Combine water, sugar, and fresh rosemary in a pan and heat on high until boiling. Remove pan from heat, cover, and let rosemary steep for 30 minutes. Strain liquid, and store in a jar in the refrigerator, until ready to use.

Combine tequila, juices from tangerines, lemons, and limes, and rosemary simple syrup in a cocktail shaker or jar with ice, and shake until well combined.

Place ice in 4 margarita glasses, and divide shaken margarita mixture equally between the 4 glasses, then top off each glass with ~ 1/4 cup pomegranate juice, or until glass is full. Garnish with pomegranate arils and a sprig of fresh rosemary.