Chirp shotpoint navigation from USGS cruise 2001-005-FA along the inner continental shelf of northern North Carolina (isc2001005_shots.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.

美国地质调查局（U.S. Geological Survey, USGS）牵头的合作研究项目，对北卡罗来纳州东北部海岸系统——从弗吉尼亚州假角（False Cape）至北卡罗来纳州卢考特角（Cape Lookout）——开展了研究，完成了河口、障壁岛及内陆陆架的第四纪地质框架填图。该研究成果为理解地质框架、物理过程与海岸演化在风暴事件至千年尺度下的关联机制提供了基础。研究区域内的公园与海滩吸引了大量游客，分布有多个沿海社区，并支撑着当地渔业，而所有这些都受到海岸变化的影响。本研究项目所得的知识可用于减缓灾害风险，并助力该动态海岸系统的有效管理。
本区域填图项目生成了多套空间数据集，涵盖高分辨率地球物理（水深测量（bathymetry）、后向散射强度（backscatter intensity）与地震反射（seismic reflection））与沉积学（岩芯（core）与抓取采样（grab-sample））数据。高分辨率地球物理数据采集于障壁河口系统内部、障壁岛群沿线、近岸区域及内陆陆架的多次勘测工作中。沉积岩芯采集于大陆及障壁岛沿岸，而岩芯与抓取采样均在内陆陆架完成。数据采集工作由美国地质调查局（USGS）与东卡罗来纳大学（East Carolina University, ECU）、北卡罗来纳地质调查局、弗吉尼亚海洋科学研究所（Virginia Institute of Marine Science, VIMS）等多家机构协作完成。
内陆陆架的高分辨率地球物理数据采集于1999年至2004年间开展的6次独立勘测：其中4次为哈特拉斯角以北的USGS勘测（编号1999-045-FA、2001-005-FA、2002-012-FA、2002-013-FA），另外2次为哈特拉斯角以南的USGS勘测（编号2003-003-FA与2004-003-FA），覆盖内陆陆架超过2600平方千米的区域。1999年，研究团队使用古野（Furuno）测深仪在哈特拉斯角以北采集了单波束水深测量数据。其余所有内陆陆架勘测均使用SEA有限公司的SwathPLUS 234kHz测深声呐采集条带水深数据。哈特拉斯角以北的勘测中，研究团队使用Teledyne Benthos（Datasonics）SIS-1000采集了啁啾地震（chirp seismic）数据与侧扫声呐数据，并辅以电火花地震反射数据（对应航次1999-045-FA、2001-005-FA、2002-012-FA与2002-013-FA）。哈特拉斯角以南的勘测（航次2003-003-FA与2004-003-FA）中，研究团队使用Edgetech 512i采集啁啾地震数据，并搭配Klein 3000侧扫声呐系统。在4次USGS勘测（1999-045-FA、2001-005-FA、2002-013-FA与2004-003-FA）中，研究团队使用范维恩采泥器（Van Veen grab sampler）采集了沉积样本。内陆陆架的额外沉积岩芯数据来自已发表的前期研究。
北卡罗来纳地质调查局与矿产管理局（Minerals Management Service, MMS）合作开展的一项研究，于1996年在北卡罗来纳州纳格斯黑德、基尔迪维尔希尔斯与基蒂霍克近海的内陆陆架采集了振动岩芯（vibracore，即MMS岩芯）。美国陆军工程兵团于1995年8月（NDC岩芯）与1995年7-8月（SNL岩芯）在戴尔县近海的内陆陆架采集了振动岩芯。这些岩芯由北卡罗来纳地质调查局保存，并作为本研究地面验证工作的一部分。
弗吉尼亚海洋科学研究所（VIMS）采集了近岸地球物理与岩芯数据。本研究中近岸定义为10米等深线（isobath）与海岸线之间的区域。2002年6月至2004年5月期间，研究团队采集了高分辨率水深测量、后向散射强度与啁啾地震数据。2005年5月与7月采集了振动岩芯样本。
东卡罗来纳大学（ECU）于2002年至2005年间，沿外岸障壁岛使用探地雷达（ground-penetrating radar, GPR）系统采集了浅表层地球物理数据。北卡罗来纳地质调查局于2002年至2006年间，通过5次钻探作业采集了旋转声波岩芯（OBX岩芯），作为与USGS合作研究的一部分。这些岩芯分布于外岸及大陆区域。
USGS于2001年至2004年间，通过6次勘测（2001-013-FA、2002-015-FA、2003-005-FA、2003-042-FA、2004-005-FA与2004-006-FA），完成了阿尔伯马尔-帕姆利科河口系统内第四纪剖面的地震数据采集。除航次2003-042-FA使用Edgetech 424 Chirp与电火花系统外，其余航次均使用Geopulse电火花与Knud Engineering Limited（KEL）320BR Chirp系统。本研究区域包括阿尔伯马尔湾及南河、庞戈河、阿勒加托河与帕斯科坦克河等典型支流河口；帕姆利科湾及纽斯河、帕姆利科河等干流河口；以及科里塔克湾、克罗阿坦湾、罗阿诺克湾、科尔湾与博格湾等障壁后海湾。