scholarly journals POLLEN RECORDS FROM THE OLIGOCENE OF WESTERN INDONESIA AS THE EVIDENCES OF CLIMATE CHANGES

2018 ◽  
Vol 40 (3) ◽  
pp. 107-115
Author(s):  
Eko Budi Lelono
Keyword(s):  
Rain Forest ◽  
Climate Changes ◽  
Lacustrine Sediments ◽  
Pollen Assemblage ◽  
Preparation Methods ◽  
Shallow Marine ◽  
Seasonal Climate ◽  
Early Oligocene ◽  
Climate Indicators ◽  
Wet Climate

In Southeast Asia, Oligocene climate is well known to be represented by dry/ seasonal climate. However, it was reported possible appearance of wet climate period during the expantion of dry condition. This work is aimed to confi rm the Oligocene climate which occurred in western Indonesia. Climate change is useful to understand the Oligocene stratigraphy of Western Indonesia. This study uses cutting samples from off shore exploration wells situated in West and East Java and West Natuna as well as on-shore Central Sumatera and West Java. Samples are processed using standard preparation methods to produce suitable pollen assemblage for quantitative analysis.This study proves that the Oligocene sediments yield rich pollen assemblages including those of environment and climate indicators. Abundant fresh water algae of Pediastrum and Bosedinia in Early Oligocene indicates the appearance of lacustrine sediments. This sediment was formed under dry/ seasonal climate as marked by rich grass pollen Monoporites annulatus in the absence or rare occurance of rain forest elements. Mean while, Late Oligocene is characterised by common brackish elements to indicate shifting paleoenvironment into transition to shallow marine. The climate was changing into wetter condition as evidenced by high appearance of Dacrydium and Casuarina as well as other rain forest palynomorphs. The wettest climate probably occured in Java region which refl ected a wet climate fringe to the eastern margin of Sundaland prior to the collision of the Australian and Asian Plates at the Oligo-Miocene boundary. However, in general, dry/ seasonal climate is the rule for most of the Oligocene in Western Indonesia.

The vegetation of the Solomon Islands

1969 ◽  
Vol 255 (800) ◽  
pp. 259-270 ◽  
Keyword(s):  
Rain Forest ◽  
Tropical Rain Forest ◽  
Solomon Islands ◽  
Seasonal Climate ◽  
Small Areas ◽  
Wet Climate

The Solomon Islands are entirely clothed in tropical rain forest except for small areas of probably anthropogenous grasslands and heaths which occur in regions with a seasonal climate. The main features of the vegetation are described and related to the exceptionally wet climate of the archipelago. The extensive areas which carry thickets of small trees and climber tangles instead of high forest are thought due to the combined influence of man, earthquake, landslip and cyclone. Many species are shown to have wide ecological amplitudes.

scholarly journals Optical Stimulation Luminescence Dating of Deltas Revealed the Early to Mid-Holocene Lake-level Fluctuations of Daihai, Inner Mongolia, Northern China

2021 ◽  
Vol 9 ◽  
Author(s):  
Shixin Huang ◽  
Xi Chun
Keyword(s):  
Lake Level ◽  
Climate Changes ◽  
Asian Summer Monsoon ◽  
Regional Climate ◽  
Lacustrine Sediments ◽  
Northern China ◽  
Luminescence Dating ◽  
Lake Area ◽  
Monsoon Precipitation ◽  
Lake Level Fluctuations

Lake-level reconstruction of inland enclosed lakes especially for monsoon-sensitive areas is of great significance to reveal regional climate changes. Daihai, a typical enclosed lake at the marginal of the East Asian summer monsoon (EASM) area in north China, is sensitive to climate changes due to its unique regional characteristics. There were a series of lakeshore terraces, highstand lacustrine sediments, and braided river deltas, providing sufficient geomorphologic and stratigraphic evidence for the reconstruction of lake-level fluctuations of Daihai. Reconstructed lake-level variations during the early and mid-Holocene were constructed based on 22 quartz optical stimulated luminescence (OSL) ages from six well-preserved profiles around Daihai Basin. Our results indicated Daihai showed a relatively low level at 10.2 ka, and a gradually increasing lake level following the enhanced monsoon precipitation during the mid-Holocene. Specifically, the high lake level began to develop at 8.1 ka and reached the maximum at 5.2 ka, with ∼40 m higher than present. At this time, the lake area expanded to ∼400 km2, approximately six times as large as that of present, corresponding to the maximum monsoon precipitation and intensity of EASM during the mid-Holocene. However, our stratigraphic records showed a part of the depositional records in the north and east of the Daihai was missed after 5.2 ka, probably indicating a sudden drop of the Daihai lake level. These rapid level fluctuations were likely to be interpreted by some local scenarios and need to be further investigated in the future. Overall, the lake-level fluctuation of Daihai during the early and mid-Holocene was slightly different from that observed in the previously published regional records. Possibly, the interaction of the EASM and regional feedback from topography, and hydrology factors might have contributed to the spatial complexity and distinction.

The youngest record of fossil land mammals from Antarctica; its significance on the evolution of the terrestrial environment of the Antarctic Peninsula during the late Eocene

1997 ◽  
Vol 71 (2) ◽  
pp. 348-350 ◽  
Author(s):  
S. F. Vizcaino ◽  
M. Bond ◽  
M. A. Reguero ◽  
R. Pascual
Keyword(s):  
Antarctic Peninsula ◽  
Present Note ◽  
Late Eocene ◽  
South American ◽  
Terrestrial Environment ◽  
Shallow Marine ◽  
Early Oligocene ◽  
La Meseta Formation ◽  
The Antarctic ◽  
Seymour Island

The record of fossil land mammals from Antarctica has been restricted previously to the middle levels of the Eocene-?early Oligocene La Meseta Formation in Seymour Island, Antarctic Peninsula. This mostly shallow-marine sequence was divided informally into seven subunits (Tertiary Eocene La Meseta or TELM 1 to 7) by Sadler (1988). Land mammals, representing South American lineages of marsupials, edentates, and ungulates were recovered from TELM 3, 4, and 5 (Marenssi et al., 1994; Vizcaíno et al., 1994). The purpose of the present note is to report the discovery of a well-preserved ungulate tooth from the uppermost level of the La Meseta Formation (TELM 7) and to discuss its paleoenvironmental implications.

scholarly journals The effects of seasonal climate changes in the caatinga on tannin levels in Myracrodruon urundeuva (Engl.) Fr. All. and Anadenanthera colubrina (Vell.) Brenan

2006 ◽  
Vol 16 (3) ◽  
pp. 338-344 ◽  
Author(s):  
Júlio M. Monteiro ◽  
Ulysses P. Albuquerque ◽  
Ernani M.F. Lins Neto ◽  
Elcida L. Araújo ◽  
Miracy M. Albuquerque ◽  
...  
Keyword(s):  
Climate Changes ◽  
Seasonal Climate

Bryophyte diversity along an altitudinal gradient in Darién National Park, Panama

1992 ◽  
Vol 5 (1) ◽  
pp. 61-71 ◽  
Author(s):  
S. Rob Gradstein ◽  
Noris Salazar Allen
Keyword(s):  
Species Richness ◽  
Coastal Plain ◽  
Rain Forest ◽  
National Park ◽  
Altitudinal Gradient ◽  
Plant Conservation ◽  
Montane Forest ◽  
Species Assemblages ◽  
Forest Types ◽  
Seasonal Climate

A bryophyte inventory along an altitudinal gradient on Cerro Pirre (1200 m), Darién National Park, Panama, demonstrates that the different rain forest types along the gradient (inundatedlowland, hillside-lowland, submontane, montane elfin forest) have very different species assemblages. The montane forest has the largest number of exclusive species and the largest bryophyte biomass. Species richness is greatest in the submontane forest. The bryophyte flora of Cerro Pirre is not exceedingly rich in species owing to the rather low elevation of the mountain and the seasonal climate in the adjacent coastal plain. Nevertheless, the distinct altitudinal diversification and the occurrence of a considerable number of rare hepatic taxa, demonstrate the importance of Darién National Park as an area of plant conservation. Forty hepatic species are reported as new to Panama.

scholarly journals The Paleogene Tectonostratigraphy Of Northern Part Masalima Trench Basin

2016 ◽  
Vol 1 (1) ◽  
pp. 7
Author(s):  
Luhut Pardamean Siringoringo ◽  
Dardji Noeradi
Keyword(s):  
Depositional Environment ◽  
Middle Eocene ◽  
Normal Faults ◽  
Tectonic Structure ◽  
Shallow Marine ◽  
Early Oligocene ◽  
Basin Formation ◽  
Java Sea ◽  
Seismic Sections ◽  
Well Data

Northern part of Masalima Trench Basin is located in the southern part of the Strait of Makassar, which includes Masalima Trough and Massalima High. The area of research is an extension of the South Makassar Basin which extends from South Makassar Basin to the Northeast part of Java Sea. Subsurface data are used such as 2D seismic sections (21 lines) and data drilling wells (2 wells) to understand the tectonic structure in the basin formation and understand the stratigraphic order of basin. Based on well data can be known that Northern part Masalima Trench Basin is aborted rift because marked by post rift phase. Northern part Masalima Trench Basin was formed by normal faults which have trend northeast-southwest with  pre rift, early syn rift, late syn rift, and post rift sediment geometry. Early syn rift sediment was Middle Eocene, late syn rift sediment was Middle Eocene till Early Oligocene and post rift sediment was Early Oligocene till Early Miocene. The Depositional environment of early syn rift phase such as beach, shallow marine, and land. The Depositional environment of late syn rift phase such as beach till deep marine, and the depositional environment of post rift is deep marine.

scholarly journals Radiocarbon Chronology of Late Glacial and Holocene Sedimentation and Water-Level Changes in the Area of the Gościąż Lake Basin

Radiocarbon ◽  
1994 ◽  
Vol 36 (2) ◽  
pp. 187-202 ◽  
Author(s):  
Anna Pazdur ◽  
M. F. Pazdur ◽  
Tomasz Goslar ◽  
Bogumił Wicik ◽  
Maurice Arnold
Keyword(s):  
Climate Changes ◽  
Global Climate ◽  
Lacustrine Sediments ◽  
Late Glacial ◽  
Lake Basin ◽  
Global Climate Changes ◽  
Laminated Sediment ◽  
Water Level Changes ◽  
Late Glacial And Holocene ◽  
Radiocarbon Chronology

We obtained 14C ages on samples of lake marl and other sediments from cores taken in Gościąż Lake and its environs. Comparison of 14C dates of bulk samples of laminated sediment with varve chronology and available AMS dates of terrestrial macrofossils indicates a reservoir correction of 2000 ± 120 yr for the basal series of lake sediments. 14C dates obtained on peat layers underlying the oldest lacustrine sediments in Gościąż and other lakes consistently locate the beginning of organogenic sedimentation in this area at ca. 13 ka bp. We distinguished three periods of lacustrine gyttja sedimentation in cores taken in Gościąż and adjacent lakes: 11.8–10.2 ka, 8–7 ka and 2.7–2.1 ka bp. From the 14C dates of lithological boundaries in these cores, we reconstruct a pattern of lake-level changes during the last 12 ka, remarkably similar to Swedish lakes and generally agreeing with available records from European and American lakes. The behavior of Gościąż Lake during the last 12 ka fairly well reflects global climate changes in the temperate zone during the Late Glacial and Holocene periods.

Obliquity-dominated glacio-eustatic sea level change in the early Oligocene: evidence from the shallow marine siliciclastic Rupelian stratotype (Boom Formation, Belgium)

Terra Nova ◽  
2007 ◽  
Vol 19 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Hemmo A. Abels ◽  
Stefaan Van Simaeys ◽  
Frits J. Hilgen ◽  
Ellen De Man ◽  
Noël Vandenberghe
Keyword(s):  
Sea Level ◽  
Sea Level Change ◽  
Shallow Marine ◽  
Level Change ◽  
Early Oligocene

Eocene–Oligocene stratigraphy and structural history of the Karaburun area, southwestern Black Sea coast, Turkey: transition from extension to compression

2015 ◽  
Vol 152 (6) ◽  
pp. 1104-1122 ◽  
Author(s):  
BORIS NATAL’IN ◽  
ADALET GIZEM SAY
Keyword(s):  
Black Sea ◽  
Tectonic Activity ◽  
Normal Faults ◽  
Shallow Marine ◽  
Early Oligocene ◽  
Marine Shale ◽  
Thrace Basin ◽  
Black Sea Coast ◽  
Nw Turkey ◽  
Sea Coast

AbstractThe stratigraphic succession exposed in the Karaburun area (southern Black Sea coast, NW Turkey) records multiple changes in depositional and tectonic settings during Cenozoic times. It starts with the Middle–Upper Eocene Soğucak Formation of reef limestone that across a normal fault, omitting the lower part of the Lower Oligocene Ceylan Formation (deep-marine shale unit), abuts the upper part of the Ceylan Formation that is made up of two facies: (1) shallow-marine sandstone and (2) shallow-marine limestone units containing horizons of submarine slumps. Both facies are unconformably overlain by the fluvial Upper Miocene Çukurçeşme Formation. The tectonic record includes: (1) latest Eocene – Early Oligocene NE–SW extension, (2) Early Oligocene NE–SW shortening and (3) Late Miocene NW–NE extension. The earliest normal faults cutting the Soğucak and the lower part of the Ceylan formations are associated with clastic dykes injected into the deep-marine shale. These structures suggest a disruption of the Eocene carbonate platform and are also known in the neighbouring Thrace Basin. The following NE–SW shortening created the NE-vergent Karaburun Thrust that is synchronous with the shallowing and inversion of the Ceylan Basin. Rotation of the stress field is recorded by changes in clastic dyke orientation and their deformation. Compression caused multiple westerly directed submarines slides from uplifts in easterly located regions. This event is not recorded in the Thrace Basin. Finally, the Miocene tectonic activity formed NW- and NE-striking normal faults. The outlined tectonic history includes Early Oligocene extensional and compressional episodes recorded in the southern margin of the Black Sea that had hitherto not been known.

Sign in / Sign up

Export Citation Format

Share Document