[2] The Lachman Crags and Herbert Sound members, named after the areas in which they outcrop, are found in the northern part of James Ross Island.

Bioturbation is evident in tuff beds throughout the member due to the disruption of sediments by benthic life during the time of deposition.

The Rabot Member of the Santa Marta Formation is confined to the southeastern part of James Ross Island and dates back to the early to late Campanian.

Polychaete annelid worms such as Rotularia and gastropods such as the cerithiid sea snail Cerithium have also been discovered in beds within the formation.

Vertical spreite trace fossils have been found as part of fodinichnia dominated ichnocoenosis and were assigned to ichnogenre such as Paradictyodora.

[9] The close relation of T. antarcticus to other species of Taniwhasaurus found in New Zealand and Patagonia provides evidence for a Gondwanan endemism.

Although the formation is made up of only marine deposits, the bodies of these animals along with other debris may have frequently been washed out to sea to later sink to the bottom and be buried by sediment.

Leaves and fragments of plants are commonly found as fossils throughout the formation as well as large tree trunks in the lower members.

This is evidence of the forested environment that covered Antarctica during the Late Cretaceous due to the overall warmer global temperature and milder climate.