Abstracts with Programs - Geological Society of America

SESSION NO. 31
the case of minerals containing the calcium ion, like gypsum or calcite, their dissolution rate is
also crucial in the investigation of the geological storage of CO 2 .
In standard dissolution experiments (batch, rotating disk, …), the mineral is dissolving in
stirred water. So the dissolution kinetics is mixed with diffusive and convective contributions.
For hard minerals, dissolution is so slow that it drives the whole kinetics. But for softer minerals,
dissolution, diffusion and convection timescales are of the same order of magnitude and their
respective contributions can be difficult to disciminate.
As an example, we have collected dissolution rates of gypsum in water measured by
various methods found in the literature. The deduced dissolution rate constants span over
several decades. Therefore we have analysed the hydrodynamics of the experimental setups,
eliminated the diffusive and convective contributions and deduced from them the pure surface
reaction rate constant of gypsum in water. It appears to be much smaller than expected
from the literature results. An holographic interferometry experiment, performed in still water,
is carried out and enables to measure directly this rate constant. Both values agree within
experimental uncertainty, which confirms the unexpected small value of the dissolution rate
constant of gypsum, and give clues to understand the discrepancy between the reported
values of calcite dissolution rate.
31-2 BTH 8 Maldini, Faldo
OBLIGATORY TECHNOLOGY TRANSFER TO MAXIMIZE THE USING OF ENERGY
RESOURCES IN DEVELOPMENT COUNTRY. STUDY CASE: GEOTHERMAL IN INDONESIA
MALDINI, Faldo, University of Indonesia, Depok 12620 Indonesia,
faldo.maldini@gmail.com
Today the world faces a serious problem about energy. Energy that usually created from
fossil like oil is decreased day by day. It also gives impact to the environment because of the
emission. Many countries agree that they will make green energy system that will be used in
each country. It is also happened in Indonesia. From now, the world needs a renewable energy
that also clean and friendly for the environment.
Indonesia has abundant natural resources. One of renewable energy that Indonesia has
is geothermal energy. Indonesia has 40% resource if we compare it with the other country
resource around the world. It is equal to 27500 Mwe for electricity power. Geothermal also
become friendly to the environment because the emission is small.
Now, Indonesia’s Government has vision “25/25” for geothermal energy. It means that the
energy mix for Indonesia for the year 2025 is 25%. In fact, the geothermal still use for 3%
for today. Then, the use of geothermal energy system is still not independently builds from
Indonesia. Indonesia still joins the other company from abroad to produce geothermal energy.
There is potential problem that will be happened because the bad system of geothermal
management. We should learn from oil management. Indonesian has gotten from this natural
resources is very limited.
Now, the production of geothermal is on the move. We see that the companies from
abroad are still take part to produce geothermal energy system with Indonesia’s company,
PT Pertamina Geothermal Energy. We can classify the threats which are coming from the
existence condition in two categories: (1) the problems that rise from the imperfectness
policy; (2) The problems that rise from system technically used: engineering, processing,
and producing the geothermal energy today and for the future. . To prevent and deal with the
problems, there are three classifications of solutions that should be done: (1) The application of
transfer technology with four types that will be clearly inform in the fourth chapter of this paper;
(2) Improvement the education quality and capability to use technology that support Indonesia’s
student; (3) The support and believe from the government with this country capability.
31-3 BTH 9 Obst, Karsten
POTENTIAL ECONOMIC USE OF MIDDLE BUNTSANDSTEIN SALINE AQUIFERS IN
MECKLENBURG-WESTERN POMERANIA (NE GERMANY)
OBST, Karsten and BRANDES, Juliane, Geologischer Dienst, LUNG M-V,
Goldberger Str. 12, Güstrow, D-18273, Germany, karsten.obst@lung.mv-regierung.de
Clastic sediments of the Middle Buntsandstein are widely distributed in the eastern part of the
North German Basin. Several sandstone horizons are intercalated with silt- and claystones.
They form a multi-layered system of saline aquifers (Detfurth formation to Solling formation).
The potential of these aquifers for geothermal heat production and geological storage of natural
gas or carbon dioxide varies regionally.
The sandstones of the Middle Buntsandstein are fine- to medium-grained with clay content
higher than 10 % in average. They show good reservoir properties at the north-eastern margin
of the basin, e.g. porosities between 15-30 % and mean permeabilities of about 500 mD.
Towards the central basin areas in the SW, the porosities of the sandstones are reduced either
due to higher silt and clay content or by secondary cementation of the pore space. Changing
facies conditions and burial effects led to rather low permeabilities