Volcanic in origin, Indian Rock is the largest of a number of similar rhyolite rock formations in the vicinity, including the smaller rocks in the portion of the park on the east side of Indian Rock Ave. For example, only one block farther up the east side of Indian Rock Avenue is the  Mortar Rock Park, which has its own complex of granite outcroppings.
Volcanic in origin, Indian Rock is one of several rhyolite rock formations nearby, including smaller rocks on the east side of Indian Rock Avenue. For instance, just a block further up the east side of Indian Rock Avenue is Mortar Rock Park, which has its own granite outcroppings.