Higher silica content means higher viscosity. But lower temperatures and low gas content mean higher viscosity. Hence, lower viscosity and low gas content mean higher temperature of magma.
The achievements of the Tang and Song Dynasties include "the invention of gunpowder and the growth of Confucianism".
The Song dynasty (960-1279) takes after the Tang (618-906) and the two together constitute what is regularly called "China's Golden Age."
The utilization of paper cash, the presentation of tea drinking, and the innovations of gun powder, the compass, and printing all happen under the Song. (The way that the tradition traverses the year 1000 may make it simpler for students to find these advancements in time.)
Aquaculture - growing of plants or animals in freshwater or marine ecosystems
Aquifers - underground source of water
Conservation - responsible use and management of natural resources
Overfishing - removing fish from an area at a rate faster than the fish can replace themselves
