An Early Warning System for Identifying Drilling Problems: An Example From a Problematic Drill-Out Cement Operation in the North-Sea

2012 ◽  
Author(s):  
Eric Cayeux ◽  
Benoit Daireaux ◽  
Erik Wolden Dvergsnes ◽  
Gunnstein Saelevik ◽  
Mohamed Zidan
Keyword(s):  
North Sea ◽  
Early Warning ◽  
Early Warning System ◽  
Warning System ◽  
The North ◽  
The North Sea

Hazard assessment of landslide-prone areas on highly weathered dunite rock in Bello Oriente, Medellín, Colombia (Project Inform@Risk)

2020 ◽  
Author(s):  
Tamara Breuninger ◽  
Moritz Gamperl ◽  
Kurosch Thuro
Keyword(s):  
Early Warning ◽  
Early Warning System ◽  
Warning System ◽  
Informal Settlements ◽  
The North ◽  
The Andes ◽  
North Eastern ◽  
Landslide Early Warning ◽  
Steep Slopes ◽  
The City

<p>The project Inform@Risk, a collaboration of German and Colombian Universities and Institutes funded by the German government, aims to install a landslide early warning system in the informal settlements in Medellín, Colombia. In the recent past the city has suffered from multiple landslides, some of them with up to 500 casualties. The informal settlements in the steep slopes at the city borders grow rapidly, which destabilizes the ground and complicates the installation and operation of an early warning system. Therefore, key goal of the project is to include the community in the process of the development of the early warning system.</p><p>Medellín is embedded in the Aburrá Valley in the Cordillera Central of the Andes. The region around the city consists of different triassic and cretaceous metamorphic rocks and magmatic batholites and plutonites. Especially the north-eastern slope is prone to landslides, as it is very steep and made up of a deep cover of soil over highly weathered dunite rock.</p><p>During the first field trip, carried out in August 2019, former landslide areas were located, and ERT-measurements were conducted at the study site Bello Oriente in the northeast of Medellín. After a first evaluation of the findings, the soil cover seems to be over 50 m high in the middle of the slope, which indicates a deep-seated landslide, that might have been moving downhill very slowly for thousands of years. The more dangerous landslides however, which are much faster, are the shallow ones on the surface. These landslides can appear on top of each other and are distributed across the whole study area but are most concentrated between and above the last houses of the barrio. During a second field campaign in 2020, the ERT-profiles will be calibrated and complemented by drillings and the hazard map will be completed accordingly.</p>

Long-term monitoring of coastal saltwater intrusion using the geoelectrical monitoring system SAMOS

2021 ◽  
Author(s):  
Michael Grinat ◽  
Mathias Ronczka ◽  
Thomas Günther ◽  
Dieter Epping ◽  
Vitali Kipke ◽  
...  
Keyword(s):  
Groundwater Recharge ◽  
Monitoring System ◽  
North Sea ◽  
Early Warning ◽  
Groundwater System ◽  
Transition Zones ◽  
The North ◽  
The North Sea ◽  
Local Water

<p>Efficient groundwater management is the key to a sustainable use of freshwater aquifers. In the coastal areas worldwide, saltwater intrusions caused by sea-level rise, overuse of freshwater resources and changing groundwater recharge is a major threat to the availability of freshwater. A reduced groundwater recharge combined with an increased extraction can lead to vertical upconing or lateral movement of the freshwater-saltwater transition zones, therefore reducing the local freshwater resources. Long-term and continuous observation of the freshwater-saltwater transition zones is crucial to implement early warning procedures, yields more detailed insight into the groundwater system and therefore enables early adjustment and adaptation of extraction rates if needed.</p><p>The SAltwater MOnitoring System (SAMOS) consists of two main parts: a vertical electrode chain of steel ring electrodes permanently installed in a backfilled borehole and a measuring system at the surface. The number of electrodes (commonly about 80) and distance between adjacent electrodes (commonly about 25 cm) is generally flexible. The chain of electrodes is connected to a lightweight and small resistivity meter (LGM, 4-Point light 10W). Thanks to the maximum output current of 100 mA and a voltage of 380 V a low power consumption is achieved and long-term and autonomous monitoring is enabled by solar panel based power supply. Furthermore, the system is designed to run predefined measurement protocols and transfers the data to a remote server immediately after a measurement is performed. SAMOS is commonly installed in the transition zone between fresh- and saltwater allowing the detection of very slight resistivity changes (less than 1 Ohmmeter). While first systems were completely manufactured by LIAG, the latest subsurface systems were built by Solexperts which allowed us to include temperature sensors.</p><p>We present data from four SAMOS systems currently running at different locations. Two of them are installed in the central part of the freshwater lense of the North Sea island Borkum (in cooperation with Stadtwerke Borkum) in depths between 44 m and 65 m below the surface, close to freshwater wells of the local water supplier, thus monitoring the overall groundwater system and delivering data since 2009. Even though measurements immediately after the installation are disturbed by the drilling process and an adjustment to undisturbed natural conditions is observed, adapted inversion schemes allow to use all data. While in most cases only slight resistivity changes are observed up to now, at some depths larger seasonal resistivity changes occur at one Borkum site that can mostly be explained by changes of the groundwater recharge rate and changing pumping activities in a water catchment area. Two further systems have been installed in 2018 and 2020. One is located behind the dune line at the edge of the freshwater lense on the North Sea island Spiekeroog. In cooperation with the local water supply company OOWV (Oldenburg-Ostfriesischer Wasserverband) another system for their groundwater extraction fields is installed near Jever several kilometers from the coast-line used for early warning.</p>

scholarly journals The Risk of Tsunamis in Mexico

2020 ◽  
Author(s):  
Jaime Santos-Reyes
Keyword(s):  
High Risk ◽  
Early Warning ◽  
Early Warning System ◽  
Pacific Coast ◽  
Warning System ◽  
Low Risk ◽  
Tsunami Early Warning ◽  
The North ◽  
The Pacific ◽  
Preliminary Model

The paper reviews the risk of tsunamis in Mexico. It is highlighted that the Pacific coast of the country forms part of the so called “Ring of fire”. Overall, the risk of tsunami that has the potentiality to affect communities along the Pacific coast of the country are twofold: a). Local tsunami; i.e., those triggered by earthquakes originating from the “Cocos”, “Rivera” and the “North American” plates (high risk); and b) the remote tsunamis, those generated elsewhere (e.g, Alaska, Japan, Chile) (low risk). Further, a preliminary model for a “tsunami early warning” system for the case of Mexico is put forward.

An operational hydrographic warning system for the North Sea and the Danish Belts

1992 ◽  
Vol 12 (1) ◽  
pp. 65-81 ◽  
Author(s):  
Hans Jacob Vested ◽  
Henrik René Jensen ◽  
Helmer M. Petersen ◽  
Anne-Mette Jørgensen ◽  
Bennert Machenhauer
Keyword(s):  
North Sea ◽  
Warning System ◽  
The North ◽  
The North Sea

Evidencing a regime shift in the North Sea using early-warning signals as indicators of critical transitions

2015 ◽  
Vol 152 ◽  
pp. 65-72 ◽  
Author(s):  
N. Wouters ◽  
V. Dakos ◽  
M. Edwards ◽  
M.P. Serafim ◽  
P.J. Valayer ◽  
...  
Keyword(s):  
North Sea ◽  
Early Warning ◽  
Regime Shift ◽  
Warning Signals ◽  
Early Warning Signals ◽  
The North ◽  
Critical Transitions ◽  
The North Sea

scholarly journals North Atlantic and North Sea Climate Change: curl up, shut down, NAO and Ocean Colour

2005 ◽  
Vol 85 (6) ◽  
pp. 1301-1315 ◽  
Author(s):  
Robin Pingree
Keyword(s):  
Temperature Change ◽  
North Sea ◽  
North Atlantic ◽  
Early Warning ◽  
Sea Surface ◽  
Climate Forcing ◽  
Ocean Colour ◽  
The North ◽  
Nao Index ◽  
The North Sea

The strength of the North Atlantic Current (NAC) (based on sea-surface elevation slopes derived from altimeter data) is correlated with westerly winds (based on North Atlantic Oscillation [NAO] Index data over a nine year period [1992–2002] with 108 monthly values). The data time window includes the major change in climate forcing over the last 100 years (1995 to 1996). It is shown that the NAO Index can be used for early warning of system failure for the NAC. The correlation response or early warning time scale for western Europe and south England is six months. The decay scale for the NAC and Subtropical Gyre circulation is estimated as three years. Longer period altimeter elevation/circulation changes are discussed. The sea-surface temperature (SST) response of the North Sea to negative and positive NAO conditions is examined. The overall temperature response for the central North Sea to NAO index forcing, reflecting wind induced inflow, shelf circulation and local climate forcing, is ∼5 months. In years with strong North Atlantic winter wind induced inflow, under marked NAO positive conditions, mean temperatures (∼10.5°C) are about 1°C warmer than under negative conditions. In 1996 under extreme negative winter NAO conditions, the North Sea circulation stopped, conditions near the Dogger Bank became more continentally influenced and the winter (March) temperature fell to 3.1°C whereas in 1995 under NAO positive winter conditions the minimum temperature was 6.4°C (February). Seasonal advance of North Atlantic and North Sea temperature is derived in relation to temperature change. Temperature change and monthly NAO Index are discussed with respect to phytoplankton blooms, chlorophyll-a measurements, ocean colour data and the anomalous north-eastern Atlantic 2002 spring/summer bloom SeaWiFS chlorophyll concentrations.

scholarly journals The Risk of Tsunamis in Mexico

2020 ◽  
Author(s):  
Jaime Santos-Reyes ◽  
Tatiana Gouzeva
Keyword(s):  
High Risk ◽  
Early Warning ◽  
Early Warning System ◽  
Pacific Coast ◽  
Warning System ◽  
Low Risk ◽  
Tsunami Early Warning ◽  
The North ◽  
The Pacific ◽  
Preliminary Model

This paper reviews the risk of tsunamis in Mexico. It is highlighted that the Pacific coast of the country forms part of the so called “Ring of fire.” Overall, the risk of tsunami that has the potentiality to affect communities along the Pacific coast is twofold: (a) local tsunami; that is, those triggered by earthquakes originating from the “Cocos,” “Rivera,” and the “North American” plates (high risk) and (b) the remote tsunamis, those generated elsewhere (e.g., Alaska, Japan, Chile) (low risk). Further, a preliminary model for “tsunami early warning” system for the case of Mexico is put forward.

Sign in / Sign up

Export Citation Format

Share Document