Sidescan sonar navigation from USGS cruise 1999-045-FA along the inner continental shelf of northern North Carolina (iss1999045_tracklines.shp)

The northeastern North Carolina coastal system, from False Cape, Virginia, to Cape Lookout, North Carolina, has been studied by a cooperative research program that mapped the Quaternary geologic framework of the estuaries, barrier islands, and inner continental shelf. This information provides a basis to understand the linkage between geologic framework, physical processes, and coastal evolution at time scales from storm events to millennia. The study area attracts significant tourism to its parks and beaches, contains a number of coastal communities, and supports a local fishing industry, all of which are impacted by coastal change. Knowledge derived from this research program can be used to mitigate hazards and facilitate effective management of this dynamic coastal system.
This regional mapping project produced spatial datasets of high-resolution geophysical (bathymetry, backscatter intensity, and seismic reflection) and sedimentary (core and grab-sample) data. The high-resolution geophysical data were collected during numerous surveys within the back-barrier estuarine system, along the barrier island complex, in the nearshore, and along the inner continental shelf. Sediment cores were taken on the mainland and along the barrier islands, and both cores and grab samples were taken on the inner shelf. Data collection was a collaborative effort between the U.S. Geological Survey (USGS) and several other institutions including East Carolina University (ECU), the North Carolina Geological Survey, and the Virginia Institute of Marine Science (VIMS).
The high-resolution geophysical data of the inner continental shelf were collected during six separate surveys conducted between 1999 and 2004 (four USGS surveys north of Cape Hatteras: 1999-045-FA, 2001-005-FA, 2002-012-FA, 2002-013-FA, and two USGS surveys south of Cape Hatteras: 2003-003-FA and 2004-003-FA) and cover more than 2600 square kilometers of the inner shelf. Single-beam bathymetry data were collected north of Cape Hatteras in 1999 using a Furuno fathometer. Swath bathymetry data were collected on all other inner shelf surveys using a SEA, Ltd. SwathPLUS 234-kHz bathymetric sonar. Chirp seismic data as well as sidescan-sonar data were collected with a Teledyne Benthos (Datasonics) SIS-1000 north of Cape Hatteras along with boomer seismic reflection data (cruises 1999-045-FA, 2001-005-FA, 2002-012-FA and 2002-013-FA). An Edgetech 512i was used to collect chirp seismic data south of Cape Hatteras (cruises 2003-003-FA and 2004-003-FA) along with a Klein 3000 sidescan-sonar system. Sediment samples were collected with a Van Veen grab sampler during four of the USGS surveys (1999-045-FA, 2001-005-FA, 2002-013-FA, and 2004-003-FA). Additional sediment core data along the inner shelf are provided from previously published studies.
A cooperative study, between the North Carolina Geological Survey and the Minerals Management Service (MMS cores), collected vibracores along the inner continental shelf offshore of Nags Head, Kill Devils Hills and Kitty Hawk, North Carolina in 1996. The U.S. Army Corps of Engineers collected vibracores along the inner shelf offshore of Dare County in August 1995 (NDC cores) and July-August 1995 (SNL cores). These cores are curated by the North Carolina Geological Survey and were used as part of the ground validation process in this study.
Nearshore geophysical and core data were collected by the Virginia Institute of Marine Science. The nearshore is defined here as the region between the 10-m isobath and the shoreline. High-resolution bathymetry, backscatter intensity, and chirp seismic data were collected between June 2002 and May 2004. Vibracore samples were collected in May and July 2005.
Shallow subsurface geophysical data were acquired along the Outer Banks barrier islands using a ground-penetrating radar (GPR) system. Data were collected by East Carolina University from 2002 to 2005. Rotasonic cores (OBX cores) from five drilling operations were collected from 2002 to 2006 by the North Carolina Geological Survey as part of the cooperative study with the USGS. These cores are distributed throughout the Outer Banks as well as the mainland.
The USGS collected seismic data for the Quaternary section within the Albemarle-Pamlico estuarine system between 2001 and 2004 during six surveys (2001-013-FA, 2002-015-FA, 2003-005-FA, 2003-042-FA, 2004-005-FA, and 2004-006-FA). These surveys used Geopulse Boomer and Knudsen Engineering Limited (KEL) 320BR Chirp systems, except cruise 2003-042-FA, which used an Edgetech 424 Chirp and a boomer system. The study area includes Albemarle Sound and selected tributary estuaries such as the South, Pungo, Alligator, and Pasquotank Rivers; Pamlico Sound and trunk estuaries including the Neuse and Pamlico Rivers; and back-barrier sounds including Currituck, Croatan, Roanoke, Core, and Bogue.

一项合作研究项目已针对美国弗吉尼亚州假角（False Cape）至北卡罗来纳州卢考特角（Cape Lookout）之间的北卡罗来纳州东北部海岸系统展开研究，完成了该区域河口、障壁岛与内陆架的第四纪地质框架测绘工作。该研究成果可为理解地质框架、物理过程与海岸演化之间的关联提供依据，时间跨度涵盖风暴事件至千年尺度。该研究区域的公园与海滩吸引大量游客，区域内分布多个沿海社区，并支撑当地渔业，而所有这些都受到海岸变化的影响。本研究项目所得认知可用于减缓灾害风险，并助力该动态海岸系统的高效管理。
本区域测绘项目生成了高分辨率地球物理（水深测量、背散射强度与地震反射）数据与沉积（岩心与抓斗采样）数据的空间数据集。高分辨率地球物理数据采集自障后河口系统、障壁岛群、近岸区域以及内陆架的多次勘测作业。沉积岩心采集自大陆及障壁岛沿线，内陆架则同时采集了岩心与抓斗采样样品。数据采集工作由美国地质调查局（U.S. Geological Survey, USGS）与东卡罗来纳大学（East Carolina University, ECU）、北卡罗来纳州地质调查局以及弗吉尼亚海洋科学研究所（Virginia Institute of Marine Science, VIMS）等多家机构合作完成。
内陆架的高分辨率地球物理数据采集自1999年至2004年间开展的6次独立勘测（其中哈特拉斯角以北的USGS勘测共4次：1999-045-FA、2001-005-FA、2002-012-FA、2002-013-FA；哈特拉斯角以南的USGS勘测共2次：2003-003-FA与2004-003-FA），覆盖面积超过2600平方千米的内陆架区域。1999年，研究人员在哈特拉斯角以北区域使用古野（Furuno）测深仪采集了单波束水深测量数据。其余所有内陆架勘测均使用SEA有限公司的SwathPLUS 234千赫兹测深声呐采集条带水深测量数据。研究人员使用泰莱达本图斯（Datasonics）SIS-1000设备在哈特拉斯角以北采集了啁啾地震数据与侧扫声呐数据，同时还采集了boom地震反射数据（对应航次1999-045-FA、2001-005-FA、2002-012-FA与2002-013-FA）。研究人员在哈特拉斯角以南区域使用Edgetech 512i设备采集啁啾地震数据，并搭配Klein 3000侧扫声呐系统（对应航次2003-003-FA与2004-003-FA）。研究人员在4次USGS勘测中使用Van Veen抓斗采样器采集了沉积样品，分别对应航次1999-045-FA、2001-005-FA、2002-013-FA与2004-003-FA。内陆架沿线的额外沉积岩心数据来自已发表的既往研究。
1996年，北卡罗来纳州地质调查局与矿产管理局（Minerals Management Service, MMS）开展合作研究，在北卡罗来纳州纳格斯黑德、基尔德福尔斯希尔斯与基蒂霍克近海的内陆架沿线采集了振动岩心（后称MMS岩心）。美国陆军工程兵团于1995年8月（对应NDC岩心）与1995年7-8月（对应SNL岩心）在戴尔县近海的内陆架沿线采集了振动岩心样品。这些岩心由北卡罗来纳州地质调查局保存，并作为本研究地面验证工作的一部分得到使用。
弗吉尼亚海洋科学研究所采集了近岸地球物理与岩心数据。本研究中近岸的定义为10米等深线与海岸线之间的区域。研究人员于2002年6月至2004年5月间采集了高分辨率水深测量、背散射强度与啁啾地震数据，并于2005年5月与7月采集了振动岩心样品。
研究人员使用探地雷达（ground-penetrating radar, GPR）系统在外岸障壁岛沿线采集了浅表层地下地球物理数据。东卡罗来纳大学于2002年至2005年间完成了该数据采集工作。作为与USGS合作研究的一部分，北卡罗来纳州地质调查局于2002年至2006年间通过5次钻探作业采集了旋转声波岩心（OBX岩心）。这些岩心分布于外岸群岛及大陆沿线区域。
USGS于2001年至2004年间开展了6次勘测，采集了阿尔伯马尔-帕姆利科河口系统内第四纪地层的地震数据，分别对应航次2001-013-FA、2002-015-FA、2003-005-FA、2003-042-FA、2004-005-FA与2004-006-FA。除航次2003-042-FA使用Edgetech 424啁啾系统与boom系统外，其余勘测均使用Geopulse Boom与克努森工程有限公司（Knudsen Engineering Limited, KEL）320BR啁啾系统。本研究区域包括阿尔伯马尔湾及其选定的支流河口，如南河、庞戈河、短吻鳄河与帕斯科坦克河；帕姆利科湾及其主干河口，如纽斯河与帕姆利科河；以及障后海湾，如库里蒂克湾、克罗阿唐湾、罗阿诺克湾、科尔湾与博格湾。