Properties of 109-1010 GeV extensive air showers at core distances between 100 and 3000 m

An examination is made of some properties of 109-1010 GeV extensive air showers, such as the electron and the muon lateral distribution, the ratio of muon to electron density, the shower front structure and the transient effects in a scintillator, with the new Akeno 20 km2 giant air showers array at core distances between 100 and 3000 m. At large core distances the lateral distributions of both electrons and muons become steeper than extrapolations of the formulae so far reported. (author)