Figure 9.3 Palynostratigraphy of the El Kef locality, Tunisia (modified from Meon 1990). The Maastrichtian-Danian (K-T) boundary is between an unnamed foraminiferal zone (''non nommee') and the Globigerina eugubina foraminiferal zone ("Eugubina"). The area within the box showing palynomorph occurrences near the boundary is enlarged and rotated in Figure 9.4. Reprinted by permission of Elsevier.
10 Undulatisporites cf. undulapolus
11 Undulatisporites cf. concavus
13 Echinatisporis varispinosus
14 Echinatisporis cf. levidensis 16 Leptolepidites cf. tenuis
20 Verrucosisporites obscurilaesuratus
24 Cicatricosisporites neumanii
30 Corrugatisporites cf. toratus
38 Mecsekisporites sp.
41 Vadaszisporites cf. urkuticus
42 Vadaszisporites sp.
46 Gleicheniidites senonicus
55 Polypodiaceoisporites sp. 3
56 Segmentizonosporites sp. 59 Auracariacites australis 75 Magnolipollis sp. 2
78 Monosulcites cf. minutus
110 Retricolpites sp. 2
114 Tricolpites sp. cf. T. interruptiretis
140 Tricolporopollenites sp.
Figure 9.4 Detailed view of palynomorph occurrences near the K-T boundary at El Kef, Tunisia, enlarged from Figure 9.3 and rotated to horizontal (modified from Meon 1990).
volcanic flows in the world, as the cause of the K-T extinctions (e.g., Courtillot et al. 1988, 1990); see Section 11.4. Vast quantities of basaltic lava erupted in west-central India during an interval of a few million years around K-T boundary time. Unfortunately, the palynostratigraphic record of the uppermost Cretaceous and lowermost Paleogene interval in India lacks the resolution necessary to determine the position of the K-T boundary accurately.
Indigenous species of Aquilapollenites are present in the Upper Cretaceous in India (Baksi and Deb 1981, Nandi and Chattopadhyay 2002), but India is not considered to be within the Aquilapollenites Province. Herngreen et al. (1996) assigned India to the Palmae Province (see Figure 5.4). Paleocene assemblages show affinity with both the Palmae and Normapolles provinces, as discussed by
Herngreen et al. (1996). Based on their study of a "subcrop sequence'' in the Bengal Basin, Baksi and Deb (1981) stated that the K-T boundary is within the Jalangi Formation, but they published no details. Nandi (1990) reported on Upper Cretaceous palynostratigraphy of northeastern India, but the Senonian assemblages are imprecisely dated and of little or no value in determining the position of the K-T boundary. Dogra et al. (1994) conducted a palynostrati-graphic study of the Lameta Formation in Madhya Pradesh, central India, determining that it is Maastrichtian in age, but there is no discussion of the K-T boundary in that report.
Alt et al. (1988) suggested that an extraterrestrial impact might have initiated the extensive flows of basaltic lavas known as the Deccan Traps, which might have linked the two mechanisms as the cause of the K-T extinctions. This is unlikely, however, because the Deccan Trap flows are dated as having erupted between 67 and 63 Ma (Venkatesan et al. 1993,1996) and thus are only partly coincident with the K-T impact event at 65.5 Ma. Within the intertrappean sequence, Bhandari et al. (1995,1996) discovered an iridium anomaly between Flow III and Flow IV at Anjar, Kutch district, Gujarat, western India. The level is dated at 65.5 ± 0.7 and 65.4 ± 0.7 Ma. Bhandari et al. (1995) concluded that the impact event was the origin of the iridium and could not have triggered the Deccan volcanism because the lava flows had begun about a million and a half years earlier. On the basis of magnetic susceptibility and carbon isotope data, Hansen et al. (2001) disputed Bhandari et al.'s (1995) claim that their section was at the K-T boundary, but the Hansen et al. paper was contradicted by Shukla and Shukla (2002), who supported Bhandari et al.'s assessment on geochemical and geochronological grounds. Courtillot et al. (2000) also provided supporting data for the Anjar section.
Dogra et al. (2004) investigated the palynology of the locality studied by Bhandari et al. (1995) at Anjar, western India (locality 101 in Table 2.1 and Appendix). Dogra et al. determined that their assemblage, which included Aquilapollenites indicus and species assigned to the genus Proteacidites, is Maastrichtian in age. Singh et al. (2006) found that a palynomorph assemblage from mammal-bearing intertrappean beds in Andra Pradesh, southeastern India, is Maastrichtian in age. To date, no palynomorphs of Paleocene age have been recovered from the intertrappean sedimentary strata.
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