The Neogene sedimentary fills of the Chichibu Basin in the northeastern part of the Kanto Mountains have been studied for many years in regard to its stratigraphy, paleontology and sedimentology. An attempt has been made here to present the basin configuration, its evolution and sedimentation pattern in the north to northwestern part of the Chichibu Basin. The Neogene sedimentary pile distributed in the survey area can be divided into the Ushikubi, Tomita, Nenokami, Miyado and Yoshida Formations in ascending order. The Ushikubi Formation has been subdivided into the Tonogaido Breccia, Ushikubitouge Conglomerate and Shirasu Sandstone Members. The Kannon-yama Fault divides the Ushikubi Formation into east and west sides, which can be compared each other by the arkosic sandstone bed containing fossil sea urchin, Kewia minuta. As a result, it become evident that the Ushikubitouge Conglomerate Member is much thicker in the Ushikubitouge area than the other area. Basal conglomerates, high-angle unconformity plain and consolidated faults along the basin margin indicate that the Chichibu Basin was formed by collapsing along the faults. The basin was deeper near Ushikubitouge, forming a NW-SE depression, about 1km wide, 2km long and approximately 200m deep. Judging from the facies of the Ushikubi Formation, the basin was filled with talus and debris flows first. As the tubular trace fossils occur in the upper part of the Ushikubi Formation, it is assumed that sea water have entered the Ushikubi Depression during the sedimentation of the upper Ushikubitouge Conglomerate Member. And, the basin changed to tidal and subtidal conditions after the time of the Shirasu Sandstone Member. The starting time of the Ushikubi Formation is during latest Early Miocene time also the Chichibu Basin formed little before this time.

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Present condition and utilization of groundwater yield concepts for the groundwater development projects have been studied to propose appropriate planning for the development of groundwater in the developing countries. The preference or circumstance of the groundwater utilization has significant socioeconomic value for the developing countries. Therefore, groundwater development projects have been extensively implemented for rapid growth of water demand. These groundwater development projects could be classified into 3 types: "Community Water Supply Project" by a single well, "Rural Water Supply Project" by multiple wells and "Regional Groundwater Development Project" by numerous wells. In such practical projects, for the purpose of studying the method for determination of groundwater yield, an fact finding inquiry was carried out by questionnaire survey. As a result, it is ascertained that the terms of "Optimal Yield" and "Appropriate Utilizable Yield" are exclusively utilized for any type of projects. These terms are based on the concepts of "Critical Pumpage Capacity for Individual Well" and "Quantitative Control for Well Field", respectively. Considerations of groundwater basin management and environmental impact are neglected in either case. Such actual circumstances and problems are examined by this study. Considering the rapid increase of groundwater demand, adaptation of the concepts of groundwater yield must be made based on the purpose, scope and scale of each project. If environmental impact is suspected, the concept of "Permissible Yield", however, must be applied for determination of groundwater yield. It is essential for the planning of groundwater development project to determine the groundwater yield in accordance with the project type, especially in the developing countries where the groundwater is extensively utilized.

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Miocene paleoenvironment around the Saijogawa area in Shobara city is reconstructed, based on vertical and horizontal changes of lithofacies and benthic fossil records in the previous studies of the Miocene Bihoku Group in this area. Geologic age of the section is also discussed on the basis of the calcareous nannofossil flora. Changes of lithofacies and fossil records show that the Bihoku Group was deposited with increasing water depth. Neritic fossil fauna was effected by the oceanic water, and "algae limestone" were recognized in the basal part of the Miocene. No brackish and/or intertidal deposits have been preserved in this area. Also Miocene paleoenvironment around the study area is reconstructed as an drowned valley surrounded by rocky or gravelly abrasion coast. Reconstructed paleoenvironment indicates that this transgression occurred under rapid and broad areal subsidence or sea level rising. The Bihoku Group of the study area can be correlated with the upper part of the Martini's biozone NN4, based on the occurrence of Sphenolithus heteromorphus, Helicosphaera ampliaperta and other species. The depositional period of the Bihoku Group in the study area seems to be less than 0.5 m.y. around 16 Ma, based on the present study and previous chronology.

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Changes of geochemical composition of mold by activity of earthworms have been examined by comparison of soils and fecal pellets of earthworms. They were collected from the Samta village, Bangladesh and three localities in San'in district, southwest Japan. The castings of the Samta earthworms are one of the largest pellets of the world, consisting of thick-walled tube shapes with more than 8cm length and about 3cm in diameter. The wall is composed of light brownish grey silty mud gradually become hardened when they are dried. In general fecal pellets of the Japanese earthworms are dark grey color, irregular round shaped with 2-5mm in diameter. They are relatively fragile, and softer than those of the Bangladesh. Major and trace elements were analyzed using XRF, and geochemical compositions of casting and pellets of earthworms were compared with those of the underlying soils at each site. The Samta earthworm casting shows depletion in Ca, As, Pb, Cu and Zn, but there are no significant anomalies in other elements compared to composition of soils. Earthworm pellets of the two examples in Japan show depletion in As, Pb and Cu relative to in situ soil composition, but Zn does not show significant variation from the soils in all examples. These earthworm pellets show enrichments in Ca in two examples suggesting an effect of preventing from acid soil formation. These compositional variations between earthworm products and soils suggest significant remediation of As and Pb for mold by earthworm activities.

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Dense aggregations of ophiuroids, assigned to the extant species, Ophiura sarsii sarsii Lutken, collected from three formations in Yamagata Prefecture, northern Honshu (Japan), are described. The materials originate from the Late Miocene Hongo Formation and from the Late Miocene-Early Pliocene Furukuchi and Noguchi Formations. Fossil specimens of this species have previously been recorded from the late Middle Miocene to Middle Pleistocene formations from Hokkaido in the north to Shizuoka Prefecture in the south. The present materials thus add new data for the temporal and spatial distributions of fossil Ophiura sarsii sarsii.

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