Thermal evolution of mafic granulites of Princess Elizabeth Land, East Antarctica

Evincing the presence of a trans‐Gondwanian mobile belt in the interior of the Princess Elizabeth Land, East Antarctica: insights from offshore detrital sediments, rock fragments, and monazite geochronology

“…30% fraction yielded 454 ± 24 Ma (near Pan‐African age) and the 70% fraction yielded 686.1 ± 17 Ma age representing a Tonian‐Cryogenian event (Figure 13c). ~700 Ma ages also correspond to the event reported from the coastal outcrop of PEL (e.g., Arora et al, 2020; Sadiq et al, 2021), though from different types of rocks. For further evaluation, age versus Ce, Th, and Y weight percentages of both types of monazites have been plotted (Figure 14a–c).…”

“…Declustering of the age data is carried out based on the probability graphs and two major groups are represented separately as shown in Figure 13a 13c). $700 Ma ages also correspond to the event reported from the coastal outcrop of PEL (e.g., Arora et al, 2020;Sadiq et al, 2021), though from different types of rocks. For further evaluation, age versus Ce, Th, and Y weight percentages of both types of (Linthout, 2007)…”

“…Although ages of ~1,100 to 500 Ma are observed in the detrital monazites, no Grenvillian age is estimated in texturally constrained monazites in the rock fragment (RF1) which makes the geochronological refinement of the terrain more complex. Pan‐African granulite metamorphism with relics of at least two older events have been widely reported from the Prydz Bay (~1,000 Ma: Zhao et al, 1992; Hensen & Zhou, 1995 and ~800 Ma: Arora et al, 2020; Mikhalsky et al, 2020; Sadiq et al, 2021) (Figure 15b). New emerging data from various mobile belts signify the presence of ~800 Ma events (e.g., Arora et al, 2020).…”

“…The Brattstrand Bluffs and the Larsemann Hills Block mainly comprises of granulite‐grade lithology which exhibits imprints of a Grenvillian (~1,000 Ma), a younger Neoproterozoic (700–800 Ma) as well as a Pan‐African orogeny (~500 Ma) (e.g., Carson, Fanning, & Wilson, 1996; Tong, Wilson, & Liu, 2002; Wang et al, 2008; Arora et al, 2020 and the references therein). This terrain preserves an older Tonian‐Cryogenian imprint partially modified by the Pan‐African tectonic activity (Arora et al, 2020; Sadiq et al, 2021). Towards ~140 km westwards, the major outcrops just adjacent to the Lambert graben belong to the Landing Bluff terrane that exposes the undeformed granites of the Pan‐African age.…”

Investigations on baseline levels for natural radioactivity in soils, rocks, and lakes of Larsemann Hills in East Antarctica

“…The Prydz Bay sector of East Antarctica has been shown as a terrain of Indian affinity by Boger (2011). Through recent metamorphic and geochronological data, high-grade Pan-African signatures (~ 500 Ma) have been indicated in both the Larsemann Hills-Prydz Bay of East Antarctica (Arora et al, 2020;Sadiq et al, 2021) as well as the Eastern Ghats Mobile Belt-Rengali Belt of India (Bose et al, 2016;Bose et al, 2021), confirming their shared history during Gondwana Amalgamation. Monazites reported from sectors of Indian shield such as the Southern granulite terrain (Santosh et al, 2003) and the Eastern Ghats Mobile Belt-Rengali domain (Bose et al, 2016) also define peak ages of ~ 500 Ma.…”