Minh Ngọc Schimmelmann

Mrs. Minh Ngọc is Arndt Schimmelmann’s bilingual Vietnamese wife who loves traveling with her husband. In 2013, Arndt and Minh Ngọc took part in the International Symposium on Large Igneous Provinces of Asia in Hanoi, Vietnam, where the Schimmelmanns met and talked to Dương Nguyễn-Thùy – a young lecturer and petrologist/geochemist at Vietnam National University who happened to be a conference organizer.  Dương initially hesitated to engage with Indiana University in a research project. But Minh Ngọc and Arndt did not give up. With Minh Ngọc‘s persuasion in both Vietnamese and English, Dương began planning for international research in 2014, which grew into a number of successful collaborative research projects.

Arndt and Minh Ngọc Schimmelmann at the 14th International Conference on Gas Geochemistry 2017, ICGG-14, 24-28 Sep., Wrocław and Świeradów, Poland.

In May 2015 the first joint field work targeted caves on Cát Bà island (Hải Phòng city) and in the Đồng Văn Karst Plateau Geopark (Hà Giang Province) to measure methane in cave air.

During the early research phase, Minh Ngọc and Dương worked hard to organize field work, establish trust with governmental officials, and arrange for transportation and logistics on Cát Bà island (Hải Phòng) and in Đồng Văn, Hà Giang (December 2015). Their success was the foundation for our expanding research. Above: Minh Ngọc and Dương at the 4th International Conference on Radioecology & Environmental Radioactivity, 3-8 September 2017, Berlin, Germany.

With the expansion of our methane research project, Dương invited several Vietnamese collaborators and included graduate students from her faculty at VNU. The group at large needed a fitting name. Dương and her VNU colleague Hướng founded the EOS Research Group. Over the years, Arndt and Minh Ngọc visited occasionally to work with EOS group members and to train EOS students. Our collaboration within a close network of friends and family builds on essential virtues of the Vietnamese culture that makes our success possible.

Above: During a visit to the EOS lab in January 2018, Arndt discussed with group members a strategy to make thin sections from sediment cores.
Arndt demonstrates to Dương, Hướng, and Nguyệt a possible way to make thin sections from sediment cores at the EOS lab in January 2018.
Arndt and Minh Ngọc’s son Jan is currently a M.Sc. student at Bremen University in Germany. Since 2016, Jan has been participating in EOS field work in maars near Pleiku city in the Central Highlands of Vietnam. He built a lightweight and inexpensive core recovery device named “autonomous sediment corer with pneumatically operated core catcher” for use in remote regions and in developing countries like Vietnam. Jan also assisted in measuring environmental radon geohazards in caves and earthen dwellings in Hà Giang province. Above: Arndt, Jan and Hướng are using anodically charged stainless-steel blades to split the sediment in a sediment core in the EOS lab at VNU in December 2017.
The last three years of collaboration with the Schimmelmanns led to numerous international contacts. We are lucky to have many supportive friends in academia around the world. Above: Dr. Antti Ojala from the Geological Survey of Finland is an expert on laminated sediments, cesium-137 dating, and the magnetic characterization of sediment. Antti joined our EOS coring campaign in Biển Hồ maar lake, Pleiku city, in November 2017.
Arndt helps Minh Ngọc adjusting her helmet before entering Minh Châu cave during our second phase of field work on Cát Bà island in November 2015.
Minh Ngọc played a key role in our international research team with her bilingual ability to foster clear mutual understanding in logistic matters. Above: Arndt explains to Minh Ngọc the significance of methane experiments in Minh Châu cave during the second phase of field work on Cát Bà island in November 2015.
Minh Ngọc is a cultural ‘bridge’ for introducing Vietnamese customs to foreign friends. Above: Group lunch in the route to Đồng Văn, Hà Giang, December 2015. Professor Phương tried to impress Arndt by holding two peanuts with chopsticks. In response, Arndt cheated by holding four peanuts that were secretly impaled on a thin tooth pick.
Minh Ngọc translates our tour guide’s Vietnamese historic tales at the former residence of an ‘opium king’, Dinh thự họ Vương (H’Mong King Palace), Đồng Văn, Hà Giang in December 2015.
While EOS team members were carrying out experiments in the field, Minh Ngọc always warmly communicated with curious local people, which often made an important difference in the amount of support that we received. Above: Arndt, Minh Ngọc, Dương and Hướng pose with a local farming family after we received methane biogas in a Hanoi suburb for experiments in caves on Cát Bà island and near Đồng Văn in November 2015.
The EOS group and Mr. Ho’s family pose for a picture after finishing radon and thoron measurements inside an authentic mud house near Đồng Văn in December 2016. Despite the apparent poverty, the people in the area are neither destitute, nor hungry or unhappy. They were proud to invite us to their homes. Their friendliness is overwhelming.
Minh Ngọc shows a picture just taken with her cellphone to a grandma near Đồng Văn, Hà Giang Province in December 2016.
Any scientific fieldwork and experiments by foreign visitors in karst caves on the Đồng Văn plateau requires an official permit. Minh Ngọc helped the EOS group to establish personal contacts with local officials in Hà Giang Province, thus providing reliable logistic support for our research. Above: EOS team members and officers of the Management Board Đồng Văn Karst Plateau Geopark pose after visiting Lùng Khuý cave, Quản Bạ, Hà Giang (December 2015).
Above: Entry permit to the restricted area near the border to China issued for Minh Ngọc Schimmelmann in December 2016.
Minh Ngọc and Arndt in front of Sảng Tủng commune office after methane and radiation safety measurements in Rồng cave, Đồng Văn, Hà Giang (December 2015).
Arndt and Minh Ngọc after working in Nà Luông cave, Yên Minh, Hà Giang (December 2015).
Minh helped the EOS team collecting air in plastic bags for mesocosm experiments in Minh Châu cave, Cát Bà island, Hải Phòng (November, 2015) which proved the microbial oxidation of methane in the air of subterranean environments. Dr. Agnieszka Drobniak from Indiana University was taking notes.
Minh Ngọc Schimmelmann interviews a group of curious local students in an agriculturally used sinkhole next to Rồng Cave, Sảng Tủng commune to inquire about the general health of local inhabitants of mud houses (December 2016).

In March 2016, Arndt and Minh Ngọc joined the EOS team during field work in rural northern Vietnam where deforestation and poverty often necessitate human habitation in ‘mud houses’. We noticed that regional soil in walls and floors contains enough natural radioactivity to emit hazardous radon levels far exceeding EPA safety thresholds. Especially the radon-220 isotope with a short half-life of ca. 55 seconds poses a health hazard that cannot be mitigated by venting of room air. Radon-220 diffuses out of porous mud into room air. Human inhalation and a chain of radioactive decay reactions of radon and its metallic daughter products can induce lung cancer.

More than half a billion people worldwide live in dwellings that are partially constructed with earthen walls. The reason for Vietnamese mud house construction is poverty and the low price of construction. The situation may be different in other developing countries. The situation is again altogether different in developed countries like in Germany where the inhabitants of houses with earthen walls want to be “green” and may indeed treasure the ‘natural appearance’. We need to first generate awareness that a radiation safety problem exists when earthen walls emit radon isotopes.

Minh Ngọc and Arndt walked together along a stone road in a village, Đồng Văn, Hà Giang, December 2016.

In late 2016, Arndt and Minh Ngọc returned to Vietnam and joined our EOS team to visit an authentic ‘mud house’ in a village in Hà Giang Province close to the Chinese border. Despite the time-consuming travel from Hà Nội to Hà Giang and major problems with entry permits to the restricted border region, our group successfully completed three days and nights of radiation safety experiments in a mud house.

We developed and successfully tested a novel method to mitigate the exhalation of thoron into the room air in soil-built houses. The radioactivity in room air near walls (where people sleep at night) decreased from hazardous levels to below detection limit. Our method of mitigating the thoron radiation geohazard is affordable, sustainable, socially acceptable, non-toxic, and can be applied with partially recycled resources that are readily available in most developing countries.

The project is dear to the hearts of EOS members. Arndt and Minh Ngọc are convinced that we can help many people all over the world to live healthier lives.

The EOS group posed with a family who are living at a mountainous village at Bạch Đích commune, Yên Minh district, Hà Giang Province – near the border between Vietnam and China. The family was willing to allow the EOS group to perform experiments in their mud-built house in December 2016.
EOS members standing in front of newly built mud house in a Hanoi suburb in November 2017. The model mud-house is being used exclusively for experiments which mainly focus on: (1) developing recommendations for affordable and sensitive detection methods for radon and thoron in mud-built homes; (2) assessing the concentrations and distributions of thoron and radon in mud house air; (3) devising affordable, non-toxic and socially acceptable sealing of porous mud surfaces in homes to prevent exhalation of thoron and radon, and to improve public health.

Outreach to local communities in Hà Giang province

Minh Ngọc convinced the EOS group that we should help improve the lives of children in economically disadvantaged areas. While the group was planning science, Minh Ngọc busily searched for winter clothing and school supplies at wholesale prices in Hanoi. Outreach activities in mountain villages mainly targeted elementary schools serving primarily minority children in Hà Giang Province. Our outreach efforts were coordinated with regional and local governments and were assisted by the schools’ principals and teachers. This way we also established personal contacts and reliable logistic support for our research in the field.

Members of the EOS group donated clothes to students in a primary school in Sảng Tủng commune, Đồng Văn District, Hà Giang Province, several days before Christmas Day in December 2015.
Minh Ngọc Schimmelmann distributed winter clothing and school supplies for minority ethnic students in a primary school in Sảng Tủng commune, Đồng Văn District, Hà Giang Province (December 2015).
A minority ethnic student with donated winter clothing in a primary school in Sảng Tủng commune, Đồng Văn District, Hà Giang Province (December 2015).
EOS group members and collaborators donated clothes to students in a primary school in Mậu Duệ commune, Yên Minh district, Hà Giang Province, several days before Christmas Day in December 2015.
Minh Ngọc donated clothes to students in a primary school in Mậu Duệ commune, Yên Minh district, Hà Giang Province, several days before Christmas Day in December 2015.
The school’s principal (in pink jacket) invited Minh Ngọc to visit the school kitchen at Mậu Duệ commune, Yên Minh District, Hà Giang Province, December 2015.
Minh Ngọc Schimmelmann and Dương Nguyễn-Thùy donated stationery to students in a primary school in Sảng Tủng commune, Đồng Văn District, Hà Giang Province, several days before Christmas Day in December 2016.

Geosciences are improving the lives of people in Vietnam