ON THE IZUMI SANDSTONE GROUP

泉砂岩群是日本列岛早白垩世沉积物的产物，呈带状沉积岩，东西走向约500公里。本文试述了从纪伊半岛的泉山脉到九州的乌须市的五个新证据：1）岩木地植物群：该植物群显示落叶阔叶相，是日本上白垩世最重要的植物群之一。2）原化石：这个化石属被一些古生态学家认为是一个生命起源，但它显示了一个植物学证据。但作者认为这些化石的某些部分是不确定的。3）侵入的上新世太古宙岩石变质条件：在本群的西部。它是在角岩类岩石中发现的，中间夹有一些南极岩。4）在该组的西部地区：该组的数据在永前县马加哈马町的AOSHIMA已知。但其区域存在九州地区的走向。5）该群的构造：该群被南北走向的断层分隔为6个块体。在这些石块中发现了位于东部的倾斜的犬牙状结构。

IZUMI SANDSTONE GROUP HAS LONG KNOWN TO BE FORMED OF THEUPPER CRETACEOUS DEPOSITS IN THE JAPANESE ISLANDS; AND IT SHOWS A BELT-LIK SEDIMENTED ROCKS, AND TRENDS THE EAST-TO-WEST WITH THE LENGTH OF 500 KM. FROM THE IZUMI MOUNTAIN RANGEIN KII PENINSULA TO USUKI CITY IN KYUSHU.IN THIS REPORT, THE WRITER TRIES A DESCRIPTION ON FIVE NEW EVIDENCES,AS FOLLOWS;1) IWAKIJI FLORA: THIS FLORA SHOWS THE DECIDUOUS BROARD LEAVES FACIES, AND IS THE ONE OF THE MOST IMPORTANT FLORA OF THE UPPER CRETACEOUS IN JAPAN.2) ON THE ARCHASEZOSTERA: THIS FOSSIL-GENUS HAS BEEN CONSIDERED A LEBENSSPUPEN BY SOME PALAEOECOLOGISTS,BUT IT SHOWS A BOTANICAL EVIDENCE. HOWEVER, THE WRITER CONSIDERS THAT IT IS INCERTITUDE MATTER ON SOME PARTS OF THESE FOSSILS.3) METAMORPHOSED CONDITION BY THE INTRUSIVED PLOCENE ANDESITIC ROCKS: IN THE WESTERN PART OF THIS GROUP. IT HAS BEEN FOUND IN THE HORNFELS-LIKE ROCKS BY SOME INTRUDING OF ANDESITIC ROCKS.4) ON THE WESTERN AREA OF THIS GROUP: THE WESTERN-END OF THIS GROUP AHS BEEN KNOWN AT AOSHIMA, MAGAHAMA-CHO, EHIME PREFECTURE. BUT ITS AREA EXISTS OF TREDING IN KYUSHU OVER THE BUNGO-SUIDU(CHANNEL).5) STURUCTURE OF THIS GROUP: THIS GROUP IS SEPARATED SIX-BLOCKS BY THE FAULTS OF TRDNDING OF THE SOUTH -TO-NORTH. AND IN THESE BOLCKS WERE FOUND IN THE PITCHING CYNCLINAL STRUCTURE IN THE EASTWARD.