Ocean Bottom Seismographic Survey of the Earthquake Swarm which occur beneath Mid Atlantic Ridge.

中大西洋海脊是板块(岩石圈)诞生的地方。由于通常的陆基地震仪距离太远，无法研究海脊，我们利用30-50灵敏的便携式OBSS(海底地震仪)进行了详细的微震观测和折射研究，以研究详细的地壳/上地幔结构。我们还研究了大西洋被动边缘，这是大西洋扩张的残余。我们在1994、1995和1996年带来了大约30个OBSS到大西洋。1994年，我们在大西洋进行了两次实验：一次是在雷克扬斯海脊，另一次是在比斯开湾。在前者中，我们成功地获得了微震的详细震中分布和山脊下的构造。在后者中，我们成功地开发了一种强大的可控源测量来研究地壳/上地幔结构，结合了单泡脉冲气枪和灵敏OBS。1995年，我们在…地区进行了一次广泛的OBS-气枪折射测量更多的是从冰岛北部的中大西洋海岭的一部分科尔宾西海岭到扬梅恩海岭，后者被认为是大西洋诞生之前的残余大陆。我们成功地获得了从Kolbeinsey Ridge到Jan Mayn Ridge的整个断面的连续详细结构，这对于研究大西洋的开放历史是非常重要的。1996年，我们还在大西洋进行了两次实验：一次是在挪威的沃林盆地，另一次是在雷克扬斯海脊向冰岛的过渡过程中。前者是为了说明挪威近海非常详细的地壳结构，在那里，大西洋开放的残余起点保持在流动玄武岩的下方。对于海上常用的地震反射方法来说，流动玄武岩是一种很难穿透的岩石，而我们的OBS折射测量可以穿透到地层下面。后者是为了研究从雷克雅内斯海脊到冰岛过渡过程中的微地震，这对于研究冰岛和海脊是如何形成的至关重要。我们还在这一地区进行了控制源研究，以阐明过渡时期的详细地壳结构。在这项研究中，我们使用了30台OBS和47台临时陆地地震仪。较少

Mid-Atlantic Ridge is the place where plate (lithosphere) is being born.. Because usual land-based seismographs are too far to study Ridges, we made use of 30-50 sensitive portable OBSs (Ocean Bottom Seismographs) to make detailed microearthquake observations and refraction studies to study detailed crustal/upper mantle structures. Also we studied Atlantic passive margins, which is a remnant of spreading of the Atlantic Ocean.We brought about 30 OBSs to the Atlantic in 1994,1995 and 1996. In 1994 we made two experiments in the Atlantic : one on the Reykjanes Ridge and the other in the Bay of Biscay. In the former, we succeeded to obtain a detailed hypocentral distribution of microearthquakes, and the structure beneath the Ridge. In the latter, we succeeded to develop a powerful controlled source survey to study crustal/upper mantle structure, with a combination of the single-bubble pulse airgun and the sensitive OBS.In 1995 we made an extensive OBS-airgun refraction survey in a region … More from Kolbeinsey Ridge, which is a part of Mid-Atlantic Ridge north of Iceland, to Jan Mayn Ridge, which is thought a remnant continent before the Atlantic was born. We have succeeded to obtain a continuous detailed structure for the whole transect from Kolbeinsey Ridge to Jan Mayn Ridge, which is quite important to study the history of opening of the Atlantic Ocean.In 1996 we also made two experiments in the Atlantic : one on the Voring Basin off Norway and the other in the transition from Reykjanes Ridge to Iceland. The former was to illustrate a very detailed crustal structure off Norway, where a remnant initiation of the opening of the Atlantic is kept beneath the flow basalt. The flow basalt is very impenetrable rock for the usual seismic reflection method used in the sea, however our OBS refraction survey can penetrate beneath the layr. The latter was to study micro-earthquakes beneath the transition from Reykjanes Ridge to Iceland which is essential to study how Iceland and the Ridge was formed. We also made controlled source study in this area to elucidate detailed crustal structure of the transition. We used 30 OBS plus 47 temporary land seismographs for this study. Less