Complex sentence: Bronze age excavations since 1965 covering, among others, the site at Altyndepe by Masson; and excavations by G. N. Lisitsyna to investigate the pre-historic economies and irrigation systems; the Merv Oasis had also been extensively explored by an American team in 1904.
Split into simpler sentences: Bronze age excavations since 1965 covering, among others, the site at Altyndepe by Masson; and excavations by G. N. Lisitsyna to investigate the pre-historic economies and irrigation systems. The Merv Oasis had also been extensively explored by an American team in 1904.