I think the "geographical meaning" you suggest has to do with the context in which the line is used:
...we are in a basin. that is the
idea. down in the sand and the alleys,
this land punched-in, cuffed-out, divided,
held like a crucifix in a deathhand,
this land bought, resold, bought again and
sold again, the wars long over,
the Spaniards all the way back in Spain
down in the thimble again, and now
real estaters, subdividers, landlords, freeway
engineers arguing...
Buk is using "crucifix in a deathhand" as imagery for how people possess land and guard it fiercely, argue over it, etc. Crucifix in a deathhand could be viewed two ways:
1. Holding something dear in a death grip; or
2. Holding something that was god's will the white man shall have dominion over in a rigor-mortis-induced state of immobility. In other words, the concept of god giving the white man dominion over the land actually leads to an unsatisfied death rather than the success that so many associate with the accumulation of commodities, such as land.
That's my take, but I don't like to analyze this stuff. :aerb: