The diverse Grania fauna (Clitellata : Enchytraeidae) of the Esperance area, Western Australia, with descriptions of two new species

Seven species of the marine enchytraeid genus Grania Southern, 1913 are described from sediments sampled during the 2003 International Workshop on the Marine Flora and Fauna of Esperance Bay and the Recherche Archipelago, on the southern coast of Western Australia. Two species are new to science, the euryhaline Tasmanian G. dolichura Rota and Erseus, 2000 represents a new record for the state, and the remaining four species were known from other parts of Western Australia. Grania quaerens sp. n. is recognized by having a high chaetal index (= 5 short chaetal foot), small coelomocytes, penial apparati with long whip-like terminal stylets, conspicuous spermathecae with ectally bulbous ducts, and ectally granulated ampullae housing sperm rings in their ental region. Grania sperantia sp. n. is readily distinguishable by the complete lack of lateral chaetae, a multiple-banded pattern of the clitellum, extremely long sperm funnels, and the intrasegmental location of the spermathecal pores. The latter new species and four others in the collection (G. bykane Coates, 1990, G. crassiducta Coates, 1990, G. dolichura, and G. ersei Coates, 1990) are remarkable in possessing the head organ, a sensory structure unique to Grania that was not noted previously in Western Australian species. When considering the whole genus, the geographic pattern of the head organ appears southern-centred: of the 17 species of Grania reported to possess it, as many as 13 inhabit the southern latitudes. The seventh species of the Esperance collection, G. vacivasa Coates and Stacey, 1993, is notable for the kind of items found in its gut and the unusual appearance of its pygidium.

Salinity episodes and their reversal in the late pliocene of south-western Australia

IEECAS SKLLQG

Propagators and ridge jumps in a back-arc basin, the West Philippine Basin

We explore the tectono-magmatic processes in the western West Philippine Basin, Philippine Sea Plate, using bathymetric data acquired in 2003 and 2004. The northwestern part of the basin formed through a series of northwestward propagating rifts. We identify at least five sequences of propagating rifts, probably triggered by mantle flow away from the mantle thermal anomaly that is responsible for the origin of the Benham and Urdenata plateaus. Gravitational forces caused by along-axis topographic gradient and a similar to 30 degrees ridge reorientation appear to also be driving the rift propagations. The along-axis mantle flow appears to be reduced and deflected along the Luzon-Okinawa fracture zone, because the spreading system remained stable west of this major fault zone. North-east of the Benham plateau, a left-lateral fracture zone has turned into a NE-SW-trending spreading axis. As a result, a microplate developed at the triple junction.

山东山旺中新世孢粉植物及古气候和古生态研究

本文对山旺中新世孢粉植物群进行了详细的研究。在22，95米厚的山旺硅藻土剖面上系统地采集了130块孢粉样品，样品之间的采样距离为10-30厘米。鉴定出孢粉类型111种。以此为基础，对山旺碰藻土沉积期间的古气候和古生态进行了高分辨率定量的恢复和重建。 根据每种孢粉类型的生物地层信息，山旺中新世孢粉植物群形成的时代为中中新世。这个年龄值也与同位素测年的结果16.78-14.11 Ma，以及根据哺乳动物划分的生物地层带MN4-MN5相一致。 运用共存分析法定量重建了山旺中新世孢粉植物群形成时的各项气候参数的定量值。所包括的10个古气候参数值分别为： 年平均温度(MAT) 15.6-17.2ºC，最冷月平均温度(TCM)5.0-6.6 0 C，最热月平均温度(TWM) 24.6-27.8 ºC，温度的年较差( TD) 20. 0-25.5 0 C，年平均降雨量(MAP) 1162-1308mm，最热月份的平均降雨量( PwarmM)108-lllmm，最湿月份的平均降雨量(PwetM) 148-180mm，最干月份的平均降雨量(PDM) 16-59mm，最干及最 湿月份降雨量的差值(DP) 81-153mm，平均相对湿度(RH) 72-74%，共存分析的结果表明，在整个22.95米厚的研究剖面上，从底部到顶部的古植物群形成期间的古气候有一个轻微的波动，其中年平均温度的波动范围大约在3度左右，最热月平均温度的波动范围在l度左右， 最冷月平均温度的波动范围在4度左右， 年平均降雨量的波动范围在100毫米左右。 山旺中新世时的气候应属于Koppen's的“Cfa”气候类型，与现今武汉与芜湖地区的气候相似。 与现代山旺地区气候上的区别主要在于年平均降雨量、降雨量的分配，以及最冷月份的平均温度。 通过应用多元分析的方法，对山旺中新世时期的植被进行了重建。山旺中新世时期的古植被为“混交中生林”，在研究剖面从底部到顶部的时间轴上，“混交中生林”经历了“湿润环境下的混交中生林”，“干旱环境下的混交中生林”，“湿润湖岸环境下的混交中生林”，“山地、湿润及碱性环境下的混交中生林”，和“碱性环境下的混交中生林”等5个阶段的变化。山旺剖面所代表的山旺湖周围的地形在断裂构造运动的控制下，也经历了一系列的变化。