@conference {2017, title = {Microbial carbonates in Miocene reefs in the Mahakam Delta in East Kalimantan, Borneo, Indonesia}, booktitle = {SAGE2013 - Southeast Asian Gateway Evolution}, year = {2013}, month = {11/03/2013}, address = {Berlin, Germany}, abstract = {

Microbial carbonates are deposits that form by the activity of bentic microbial communities. Microbialites usually form domical, columnar or conical structures and can have laminated, clotted, dendritic or homogenous macrofabric. They have a broad distribution and can grow in a variety of different environments such as hot springs, freshwater lakes, hypersaline lakes, reefs and other marine environments. This research focuses on microbialites associated to coral reefs. Coral patch reefs in the Miocene Mahakam Delta in East Kalimantan (Borneo, Indonesia) grew in shallow marine turbid waters. These patch reefs developed from delta front to deeper (prodelta) settings in areas with temporary reduced siliciclastic input. Langhian reef deposits are well exposed in limestone quarries in the Samarinda area and locally include microbial carbonates. Two different types of microbial carbonates have been found around Samarinda in two localities 2 km apart. These sections were logged in detail and 208 samples were collected. Meso and macrostructure of microbialites were identified at the outcrops. Thin sections from carbonate samples were examined under optical microscope and microfacies were classified using the Dunham (1962) and Embry and Klovan (1971) terms. The carbonate content was analyzed using Total Inorganic Carbon analysis, with 12\% carbon as a standard for carbon calibration. In the northern section, microbialites occur as low-relief domes, up to 2 m wide and 0.5 m high, with internal lamination, developed around large coral fragments at the transition from reef deposits to fine-grained siliciclastics.
The second type of microbialites has been found in the southern locality as decimeter-scale nodules (\"megaoncoids\") formed around nuclei of large coral fragments. Small nodules were bound together into bigger nodules. Microbial micrite with laminated to digitated fabrics intergrew with coralline algae to form the thick covers of these \"megaoncoids\", which laterally change into coral boundstones. In both sections microbialites are not components of the reef framework. They grew around large coral fragments on the flanks of the patch reefs. The microbialites that form low relief domes developed on a nearly flat, stable seafloor seawards of the patch reef. The \"megaoncoids\" in the southern section formed as a result of downslope movement of coral fragments coated by microbialite/coralline algal crust. The steep slope at the flank of the patch reef favoured falling and overturning of encrusted corals and continued growth of microbial crusts on other sides of nodules.

}, author = {Vedrana Pretkovi{\'c} and Juan C. Braga and Vibor Novak and Anja R{\"o}sler and Willem Renema} } @conference {2066, title = {Thirty years of field-based {\textquoteright}Big Paleontology{\textquoteright} on Cenozoic shallow marine ecosystems}, booktitle = {10th North American Paleontological Convention}, year = {2014}, publisher = {The Paleontological Society Special Paper, 22}, organization = {The Paleontological Society Special Paper, 22}, address = { Gainesville, Florida}, author = {Kenneth G. Johnson and James Klaus and Jonathan A. Todd and Willem Renema and Ann F. Budd} } @conference {2066, title = {Oligocene and Miocene history of reef corals and coral reefs in eastern Borneo (East Kalimantan, Indonesia and Sabah, Malaysia)}, booktitle = {10th North American Paleontological Convention}, year = {2014}, publisher = {The Paleontological Society Special Paper, 22}, organization = {The Paleontological Society Special Paper, 22}, address = { Gainesville, Florida}, author = {Kenneth G. Johnson and Willem Renema and Nadiezhda Santodomingo} } @conference {Santodomingo2012, title = {Origins of coral diversity in Southeast Asia}, booktitle = {5 International Symposium on Deep-Sea Corals}, year = {2012}, address = {Amsterdam}, abstract = {

Southeast Asia hosts the maximum centre of coral diversity. Evidence from palaeontological and molecular studies suggests that the Miocene was an important period for diversification in the region. However, the fossil record is markedly undersampled. Of the \~{}200 species of azooxanthellate corals present in the region, only 49 species are known in the fossil record. As part of the Throughflow ITN project, we are collecting new data to document the Miocene diversity of zooxanthellate and azooxanthellate scleractinians from shallow and deep-water habitats preserved in outcrops of East Kalimantan (5-20 Million years old). This project has completed two five-week long field seasons and is currently processing samples. So far, we have identified the azooxanthellate taxa Caryophyllia, Stephanocyathus, Flabellum, Heterocyathus, and Madrepora. Preservation can be excellent allowing geochemical analysis to understand the paleoenviromental conditions in which these species were living. In combination with parallel studies on shallow water ecosystems, these new data provide insights to the origins of the high diversity in this region.

}, author = {Nadiezhda Santodomingo and Kenneth G. Johnson and Willem Renema} } @conference {2045, title = {Sub - annually resolved Miocene/Pliocene tropical palaeo - climate records from giant clams}, booktitle = {11th INTERNATIONAL CONFERENCE ON PALEOCEANOGRAPHY}, year = {2013}, publisher = {Sitges}, organization = {Sitges}, address = {Barcelona}, abstract = {

Changes in seasonality play an important role in regards to climate changes (e.g. Eldrett
et al.,
2009). To better characterize Miocene/Pliocene tropical climate and environmental change, it is
therefore crucial to reconstruct their variability on a seasonal scale. However, highly time resolve
d
palaeoenvironmental records which allow assessing
tropical intra
-
annual SST variability (like
ENSO or monsoon events) are rare, especially in \&$\#$39;deep
-
time\&$\#$39;.
Here, we present high resolution
trace element and stable isotope proxy records from well
-
preserved aragonitic Late Miocene and
Pliocene
Tridacna
spp.
shells, sampled along the coast of East Kalimantan (Indonesia) and Sabah
(Malaysia), respectively. Our multi
-
proxy approach utilizes LA
-
ICPMS El/Ca ratios (e.g. Mg/Ca,
Sr/Ca, Ba/Ca) and micromilled stable isotope profiles (

18
O,

13
C).
Records obtained fr
om our
Miocene specimens show a remarkable agreement in Mg/Ca, Sr/Ca and

18
O and can be aligned
with the shell banding pattern.

18
O intra
-
annual variability indicates a palaeoseasonality of 3
-
4\°C
(if interpreted as being temperature
-
controlled only). Ba/
Ca profiles from Pliocene tridacnin shells
are characterized by pronounced, episodically occurring peaks with a high intrashell
reproducibility. Very similar Ba/Ca signals found in modern
Tridacnagigas
have been interpreted
as palaeoproductivity indicators
(Elliot et al., 2009). Records of a modern
Tridacna
spp. from
Sabah are utilized for comparison and calibration purposes
.

}, url = {http://www.icp2013.cat/USB/PDF/P-183.PDF}, author = {Viola Warter and Wolfgang M{\"u}ller and Willem Renema} } @conference {2015, title = {Diversity and palaeoecology of Miocene coral-associated molluscs from East Kalimantan}, booktitle = {SAGE2013: Southeast Asian Gateway Evolution}, year = {2013}, address = {Museum fuer Naturkunde, Berlin}, abstract = {

Currently, SE Asia is the global marine centre of diversity. High diversity is concentrated in and around reefs. A large variety of organisms, including corals and fish, but also molluscs, crustaceans and echinoderms contribute to this high diversity. In order to understand the timing and the context of the origin of the modern biodiversity hotspot, the fossil record needs to be documented. However, reef facies often suffer strong diagenesis, compromising the fossil record of reef and reef-associated organisms. Here we present an assessment of a well-preserved Late Miocene mollusc fauna from Bontang (East Kalimantan, Indonesia). The fauna is found in association with branching corals, dominated by Dictyaraea. The mollusc fauna is dominated by predatory and browsing carnivorous snails and includes reefal indicators such as the gastropod Coralliophyla and the bivalve Tridacna. The new Bontang fauna gives a glimpse of the diversity and ecological composition of a Late Miocene mollusc fauna from a so-called coral-carpet environment.

}, author = {Aires Kusworo and Sonja Reich and Frank P. Wesselingh and Nadiezhda Santodomingo and Willem Renema} } @conference {2014, title = {Mollusks as seagrass indicators in the Miocene of Indonesia}, booktitle = {SAGE 2013: Southeast Asian Gateway Evolution}, year = {2013}, address = {Museum fuer Naturkunde, Berlin}, abstract = {

Today\’s centre of maximum marine biodiversity is located in the Indo-Malayan region. Understanding the development of this biodiversity hotspot through the Cenozoic could answer numerous questions about the responses of highly diverse faunal associations to small and large scale environmental changes. When assessing marine biodiversity through time comparisons of taxon diversity are only meaningful when comparing faunas from similar habitats. To evaluate diversity through time within the same ecological setting, it is indispensable to reliably discriminate different habitats. A good example for the difficulties which may occur when identifying marine paleo-habitats is the challenge of recognizing seagrass vegetation in the fossil record. Due to the low preservation potential of marine angiosperms, indirect indicators, e.g. associated organisms with a higher potential for preservation, are commonly used to infer the presence of seagrass meadows in the geological past. Because of their high fossilization potential and their abundance in marine habitats mollusks yield the possibility to be useful paleo seagrass indicators. Here we assess the potential use of indicator species, species and feeding guild composition of whole assemblages, as well as stable isotope signals in shells for their suitability to determine seagrass vegetation in the Miocene of Indonesia.

}, author = {Sonja Reich and Frank P. Wesselingh and Willem Renema and Warter, Viola} } @conference {2013, title = {Mollusk faunas as indirect indicators for palaeo-seagrass vegetation}, booktitle = {Geological Society of America Abstracts with Programs}, year = {2012}, abstract = {

Seagrass ecosystems play an important role in sedimentation processes and nutrient cycling and support local biodiversity by providing food and shelter for numerous associated organisms. These ecosystems have been around since the Late Cretaceous. In order to understand their emergence in geological time and their response to past perturbations we have to be able to recognize seagrass communities in the fossil record. However, seagrass itself hardly fossilizes and therefore we are searching for indirect indicators to recognize ancient seagrass vegetation. In this contribution we review molluscan evidence for palaeo-seagrass settings. Indicator species are rare since the majority of seagrass associated molluscs occurs in other marine habitats as well. Furthermore, those habitats appear to be patchy, both spatial and temporal, resulting in mixed occurrences of seagrass and non-seagrass faunas. Often only the high abundance of certain mollusc groups and the general taxonomic composition of a fauna points to seagrass environments. However, the distribution of gastropod trophic guilds in species richness versus abundance data appears to yield patterns that may be very characteristic for the identification of fossil seagrass associated faunas. We are currently applying Indirect PaleoSeagrass Indicators (IPSI\’s) to a number of fossil and modern shelly samples, both from seagrass and non-seagrass environments. We also briefly review potential sedimentary and geochemical IPSI\’s as well as fossil groups different than molluscs. Identifying seagrass environments enables us to assess diversity trends in such ecosystems through time and to study their response over time intervals with major environmental and climate change.

}, author = {Sonja Reich and Frank P. Wesselingh and Willem Renema} } @conference {2006, title = {Foraminiferal assemblages in Miocene carbonates of Indonesia}, booktitle = {Southeast Asian Gateway Evolution: SAGE2013}, year = {2013}, month = {11/03/2013}, address = {Museum fuer Naturkunde, Berlin}, abstract = {Neogene carbonates in Indonesia are characterised by different depositional environments. We studied localities outcropping on Mangkalihat Peninsula, Kutai Basin, and Java, that were deposited in a time interval from Early (Te5) to Middle Miocene (Tf2). In order to reconstruct depositional environments and obtain biostratigraphic information, larger benthic foraminifera (LBF) assemblages were analysed from these three locations. The northernmost, and stratigraphically oldest, from the studied carbonates are exposed on Mangkalihat Peninsula. They were formed in shallow-water environment on carbonate platform. Stratigraphically important LBF indicate Early to Middle Miocene age (Te5-Tf1). Towards the south, in the Kutai Basin, isolated patch reefs occur within siliciclastic sediments, developed in mixed carbonate-siliciclastic depositional systems. In general, LBF assemblage is indicative of low-light conditions typical for mesophotic reefs. Based on LBF late Early to Middle Miocene age (Tf1-Tf2) can be suggested. The southernmost carbonate exposures are located on Central Java, in the Bulu Limestone member. The LBF assemblage composition indicate environmental conditions typical for continental shelf edge. Middle Miocene (Tf2) can be inferred for these limestones based on LBF. Here we present an overview of Indonesian Early to Middle Miocene LBF assemblages in a range of depositional environments. We will assess the interplay between stratigraphical and environmental control on LBF assemblages. }, author = {Vibor Novak and Willem Renema} } @conference {2004, title = {Larger benthic foraminifera {\textendash} faunal pioneers in mixed carbonate-siliciclastic systems}, booktitle = {2012 GSA Annual Meeting}, year = {2012}, month = {04/11/2012}, address = {Charlotte, NC}, abstract = {Larger benthic foraminifera are one of the most abundant and widespread organisms in shallow marine tropical environments. Their role as rapid colonizers of new substrates has been suggested, but little is still known to support this idea. To address this question, larger benthic foraminifera assemblages have been studied in the paleoenvironmental reconstruction of a Langhian (Middle Miocene) shallow-water patch reef, as part of a broader multitaxon fossil comunity analysis, including corals, coralline algae, and bryozoans. The studied outcrop (approx. 80 m wide and 25 m thick) is located at the northeast margin of the Kutai Basin near Bontang (Indonesia). The patch-reef was developed in mixed carbonate-siliciclastic depositional environment and despite the high terrigenous input affecting water transparency, this reef contains a diverse marine biota. Five different facies types were distinguished based on lithology and fossil content: foraminifera packstone, bioclastic packstone with foralgal communities, thin-platy coral sheetstone, platy-tabular coral platestone, and shales. Excluding the fossil barren shales facies, only larger benthic foraminifera occur in all four remaining facies types, showing the ability to rapidly adapt to changes in environment. In the current study, high siliciclastic input caused fluctuations in light levels, but also resulted in deposition of soft-bottom substrate. In newly developed conditions, the larger benthic foraminifera appear first and mark the initiation of reef growth. The persistence of LBF throughout the fossil reef succession indicates their high tolerance to terrigenous input and also highlight the role of foraminifera as primary colonizers, proving themselves as important faunal pioneers, particularly in mixed carbonate-siliciclastic systems.}, author = {Vibor Novak and Nadiezhda Santodomingo and Willem Renema} } @conference {2003, title = {Burdigalian turbid water patch reef environment revealed by larger benthic foraminifera}, booktitle = {The EGU General Assembly 2012}, year = {2012}, month = {22/04/2012}, address = {Vienna}, abstract = {Ancient isolated patch reefs outcropping from siliciclastic sediments are a trademark for the Miocene carbonate deposits occurring in East Kalimantan, Indonesia. They develop in transitional shelf sediments deposited between deltaic and deep marine deposits (Allen and Chambers, 1998). The Batu Putih Limestone (Wilson, 2005) and similar outcrops in adjacent areas have been characterized as shallow water carbonates influenced by high siliciclastic input, showing low relief patch reefs in turbid waters. Larger benthic foraminifera (LBF) are excellent markers for biochronology and paleoenvironmental reconstruction. This study aims to reveal age and paleoenvironment of a shallow water carbonate patch reef developed in mixed depositional system by using LBF and microfacies analysis. The studied section is located near Bontang, East Kalimantan, and is approximately 80 m long and 12 m high. It is placed within Miocene sediments in the central part of the Kutai Basin. Patch reef and capping sediments were logged through eight transects along section and divided into nine different lithological units from which samples were collected. Thin sections and isolated specimens of larger benthic foraminifera were analyzed and recognized to species level (where possible) providing age and environmental information. Microfacies analysis of thin sections included carbonate classification (textural scheme of Dunham, 1962) and assemblage composition of LBF, algae and corals relative abundance. Three environmentally indicative groups of LBF were separated based on test morphology, habitat or living relatives (Hallock and Glenn, 1986). Analysed foraminifera assemblage suggests Burdigalian age (Tf1). With use of microfacies analysis nine successive lithological units were grouped into five facies types. Paleoenvironmental reconstruction of LBF fossil assemblage indicate two cycles of possible deepening recorded in the section. Based on high muddy matrix ratio in analyzed thin-sections we still cannot conclude whether they were deeper water assemblage, or that they occurred in shallower water and influenced by turbid conditions as the result of terrigenous input. According to preliminary analysis and siliciclastic content in the sediments the later one should be more likely. Further work will include additional fossil groups analysis (corals, algae and bryozoans), detailed petrographical analysis and Strontium isotope stratigraphy.}, author = {Vibor Novak and Willem Renema and the Throughflow Project} } @conference {1993, title = {Towards a synthesis of Cenozoic pantropical paleontology}, booktitle = {12 ICRS}, year = {2012}, month = {8-13 July 2012}, address = {Cairns, Australia}, url = {http://www.icrs2012.com/Downloads/ICRS2012_Book_of_Abstracts.pdf}, author = {Kenneth G. Johnson and James Klaus and Willem Renema and Jonathan A. Todd} } @conference {1992, title = {Origins of coral diversity in Southeast Asia}, booktitle = {5th International Symposium on Deep-Sea Corals 2012}, year = {2012}, month = {1-6 April 2012}, address = {Amsterdam, The Netherlands}, author = {Nadiezhda Santodomingo and Kenneth G. Johnson and Willem Renema and the Throughflow Project} } @conference {1981, title = {Palaeoenvironmental reconstruction of a Miocene patch reef in East Kalimantan (Indonesia): a close-up on the bryozoan component}, booktitle = {IBA Larwood Meeting }, year = {2012}, month = {31/05/2012}, address = {Brno Czech Republic}, author = {Emanuela Di Martino and Paul D. Taylor and Vibor Novak and Nadiezhda Santodomingo and Anja R{\"o}sler and Juan Carlos Braga and Kenneth G. Johnson and Willem Renema} } @conference {1978, title = {Environmental reconstruction of a Langhian patch reef (East Kalimantan, Indonesia)}, booktitle = {Lyell Meeting 2012}, year = {2012}, month = {29/03/2012}, author = {Vibor Novak and Nadiezhda Santodomingo and Anja R{\"o}sler and Emanuela Di Martino and Juan C. Braga and Paul D Taylor and Kenneth G. Johnson and Willem Renema} } @conference {1977, title = {Bryozoans from a Langhian patch reef in East Kalimantan (Indonesia)}, booktitle = {Giornate di Paleontologia XII edizione {\textendash} Catania, 24-26 Maggio 2012 }, year = {2012}, month = {24/05/2012}, address = {Catania, Italy}, author = {Emanuela Di Martino and Paul D. Taylor and Vibor Novak and Nadiezhda Santodomingo and Anja R{\"o}sler and Juan Carlos Braga and Kenneth G. Johnson and Willem Renema} } @conference {1963, title = {Late Cenozoic history of the Southeast Asian marine biodiversity maximum: new data for old questions}, booktitle = {Palaeontological Association Annual Meeting}, year = {2011}, month = {19/12/2011}, address = {Plymouth}, author = {Kenneth G. Johnson and Willem Renema} } @conference {1960, title = {Molluscs from underwater meadows - on the Miocene diversification of Indo-Pacific molluscan faunas associated to seagrass}, booktitle = {18th Phd-Day Biodiversiteit}, year = {2011}, month = {09.12.2011}, address = {NCB Naturalis, Leiden, the Netherlands}, author = {Sonja Reich and Frank P. Wesselingh and Willem Renema} } @conference {1954, title = {Reconstructing the origin of the Indo-Malayan marine biodiversity hotspot - First glimpses from the fossil record}, booktitle = {Annual Meeting of the Paleontological Society, Vienna, Austria}, year = {2011}, month = {12/09/2011}, publisher = {Contributions to Paleontology}, organization = {Contributions to Paleontology}, address = {Vienna}, author = {Sonja Reich and Frank P. Wesselingh and Willem Renema} } @conference {1947, title = {Southeast Asian and Caribbean Cenozoic Reef-coral diversity and the importance of large new collections}, booktitle = {11th Symposium on Fossil Cnidaria and Sponges}, year = {2011}, month = {26-30/August/201}, publisher = {M. aretz, S. Delculee, J. Denayer, And E. Poty (Eds.)}, organization = {M. aretz, S. Delculee, J. Denayer, And E. Poty (Eds.)}, author = {Kenneth G. Johnson and Brian R. Rosen and Nadiezhda Santodomingo and Willem Renema} }