west. Our study offers a local framework, but its Pleistocene landscape record has regional significance. Most of all, it forms a much-needed basis for future, detailed studies on the build-up of the hominin site of Trinil, its fossil assemblages and numerical ages.

The Yogyakarta region is located in the southeastern part of Central Java, Indonesia. The region forms an elongated northeast – southwest-trending central depression bordered by two parallel faults in the west and east. These major faults divided the area into three parts, including the western, central and eastern parts. Herein, we investigate the relative uplift rate of the each part by using planktonic and benthonic foraminiferas. The foraminifera will show the initial position/datum of each part before uplift. Over sixty samples (primarily limestones and marls) were taken for this research. The uplift rates of each part were different and created a depressed block control by way of parallel faults. Based on foraminifera fossil observations, each block was in the same depositional environment (inner neritic) during N9. The present positions indicate that the western part was uplifted higher than the others, with this part being uplifted more than 590 meters. The central part was uplifted less than 120 meters, and the eastern part was uplifted above an altitude of 170-300 meters. Keywords: Foraminifera fossil, planktonic, benthonic, graben, uplift

Isolation of ureolytic bacteria and geochemical analysis of beachrock from Krakal-Sadranan Beach (Yogyakarta, Indonesia) were conducted to determine natural sedimentary characteristics of the beachrock. The beachrock was also examined to determine the depositional conditions and distribution of rare earth elements. An increased concentration of total rare earth elements, both heavy rare earth elements (terbium, dysprosium, yttrium, holmium, erbium, thulium, ytterbium, and lutetium) and light rare earth elements (lanthanum, cesium, praseodymium, neodymium, samarium, europium, and gadolinium) signals that the beachrock deposition process happened under oxidative environmental conditions. This study proposes the novel use of ureolytic bacteria in a depositional environment for carbonate control of a sedimentary process for the development of artificial rock to mitigate coastal erosion. The resulting bacterial strains are highly homologous to the 16S rDNA nucleotide sequence of the species Oceanobacillus profundus, Vibrio maritimus, and Pseudoalteromonas tetradonis.

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The limestone research within the Limboto Basin of Gorontalo Province becomes a new challenge, particularly for the study of planktonic foraminiferal biostratigraphy. This study uses the data obtained from the measured section in the north-western part of Limboto Lake. The purpose of this study is to determine the planktonic foraminiferal biozonation and the relative age of Limboto limestones. The analyzed planktonic foraminiferal fossils can be classified as well to moderately preserved of various species, in the context of abundance, categorized as frequent to abundant. There are three recognized planktonic foraminiferal biozones, i.e., two biozones for Miocene age (M13b and M14) and one biozone for Pliocene age (PL1). The Miocene biozones are named as Globorotalia plesiotumida partial range zone (M13b) and Pulleniatina primalis-Globoquadrina dehiscens concurrent range zone (M14), while the name of Pliocene biozone is Globorotalia acostaensis partial range zone (PL1). The results of this study can be a reference to propose an age of Limboto Limestone Formation. Identification and demarcation of the Limboto Limestone Formation are based on the time interval and relative age of the formation based on planktonic foraminifera.