Sedimentology and Palynostratigraphy of a Pliocene

Journal of South American Earth Sciences 79 (2017) 215e229

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Journal of South American Earth Sciences

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Sedimentology and Palynostratigraphy of a Pliocene-Pleistocene (Piacenzian to Gelasian) deposit in the lower Negro River: Implications for the establishment of large rivers in Central Amazonia

* Emílio Alberto Amaral Soares a, Carlos D'Apolito b, c, , Carlos Jaramillo c, Guy Harrington b, Mario Vicente Caputo d,Rogerio Oliveira Barbosa a, Eneas Bonora dos Santos a, Rodolfo Dino e, Alexandra Dias Gonçalves a a Departamento de Geociências, Universidade Federal do Amazonas, Av. General. Rodrigo O. J. Ramos, 6200, CEP: 69.077-000, Manaus, AM, Brazil b Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK c Smithsonian Tropical Research Institute, Balboa, Ancon, Panama d Faculdade de Geologia, Universidade Federal do Para, Rua Augusto Corrêa 1, Guama, 66075-110 Belem, PA, Brazil e Petrobras/Cenpes/PDEDS/BTA, Departamento de Estratigrafia/Paleontologia, Universidade Estadual do Rio de Janeiro, RJ, Brazil article info abstract

Article history: The Amazonas fluvial system originates in the Andes and runs ca. 6700 km to the Atlantic Ocean, having Received 18 November 2016 as the main affluent the Negro River (second largest in water volume). The Amazonas transcontinental Received in revised form system has been dated to the late Miocene, but the timing of origin and evolutionary processes of its 10 August 2017 tributaries are still poorly understood. Negro River alluvial deposits have been dated to the middle to late Accepted 10 August 2017 Pleistocene. Recently, we studied a number of boreholes drilled for the building of a bridge at the lower Available online 14 August 2017 course of the Negro River. A thin (centimetric) sedimentary deposit was found, laterally continuous for about 1800 m, unconformably overlaying middle Miocene strata and unconformably overlain by younger Keywords: Amazon Basin Quaternary deposits. This deposit consists predominantly of brownish-gray sandstones cemented by Negro River siderite and with subordinate mudstone and conglomerate beds. Palynological, granulometric, textural Alter do Chao~ Formation and mineralogical data suggest that the initial Negro River aggradation took place in the deep incised Siderite valley under anoxic conditions and subsequently along the floodplain, with efficient transport of mixed Pliocene origin particles (Andean and Amazonic). Angiosperm leaves, wood and pollen are indicative of a tropical Pleistocene continental palaeoenvironment. A well preserved palynoflora that includes Alnipollenites verus, Grims- dalea magnaclavata and Paleosantalaceaepites cingulatus suggests a late Pliocene to early Pleistocene (Piacenzian to Gelasian) age for this unit, which was an age yet unrecorded in the Amazon Basin. These results indicate that by the late Pliocene-early Pleistocene, large scale river activity was occurring in Central Amazonia linking this region with the Andean headwaters, and therefore incompatible with Central Amazonia barriers like the Purus arch. © 2017 Elsevier Ltd. All rights reserved.

1. Introduction 2005; Latrubesse, 2008). The geological history of this system has been intensely debated in the literature, with a focus on the The Amazon drainage system is the largest on Earth and timing of transcontinentality (Figueiredo et al., 2009; Shephard supports an outstanding fauna and ﬂora diversity (Silva et al., et al., 2010; Latrubesse et al., 2010; Gorini et al., 2013; Horbe

* Corresponding author. E-mail addresses: [email protected] (E.A.A. Soares), [email protected] (C. D'Apolito), [email protected] (C. Jaramillo), [email protected] (G. Harrington), [email protected] (M.V. Caputo), [email protected] (R.O. Barbosa), [email protected] (E. Bonora dos Santos), dino@petrobras. com.br (R. Dino), [email protected] (A.D. Gonçalves). http://dx.doi.org/10.1016/j.jsames.2017.08.008 0895-9811/© 2017 Elsevier Ltd. All rights reserved. 216 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 et al., 2013; Sacek, 2014; Rossetti et al., 2015; Caputo and Soares, been dated to the Eocene-middle Miocene (Caputo, 2011; Soares 2016; Hoorn et al., 2017). Compelling evidence shows that An- et al., 2010, 2015, 2016; Dino et al., 2012; Caputo and Soares, dean sediments started reaching the mouth of the Amazon in the 2016), and where most rivers and alluvial deposits are uncon- late Miocene (~9 Ma, million years) (Hoorn et al., 2017), and by formably installed. Mapping of the upper unit of the Alter do the late Pliocene to early Quaternary a modern-like geography Chao~ Formation (informally termed Novo Remanso) shows its was attained (Figueiredo et al., 2009; Latrubesse et al., 2010; extension in Central Amazonia for ~300 km from Manacapuru Hoorn et al., 2010, 2017; Caputo and Soares, 2016). The origins to east of Itacoatiara (Dino et al., 2012; Soares et al., 2015) of individual Amazon River tributaries, however, is less under- (Fig. 1). stood but of crucial importance - these rivers archive information The Iça Formation covers thousands of kilometers in the Sol- on sedimentation styles, channel migration and ultimately on imoes~ Basin (Fig. 1) and rests unconformably on the Miocene- paleoenvironments and paleoclimate (e.g., Latrubesse and Pliocene Solimoes~ Formation (Maia et al., 1977; Nogueira et al., Franzinelli, 2005; Rossetti et al., 2014, 2015; Cremon et al., 2013). It is composed primarily of sandstone beds and subordi- 2016; Sant'Anna et al., 2017), which in turn are pivotal for un- nated siltstone, mudstone and conglomerate strata, and was derstanding the distribution of environments and organisms deposited in the middle to Upper Pleistocene (Rossetti et al., 2015). living in them across the continental scale Amazon biome. One In part, the age of this formation can be correlated with the ages of key fact, for instance, is how major rivers in Amazonia act as the Amazon River terraces, obtained by radiocarbon and lumines- barriers for animal groups and trigger diversification (Ayres and cence methods (see Introduction). Clutton-Brock, 1992; Ribas et al., 2009, 2012; d'Horta et al., 2013; Ferreira et al., 2017). Therefore, knowledge on age and 2. Materials and methods processes of river channels can have a direct link to biodiversity. In Amazonia, dating fluvial events has been a challenge owing We studied drilled sediments obtained from the Negro River to limited rock exposure and preservation (due to prevailing Bridge construction that took place between 2007 and 2011. incision and erosion), as well as the low range of the radiocarbon Sample recovery was achieved with a rotary drill and the unre- method and poor fossil preservation. Recently, optically stimu- covered parts with percussion drill. Basic lithological information lated luminescence (OSL) dating has been successfully applied was generated from 15 mixed bore holes with depths around 70 m and extended some chronologies. Maximum ages from ~240,000 in the central part of the Negro River's channel, spread along years have been reported for fluvial sands in the main courses of 1800 m and oriented in a NE-SW direction (Fig. 1). Analyses to ~ the Solimoes-Amazonas and Negro Rivers (Soares et al., 2010; generate sedimentological, stratigraphic, palynological and Fiore et al., 2014; Gonçalves et al., 2016; Sant'Anna et al., 2017) mineralogical data were performed on available samples recov- near Manaus in Central Amazonia. Similarly, ages varying from ered from three drill holes (Figs. 1 and 2). Samples analyzed here ~220,000 to 250,000 years were found in southwestern and are from cores that were described focusing on lithology, gran- northern Amazonian drainages, respectively (Rossetti et al., 2015; ulometry, sedimentary structures, fossil content and geological Cremon et al., 2016). Altogether, these chronologies point to an contact between units. Absence of geological information in the active fluvial regime in vast areas of the Amazon basin associated percussion drilling parts of the sections partially hampered the with deposition of the Iça Formation and diverse fluvial terraces elaboration of complete stratigraphic columns. during the Middle and Upper Pleistocene. The stratigraphic placement of the studied unit as well as its The Negro River, the main affluent of the Amazon drainage, with regional correlation was based on contact relations and petro- the second highest water volume, has been dated to the Middle graphic (thin sections and mineral identification), palynological Pleniglacial (65e25 ka) in its upper reach (Latrubesse and and mineralogical (x-ray diffraction) data. However, the frag- Franzinelli, 2005) and to ~45e65 ka in its lowers course (Soares mented aspect of the drilled unit hampered a precise measurement et al., 2010; Sant'Anna et al., 2017) at the confluence between the of thickness. ~ Solimoes-Amazons and Negro Rivers. The Upper Pleistocene evo- Samples were disaggregated using porcelain mortars and pistils lution of this river is marked by the combination of climatic and and then washed and separated into very fine (0.062e0.125 mm) tectonic forcing that led to the current anabranching morphology and fine (0.125e0.250 mm) sand intervals. The heavy mineral re- and the formation of sizable fluvial archipelagos (Latrubesse and covery was done with heavy liquid separation (bromoform, 2.89 g/ Franzinelli, 2002, 2005; Franzinelli and Igreja, 2002; Almeida- cm3) and grains were mounted on a slide using Canada balsam. Filho and Miranda, 2007). Here, we take advantage of a recently Sedimentological and petrographic analyses were done at the built bridge on the Negro River's lower course to study drilled Sedimentology and Microscopy laboratories of DEGEO-UFAM sediments of a paleochannel. We describe, date and characterize (Federal University of Amazonas). Thin sections and x-ray diffrac- these sediments within a regional stratigraphical and bio- tions were performed at the Thin Section Laboratory of the stratigraphical framework, thus aiming to reconstruct past fluvial Geological Survey of Brazil (CPRM-Manaus). For the x-ray diffrac- activity. tion we used a diffractometer X'PERT PRO MPD -PW 3040/60, Panalytical. 1.1. Geological context Pollen samples were processed following conventional methods (Wood et al., 1996) that consist of digestion of ca. 10 g of The stratigraphy of post-Paleozoic strata in the Amazonas sediment in hydrochloridric acid for 12 h (for carbonate extrac- Basin (Fig. 1) distinguishes records of the Cretaceous (Jazida da tion), then digestion in hydrofluoric acid for at least 24 h (for Fazendinha Formation), Cenozoic (Alter do Chao~ and Solimoes~ silicate extraction). Neutralization with water and decanting Formations) and Pleistocene (Iça Formation) (Daemon, 1975; were used after each acid digestion step. The dissolved mineral Dino et al., 1999; Caputo, 2011; Caputo and Soares, 2016). In portion was later sieved in 250 mmand10mm meshes for elim- central Amazonia, a significant extent of the rock cover is ination of coarser portions. The fraction <10 mm was then dis- composed of the Alter do Chao~ Formation red beds, which have aggregated in an ultrasonic bath and the less dense organic E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 217

Fig. 1. A) Map of South America with Amazonas state highlighted in northern Brazil. B) Map with river locations and towns between Manacapuru and Itacoatiara; C) geology around the conﬂuence of Negro and Solimoes~ Rivers and bathymetric proﬁle D-D0 with location of boreholes. Fig. 2. Column sections of three boreholes along the Negro River channel (D-D0), showing stratigraphy of Neogene, late Pliocene-early Pleistocene and Late Pleistocene-Holocene sedimentary units. Insets A and B show leaf and wood fossils, inset C shows the late Pliocene-early Pleistocene-Neogene contact (dotted line). E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 219

Fig. 3. Photomicrographs of sandstone thin section. A) Poorly selected sandstone with sub-angular to rounded Quartz grains (Qz) exhibiting two modes (in plane polarized light PPL). B) and C) are rock fragments (Fr) and Quartz, poorly sorted, surrounded by siderite cement (Ci) (in PPL). D) shows cement (Ci) constituted of rhombohedral crystals and microcrystalline crystals of siderite around quartz grains (in PPL and crossed polarized light XPL). E) shows irregular porosity (Pr), and F) shows white mica plaque (Mi) (in PPL).

matter portion recovered. This residue was cleaned in an ultra- The primary composition of the studied unit in cores F1, F2, sonic bath for a few seconds and concentrated in a centrifuge. and F14 (Fig. 2) includes siliciclastic constituents of arenite and Slides were then mounted with polyvinyl alcohol and sealed with subordinate pelite and conglomerate beds with a dark gray and Canada balsam. Analyses were performed along an optical mi- whitish color. The arenite is massive in aspect, moderate to croscope Zeiss Axioskop 40 and photomicrographs taken in poorly-sorted and fine- to very coarse-grained (Fig. 3). Locally 1000 magnification with a Canon EOS-500D. Laboratory pro- the arenites are conglomeratic, with granules and small, scat- cessing was done in Paleoflora Ltda., Colombia, and pollen ana- tered quartz pebbles (up to 1 cm). It is primarily formed by lyses performed at the Earth Sciences department, University of quartz, feldspar and rock fragments, sub-angular to rounded, Birmingham, UK. Identification of palynomorphs followed the with high to low roundness. Many of the grains are fractured, online database of Jaramillo and Rueda (2016), which contains with corroded edges and imbrications in some places. Quartz updated taxonomic information on palynology publications of grains are predominantly monocrystalline and rarely poly- Cretaceous-Cenozoic from northern South America. crystalline. The most common type of feldspar is microcline, followed by plagioclase, which is mostly altered into clay- minerals, epidote and carbonate. Rock fragments (igneous, 3. Results sedimentary and metamorphic) are in lower proportions. As accessory grains there is muscovite, dispersed and without any 3.1. Stratigraphic, sedimentological (textural) and preferred orientation, and microcrystalline quartz (silex). Heavy palaeoenvironmental analyses mineral grains, including unstable and ultrastable assemblages, are common such as zircon, tourmaline, rutile, kyanite, silli- The studied unit is very thin (estimated at 10e30 cm), ex- manite, apatite, topaz, garnet, hornblende and opaques (Fig. 4). hibits a sharp, irregular and erosive lower contact with the un- In general, an iron carbonate cement of a brown-red color is derlying Neogene substrate and an abrupt upper contact with present. It displays isochromatic rhombohedral (0.043 mm) and unconsolidated sediments of the Negro River Valley (Fig. 2). The microcrystalline (0.038 mm) crystals, uniaxial, with high bire- substrate is formed of pelitic intercalations (siltstones and fringence and cleavage, characterized by x-ray diffraction as claystones) and red and whitish sandstone beds, which can be siderite (Fig. 5). associated to fluvial deposits. Following the regional strati- The mechanic compaction in arenites is limited, as evidenced graphic context, the substrate belongs to the uppermost part of by fracturing of rigid grains and loose packing due to the pre- the Alter do Chao~ Formation of Eocene-middle Miocene age dominance of floating and point to point contact grains (Fig. 4-B, (Caputo, 2011; Caputo and Soares, 2016). The top unit of the Rio C, D and E). This demonstrates that the unit underwent shallow Negro Valley filling, with a thickness of nearly 30 m is formed of burial (<500 m). Inter and intragranular pores of irregular dis- intercalations of sand and mud (silt and clay) possibly associated tribution were observed in the arenite, allowing us to infer to channel bars of this river. Despite not having been dated, intrastratal dissolution. Fragmented wood and leaves were these sediments can be associated with Late Pleistocene and found in these arenites, with leaves being more abundant, and Holocene bars dated along the Solimoes~ and Amazonas rivers ranging from 2.1 to 7.5 cm in length. Their morphological (Gonçalves et al., 2016). 220 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229

Fig. 4. Heavy mineral grains: (A) Zircon (rounded to angular); (B) Turmaline; (C) Sillimanite; (D) Garnet; (E) Rutile; (F) Kyanite; (G) Hornblende; (H) Apatite and (I) opaque.

characteristics of blade (venation, symmetry, shape of the apex Caminha et al., 2010 and Stephanocolpites evansii Müller et al., and base) indicate that they belong to the Magnoliopsid class 1987. The assemblage includes also reworked Cretaceous paly- (Cronquist, 1981) of dicot angiosperms. Some of these fossils are nomorphs (Afropollis jardinus, Classopollis classoides, Cretacaeipor- well preserved and probably only fragmented due to mechanical ites polygonalis, Equisetosporites sp.), Neogene palynomorphs drilling. (Psilabrevitricolporites devriesii, Crassoretitriletes vanraadshooveni, Pelitic facies have planar-parallel lamination and conglomerates Foveotriletes ornatus), and a possible Late Palaeozoic spore genus are massive and made of centimetric (1e5 cm) sandstone with (Waltzispora sp.). reddish-whitish pelitic clasts, probably reworked from the underlying Neogene beds and involved in a sandy matrix. 4. Discussion

3.2. Palynology 4.1. Age

Samples analyzed for palynomorphs were productive, with a The ﬁrst appearance datum of Alnipollenites verus is widely rich palynological assemblage (Table A1, Fig. A1-A3), including recognized as a marker of the ﬁnal stage of the Pliocene and/or Alnipollenites verus (Potonie, 1931) ex Potonie 1934, Grimsdalea beginning of the Pleistocene in South America (Lorente, 1986; magnaclavata Germeraad et al., 1968 and Palaeosantalaceaepites Müller et al., 1987; Hooghiemstra, 1989). This taxon is found cingulatus Jaramillo et al., 2011. Other important taxa include in the Andes, Venezuela and other Caribbean basins, but is rare Bombacacidites ciriloensis Müller et al., 1987, Echitricolporites on the Amazon plains. In central Amazonia, the only occurrence mcneillyi Germeraad et al., 1968, Fenestrites spinosus Van Der of A. verus is in the Iça Formation (Pleistocene) in the region of Hammen, 1956, Cichoreacidites longispinosus (Lorente, 1986) Silva- Coari, west of Manaus (Nogueira et al., 2013). The palynological E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 221

Peaks -> CPS (x 1000) 01020304050

10 20 30 40 50 60 70 Position[*2Theta] (Copper (Cu))

Peak list

00-046-1045; Quartz syn; Si O2; Silicon Oxide

00-029-0696; Siderite; Fe C O3; Iron Carbonate

00-004-0551; Rutile; Ti O2; Titanium Oxide

Fig. 5. X-ray diffractogram of sample from borehole F-10 (location in Fig. 1), showing peaks of Quartz, Siderite and Rutile.

(1986) for Venezuela proposed the Zone IX Alnipollenites, subzone Alnipollenites/Grimsdalea, where G. magnaclavata and A. verus co-occur. This subzone was dated as early Pleistocene by Lorente although the subzone did not have a strong chronostratigraphic control. The subzone lays within the nanno- plankton zones NN12 to NN15 (Lorente, 1986), that ranges from the latest Miocene to the late Pliocene (5.5e3.6 Ma) (Hilgen et al., 2012). Pocknall et al. (2001) found that A. verus and G. magnaclavata co-occur in eastern Venezuela in the lower part of the planktonic foraminiferal zone N22 (Fig. 6) dated as ~1.9 to 1.0 Ma, middle Pleistocene (Hilgen et al., 2012). A recent study by Hoorn et al. (2017) of the pollen record in the Amazon Fan, found the last occurrence of G. magnaclavata to be within the middle part of the nannofossil zone NN19, dated as ~1.5 Ma (middle Pleistocene). This same study reported P. cingulatus Last Appearance Datum (LAD) to be at the onset of nannofossil zone NN16, dated as ~3.5 Ma, and in close agreement with the LAD proposed by Jaramillo et al. (2011) of ~3.7 Ma in the Llanos Basin. Hoorn et al. (2017) did not report A. verus in the assemblage. Fig. 6. Pollen zones and sub-zones proposed by Lorente (1986) for northern South America and comparison with stratigraphic ranges of A. verus, G. magnaclavata and Overall, the co-occurrence of A. verus, G. magnaclavata and P. cingulatus as proposed by Pocknall et al. (2001), Jaramillo et al. (2011) and Hoorn P. cingulatus suggest an age ranging between the late Pliocene (base et al. (2017) from Venezuela, Colombian Llanos and Foz do Amazonas, respectively. of nannofossil zone NN16, ~3.6) to early Pleistocene (base of nan- Zones T-17 and T-18 refer to the Llanos pollen zonation of Jaramillo et al. (2011). nofossil zone NN19, ~1.9 Ma) (Fig. 6).

4.2. Comparison with regional palynostratigraphic data zonation of Jaramillo et al. (2011) indicates the extinction of G. magnaclavata and of P. cingulatus in the Llanos Basin of There have not been reports of A. verus and G. magnaclavata co- Colombia within palynological zone T-18 (Plio-Pleistocene), and occurring in the Amazon Basin. There are reports of occurring at ~3.4 and ~3.7 Ma respectively (Fig. 6). The range of G. magnaclavata in older units (e.g. Dino et al., 2012), and A. verus in A. verus was not included in their work. The zonation of Lorente younger ones (Iça Formation, Nogueira et al., 2013), but never both 222 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 taxa have been found together. P. cingulatus is only reported in the sedimentation mode could have been developed in bars related Miocene deposits of the Solimoes~ Formation in the Solimoes~ Basin to post-Miocene fluvial dynamics established in the basin. (Leite et al., 2016) or up to ~3.5 Ma at the Foz do Amazonas Basin Despite a lack of characteristic sedimentary structures and the (Hoorn et al., 2017). Alnus is also a common presence in late reduced occurrence (what hampers a facies analysis) of the Pleistocene and Holocene sediments in central Amazonia (Absy, siderite rich unit, this interpretation is supported by the strati- 1979; Feitosa et al., 2015; Sa et al., 2016). This suggests that sedi- graphic position of this deposit in the section. It is situated be- ments of late Pliocene to early Pleistocene age (~3.6e1.9 Ma) are tween the Eocene-middle Miocene fluvial strata (Alter do Chao~ absent in most of the basin. Formation) and late Pleistocene-Holocene bars of the Negro The stratigraphic positioning established for the deep valley River. In addition, textural data of subangular to rounded, poorly unit (late Pliocene to early Pleistocene), pre-dates the sedimen- sorted arenite grains also support the palaeoenvironmental tary deposits of the Iça Formation. The Iça Formation is consti- interpretation above. The rather disperse granulometric mode is tuted of fluvial arenites and pelites, and presents a wide coherent with the proposed fluvial environment, which, accord- distribution in the western Amazon region (Solimoes~ Basin) (Reis ing to Folk (1974) tends to have moderate to low sorting effi- et al., 2006; CPRM, 2010; Caputo and Soares, 2016). This For- ciency with commonly different sized grains. Its massive aspect mation was initially defined by Maia et al. (1977) with an inferred and poor sorting of grains suggest a relatively rapid sedimenta- Pleistocene age and more recently refined by Rossetti et al. (2015) tion rate with moderate to high energy carrying sediments as with OSL ages as middle to late Pleistocene. A correlation of the bedload, consistent with deposition on the inside portions of present unit with the work of Nogueira et al. (2013) is precarious river channels, leaving lag deposits, as suggested by Miall (1992) due to lack of more precise biostratigraphic information. The and Collinson (1996). The suite roundness/sphericity suggests section studied by Nogueira et al. (2013) in the region of Coari, various source rocks, either proximal or distal to the depositional east of the Purus arch (Fig. 1), contains the topmost Solimoes~ site. The continental environment is likewise confirmed by Formation (late Miocene e Pliocene) unconformably overlain by palynomorphs and angiosperm macrofossils found within the the Iça Formation. An age for the unconformity between these sandy bar deposits. The good shape of these macrofossils sug- two formations has not been given but must occur between the gests short transport, indicating that fluvial bars underwent mid-late Pliocene up to the early Pleistocene, thus likely being an phytostabilisation and plants were rapidly buried in a probable age correlate to the new unit here described. More data are autochthonous accumulation. needed to properly constrain this age correlation. The new unit's environment of deposition has similarities with that of the Alter do Chao~ Formation, which presents facies of fl 4.3. Palaeoenvironment and palynomorph transport channel, point bar, oodplain, and crevasse splay characteristic of meandering fluvial systems. Sandy facies is composed of angular fi The palynological assemblage (Table A1) indicates tropical for- to sub-angular, ne- to coarse-grained and poorly selected are- est conditions, with an environment of fluvial plains indicated by nite (with dispersed granules) (Dino et al., 2012; Soares et al., the high abundance of fern spores (Laevigatosporites, Poly- 2015). podiisporites, Psilatriletes) as well as palm pollen grains (Maur- The main active diagenetic processes in the new unit are itiidites, Arecipites, Grimsdalea), Bombacoideae (Bombacacidites) siderite cementation and low compaction. Contacts between fl and freshwater algae (Botryococcus, Pediastrum). Likewise, other grains predominantly point-to-point or oating, associated with vegetation groups point to the existence of more open conditions a loose packing, suggest the deposit experienced telodiagenesis that is the case of grasses (M. annulatus) and other herbs marked by shallow burial, what inhibited more advanced levels (E. spinosus, C. longispinosus, F. spinosus, S. evansii). Such conditions of mechanical and/or chemical compaction. This packing suggests can be associated with meadow areas like swamps of Mauritia that siderite cementation happened before the effects of physical (Mauritiidites spp.), but could also indicate primary vegetation compaction. The results of telodiagenesis are supported by growing on fluvial bars, a common occurrence in Amazonian river stratigraphic data of the studied section that shows capping by plains, and in areas of forest close to the channels that are peri- late Pleistocene-Holocene Negro River deposits, with around odically flooded. These results agree with the presence of angio- 30 m in thickness. Due to its friable characteristic, there are no ~ sperm macrofossils in the arenite facies, which validate their fluvial diagenetic data on the underlying unit (Alter do Chao Formation) nature, where leaves and wood fragments were preserved in sand in the area. bars. Siderite cement and abundant fossils (mainly leaves) in the Cretaceous, Neogene and Late Palaeozoic reworked paly- arenite beds were important for its differentiation from the un- ~ nomorphs indicate a source area with Andean contribution to the derlying Eocene-middle Miocene Alter do Chao Formation. The studied deposit. Because Cretaceous and Late Paleozoic strata are latter contains mainly ferruginous cements (goethite) and local buried by Cenozoic strata west of Manaus, only the Andean chain, occurrences of logs, wood remains, and fruits, but all replaced by Precambrian and Solimoes~ Formation rocks could be exposed and the above mentioned mineral iron phase (Dino et al., 2012). eroded in the region. The presence of Andean (A. verus and Podo- Siderite is characteristic in reducing zones with abundant organic carpidites sp.) and reworked taxa also confirms that by the late matter (Rodrigues et al., 2015). Eodiagenetic siderite (FeCO3)has Pliocene-early Pleistocene times the Purus arch was no longer a been described in many sedimentary environments like marshes, geographic barrier. lakes and tidal plains and is an indicator of reducing sedimentary conditions produced by organic matter degradation by different groups of bacteria during early diagenesis (Berner, 1971, 1981; 4.4. Sedimentation environment, diagenesis and correlations Maynard, 1982; Curtis, 1987). In fluvial deposits, siderite is found in floodplains, crevasse splays, meander bars and marshes The studied siderite bearing unit is composed mainly of are- (Morad, 1998). nite and subordinate pelite and conglomerate. This E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 223

The variety of rock fragment grains (igneous, sedimentary 2e3kmchannels(Latrubesse and Franzinelli, 2005). Therefore, and metamorphic) and the assemblage (unstable to ultrastable) our ~1.8 km channel deposit is comparable to channel widths in of transparent heavy minerals (zircon, tourmaline, rutile, most reaches of the Negro River. The minimal age offered herein kyanite, sillimanite, apatite, topaz, garnet and hornblende) as and the possible large scale nature of the reconstructed channel well as the variable roundness degree of zircons in the arenites is in line with paleogeographical models derived from avian allow us to infer a high variety of source areas for the studied phylogenies that support river barriers since the late Pliocene deposit. The mineralogical diversity of the heavy mineral (Ribas et al., 2012; d'Horta et al., 2013, Sousa-Neves et al., 2013; assemblage is compatible with that found in the Alter do Chao~ Fernandes et al., 2014; Ferreira et al., 2017). Formation, thus being potentially the primary source of the deposit, with a secondary contribution from units from other source areas (Guyana Shield, Andean Chain and Solimoes~ For- 5. Conclusions mation), what is also supplemented by the provenance of palynomorphs. In the present contribution we reported a thin deposit of a yet undescribed chronostratigraphic unit in the lower course of the 4.5. Geochronological evidence for the lower Negro River evolution Negro River in central Amazonia. Sedimentological, stratigraphical, mineralogical and palynological data obtained from Alluvial deposits of the Negro River are restricted to a narrow drill holes across the current Negro River channel allowed the fi band, largely driven by structural controls of this river identi cation of a thin siderite bearing sedimentary deposit sit- fl (Latrubesse and Franzinelli, 2002, 2005; Silva et al., 2007). uated 30 m below the river oor and continuous for 1800 m. This Latrubesse and Franzinelli (2005) subdivided this river in six unit unconformably overlays the middle Miocene beds (Upper ~ reaches (I to VI) and performed radiocarbon dating of alluvial Alter do Chao Formation) and is capped by Late Pleistocene- deposits, recording ages between 1 and 40 ka. The oldest fluvial Holocene Negro River channel sediments. Palynological data terraces located in reach I (upstream) were associated to a Middle suggest a chronological position around the late Pliocene to early Pleniglacial age (65e25 ka) and similar age ranges are found in Pleistocene (Piacenzian to Gelasian, ~3.6 to 1.9 Ma). The strati- the lower course (Soares et al., 2010; Sant'Anna et al., 2017). graphic position of this deposit as well as its varied lithology However, active fluvial sedimentation was already in place before (arenite, pelite and conglomerate) permit a preliminarily inter- fl the Late Pleistocene as evidenced by the age proposed herein for pretation as bars associated with a sizable post-Miocene uvial the Negro River's lower course sediments. Furthermore, the system deposition installed in Central Amazonia. The pollen fl Purus arch as a hydrographic barrier by the late Pliocene-early assemblage plus abundant leaf and wood fossils in uvial bars, Pleistocene time cannot be supported. This is in agreement with little evidence for fragmentation or wearing corroborates with the overall drainage evolution scenarios that indicate a late the proposed paleoenvironmental interpretation and suggests a Miocene transcontinental establishment for the Amazon basin quick and short transport of the plant fragments. Andean pollen (Figueiredo et al., 2009; Hoorn et al., 2010, 2017; Caputo and grains at this late Pliocene-early Pleistocene unit show that Soares, 2016). during this time the Purus arch was not a geographical barrier The fact that the deposits here studied contain a significant and that the system drained material from the Andes and Sol- ~ amount of Andean derived palynomorphs (including reworked imoes Formation until central Amazonia and into the Atlantic ones) and a mixed origin of rock fragments and heavy minerals, Ocean. indicates a connection of the reconstructed channel with Andean headwaters in the past. If rivers in the upper Negro River basin were connected to rivers with Andean origins this is yet to be Acknowledgments shown and not the scope of this work. A simpler hypotheses would be that the position of the Negro's lower course and The authors thank Consorcio Rio Negro (Camargo Correa^ and consequentially the Negro-Solimoes~ system confluence was Construbase Engenharia) and the partnership [number 255/2009- further west compared to currently (e.g. Almeida-Filho and SG/SRMM] between the Secretaria de Desenvolvimento Sus- Miranda, 2007) and only attained after the late Pliocene-early tentavel da Regiao~ Metropolitana de Manaus (SRMM) and the Pleistocene. Neotectonic control of many regional rivers, Geosciences Department (DEGEO) of the Federal University of including megacaptures by trunk rivers like the Negro and Amazonas (UFAM), for authorizing access to the cores from bore- Amazon is an important aspect of fluvial development in the holes made for the building of the Negro River Bridge. We also Upper Pleistocene (Almeida-Filho and Miranda, 2007; Rossetti thank CPRM (Geological Survey of Brazil-Manaus) for the x-ray et al., 2014; Cremon et al., 2016). diffraction analysis and making the thin sections. We also thank The extension of the studied unit (traceable for ca. 1800 m) funding from Coordenaçao~ de Aperfeiçoamento de Pessoal em supports that large scale rivers were already installed in the Nível Superior e CAPES [Grant number BEX 0376/12-4 to C.D.]. immense and biogeographically important confluence (Amazon- Finally, we thank Valentí Rull, Carina Hoorn and an anonymous Negro) by at least the late Pliocene. Channel widths along the referee for peer review. Negro River (Latrubesse and Franzinelli, 2005) vary considerably -widthsof~1.5to6e7 km have been recorded in channels of different reaches of this river. In some places like the Branco River area, confinement leads to narrower channels (~1.5e2 km), whereas other places are broader like in the Anavilhanas archi- Appendix pelago. The Anavilhanas block is 18e20 km wide, but channels occupy ca. 33% of this area, i.e. ~6e7 km, mostly divided into 224 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229

Fig. A1. 1) Kuylisporites waterbolkii,2)Laevigatosporites tibuensis,3)Magnastriatites grandiosus,4e5) Matonisporites muelleri,6e7) Polypodiaceoisporites amazonensis,8)Poly- podiisporites aff P. specious,9)Verrucatotriletes etayoi,10e11) Alnipollenites verus,12)Arecipites regio,13)Bombacacidites ciriloensis. E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 225

Fig. A2. 1e2) Cichoreacidites longispinosus,3)Clavainaperturites microclavatus,4e5) Clavamonocopites lorentei,6e7) Crototricolpites ﬁnitus,8)Echiperiporites akanthos,9)Echiper- iporites lophatus,10e12) Echitricolporites spinosus,13e14) Fenestrites spinosus,15)Grimsdalea magnaclavata,16e17) Ilexpollenites tropicalis,18e19) Mauritiidites franciscoi var. franciscoi, 20) Mauritiidites franciscoi var. minutus. 226 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229

Fig. A3. 1e2) Mauritiidites franciscoi var. pachyexinatus,3)Monoporopollenites annulatus,4)Paleosantalaceaepites cingulatus,5e6) Parsonidites? brenacii,7)Perisyncolporites pokornyi, 8) Proteacidites triangulatus,9e10) Psilatricolporites labiatus,11)Psilatricolporites operculatus,12)Psilatricolporites silvaticus,13e14) Retitrescolporites? irregularis,15e16) Spi- rosyncolpites spiralis,17e20) Stephanocolpites evansii. E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 227

Table A1 Pollen raw counts of samples from the Negro River palaeochannel deposit, Manaus, Brazil (RW ¼ reworked).

Type Taxa/sample ap-68 ap-47 ap-48-3 ap-48-2

algae Botryococcus spp 1 algae Pediastrum spp 3 RW pollen Afropollis jardinus 1 pollen Alnipollenites verus 20 5 pollen Angio indet 2 pollen Arecipites regio 1 pollen Bombacacidites ciriloensis 13 pollen cf. Echitricolporites mcneillyi 1 pollen Cichoreacidites longispinosus 3 RW pollen Classopollis classoides 1 pollen Clavainaperturites microclavatus 871 pollen Clavamonocolpites lorentei 22 RW pollen Cretacaeiporites polygonalis 1 pollen Crototricolpites ﬁnitus 1 pollen Echiperiporites aff. akanthos 1 pollen Echiperiporites akanthos 111 pollen Echiperiporites lophatus 2 pollen Echitricolporites spinosus 13 17 1 RW pollen Equisetosporites sp 1 pollen Ericipites cf annulatus 22 pollen Fenestrites “igapoensis” 2 pollen Fenestrites spinosus 2 pollen Foveotricolporites sp1 1 pollen Grimsdalea magnaclavata 1 pollen Ilexpollenites tropicalis 11 13 pollen Malvacipolloides aff. maristellae 1 pollen Margocolporites aff. fastigiatus 1 pollen Margocolporites spp 1 pollen Mauritiidites franciscoi var. franciscoi 13 17 1 pollen Mauritiidites franciscoi var. minutus 1 pollen Mauritiidites franciscoi var. pachyexinatus 1 pollen Monoporopollenites annulatus 22 55 6 pollen Paleosantalaceaepites cingulatus 1 1 pollen Parsonidites? brenacii 1 pollen Perisyncolporites pokornyi 13 pollen Podocarpidites spp 1 pollen Proteacidites triangulatus 11 RW pollen Psilabrevitricolporites devriesii 1 pollen Psilabrevitricolporites sp1 1 pollen Psilastephanocolpories “myrsinoides” 1 pollen Psilastephanocolporites aff marinamensis 1 pollen Psilatricolporites labiatus 3 pollen Psilatricolporites “lolongatis” 33 pollen Psilatricolporites “marcgraveae” 1 pollen Psilatricolporites operculatus 2 pollen Psilatricolporites silvaticus 54 pollen Psilatricolporites sp1 1 pollen Psilatricolporites spp 8 11 pollen Psilatriporites “farameoides” 1 pollen Retimonocolpites sp1 1 pollen Retistephanocolpites sp1 1 pollen Retistephanocolporites sp1 1 pollen Retistephanoporites sp1 1 pollen Retitrescolpites? irregularis 43 pollen Retitricolpites sp1 1 pollen Retitricolporites “manausensis” 3 pollen Retitricolporites sp1 1 pollen Retitricolporites spp 9 6 6 pollen Rhoipites “negroensis” 2 pollen Siltaria cf. dilcheri 1 pollen Spirosyncolpites spiralis 12 pollen Stephanocolpites evansii 2 pollen Striatopollis catatumbus?1 pollen Striatricolporites spp 1 pollen Syncolporites aff. anibalii 1 spore Camarozonosporites cf. crassus 1 spore cf. Neoraistrickia 1 spore Cingulatisporis sp1 1 RW spore Crassoretitriletes vanraadshoovenii 1 spore Echinatisporis sp1 1 spore Echinatisporis spp 1 spore Echinosporis sp1 1 RW spore Foveotriletes ornatus 11 (continued on next page) 228 E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229

Table A1 (continued )

Type Taxa/sample ap-68 ap-47 ap-48-3 ap-48-2

spore Kuylisporites waterbolkii 1 spore Laevigatosporites tibuensis 12 16 3 spore Magnastriatites grandiosus 2 spore Matonisporites muelleri 1 spore Polypodiaceoisporites amazonensis 1 spore Polypodiaceoisporites sp1 1 spore Polypodiisporites aff. specious 18 spore Polypodiisporites cf. scabraproximatus 13 spore Polypodiisporites sp1 1 spore Polypodiisporites sp2 1 spore Polypodiisporites spp 11 13 spore Psilatrieltes lobatus 1 spore Psilatriletes >50 mm 6 spore Psilatriletes 25e50 mm 25 27 2 1 spore Psilatriletes sp1 1 spore Spore indet 1 spore Verrucatotriletes etayoi 3 spore Verrucatotriletes sp1 2 spore Verrutriletes spp 2 spore Verrucatotriletes “tortum” 1 RW spore Waltzispora?1

Sample ap-47 ¼ borehole F-9; sample ap-48 ¼ borehole F-10; sample ap-68 ¼ borehole not plotted in Fig. 1.

References Fernandes, M.F., Wink, M., Sardelli, C.H., Aleixo, A., 2014. Multiple speciation across the Andes and throughout Amazonia: the case of the spot-backed antbird species complex (Hylophylax naevius/Hylophylax anevioides). J. Biogeogr. 41 (6), Absy, M.L., 1979. A Palynological Study of Holocene Sediments in the Amazon Basin. 1094e1104. http://dx.doi.org/10.1111/jbi.12277. PhD Thesis. University of Amsterdam., Netherlands. Ferreira, M., Aleixo, A., Ribas, C.C., Santos, M.P.D., 2017. Biogeography of the Almeida-Filho, R., Miranda, F.P., 2007. Mega capture of the rio Negro and formation Neotropical genus Malacoptila (Aves: Bucconidae): the influence of the Andean of the Anavilhanas Archipelago, central Amazonia,^ Brazil: evidences in a SRTM orogeny, Amazonian drainage evolution and Palaeoclimate. J. Biogeogr. 44, digital elevation model. Remote Sens. Environ. 110 (3), 387e392. https://doi. 748e759. http://dx.doi.org/10.1111/jbi.12888. org/10.1016/j.rse.2007.03.005. Figueiredo, J., Hoorn, C., Van Der Ven, P., Soares, E., 2009. Late Miocene onset of the Ayres, J.M.C., Clutton-Brock, T.H., 1992. River boundaries and species range size in Amazon River and the Amazon deep-sea fan: evidence from the Foz do Ama- Amazonian primates. Am. Nat. 140, 531e537. http://dx.doi.org/10.1086/285427. zonas Basin. Geology 37, 619e622. http://dx.doi.org/10.1130/G25567A.1. Berner, R.A., 1971. Principles of Sedimentology. McGraw-Hill, New York. Fiore, M., Soares, E.A.A., Mittani, J.C.R., Yee, M., Tatumi, S.H., 2014. OSL dating of Berner, R.A., 1981. A new geochemical classification of sedimentary environments. sediments from Negro and Solimoes~ rivers e Amazon, Brazil. Radiat. Phys. J. Sediment. Petrol 51, 359e365. http://dx.doi.org/10.1306/212F7C7F-2B24- Chem. 95, 113e115. https://doi.org/10.1016/j.radphyschem.2012.12.041. 11D7-8648000102C1865D. Folk, R.L., 1974. Petrology of Sedimentary Rocks. Hemphill, Austin, Texas. Caputo, M.V., 2011. Discussao~ sobre a Formaçao~ Alter do Chao~ e o Alto de Monte Franzinelli, E., Igreja, H., 2002. Modern sedimentation in the lower Negro River, Alegre. In: Nascimento, R.S.C., Horbe, A.M.C., Almeida, C.D. (Eds.), Contribuiçao~ a Amazonas state, Brazil. Geomorphology 44, 259e271. http://dx.doi.org/10.1016/ geologia da Amazonia.^ Sociedade Brasileira de Geologia, Belem, pp. 7e23. S0169-555X(01)00178-7. Caputo, M.V., Soares, E.A.A., 2016. Eustatic and tectonic change effects in the Germeraad, J.H., Hopping, C.A., Muller, J., 1968. Palynology of Tertiary sediments reversion of the transcontinental Amazon River drainage system. Braz. J. Geol. from tropical areas. Rev. Palaeobot. Palyno 6, 189e348. http://dx.doi.org/ 46 (2), 301e328. http://dx.doi.org/10.1590/2317-4889201620160066. 10.1016/0034-6667(68)90051-1. Collinson, J.D., 1996. Alluvial sediments. In: Reading, H.G. (Ed.), Sedimentary Envi- Gonçalves Jr., E.S., Soares, E.A.A., Tatumi, S.H., Mittani, J.C.R., 2016. Solimoes-Amazon~ ronments and Facies, 3 ed. Blackwell, Oxford, pp. 37e38. fluvial system between the tributaries Negro and Madeira, Central Amazon. CPRM, 2010. Mapa Geologico do Brasil. Serv. Geol. Brasil, Brasília. On-line URL: Braz. J. Geol. 46 (2), 167e180. http://dx.doi.org/10.1590/2317- http://geobank.sa.cprm.gov.br. 4889201620160009. Cremon, E.H., Rossetti, D.F., Sawakuchi, A.O., Cohen, M.C.L., 2016. The role of tec- Gorini, C., Haq, B.U., dos Reis, A.T., Silva, C.G., Cruz, A., Soares, E., Grangeon, D., 2013. tonics and climate in the late Quaternary evolution of a northern Amazonian Late Neogene sequence stratigraphic evolution of the Foz do Amazonas Basin, River. Geomorphology 271, 22e39. http://dx.doi.org/10.1016/j.geomorph.2016. Brazil. Terra Nova 26 (3), 179e185. http://dx.doi.org/10.1111/ter.12083. 07.030. Hilgen, F.J., Lourens, L.J., Van Dam, J.A., Beu, A.G., Boyes, A.F., Cooper, R.A., Cronquist, A., 1981. An integrated system of classification of flowering plants. In: Krijgsman, W., Ogg, J.G., Piller, W.E., Wilson, D.S., 2012. The Neogene period. In: Sambamurty, A.V.S.S. (Ed.), Taxonomy of Angiosperms. 2005. Columbia Uni- Gradstein, F.M., Schmitz, J.G.O.D., Ogg, G.M. (Eds.), The Geologic Time Scale. versity Press, New York, pp. 50e56. Elsevier, Boston, pp. 923e978. Curtis, C.D., 1987. Mineralogical consequences of organic matter degradation in Hooghiemstra, H., 1989. Quaternary and Upper Pliocene glaciations and Forest sediments: inorganic/organic diagenesis. In: Leggett, J.K., Zuffa, G.G. (Eds.), development in the tropical Andes: evidence from a long high resolution pollen Marine Clastic SedimentologydConcepts and Case Studies. Graham and Trot- Record from the sedimentary basin of Bogota, Colombia. Paleogeogr. Palae- man Inc., Norwell, pp. 108e123. oclimatol. Palaeoecol. 72, 11e26. http://dx.doi.org/10.1016/0031-0182(89) Daemon, R.F., 1975. Contribuiçao~ a dataçao~ da Formaçao~ Alter do Chao,~ Bacia do 90129-6. Amazonas. Rev. Bras. Geoc 5 (2), 58e84. Horbe, A.M.C., Motta, M.B., Almeida, C.M., Dantas, E.L., Vieira, L.V., 2013. Provenance d'Horta, F.M., Cuervo, A.M., Ribas, C.C., Brumfield, R.T., Miyaki, C.Y., 2013. Phylogeny of Pliocene and recent sedimentary deposits in western Amazonia,^ Brazil: and comparative phylogeography of Sclerurus (Aves: Furnariidae) reveal con- consequences for the paleodrainage of the Solimoes-Amazonas~ River. Sediment. stant and cryptic diversification in an old radiation of rain forest understorey Geol. 296, 9e20. http://dx.doi.org/10.1016/j.sedgeo.2013.07.007. specialists. J. Biogeogr. 40, 37e49. http://dx.doi.org/10.1111/j.1365- Hoorn, C., Wesselingh, F.P., ter Steege, H., Bermúdez, M.A., Mora, A., Sevink, J., 2699.2012.02760.x. Sanmartín, I., Sanchez-Meseguer, A., Anderson, C.L., Figueiredo, J.P., Jaramillo, C., Dino, R., da Silva, O.B., Abrahao,~ D., 1999. Caracterizaçao~ palinologica e estratigrafica Riff, D.D., Negri, F.R., Hooghiemstra, H., Lundberg, J., Stadler, T., Sarkinen,€ T., de estratos cretaceos da Formaçao~ Alter do Chao,~ Bacia do Amazonas. In: Antonelli, A., 2010. Amazonia through time: Andean uplift, climate change, Boletim do 5o do Simposio sobre o Cretaceo do Brasil. UNESP, Serra Negra, landscape evolution and biodiversity. Science 330, 927e931. http://dx.doi.org/ pp. 557e565. 10.1126/science.1194585. Dino, R., Soares, E.A.A., Riccomini, C., Antonioli, L., Nogueira, A.C.R., 2012. Palynos- Hoorn, C., Bogota, G.R., Romero, M., Lammertsma, E.I., Flantua, S., Dantas, E.L., tratigraphy and sedimentary facies of middle Miocene fluvial deposits of the Dino, R., do Carmo, D.A., Chemale, F., 2017. The Amazon at sea: onset and stages Amazonas Basin, Brazil. J. S. Am. Earth Sci. 34 (8), 61e80. http://dx.doi.org/10. of the Amazon River from a marine record, with special reference to Neogene 1016/j.jsames.2011.11.008. plant turnover in the drainage basin. Glob. Planet. Change 153, 15e65. http://dx. Feitosa, Y.O., Absy, M.L., Latrubesse, E.M., Stevaux, J.C., 2015. Late Quaternary doi.org/10.1016/j.gloplacha.2017.02.00. vegetation dynamics from central parts of the Madeira River in Brazil. Acta Bot. Jaramillo, C., Rueda, M., Torres, V., 2011. A palynological zonation for the Cenozoico Bras. 29 (1), 120e128. http://dx.doi.org/10.1590/0102-33062014abb3711. of the Llanos and Llanos Foothills of Colombia. Palynology 35 (1), 46e84. http:// E.A.A. Soares et al. / Journal of South American Earth Sciences 79 (2017) 215e229 229

dx.doi.org/10.1080/01916122.2010.515069. and biogeography in Neotropical Brotogeris parakeets. J. Biogeogr. 36, Jaramillo, C.A., Rueda, M., 2016. A Morphological Electronic Database of Cretaceous- 1712e1729. http://dx.doi.org/10.1111/j.1365-2699.2009.02131.x. tertiary and Extant Pollen and Spores from Northern South America. v. 2017. Rodrigues, A.G., Ros, L.F., Neumann, R., Borghi, L., 2015. Paleoenvironmental im- Available at: http://biogeodb.stri.si.edu/jaramillo/palynomorph. plications of early diagenetic siderites of the Paraíba do Sul Deltaic Complex, Latrubesse, E.M., 2008. Patterns of anabranching channels: the ultimate end- eastern Brazil. Sediment. Geol. 323, 15e30. http://dx.doi.org/10.1016/j.sedgeo. member adjustment of mega rivers. Geomorphology 101, 130e145. http:// 2015.04.005. dx.doi.org/10.1016/j.geomorph.2008.05.035. Rossetti, D.F., Cohen, M.C.L., Bertani, T.C., Hayawaka, E.H., Paz, J.D.S., Castro, D.F., Latrubesse, E.M., Franzinelli, E., 2002. The Holocene alluvial plain of the middle Friaes, Y., 2014. Late Quaternary fluvial terrace evolution in the main southern Amazon River, Brazil. Geomorphology 44, 241e257. http://dx.doi.org/10.1016/ Amazonian tributary. Catena 116, 19e37. http://dx.doi.org/10.1016/j.catena. S0169-555X(01)00177-5. 2013.11.021. Latrubesse, E.M., Franzinelli, E., 2005. The late Quaternary evolution of the Negro Rossetti, D.F., Cohen, M.C.L., Tatumi, S.H., Sawakuchi, A.O., Cremon, E.H., river, Amazon, Brazil: implications for island and floodplain formation in large Mittani, J.C.R., Bertani, T.C., Munita, C.J.A.S., Tudela, D.R.G., Yee, M., Moya, G., anabranching tropical systems. Geomorphology 70, 372e397. http://dx.doi.org/ 2015. Mid-Late Pleistocene OSL chronology in western Amazonia and impli- 10.1016/j.geomorph.2005.02.014. cations for the transcontinental Amazon pathway. Sediment. Geol. 330, 1e15. Latrubesse, E.M., Cozzuol, M., da Silva-Caminha, S.A.F., Rigsby, C.A., Absy, M.L., http://dx.doi.org/10.1016/j.sedgeo.2015.10.001. Jaramillo, C., 2010. The late Miocene paleogeography of the Amazon Basin and Sa, N.P., Absy, M.L., Soares, E.A.A., 2016. Late Holocene paleoenvironments of the the evolution of the Amazon River system. Earth Sci. Rev. 99, 99e124. http://dx. floodplain of the Solimoes~ River, Central Amazonia, based on the palynological doi.org/10.1016/j.earscirev.2010.02.005. record of lake Cabaliana. Acta Bot. Bras. 30 (3), 473e485. http://dx.doi.org/10. Leite, F.P.R., Paz, J., Carmo, D.A., Silva-Caminha, S.A., 2016. The effects of the 1590/0102-33062016abb0250. inception of Amazonian transcontinental drainage during the Neogene on the Sacek, V., 2014. Drainage reversal of the Amazon River due to the coupling of landscape and vegetation of the Solimoes~ Basin, Brazil. Palynology 1e11. http:// surface and lithospheric processes. Earth Planet. Sc. Lett. 401, 301e312. https:// dx.doi.org/10.1080/01916122.2016.1236043. doi.org/10.1016/j.epsl.2014.06.022. Lorente, M.A., 1986. Palynology and Palinofacies of the Upper Tertiary in Venezuela. Sant'Anna, L.G., Soares, E.A.A., Riccomini, C., Tatumi, S.H., Yee, M., 2017. Age of Ph.D. thesis. University of Amsterdam. depositional and weathering events in Central Amazonia. Quat. Sci. Rev. 170, Miall, A.D., 1992. Alluvial deposits. In: Walker, R.G., James, N.P. (Eds.), Facies Models: 82e97. http://dx.doi.org/10.1016/j.quascirev.2017.06.015. Response to Sea Level Change. St. John's, Geological Association of Canada, Silva, J.M.C., Rylands, A.B., Fonseca, G.A.B., 2005. The fate of Amazonian areas of pp. 119e142. endemism. Conserv. Biol. 19, 689e694. http://dx.doi.org/10.1111/j.1523- Maia, R.G., Godoy, H.K., Yamaguti, H.S., Moura, P.A., Costa, F.S., 1977. Projeto Carvao~ 1739.2005.00705.x. no Alto Solimoes.~ Final report. CPRM, Rio de Janeiro. Silva, C.L., Morales, N., Crosta, A.P., Costa, S.S., Jimenez-Rueda, J.R., 2007. Analysis of Maynard, J.B., 1982. Extension of Berner's “new geochemical classification of sedi- tectonic- controlled fluvial morphology and sedimentary processes of the mentary environments” to ancient sediments. J. Sediment. Petrol 52, Western Amazon Basin: an approach using satellite images and digital eleva- 1325e1331. http://dx.doi.org/10.1306/212F812F-2B24-11D7- tion model. An. Acad. Bras. Cienc 79 (4), 693e711. http://dx.doi.org/10.1590/ 8648000102C1865D. S0001-37652007000400010. Morad, S., 1998. Carbonate cementation in sandstones: distribution patterns and Silva-Caminha, S.A.F., Jaramillo, C., Absy, M.L., 2010. Neogene palynology of the geochemical evolution. In: Morad, S. (Ed.), Carbonate Cementation in Sand- Solimoes~ Basin, Brazilian Amazonia. Palaeontogr. Abt. B 284 (1e3), 13e79. stones, vol. 26. International Association of Sedimentologists Special Publica- Shephard, G.E., Müller, R.D., Liu, L., Gurnis, M., 2010. Miocene drainage reversal of tion, pp. 1e26. the Amazon River driven by plateemantle interaction. Nat. Geosci. 3, 870e875. Müller, J., Giacomo, E., Van Erve, A.W., 1987. A Palynological Zonation for the http://dx.doi.org/10.1038/NGEO1017. Cretaceous, Tertiary and Quaternary of Northern South America, 19. American Soares, E.A.A., Tatumi, S.H., Riccomini, C., 2010. OSL age determinations of Pleisto- Association of Stratigraphic Palynologists, pp. 7e76. Contribution Series. cene fluvial deposits in central Amazonia. An. Acad. Bras. Cienc 82 (3), 691e699. Nogueira, A.C.R., Silveira, R., Guimaraes,~ J.T.F., 2013. Neogene-Quaternary sedi- http://dx.doi.org/10.1590/S0001-37652010000300017. mentary and paleovegetation history of the eastern Solimoes~ Basin, central Soares, E.A.A., Dino, R., Soares, D.P., Antonioli, L., Silva, M.A.L., 2015. New Sedi- Amazon region. J. S. Am. Earth Sci. 46, 89e99. http://dx.doi.org/10.1016/j. mentological and Palynological data from outcropping Miocene strata in the jsames.2013.05.004. central portion of the Amazon Basin. Braz. J. Geol. 45 (3), 337e357. http://dx. Pocknall, D.T., Wood, L.J., Green, A.F., Harry, B.E., Hedlund, R.W., 2001. Integrated doi.org/10.1590/2317-488920150030283. Paleontological studies of Pliocene to Pleistocene deposits of the Oricono Delta, Soares, E.A.A., Whanfried, I., Dino, R., 2016. Estrattigrafia de subsuperfície da eastern Venezuela and Trinidad. In: Goodman, D.K., Clarke, R.T. (Eds.), Pro- seqüencia^ sedimentar Cretacea-Ne ogena das regioes~ de Manaus e Itacoatiara, ceedings of the IX International Palynological Congress, Houston, Texas, USA, Amazonia^ Central. Geol. USP Ser. Cient. 16 (1), 23e41. http://dx.doi.org/10. 1996. American Association of Stratigraphic Palynologists Foundations, 11606/issn.2316-9095.v16i1p23-41. pp. 319e326. Sousa-Neves, T., Aleixo, A., Sequeira, F., 2013. Cryptic patterns of diversification of a Potonie, R., 1934. Zur Morphologie der fossilen Pollen und Sporen. Arb. Inst. Pal- widespread Amazonian species complex (Aves: Dendrocolaptidae) inferred iiobotan. Petrog. Brennstein. 4, 5e24. from multilocus phylogenetic analysis: implications for historical biogeography Reis, N.J., Almeida, M.E., Riker, S.L., Ferreira, A.L., 2006. Geologia e recursos minerais and taxonomy. Mol. Phylogenet. Evol. 68, 410e424. http://dx.doi.org/10.1016/j. do Estado do Amazonas (texto explicativo dos mapas geologicos e de recursos ympev.2013.04.018. minerais do Estado do Amazonas). Serv. Geol. Brasil. CPRM, Manaus. Van Der Hammen, T., 1956. A Palynological Systematic Nomenclature e Boletín Ribas, C.C., Aleixo, A., Nogueira, A.C.R., Miyaki, C.Y., Cracraft, J., 2012. Geologico (Bogota), vol. 4, pp. 63e101. A Paleobiogeographic model for biotic diversification within Amazonia over the Wood, G.D., Grabriel, A.M., Lawson, J.C., 1996. Palynological techniques e processing past three million years. P. R. Soc. B 279, 681e689. http://dx.doi.org/10.1098/ and microscopy. In: Jansonius, J., McGregor, D.C. (Eds.), Palynology: Principles rspb.2011.1120. and Applications 1. American Association of Stratigraphic Palynologists Foun- Ribas, C.C., Miyaki, C.Y., Cracraft, J., 2009. Phylogenetic relationships, diversification dation, Dallas, Texas, pp. 29e50.