133845.pdf

(^142) DAVID J. CANTRILL & IMOGEN POOLE
Fig, 1. View of Gondwana break-up for selected times in the Cretaceous, (A) Valanginian (135 Ma BP),
illustrating the close proximity of Africa and India to the rest of Gondwana, (B) Albian (105 Ma BP). Note
that India and South Africa have separated from the rest of Gondwana. (C) Santonian (84 Ma BP) showing
extensive separation between India, Africa and the rest of Gondwana. Australia is beginning to rift from
Antarctica along the southern margin. (D) Maastrichtian (68 Ma BP). New Zealand and Lord Howe rise are
rifting from the eastern margin of Gondwana. Note the continued maintenance of connections between
South America and east Gondwana (Australia, Antarctica, New Zealand), Latitude intervals are 30": dashed
black line represents palaeopolar circle. Reconstructions provided by R. A. Livermore. British Antarctic
Survey.
developing a framework that reconstructs the
position of these fragments through time is
critical for understanding terrestrial connections
between various landmasses and subsequent
vicariant events.
The same is also true for other regions of
Gondwana; for example, large uncertainties
exist in our knowledge of the separation of India
from Antarctica, due to a lack of seafloor data
and age constraints on magnetic anomalies
along the Antarctic margin. The development of
marine conditions in present-day eastern Indian
sedimentary basins suggests that the separation
of India was diachronous from west to east
(Truswell et ai 1999). However, reconstructions
based on seafloor magnetic anomalies indicate