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Figure 2. Benthic foraminifers > 0.150 mm from the core ANP 1011: 1. Siphotextularia flintii; LMA-00357; 2. Massilina sp.; LM.A-00358; 3. Miliolinella sp.; LMA-00359; 4. Miliolinella subrotunda; LMA-00360; 5. Pyrgo quadrata; LMA-00361; 6. Pyrgo murrhina; LMA-00362; 7. Pyrgo aff. P. depressa; LMA-00363; 8. Pyrgo lucernula?; LMA-00364; 9. Pyrgo sp.; LMA-00365; 10. Quinqueloculina sp.; LMA-00366; 11. Sigmoilopsis schumbergeri; LMA-00367; 12. Triloculina sommeri; LMA-00368; 13. Triloculina sp.; LMA-00369; 14. Triloculinella sp.; LMA- 00370; 15. Spirillina decorata; LMA-00371; 16. Lagena hispidula; LMA-00372; 17. Lagena sp.; LMA-00373; 18. Lagena arquata; LMA-00374; 19. Lagenosolenia sp.; LMA-00375; 20. Nodosaria sp.; LMA-00376; 21. Amphicoryna sp.; LMA-00377; 22. Fissurina circularis; LMA-00378; 23. Bolivina interjuncta; LMA-00379; 24. Bolivina britanica; LMA-00380; 25. Bolivinita quadrilatera; LMA-00381; 26. Bolivinita sp.; LMA- 00382; 27. Globobulimina affinis; LMA-00383; 28. Globobulimina sp.; LMA-00384; 29. Uvigerina auberiana; LMA-00385; 30. Uvigerina peregrina; LMA-00386; 31. Uvigerina proboscidea; LMA-00387; 32. Uvigerina cf. U. hispida; LMA-00388; 33-34. Uvigerina spp.; LMA-00389. Scale bar =100 Um. and 42-39 cm with 16, 12, and 12 specimens, respectively. Only the genus Krithe represented by Krithe sinuosa Ciampo, 1986 and Krithe morkhoveni van den Bold, 1960, was abun- dant (75.5% of the total specimens). Juvenile individuals of this genus were also recovered, but identification at the spe- cies level was not feasible. The genera Argilloecia (8.1%) and Macromckenziea (5.81%) were classified as common, and the genera Bythoceratina, Cytheropteron, Ambocythere, and Rugocythereis as rare (1.16-3.48%). One species (1.16%), represented only by a juvenile specimen, was left in open Pteropod assemblages are mainly composed of taxa belong- ing to the families Lamacinidae (Heliconoides sp.), Atlantidae

Figure 2 Benthic foraminifers > 0.150 mm from the core ANP 1011: 1. Siphotextularia flintii; LMA-00357; 2. Massilina sp.; LM.A-00358; 3. Miliolinella sp.; LMA-00359; 4. Miliolinella subrotunda; LMA-00360; 5. Pyrgo quadrata; LMA-00361; 6. Pyrgo murrhina; LMA-00362; 7. Pyrgo aff. P. depressa; LMA-00363; 8. Pyrgo lucernula?; LMA-00364; 9. Pyrgo sp.; LMA-00365; 10. Quinqueloculina sp.; LMA-00366; 11. Sigmoilopsis schumbergeri; LMA-00367; 12. Triloculina sommeri; LMA-00368; 13. Triloculina sp.; LMA-00369; 14. Triloculinella sp.; LMA- 00370; 15. Spirillina decorata; LMA-00371; 16. Lagena hispidula; LMA-00372; 17. Lagena sp.; LMA-00373; 18. Lagena arquata; LMA-00374; 19. Lagenosolenia sp.; LMA-00375; 20. Nodosaria sp.; LMA-00376; 21. Amphicoryna sp.; LMA-00377; 22. Fissurina circularis; LMA-00378; 23. Bolivina interjuncta; LMA-00379; 24. Bolivina britanica; LMA-00380; 25. Bolivinita quadrilatera; LMA-00381; 26. Bolivinita sp.; LMA- 00382; 27. Globobulimina affinis; LMA-00383; 28. Globobulimina sp.; LMA-00384; 29. Uvigerina auberiana; LMA-00385; 30. Uvigerina peregrina; LMA-00386; 31. Uvigerina proboscidea; LMA-00387; 32. Uvigerina cf. U. hispida; LMA-00388; 33-34. Uvigerina spp.; LMA-00389. Scale bar =100 Um. and 42-39 cm with 16, 12, and 12 specimens, respectively. Only the genus Krithe represented by Krithe sinuosa Ciampo, 1986 and Krithe morkhoveni van den Bold, 1960, was abun- dant (75.5% of the total specimens). Juvenile individuals of this genus were also recovered, but identification at the spe- cies level was not feasible. The genera Argilloecia (8.1%) and Macromckenziea (5.81%) were classified as common, and the genera Bythoceratina, Cytheropteron, Ambocythere, and Rugocythereis as rare (1.16-3.48%). One species (1.16%), represented only by a juvenile specimen, was left in open Pteropod assemblages are mainly composed of taxa belong- ing to the families Lamacinidae (Heliconoides sp.), Atlantidae

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A total of five water masses exert influence in the study area, from the surface to the 2,125 m water depth where the core ANP 1011 was obtained: the Tropical Water (the surface water TW, 0-150 m), the South Atlantic Central Water (the pycno- clinic water SACW, 150-500 m), the Antarctic Intermediate Water (the intermediate water AAIW, 500-1,300 m), the Upper Circumpolar Water (the intermediate water UCPW, 500-1,300 m), and the North Atlantic Deep Water (the deep water NADW, 1,300-3,500 m) (Silveira et al. 2020). The TW presents the highest values of temperature and salinity of the water column (Emilsson 1961). The SACW, near its origin in the tropics, is characterized by the largest variation of temperature and salin- ity due to its position at the pycnocline level (Tomcezak and Godfrey 1994). The AAIW is characterized by the high values of oxygen and low salinity (Reid et al. 1977, Reid 1994). The UCPW presents lower oxygen concentrations and salinity and high dissolved nutrients associated with intense local silicate (Stramma and England 1999, Mémery et al.2000). The NADW is characterized by high values of oxygen and temperature, a secondary salinity maximum and low local levels of nutrients (Maamaatuaiahutapu et al. 1994). Moreover, this water mass is not corrosive to aragonite (Gerhardt et al. 2000). Surface waters of the Equatorial Atlantic Ocean are pres- ently influenced by the North Brazilian Current (NBC), the North Equatorial Sub-Current, the North Equatorial Counter- Current and the North Equatorial Current (Silveira et al. 2004). The NBC stems from the bifurcation of the southern branch of the South Equatorial Current when it reaches the Brazilian Continental Margin, between 10°S and 15°S (Schott et al. 2004, Talley 2011). According to Johns et al. (1998), the mobility of NBC coincides with changes in surface transport, Figure 1. Location map of the core ANP 1011 in the Ceara Basin showing the surface circulation in the Brazilian Equatorial Margin, the physiography of the study area, and current arrows are superimposed on their speed (Noucoucouk et al. 2021).
A total of five water masses exert influence in the study area, from the surface to the 2,125 m water depth where the core ANP 1011 was obtained: the Tropical Water (the surface water TW, 0-150 m), the South Atlantic Central Water (the pycno- clinic water SACW, 150-500 m), the Antarctic Intermediate Water (the intermediate water AAIW, 500-1,300 m), the Upper Circumpolar Water (the intermediate water UCPW, 500-1,300 m), and the North Atlantic Deep Water (the deep water NADW, 1,300-3,500 m) (Silveira et al. 2020). The TW presents the highest values of temperature and salinity of the water column (Emilsson 1961). The SACW, near its origin in the tropics, is characterized by the largest variation of temperature and salin- ity due to its position at the pycnocline level (Tomcezak and Godfrey 1994). The AAIW is characterized by the high values of oxygen and low salinity (Reid et al. 1977, Reid 1994). The UCPW presents lower oxygen concentrations and salinity and high dissolved nutrients associated with intense local silicate (Stramma and England 1999, Mémery et al.2000). The NADW is characterized by high values of oxygen and temperature, a secondary salinity maximum and low local levels of nutrients (Maamaatuaiahutapu et al. 1994). Moreover, this water mass is not corrosive to aragonite (Gerhardt et al. 2000). Surface waters of the Equatorial Atlantic Ocean are pres- ently influenced by the North Brazilian Current (NBC), the North Equatorial Sub-Current, the North Equatorial Counter- Current and the North Equatorial Current (Silveira et al. 2004). The NBC stems from the bifurcation of the southern branch of the South Equatorial Current when it reaches the Brazilian Continental Margin, between 10°S and 15°S (Schott et al. 2004, Talley 2011). According to Johns et al. (1998), the mobility of NBC coincides with changes in surface transport, Figure 1. Location map of the core ANP 1011 in the Ceara Basin showing the surface circulation in the Brazilian Equatorial Margin, the physiography of the study area, and current arrows are superimposed on their speed (Noucoucouk et al. 2021).
Figure 3. Benthic foraminifera and pteropods >0.150mm from the core ANP 1011: 1. Cassidulina sp.; LMA-00390; 2. Cassidulinoides sp.; LMA 00391; 3. Globocassidulina subglobosa; LMA-00392; 4. Globocassidulina sp.; LMA-00393; 5. Fursekoina sp.; LMA-00394; 6. Anomalinoide. sp.; LMA-00395; 7. Chilostomella globata; LMA-00396; 8a-b. Oridorsalis umbonatus; LMA-00397; 9a-b. Osangularia culter; LMA-00398 10. Cancris nuttalli; LMA-00399; 11. Valvulineria glabra; LMA-00400; 12a-b. Rosalina bradyi; LMA-00401; 13. Melonis barleeanum; LMA 00402; 14. Melonis pompilioides; LMA-00403; 15. Pullenia bulloides; LMA-00404; 16. Cibicides sp.; LMA-00405; 17a-b. Cibicides kullenbergi LMA-00406; 18. Cibicidoides lobatulus; LMA-00407; 19. Cibicidoides wuellerstorfi; LMA-00408; 20. Cibicidoides incrassatus; LMA-00409 21. Cibicidoides cicatricosus; LMA-00410; 22. Cibicidoides aff. C. bradyi; LMA-00411; 23. Cibicidoides aff. C. mundulus; LMA-00412; 24 Cibicidoides sp.; LMA-00413; 25. Lamacinidae (Heliconoides sp.); LMA-00414; 26. Atlantidae (Atlanta sp.); LMA-00415; 27. Cavoliniida (Creseis? sp.); LMA-00416. Scale bar = 100 Um. The foraminifera assemblages of the core ANP 1011 char- acterize a typical bathyal paleoenvironment, as indicated by The carbonate content analysis revealed values between 78.61 and 27.06% (Suppl. Mat.; Fig. 6). The highest values were observed in the middle (90-59 cm), decreasing toward the core top (6-0 cm). Concerning the organic matter content, the anal- yses revealed values between 0.9 and 2.3%, with an average of acterize a typical bathyal paleoenvironment, as indicated by yses revealed values between 0.9 and 2.3%, with an average of
Figure 3. Benthic foraminifera and pteropods >0.150mm from the core ANP 1011: 1. Cassidulina sp.; LMA-00390; 2. Cassidulinoides sp.; LMA 00391; 3. Globocassidulina subglobosa; LMA-00392; 4. Globocassidulina sp.; LMA-00393; 5. Fursekoina sp.; LMA-00394; 6. Anomalinoide. sp.; LMA-00395; 7. Chilostomella globata; LMA-00396; 8a-b. Oridorsalis umbonatus; LMA-00397; 9a-b. Osangularia culter; LMA-00398 10. Cancris nuttalli; LMA-00399; 11. Valvulineria glabra; LMA-00400; 12a-b. Rosalina bradyi; LMA-00401; 13. Melonis barleeanum; LMA 00402; 14. Melonis pompilioides; LMA-00403; 15. Pullenia bulloides; LMA-00404; 16. Cibicides sp.; LMA-00405; 17a-b. Cibicides kullenbergi LMA-00406; 18. Cibicidoides lobatulus; LMA-00407; 19. Cibicidoides wuellerstorfi; LMA-00408; 20. Cibicidoides incrassatus; LMA-00409 21. Cibicidoides cicatricosus; LMA-00410; 22. Cibicidoides aff. C. bradyi; LMA-00411; 23. Cibicidoides aff. C. mundulus; LMA-00412; 24 Cibicidoides sp.; LMA-00413; 25. Lamacinidae (Heliconoides sp.); LMA-00414; 26. Atlantidae (Atlanta sp.); LMA-00415; 27. Cavoliniida (Creseis? sp.); LMA-00416. Scale bar = 100 Um. The foraminifera assemblages of the core ANP 1011 char- acterize a typical bathyal paleoenvironment, as indicated by The carbonate content analysis revealed values between 78.61 and 27.06% (Suppl. Mat.; Fig. 6). The highest values were observed in the middle (90-59 cm), decreasing toward the core top (6-0 cm). Concerning the organic matter content, the anal- yses revealed values between 0.9 and 2.3%, with an average of acterize a typical bathyal paleoenvironment, as indicated by yses revealed values between 0.9 and 2.3%, with an average of
Figure 4. Bathyal ostracods > 0.150 mm from the core ANP 1011: 1. Macromckenziea sp.; LMA-00417; 1a. RV, lateral view; 1b. RV, internal view; lc. adductor scars detail; 2. Macropyxis bathyalensis; 2a. LMA-00418, RV, lateral view; 2b. LMA-005 13, LV, internal view; 2b. RV, internal view; 3. Argilloecia labri; LMA-00419; 3a. LV, lateral view; 3b. LY, internal view; 4. Argilloecia sp.; LMA-00420; 4a. LY, lateral view; 4b. LV, internal view; 5. Bythoceratina scaberrima; RV, lateral view; LMA-00421. 6. Cytheropteron sp.; RV, lateral view; LMA-00422; 7. Ambocythere cf. A. circumporus; LV, lateral view; LMA-00423; 8. Ambocythere sp. 1; RV, lateral view; LMA-00424; 9. Gen. et sp. indet.; RV, lateral view; LMA- 00425; 10. Rugocythereis sp.; LV, lateral view; LMA-00426; 11. Krithe sinuosa; LMA-00427; 11a. RV, lateral view; 11b. RV, internal view; 12. Krithe morkhoveni; LMA-00428; 12a. RV, lateral view; 12b. RV, internal view. LV: left valve; RV: right valve. Scale bar = 200 um. This environmental setting corresponds to Biozone Y (Fig. 6) and is characterized by the dominance of the epi- faunal taxa Cibicidoides, Miliolinella, Triloculina, Pyrgo, and Quinqueloculina. The higher abundance of epifaunal species in the sample 110-107 cm suggests an increase in phytode- tritus input and oxygenation (Caralp 1984, 1988, Lutze and Coulbourn 1984, Gupta and Thomas 2003). Cibicidoides wuel- lerstorfi and Pyrgo murrhina were relatively abundant in the core ANP 1011 during the Pleistocene, which suggests a cold and highly oxygenated scenario (Gupta and Satapathy 2000, Gupta and Thomas 2003). Cibicidoides wuellerstorfi characterizes cold environments with active currents, low-to-intermediate The linkage of foraminifera’s assemblage composition with environmental parameters, such as occurrence, microhabitats, cold environments with active currents, low-to-intermediate
Figure 4. Bathyal ostracods > 0.150 mm from the core ANP 1011: 1. Macromckenziea sp.; LMA-00417; 1a. RV, lateral view; 1b. RV, internal view; lc. adductor scars detail; 2. Macropyxis bathyalensis; 2a. LMA-00418, RV, lateral view; 2b. LMA-005 13, LV, internal view; 2b. RV, internal view; 3. Argilloecia labri; LMA-00419; 3a. LV, lateral view; 3b. LY, internal view; 4. Argilloecia sp.; LMA-00420; 4a. LY, lateral view; 4b. LV, internal view; 5. Bythoceratina scaberrima; RV, lateral view; LMA-00421. 6. Cytheropteron sp.; RV, lateral view; LMA-00422; 7. Ambocythere cf. A. circumporus; LV, lateral view; LMA-00423; 8. Ambocythere sp. 1; RV, lateral view; LMA-00424; 9. Gen. et sp. indet.; RV, lateral view; LMA- 00425; 10. Rugocythereis sp.; LV, lateral view; LMA-00426; 11. Krithe sinuosa; LMA-00427; 11a. RV, lateral view; 11b. RV, internal view; 12. Krithe morkhoveni; LMA-00428; 12a. RV, lateral view; 12b. RV, internal view. LV: left valve; RV: right valve. Scale bar = 200 um. This environmental setting corresponds to Biozone Y (Fig. 6) and is characterized by the dominance of the epi- faunal taxa Cibicidoides, Miliolinella, Triloculina, Pyrgo, and Quinqueloculina. The higher abundance of epifaunal species in the sample 110-107 cm suggests an increase in phytode- tritus input and oxygenation (Caralp 1984, 1988, Lutze and Coulbourn 1984, Gupta and Thomas 2003). Cibicidoides wuel- lerstorfi and Pyrgo murrhina were relatively abundant in the core ANP 1011 during the Pleistocene, which suggests a cold and highly oxygenated scenario (Gupta and Satapathy 2000, Gupta and Thomas 2003). Cibicidoides wuellerstorfi characterizes cold environments with active currents, low-to-intermediate The linkage of foraminifera’s assemblage composition with environmental parameters, such as occurrence, microhabitats, cold environments with active currents, low-to-intermediate
Species of Quinqueloculina are highly mobile in fine-grained sediments in both shallow (Severin et al. 1982) and deep Figure 5. Graphic representation of (A) the relative abundance (RA) of main genera and species of benthic foraminifera and (B) of the absolute abundance (AA) ostracods identified in core ANP 1011. in low organic carbon environments (Lutze and Coulbourn 1984, Gupta and Srinivasan 1996, Gupta and Thomas 2003, Murgese and De Deckker 2005).
Species of Quinqueloculina are highly mobile in fine-grained sediments in both shallow (Severin et al. 1982) and deep Figure 5. Graphic representation of (A) the relative abundance (RA) of main genera and species of benthic foraminifera and (B) of the absolute abundance (AA) ostracods identified in core ANP 1011. in low organic carbon environments (Lutze and Coulbourn 1984, Gupta and Srinivasan 1996, Gupta and Thomas 2003, Murgese and De Deckker 2005).
Figure 6. Integration and interpretation of data in the ANP 1011 core: calcium carbonate, organic material and organic carbon, absolute abundance (AA) of ostracods, pteropods and benthic foraminifera, relative abundance (RA) of agglutinated, porcelaneous and hyaline tests of benthic foraminifera, and relative abundance of infaunal and epifaunal foraminifera of the ANP 1011 core: (1) Quinqueloculina sp.; (2) Pyrgo murrhina; (3) Uvigerina proboscidea; (4, 13) Lamacinidae (Heliconoides sp.); (S, 11) Krithe sinuosa; (6) Uvigerina peregrina; (7) Uvigerina auberiana; (8) Melonis barleeanum, (9) Globocassidulina sp.; (10) Macromckenziea sp.; (12) Atlantidae (Atlanta sp.). High abundances of Melonis barleeanum in both the North (Thomas et al. 1995) and South Atlantic (Schmiedl and Mackensen 1997) characterize high productivity with sustained flow of organic matter. On the contrary, in the Indian Ocean, Melonis barleeanum indicates moderate organic flow with inter- mediate to high seasonality (Murgese and De Deckker 2005). mediate to high seasonality (Murgese and De Deckker 2005). This interval corresponds to Biozone Z (Fig. 6) and is characterized by environmental instability with a tendency to increase (predominance of uvigerinids) or decrease (predom- inance of cassidulinids) oxygenation. Oxygen concentration and nutrient are highly influential on infaunal assemblages’ composition (De Rijk et al. 1999, Jorissen et al. 2007). The increase in infaunal taxa (Uvigerina and Melonis) in the core ANP 1011 in the Pleistocene-Holocene transition indicates higher concentrations of organic carbon and nutrient and lower oxygenation (Miao and Thunell 1993, Gooday 1994, lower oxygenation (Miao and Thunell 1993, Gooday 1994,
Figure 6. Integration and interpretation of data in the ANP 1011 core: calcium carbonate, organic material and organic carbon, absolute abundance (AA) of ostracods, pteropods and benthic foraminifera, relative abundance (RA) of agglutinated, porcelaneous and hyaline tests of benthic foraminifera, and relative abundance of infaunal and epifaunal foraminifera of the ANP 1011 core: (1) Quinqueloculina sp.; (2) Pyrgo murrhina; (3) Uvigerina proboscidea; (4, 13) Lamacinidae (Heliconoides sp.); (S, 11) Krithe sinuosa; (6) Uvigerina peregrina; (7) Uvigerina auberiana; (8) Melonis barleeanum, (9) Globocassidulina sp.; (10) Macromckenziea sp.; (12) Atlantidae (Atlanta sp.). High abundances of Melonis barleeanum in both the North (Thomas et al. 1995) and South Atlantic (Schmiedl and Mackensen 1997) characterize high productivity with sustained flow of organic matter. On the contrary, in the Indian Ocean, Melonis barleeanum indicates moderate organic flow with inter- mediate to high seasonality (Murgese and De Deckker 2005). mediate to high seasonality (Murgese and De Deckker 2005). This interval corresponds to Biozone Z (Fig. 6) and is characterized by environmental instability with a tendency to increase (predominance of uvigerinids) or decrease (predom- inance of cassidulinids) oxygenation. Oxygen concentration and nutrient are highly influential on infaunal assemblages’ composition (De Rijk et al. 1999, Jorissen et al. 2007). The increase in infaunal taxa (Uvigerina and Melonis) in the core ANP 1011 in the Pleistocene-Holocene transition indicates higher concentrations of organic carbon and nutrient and lower oxygenation (Miao and Thunell 1993, Gooday 1994, lower oxygenation (Miao and Thunell 1993, Gooday 1994,
Table 1. Paleoecological inferences and microhabitat preferences of benthic foraminifera found in the core ANP 1011.
Table 1. Paleoecological inferences and microhabitat preferences of benthic foraminifera found in the core ANP 1011.
Related topics:
Pleistocene Holocene TransitionBrazilian Geology
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