The copper archer type may be the variety found in Merv regions, and the Merv-Herat is about the only place where they could be assigned. Sanabares, like the Gondophares group, minted coins in the 'debased area' which include imitation coinage of Hermaios from the Kabul Valley, the Gandhara coinage (after Azilises), and southern Arachosia. (Sanabares and the Gondophares Dynasty - K. WALTON DOBBINS)
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What does "debased area" mean?
This is fairly dense academic writing, and a full answer would probably require reading other things the author has published to see if they have defined 'debased area' more clearly in previous works, however:
I believe "debased area" here is a reference to a specific, historical region where debased coins were produced. A debased coin is one which has its value reduced, often by reducing the amount of precious metal it contains.
Sanabares was a king, and during his reign coins were minted (produced) in this area, just as they were during the rule of the Gondophares dynasty.
These "debased" coins include imitations of:
(coins of) Hermaios from the Kabul Valley
the Gandhara coinage (after Azilises)
(coins of) southern Arachosia
Why "debased area" rather than specifying a place like "the Merv-Herat"? Possibly because the precise location or correct name is not known, only that there was a common location where these imitation coins were produced.
