods; with the Field Team, he assisted in geophysical anomaly ground checking, sediment sampling, and kimberlite prospecting in Northern Ontario. Skyler joined PGW in August 2020 where he has been involved with data compilation and processing, interpretation, and QA/QC services.

Skyler is a member of KEGS where he currently serves as their Social Media Director. He also acts as the Student Outreach Coordinator and Social Media Manager for the KEGS Foundation. He is a registered Geoscientist-in-Training with PGO, but is currently in the application process to become a registered Professional Geoscientist.


  • PGW aims to be your partner in discovery using geological knowledge to enhance and constrain the geophysical interpretation of your data.
    - PGW