Structure and Evolution of the Canada Basin: An Aerogeophysical Study

9321628布罗泽纳和科瓦奇该奖项支持对加拿大北部盆地(北冰洋盆地的一部分)进行地球物理调查。对加拿大盆地构造演化的充分了解对于确定阿拉斯加、加拿大和西伯利亚北缘的地质演化以及确定发生古气候变化的构造格架至关重要。该区域目前的区域地球物理知识还不够完整，不足以充分约束该区域演化的零级构造模型。这反映在围绕这些模型的时机和最基本的构造特征的持续的科学争论中。该项目将对加拿大盆地北部进行区域航空重力-航磁调查，目的是确定该地区的结构和构造演化。为了进行这些飞行，海军研究实验室(NRL)将在铂部署其配备了NRL机载地球物理传感器套件(AGSS)的RP-3猎户座远程飞机。巴罗，阿拉斯加，对加拿大盆地的一段进行了一到两个月的研究，选择提供重要构造特征诊断的可能性最高的开放方向和时间。来自国家科学基金会的资金将部分支持一个月的实地项目。NRL将通过内部研究资金和其他联邦机构的支持来支持成本的平衡。AGSS除了标准的机载质子进动磁强计外，还包括多个冗余重力仪、动态GPS和雷达/激光高度计系统。该系统已于1991年和1992年在格陵兰岛成功地收集了超过20万线公里的高质量重、磁和地形数据。此外，作为拟议工作的试点方案，1992年在毗邻加拿大北极的加拿大北部盆地收集了4万线公里的类似数据。通常，在所建议的高度和速度(600米和240节)下，该系统在轨道交叉口的精度约为2-3 mgAl(均方根)，分辨波长为15公里或更长的地壳特征。该项目将在合作的国际计划框架下进行，来自美国、加拿大和俄罗斯的科学家将参与其中。这项工作将产生一个地球物理数据集，用于解释该区域的构造和地质演化，但该数据集也将被更广泛的地球科学界的许多部分使用。

9321628 Brozena and Kovacs This award supports a geophysical investigation of the northern Canada Basin, part of the Arctic Ocean basin. A well constrained understanding of the tectonic evolution of the Canada Basin is critical for determining the geological evolution of the northern margins of Alaska, Canada, and Siberia, and for determining the tectonic framework under which paleoclimatic change occurred. The current regional geophysical knowledge of the region is not complete enough to adequately constrain even zeroth-order tectonic models of the evolution of the region. This is reflected in the continuing scientific controversy over the timing and most basic tectonic characteristics of those models. This project will conduct a regional aerogravity- aeromagnetic investigation of the northern Canada Basin with the goal of determining the structure and tectonic evolution of this region. To conduct these flights, Naval Research Laboratory (NRL) will deploy its RP-3 Orion long-range aircraft equipped with the NRL Airborne Geophysical Sensor Suite (AGSS) from Pt. Barrow, Alaska for a one to two month study over a section of the Canada Basin chosen to provide the highest likelihood of important tectonic signatures diagnostic of opening direction and timing. Funds from NSF will partially support one month of the field program. NRL will support the balance of the costs with internal research funds and support from other Federal agencies. The AGSS consists of multiple redundant gravimeter, kinematic GPS, and radar/laser altimeter systems in addition to a standard airborne proton precession magnetometer. This system has successfully collected over 200,000 line-km of high quality gravity, magnetics, and topography data over Greenland in 1991 and 1992. In addition, 40,000 line-km of similar data were collected over the northern Canada Basin adjacent to Arctic Canada in 1992 as a pilot program for the proposed work. Typically, the accuracy of the system at the altitudes and speeds proposed (600m and 240 knots) is about 2- 3 mGal (root-mean-square) at the track crossings, resolving crustal features with wavelengths of 15 km and longer. The project will be performed under the framework of a cooperative, international program involving scientists from the United States, Canada, and Russia. This work will yield an geophysical data set that will be used to interpret the tectonic and geologic evolution of the region but the data set will also be used by many parts of the broader earth sciences community.