Guyana is high country, mountainous, and used to the torrential rainstorms that countries near the equator and near the ocean can receive on a regular basis. There are no active volcanoes nearby, the plate stable and unlikely to shatter. However, the very sharp ravines rising up into the mountains will present a danger during the shift itself. Water in the Caribbean, which will first empty during rotation stoppage when the water rushes to the poles and then refill with a sloshing rush as it attempts to return to the new equator, will rush up into the ravines with a tidal bore that will astonish anyone seeking refuse from high winds in the ravines. After the shift, Guyana will find itself in a more temperate climate, with many tropical plants that require high sunlight intensity suffering. Even in a lush country, temperate and with a peoples used to foraging, there will be a lack of food. Survivors from the cities, who can no longer import the foods they are accustomed to, will stumble about in the jungle, causing conflicts with native peoples and ultimately starving to death.
Liquifaction is primarily cause by water in the soil, not by the presence of sand. Sand is of course loose soil but unless water logged will not act like quicksand in this regard. Clay soil is rather solid, even when wet, so those heading to the hills would be advised to seek hills where the clay soil is predominant.
ZetaTalk July, 2010