A food safety factory shutdown has Americans hunting for baby formula. Readying themselves for a covid-19 lockdown, Chinese in Beijing emptied store shelves. Emerging from lockdown, some in Shanghai are visiting well-provisioned markets. U.S.-China agricultural trade is booming, but many are still being left hungry. Food security, sustainability and safety remain issues.
Darby, "Structural evolution of the southwestern Daqing Shan, Yinshan Belt, Inner Mongolia, China," 1999
Brian Joseph Darby, M.S
The southwestern Daqing Shan lie $\sim$500 km west of Beijing along the northern edge of the North China craton. The southwestern Daqing Shan are part of the Yinshan belt, an east-west-trending, $\ge$1100 km-long zone of folding and thrusting mainly of Jura-Cretaceous age.
Detailed mapping, construction of numerous cross-sections, and analysis of relations between structures and stratigraphic units allow for the distinction of multiple deformational events in the southwestern Daqing Shan, which began in the Paleozoic. The tectonics of the southwestern Daqing Shan may be related to far-field effects of plate interaction. Late Jurassic contractional deformation in the southwestern Daqing Shan and elsewhere in the Yinshan belt is most likely an intraplate response to closure of the Mongolo-Okhotsk ocean 800-1000 km to the north, or possibly accretion of crustal blocks to the south along the Bangong suture.